Astroblog

How do we deal with contrarians?

2012-02-16T22:01:00.003+10:30

I wanted to write about other things, but I was reading the story of Rachel North in Jon Ronson's "The Psychopath Test" when I read about the invasion of the Plasma Universe people over that Emily Lakwandallah's blog, and the paper from Michael Majerus's last experiment landed on my desk.

There were so many resonances I felt I had to write about this. If you are an amateur astronomer, at some stage you will come across people whose views are wildly divergent from what is accepted by science. Given that this is 2012, we are bound to come across them sooner rather than later. Do you ignore them or engage them?

There are dangers in engaging these people, it's a bit like entering a world of Fun House Mirrors where you can be trapped in endless, increasingly bizarre discussions. Fortunately, most of us will never have the experience of Rachel North, a survivor of the London Underground bombings.

Conspiracy groups insisted that she did not exist, but was a fabrication of an MI6 disinformation group. Leonid Elenin had a related experience, where various fringe groups (godlikeproductions, I'm looking at you) proclaimed he did not exist, and that his name was a code word for Extinction Level Event, but the rejection not of only your existence but of the traumatic experiences you survived is a fundamental blow to who you are as a person.

When you encounter these people, what can you do? You could ignore them. This is what most of us would do. Life is short, and arguing with people who have severely divergent views of reality, and very little willingness to give them up, is a long hard grind that can seem to sap your life away. Rachel North engaged them, she blogged on her experiences, and commented in the conspiracists threads. This bought more disbelief in her existence and death threats (why you would threaten someone who you thought didn't exist beggars belief). Eventually she turned up at a meeting of the conspiracy theorists, to show them she really existed.

Mike Majerus's story was a bit different, no one claimed he didn't exist. He wrote about the evolution of the Peppered Moth. Creationists seized on his work and claimed that it showed that the moths were not subject to natural selection, others muttered darkly the classic work had been faked. Mikes response was to create the most detailed outdoor experiment on natural selection in moths ever.

For six years he climbed trees, patiently observed moths in the early dawn as well as doing his normal work. His massive compliation of data unequivically shows the action of natural selection. Sadly, he died before he could publish he findings, but his colleagues banded together to ensure their publication.

Few of us have the courage of Rachel North, or the dedication of Mike Majerus, let alone the energy of the Bad Astronomer or the quiet patience of Leonid Elenin, what should we do when faced with contrarians? Is it worth our limited time and more meager reserves of courage and patience to face off with these people? After all, despite the best efforts of Rachel, Mike, BA and Leonid the contrarians have not given up their views.

The hard core contrarians will never give up their views, but around them are people who can be persuaded, and when contrarians show up we should keep them in mind. To me, that's why we should not be dismissive, but patiently explain why the current scientific view exists. I like to come at things a bit sideways, to try and get people to think about what the world would be like if the contrarian view was true. Be prepared to repeat yourself over and over again (it helps to have a preprepared list of links you can quickly cut and paste to good sources of information, like when someone claims there is no evidence of water in comets).

You may still think it's too much effort, and it can be hard work when all you want to do is take pictures of the sky, but I'd like to think that in solidarity with Rachel North we can stand up for rationality from time to time.

Book Review: The Changeling Detective

2012-02-15T22:49:00.004+10:30

First things first, before reading any further, put on the Angels song "Am I Ever Going to See Your Face Again" as loud as compatible with domestic harmony.

First things second,I liked this eBook novella, I really, really liked it. Now I have to qualify this statement.

Because I know the author, Phillip Berrie. Heck, he's one of my best friends (despite the fact I haven't actually spoken to him for a decade, that's my hyper disorganization). We've bush walked together, played chess and D&D together and he's had me help out on his real-time RPG's. Without out him, I would have never won an award for role playing a demented squirrel. And he supported my nascent attempts at writing fiction.

So you can see that I could be a wee bit biased when I praise his eBook. Now I need to convince you that the praise is worthy.

For as long as genres have been genres, their supposed boundaries have been transgressed. Almost as soon as we had hard bitten, roughly hansom detectives with monosylabic names, their trench-coated forms have been found trudging the streets of Mars or Magical Kingdoms (or Magical Kingdoms on Mars). It's giving nothing away to reveal that "The Changeling Detective" is located in the Sci-Fi**/Fantasy spectrum of "Trench-coat" Detective fiction*.

The Sci-Fi/Fantasy trench-coat detective crossover has given us an enormous number of variants on the central detective character. We've had ordinary humans in a magical world (Garrett; TunFair), magical Humans in an "ordinary" world (Harry Dresden; Chicago), marginally magical (and marginally competent) Humans in a magical world (Thraxas; Turai), we've had vampire detectives, robot dectectives, steampunk anti-magical detectives and bird-like alien detectives who live in inverted cones on Mars. Does the world need another Sci-Fi/Fantasy detective novel?

Heck yeah! The central character's ability (cue David O'Dohert's "very mild superpowers") is refreshingly original and cleverly thought out. Okay, so it's vaguely related to the powers of the bad guy in Larry Niven's "the Meddler", and the powers of the bad guys in "Faded Steel Heat", but the characters ability is sufficiently different, and drives the story in interesting directions, that these vague antecedents are irrelevant. You will note I haven't told you what the ability is (or the name of the central character). We'll, I'm not going to, even though the ability is revealed in the first chapter, the pleasant surprise of finding out what it is (and the clever ways it is used) is worth it.

Okay, having said that I have given readers of this review A Clue, see if you can work it out.

"The Changeling Detective" has appropriate nods to the trench-coat detective genre, but with refreshing twists and playful inversions of tropes. There is the obligatory attractive red-haired woman (Glenn Cook, I'm looking at you), but whose role is anything but eyecandy or the clichéd roles normally reserved for this archetypical character. Her story takes the plot in an parallel direction to the one triggered by the main character (cue the Angels again "She Keeps No Secrets From You"), and she plays important roles in the action.

The "Changelingverse" is a modern day world very similar to our own, there are no clouds of pixies or bands of grumpy dwarfs, and no pseudomedieval castles loom over the action. There are gormless bartenders, nosey neigbours and zombie savvy kids (no zombies actually feature in the novella though).

Oh, yes, there's action, the plot fairly kicks along at a cracking pace (but not in the Hollywood sense of "the plot's not making sense? Here's an explosion or two to distract you"). The plot also has as many twists and turns as the back road to Mt. Tambourine** so even as a somewhat jaded Krimi*** reader I was turning the pages to see what happened next.

You may notice I haven't given a synopsis of the plot. A large chunk of the plot evolves from the central characters ability, so I can't discuss the plot without revealing the ability. Suffice to say there's a Dame With A Case, bad guys with guns, gunshots, sirens in the night and enough of the Trenchcoat Detective tropes to keep Sam Spade happy. The ability is consistent in the Changelingverse (with plenty of "hey that's cool" and "how is the ability going to get them out of that" moments), no Deux ex Machinations occur and there is a sufficent smattering of the self-depreciating humour Australians are famous for.

The novella ends on a cliff-hanger, in the sense that although the immediate plot issue is resolved, there are clear loose ends that make you impatient for the next novel (in the same way the Jo Nesbo's detective solves the immediate crime, but the unresolved story of his partners murder leads into and ties together the next few novels).

My only real issue with "The Changling Detective" is that there isn't a good feeling of "sense of place". While the story is set in modern day Canberra, Australia's capital, it could be anywhere in the English speaking world. I've been to a number of the locations mentioned in the novella, and I didn't feel the book took me there.

True, Phil has two serious barriers to making a real sense of place. Firstly, it is Canberra, famously described as "a bloody good paddock ruined". It's the kind of place that makes Milton-Keynes and Bonn look exciting. Getting a sense of place from such a setting is difficult, even if you do mention Tuggeranong (but then, maybe the bland anonymity is its sense of place).

Secondly, the work is a novella, and you are up against space. It takes more than driving a Holden into a kangaroo while eating a meat pie to give a sense of place, just like it takes more than Jo Nesbo mentioning Fiords, rollmops and towns called Hallorgenvasenbaad gives you the sense of place in Norway, and more than walking out into a cloud of Pixies for Glenn Cook to give you the feeling of TunFair.

It takes space to subtley draw this out. It's easier for Jo Nesbo, his novels are 500+ page doorstops (even when you throw in Nazi's, Skinheads and gypsy crimelords there's plenty of space for exposition of "place"). In a novella you have to draw the plot more tightly, and Phil has used no cheap shortcuts. I am pleased to report no character cracks a tinny of Fosters in the whole novella. I think Phil has done a good job in the face of these limitations.

So if you want a fresh and engaging Sci-Fi/Fantasy trench-coat detective story whose character has a novel ability, and whose plot moves along at a cracking pace, I highly recommend "The Changling Detective". I give it 4.5 enchanted daggers out of 5 and I'm waiting for the next instalment.

* As opposed to police procedural, Sherlock Holmsian and "little old lady" versions of the detective genre

**Don't give me grief over Sci-Fi vs SF or whatever acronym you wish to use, I was there in the 70's. The arguments were pointless then and are still pointless.

*** see what I did there. Also, don't try this road in a camper van if you don't want a heart attack every 100 meters

**** one of the few lasting effects of my European postdoctoral stint is a tendency to call murder mystery novels Krimi's, helped along by our Swedish friends sendinging us Scandinavian Krimi's. Hence the Jo Nesbo references.

The Sky This Week - Thursday February 16 to Thursday February 23

2012-02-14T22:04:00.004+10:30

The New Moon is Wednesday February 22. Venus is easily visible in the western evening sky, drawing close to Jupiter. Jupiter dominates the evening sky in the north-west once Venus has set. Mars is in the eastern evening sky, not far from Saturn, which is near the star Spica. The Globe at Night light pollution survey is on from Feb 12-21.

Evening sky looking east as seen from Adelaide at 11:30 am local daylight saving time on Sunday February 12 showing Mars and Saturn, with the Moon very close to Spica. Similar views will be seen elsewhere at the equivalent local time. The inset shows the telescopic appearance of Saturn and it's Moons at this time. Click to embiggen.

The New Moon is Wednesday February 22.

Mars is in the constellation of Leo.

Mars is in the eastern sky late in the evening, rising around 9:15 pm (local daylight saving time), although it is still highest in the early morning. Mars continues to brightens rapidly.

Saturn is above the north- eastern horizon, not far from the bright star Spica. Saturn is high enough in sky in the early morning for telescopic observation, but is rising about 11:00 pm local daylight saving time.

Mercury is now lost in twilight.

Evening sky on Saturday February 18 looking west as seen from Adelaide at 8:30 pm local daylight saving time in South Australia showing Venus in Pisces, with Jupiter not far away. The insets shows the appearance of Venus and Jupiter and its Moons as seen telescopically at this time. Similar views will be seen elsewhere at the equivalent local time (click to embiggen)

Bright white Venus is readily visible in the evening western twilight sky from around half an hour after sunset for somewhat over an hour and a half.

Venus is in Aquarius this week. It comes close to Epsilon Piscium on the 23rd. Venus may drown the star out with its brightness.

Jupiter was at opposition, when it is biggest and brightest as seen from Earth, on Saturday the 29th of October.

However, Jupiter is still a great binocular object. Jupiter is visible for most of the night in the north-western sky, setting half an hour after midnight.

In the evening Jupiter is readily visible in the northern-western sky, from about twilight. It is coming closer to Venus, and the pair look very nice in the western evening sky.

Now is a still good time for telescopic observation of this massive world (although the window for observation is narrowing), or follow its moons in binoculars. For good telescopic observation Jupiter is best from 9 pm - 10 pm.

Although Jupiter is the most prominent now, there are lots of interesting things in the sky to view with a telescope. If you don't have a telescope, now is a good time to visit one of your local astronomical societies open nights or the local planetariums.

Globe at Night, the international light pollution survey, is running its second survey this year from February 12-21. Visit their websit e for easy to follow instructions and charts to estimate how dark your sky is.

Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pm AEDST. For further details and more information on what's up in the sky, see Southern Skywatch (this will be up dated to February a little later).

Cloud cover predictions can be found at SkippySky.

Globe at Night Light Pollution Survey for February 12-21

2012-02-14T21:53:00.002+10:30

Northern sky at 10 pm local daylight saving time in Australia showing Orion.

Globe at Night, the international light pollution survey, is running its second survey this year from February 12-21. There are two more to come March 13-22 and April 11-20. Visit their websit e for easy to follow instructions and charts to estimate how dark your sky is.

Basically, an hour or so after sunset (8-10 pm) head out, look to the north to find Leo, (if you are in the northern hemisphere) or south to find Crux (for us southern hemisphere types) or Orion (for everybody) then check how many stars are visible, and report your observations. It's a great excuse to get outdoors and look at the sky. You might even see the International Space Station or an Iridium flare.

This year you can submit your results a smart phone or tablet. To do this, you can use the web application at www.globeatnight.org/webapp/. Globe at Night is also on Facebook and Twitter.

In Which I am a Media Star (yet) Again

2012-02-14T21:05:00.003+10:30

I'm virtually saturating the media at the moment.

This Sunday (19 February) I will be on Ashley Walsh's program on 891 ABC Adelaide at 11:40 am ACDST (UTC +10:30) talking about the upcoming year in astronomy.

If you are not in Adelaide the LiveStream will be here.

On Monday evening I did an interview with ABC local radio Port Piri on a new drug which might hold promise for treating Alzheimer's disease. If it wasn't clear from the interview, so many drugs show promise in animal models, but fail utterly in humans. Wait for the human clinical trials before getting excited.

Monday evening also saw a Today Tonight program screen on the homoeopath Monika Milka, which features an interview with me and a demonstration of what homoeopathic dilutions look like (see image above). It's on the web at Today Tonight Adelaide (currently it's the first video "homoeopath", it will scroll down as the days go on). If you scroll down further, the current second last video (Chemical Cans) has an interview with me as well, in which I get the last word. These will eventually scroll into the archive section but look for homoeopath and Chemical Cans will find them.

I also have an article coming up in The Conversation, so keep your eyes peeled. My previous articles are here and here.

Reminder: Science Communicators SA: Speed Networking

2012-02-13T06:29:00.001+10:30

Just a reminder that Australian Science Communicators SA is kicking off 2012 with SPEED NETWORKING and the SA Inspiring Australia grants Science communication is about people. We are lucky to have loads of science communicators in South Australia, some with years of experience, others with fresh approaches using innovative ways to communicate with their audiences. If you are new to science communication, this is the perfect way to make contacts and find out more about what ASCSA has to offer. You’ll also have the chance to hear about the SA Inspiring Australia grants available in 2012.

WHEN: Tuesday, February 14, 2012 from 6:00 PM to 8:00 PM

WHERE: The Science Exchange,
55 Exchange Place
Adelaide, South Australia 5000
Australia

ENTRY Free, but please book through http://ascsaspeednetworking2012.eventbrite.com/

The Kepler-20 Exoplanetary System in Celestia

2012-02-12T21:20:00.003+10:30

Left image: The Kepler-20 solar system, simulated in Celestia. Right image: Simulation of the view from orbit around Kepler-20e, with Kepler-20b visible in the sky. Click on an image to embiggen.

The Kepler-20 system made a bit of a splash back in December, when it was announced that the system, previously known to have three Neptune sized worlds in it, had two Earth-sized worlds in it.

And this time Earth-Sized actually Means Earth-Sized, with the planets Kepler-20e being 0.87 times the radius of Earth and Kepler-20f being 1.03 times the radius of Earth. The previously smallest world was 1.42 times Earth’s radius, and most of the "Super Earths" are much larger.

This report was an important demonstration that earth-sized worlds can be picked up by Kepler. Kepler 20 is a G8 star very similar to the Sun, but its solar system is crammed into a space inside Mercury's orbit. Kepler-20e would have a surface temperature hotter than 1000 degrees C, and Kepler-20f would be more Venus like.

The interesting thing is that these are almost certainly rocky worlds. Many exoplanetary systems have gas giants very close to the parent star, and the current thinking is that the Gas giant form far out in the developing solar system, then migrate inwards. This should expel any rocky worlds closer to the star. The fact the Kepler-20e and f have survived suggests that we may still find terrestrial worlds in some of these systems (Kepler-20e could have been an ice-world that migrated in and had its ocean boiled off, leaving a rocky core, but Kepler-20f is too far out to be a boiled down ice-world).

You can read the NASA press release here, and thoughtful commentary by the Bad Astronomer and Emily Lakdawalla. The paper just came out in the print copy of nature, so I've used this as an excuse to make Celestia files for the system. One for the star (which isn't in the default files) and one for the planet.

As usual, copy the data here to plain text files (Kepler-20.stc and Kepler-20-planets.ssc), copy both of the files to the Celestia extras folder. The star is around 950 lightyears away in Lyra, so in the Celestia star browser, you will have to show around 500 stars to see Kepler-20 in the list.
I'll have to update my Celestia Exoplanet Tour as well.

===============Kepler-20.stc======================================
#Kepler survey

"Kepler-20"
{
RA 287.7000
Dec 49.3386
Distance 945.9 # light years from published data
SpectralType "G8"
AppMag 12.423
}
==============================================================================

==================Keper-20_Planets.ssc=================================
"b" "Kepler-20"

# Neptune like world
# All data from original papers

{
Texture "exo-class4.*"
NightTexture "exo-class4night.*"

Mass 8.7 # M.sin(i) = 8.7 Earth
Radius 12181.98 # 1.91 Earth radi, from paper

#InfoURL "http://en.wikipedia.org/wiki/Kepler-20b"

EllipticalOrbit {
Period 0.0101
SemiMajorAxis 0.04537
Eccentricity 0.32
ArgOfPericenter 267 #guess
Inclination 86.50
#MeanAnomaly 271
}

# likely to be in captured synchronous rotation
}

AltSurface "limit of knowledge" "Kepler-20/b"
{
Texture "extrasolar-lok.*"

}

"c" "Kepler-20"

# Neptune like world

{
Texture "exo-class4.*"
NightTexture "exo-class4night.*"

Mass 16.1 # M.sin(i) = 16.1 Earth
Radius 19580.46 # 3.07 Earth radi, from paper

#InfoURL "http://en.wikipedia.org/wiki/Kepler-20b"

EllipticalOrbit {
Period 0.0297
SemiMajorAxis 0.0930
Eccentricity 0.4
ArgOfPericenter 267 #guess
Inclination 88.39
#MeanAnomaly 271
}

# likely to be in captured synchronous rotation
}

AltSurface "limit of knowledge" "Kepler-20/c"
{
Texture "extrasolar-lok.*"
}

"d" "Kepler-20"

# Neptune like world

{
Texture "exo-class4.*"
NightTexture "exo-class4night.*"

Mass 20.17 # M.sin(i) = 20.1 Earth
Radius 17539.5 # 2.75 Earth radi, from paper

#InfoURL "http://en.wikipedia.org/wiki/Kepler-20d"

EllipticalOrbit {
Period 0.21249
SemiMajorAxis 0.3453
Eccentricity 0.6
ArgOfPericenter 267 #guess
Inclination 89.570
#MeanAnomaly 271
}

# likely to be in captured synchronous rotation
}

AltSurface "limit of knowledge" "Kepler-20/d"
{
Texture "extrasolar-lok.*"
}

"e" "Kepler-20"

# earth like world

{
Texture "venussurface.*"
# Using venus although it may be a magma world

Mass 1.67 # M.sin(i) = 1.67 Earth, upper limit of theoretical range
Radius 3844.5167 # 0.868 Earth radi, from paper

#InfoURL "http://en.wikipedia.org/wiki/Kepler-20e"

EllipticalOrbit {
Period 0.0167
SemiMajorAxis 0.05073
Eccentricity 0.28
ArgOfPericenter 267 #guess
Inclination 87.50
#MeanAnomaly 271
}

# likely to be in captured synchronous rotation
}

AltSurface "limit of knowledge" "Kepler-20/e"
{
Texture "venussurface.*"
OverlayTexture "ganymede-lok-mask.png"
}

"f" "Kepler-20"

# earth like world

{
Texture "ganymede.*"
# Using Ganymede as it may be giant ice world
# NightTexture "gasgiantnight.jpg"

Mass 3.04 # M.sin(i) = 3.04 Earth theoretical maximum
Radius 6569.34 # 1.03 Earth radi, from paper

#InfoURL "http://en.wikipedia.org/wiki/Kepler-20f"

EllipticalOrbit {
Period 0.0536
SemiMajorAxis 0.11038
Eccentricity 0.32
ArgOfPericenter 267 #guess
Inclination 88.68
#MeanAnomaly 271
}

# likely to be in captured synchronous rotation
}

AltSurface "limit of knowledge" "Kepler-20/f"
{
Texture "ganymede.*"
OverlayTexture "ganymede-lok-mask.png"
}

==============================================================================

Carnival of Space #236 is here.

2012-02-12T21:00:00.003+10:30

Carnival of Space #236 is now up at the AARTScope blog. There space drives for the future, amazing aurora, a recurrent nova in the Andromeda galaxy, why the Moons brightness is so variable, asteroids falling into black holes and much, much more. Pop on over and have a read.

Comet Al and the recovery of C/2003 T12

2012-02-12T18:47:00.003+10:30

A while back I reported on the recovery of comet C/2003 T13 SOHO (now renamed to P/2012 A3 SOHO). Now Comet Al has blogged about his experience here, accompanied by some great shots taken with iTelescope T11, a masterful piece of astrophotography where the comet is right on the limit of twilight.

Earth from Mars, February 2012

2012-02-12T18:17:00.002+10:30

Left image: Earth as seen from Mars looking north-west in the twilight of February 12, 2012, shortly after Sunset, as visualised in Stellarium. The location is approximately the same latitude on Mars as Adelaide is on Earth. The right image is what Earth would look like through a telescope. Click on any image to embiggen. An earlier version from November 2011 is here.

The evening sky on Mars is quite lovely at the moment, with Earth, Venus and bright Jupiter all lined up. Earth will disappear from view very soon as Mars moves into opposition (where the earth is directly between Mars and the Sun. From our point of view, Mars will be at it biggest and brightest and visible all night long).

Once again one of the top search terms for people visiting my blog, is "Earth from Mars", probably in response to more publicity about the "John Carter on Mars" movie. So, once more, here it is for you searchers.

Iridium Flare and Sirius

2012-02-09T21:33:00.004+10:30

Caught this iridium flare as it passed below Canis Major (click to embiggen). Unfortunately, I was a bit late, so I jogged the camera as i tried to get the shot. Still, not too bad. There's another falre below Canis major tomorrow night, so I'll have another go then.

Science Communicators SA: Speed Networking

2012-02-08T21:36:00.004+10:30

Australian Science Communicators SA is kicking off 2012 with SPEED NETWORKING and the SA Inspiring Australia grants

Science communication is about people. We are lucky to have loads of science communicators in South Australia, some with years of experience, others with fresh approaches using innovative ways to communicate with their audiences.

If you are new to science communication, this is the perfect way to make contacts and find out more about what ASCSA has to offer.

You’ll also have the chance to hear about the SA Inspiring Australia grants available in 2012.

WHEN: Tuesday, February 14, 2012 from 6:00 PM to 8:00 PM

WHERE: The Science Exchange,
55 Exchange Place
Adelaide, South Australia 5000
Australia

ENTRY Free, but please book through http://ascsaspeednetworking2012.eventbrite.com/

Drinks can be purchased from the bar.

The Sky This Week - Thursday February 9 to Thursday February 16

2012-02-07T21:47:00.005+10:30

The Last Quarter Moon is Wednesday February 15. Venus is easily visible in the western evening sky. Jupiter dominates the evening sky in the north-west once Venus has set. Mars is in the eastern evening sky, not far from Saturn, which is near the star Spica. On the 10th the waning Moon is near Mars, and on the 12th it is close to Saturn.

Evening sky looking east as seen from Adelaide at 11:30 am local daylight saving time on Sunday February 12 showing Mars and Saturn, with the Moon very close to Spica. Similar views will be seen elsewhere at the equivalent local time. The inset shows the telescopic appearance of Saturn and it's Moons at this time. Click to embiggen.

The Last Quarter Moon is Wednesday February 15.

Mars is in the constellation of Leo.

Mars is in the eastern sky late in the evening, rising around 9:30 pm (local daylight saving time), although it is still highest in the early morning. Mars brightens rapidly this week. The Moon is close to Mars on the 10th.

Saturn is above the north- eastern horizon, not far from the bright star Spica. Saturn is high enough in sky in the early morning for telescopic observation, but is rising about 11:00 pm local daylight saving time.

On the 12th, Saturn is close to the waning Moon, which is less than half a fingerwidth from the bright star Spica.

Mercury is now lost in morning twilight.

Evening sky on Saturday February 11 looking west as seen from Adelaide at 9:00 pm local daylight saving time in South Australia showing Venus in Aquarius, with Jupiter not far away. The insets shows the appearance of Venus and Jupiter and its Moons as seen telescopically at this time. Similar views will be seen elsewhere at the equivalent local time (click to embiggen)

Bright white Venus is readily visible in the evening western twilight sky from around half an hour after sunset for somewhat over an hour and a half.

Venus is in Aquarius this week. It is closest to Uranus on the 10th. You will need binoculars to see Uranus, Venus may drown the planet out with its brightness.

Jupiter was at opposition, when it is biggest and brightest as seen from Earth, on Saturday the 29th of October.

However, Jupiter is still a great binocular object. Jupiter is visible for most of the night in the north-western sky, setting half an hour after midnight.

In the evening Jupiter is readily visible in the northern-western sky, from about twilight. It is coming closer to Venus, and the pair look very nice in the western evening sky.

Now is a still good time for telescopic observation of this massive world (although the window for observation is narrowing), or follow its moons in binoculars. For good telescopic observation Jupiter is best from 9 pm - 10 pm.

Although Jupiter is the most prominent now, there are lots of interesting things in the sky to view with a telescope. If you don't have a telescope, now is a good time to visit one of your local astronomical societies open nights or the local planetariums.

Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pm AEDST. For further details and more information on what's up in the sky, see Southern Skywatch (this will be up dated to February a little later).

Cloud cover predictions can be found at SkippySky.

Carnival of Space #235 is here.

2012-02-05T23:41:00.002+10:30

Carnival of Space #235 is now up at The Constant Amateur. There's solar storms, parallax for amateurs, Pluto an a Stamp and much, much more. Pop on over and have a look.

I Said I was Going to Bed, But LASERS ON TELESCOPES!!

2012-02-03T22:29:00.001+10:30

via @Plutokiller http://mkwc.ifa.hawaii.edu/current/cams/camsanim.cgi?location=subaru-E&mode=multi

Comet C/2009 P1 Garradd near M92 - February 3, 2012

2012-02-03T22:03:00.004+10:30

Comet C/2009 P1 Garradd next to the globular cluster M92 (click to embigen).

These are just the preview images taken with iTelescope T4 and T 20 respectively. I've been remiss in blogging this fantastic comet/cluster pairing, but I've been organising graduate student lectures instead (missed out on two days of imaging because I was distracted by lecture preparation and didn't press the button to launch my observing run :-(.

Exhausted now, heading to bed, I'll do proper analysis on the FITS images tomorrow, after a long sleep.

P/2003 T12 = 2012 A3 (SOHO).

2012-02-02T22:15:00.003+10:30

I wrote a little while ago of the fantastic cooperative effort from the STEREOHUNTERS that lead to the recovery of comet P/2003 T12. The Minor Planet Center has assigned the recovered comet the identifier 2012 A3 (SOHO).

It's predicted magnitude is around 12, Hidetaka Sato may have picked it up, and Comet Al, who first detected it in stereo images, has picked it up deep in the twilight with T11.

It will be a difficult object for some time as it climbs out of the twilight, but will be interesting to follow.

Carnival of Space #234 is here.

2012-02-01T07:57:00.002+10:30

Carnival of Space #234 is now up at Dear Astronomer, there's Dyson Sphere's around black holes, solar storms, global warming, another "blue Planet" photo and much more. Head on over and have a read.

Southern Skywatch February 2012 Edition Up

2012-02-01T06:48:00.002+10:30

Evening sky looking westh as seen from Adelaide at 20:30 pm local daylight saving time on Saturday February 25 showing Venus and Jupiter near the crescent Moon. Similar views will be seen elsewhere at the equivalent local time. Click to embiggen.

The February edition of Southern Skywatch is now up.

The Moon occults eta Geminorum on the 4th.

Venus is prominent in the early evening sky and is close to Jupiter the crescent Moon on the 25th.

Jupiter is prominent in the early evening sky, but is now a difficult telescopic object in the early evening.

Mars climbs higher in the evening sky and is close to the Moon on the 10th.

Saturn enters the evening sky sky and is close to the Moon on the 12th.

Mercury returns to the evening sky late in the month, but is not easy to see.

The Sky This Week - Thursday February 2 to Thursday February 9

2012-01-31T22:27:00.006+10:30

The Full Moon is Wednesday February 8. Venus is easily visible in the western evening sky . Jupiter dominates the evening sky in the north-west once Venus has set. Mars enters the evening sky, but is best visible in the morning sky heading towards Saturn, which is near the star Spica. The Moon occults the star eta Geminorum on the late evening of Saturday the 4th.

Morning sky looking east as seen from Adelaide at 2:00 am local daylight saving time on Sunday February 5 showing Mars and Saturn. Similar views will be seen elsewhere at the equivalent local time. The inset shows the telescopic appearance of Saturn and it's Moons at this time. Click to embiggen.

The Full Moon is Wednesday February 8.

Mars is high in the northern morning sky. After a brief sojourn in the constellation of Virgo, Mars reverses direction and re-enters the constellation of Leo.

Mars has now entered the evening sky, rising around 10 pm (local daylight saving time), but will be relatively low above the late evening horizon for the rest of the week.

Saturn is above the north- eastern horizon, not far from the bright star Spica. Saturn is now high enough in sky in the early morning for telescopic observation.

Mercury is now lost in morning twilight.

Evening sky on Saturday February 4 looking west as seen from Adelaide at 9:00 pm local daylight saving time in South Australia showing Venus in Aquarius, with Jupiter not far away. The insets shows the appearance of Venus and Jupiter and its Moons as seen telescopically at this time. Similar views will be seen elsewhere at the equivalent local time (click to embiggen)

Bright white Venus is readily visible in the evening western twilight sky from around half an hour after sunset for somewhat over an hour and a half.

Venus is in Aquarius this week. It is almost on top of Uranus on the 9th. You will need binoculars to see Uranus, Venus may drown the planet out with its brightness.

Jupiter was at opposition, when it is biggest and brightest as seen from Earth, on Saturday the 29th of October.

However, Jupiter is still a great binocular and telescope object and will be for many weeks to come. Jupiter is visible for most of the night in the north-western sky, setting half an hour after midnight.

In the evening Jupiter is readily visible in the northern-western sky, from about twilight. It is coming closer to Venus, and the pair look very nice in the western evening sky.

Now is a still good time for telescopic observation of this massive world (although the window for observation is narrowing), or follow its moons in binoculars. For good telescopic observation Jupiter is best from 9 pm - 11 pm.

Although Jupiter is the most prominent now, there are lots of interesting things in the sky to view with a telescope. If you don't have a telescope, now is a good time to visit one of your local astronomical societies open nights or the local planetariums.

The evening sky facing North in Adelaide on February 4 at 11:30 pm AEDST showing the waxing Moon about to cover eta Geminorum (indicated by circle). (similar views will be seen from other cities at the equivalent local time eg 11:30 pm ACDST Adelaide.

The nearly full Moon passes in front of the moderately bright star Tejat Prior (eta Geminorium, magnitude 3.5) on the evening of Saturday February 4-Morning Sunday February 5.

The dark limb of the Moon covers the star at 23:38 pm ACDST Adleaide (4th), 0:06 am AEDST Hobart (5th), 0:11 am AEDST Melbourne (5th) and 20:00 pm AWST Perth (4th). The Star will reappear on the bright side of the Moon at 0:13 am ACDST Adleaide (5th), 0:59 am AEDST Hobart (5th), 0:52 am AEDST Melbourne (5th) and 21:00 pm AWST Perth (4th).

With the Moon close to full, this event is really best seen with binoculars or a small telescope. Picking up the stars reappearance will be quite difficult against the brightness of the Moon.

Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pm AEDST. For further details and more information on what's up in the sky, see Southern Skywatch (this will be up dated to February a little later).

Cloud cover predictions can be found at SkippySky.

Another Kayak Adventure

2012-01-29T19:24:00.002+10:30

This time it was a Kayak trip to meet up with the Friends of Torrens Island for a picnic at the historic Quarantine Station.

Great fun and lots of yummy scones were had by all.

It's not every day...

2012-01-28T23:01:00.001+10:30

...you can kayak down your street.

It's a little wet

2012-01-28T20:18:00.000+10:30

Big storm just flooded the street, took out our power.

While we were eating schnitzel

2012-01-27T22:03:00.002+10:30

...Rob McNaught was measuring the orbit of 2012 bx34 using T17, the refined obit from Rob and others helped Goldstone to take radar images of it.

Schnitzel was great though, we were celebrating EldestOnes birthday (he's an odd number old, not a prime number, but the sum of the first and second digits you get an even number which is half MiddleOnes age, and twice the sum of the first and second digits of MiddleOnes age).

Strangely enough, video conferencing on an Android phone doesn't work too well when you are eating dinner.

Carnival of Space #233 is now Here

2012-01-27T08:23:00.000+10:30

Carnival of Space #233 is now Up at Riding with Robots. There's Death Stars, Star factories, the mysterious atmosphere of Titan and much, much more. Pop on over and have a read.

Venus, The Moon and Fireworks, Australia Day 2012

2012-01-26T23:25:00.004+10:30

Had a great Australia Day, lazed around a bit, played Master Labyrinth with the younger boys, swam, had friends over, then walked up to the end of the street to take pictures of Venus, the thin crescent Moon and the Australia Day Fireworks (click on images to embiggen them).

Didn't see C/2003 T12 though, it's probably around magnitude 12.

Comet 2003 T12 recovered in STEREO images

2012-01-25T21:58:00.008+10:30

Comet C/2003 T12 enters the field of view of the STEREO H1B imager on 16-01-2012. Image processed with ImageJ from raw images from SECCHI/STEREO. An animation is at the end of this post.

While my internet was in abeyance, a remarkable story played out in the STEREOHUNTER community.

Comet Al noticed a reasonably bright comet coming out from the Sun and alerted the group, William Thompson back tracked it in the COR2B images.

An orbit was initially worked out by Man-To Hui from the H1B images and Ranier Kracht refined them with the COR2B images, then found that the comets orbit matched that of C/2003 T12 (SOHO-673 observed in C3).

I love this group, the guys are backtracking now to see if they can pick it up in earlier appearances in STEREO, Comet Al may have picked up the 2007 return.

Anyway, the comet will soon be appearing in the evening sky (from about the 26th on it should be high enough above the horizon at astronomical twilight), how bright it will be is a matter of speculation. It might be unaided eye visible, or binocular only (or more likely telescope only). I'll be out having a look as I have the ocean as my western horizon.

If you want to look, Ranier's orbital elements are below:

Ecliptic  Osculating Elements (J2000.0) at JD 2455952.500000  Date:   2012/01/26:00:00:00.00 Body            e        i            w             Node            q                JD-Tp
 CK03T120   0.775932114   11.4780256   217.5091602   176.4741890     0.575542927      -0.4140515

A chart suitable for printing (click to embiggen) showing the track of the comet over the next few days as seen at astronomical twilight in southern Australia. The chart shows the western horizon and the rectangle the field of view of the iTelescope T12 and 14 instruments.

Animation from 16-01-2012 to 17-01-2012 showing comet C/2003 T12 in STEREO H1b, you can just see a faint tail.

Aurora Sky Cam - Go Watch it NOW!

2012-01-25T09:24:00.000+10:30

http://www.auroraskystation.com/live-camera/9/

Aurora happening now (9:24 am ACDST)

So About the Silence

2012-01-25T08:12:00.004+10:30

On Friday evening, shortly after I did Skype Interview with Leslie Hayes, my internet connection crashed. It feebly revived itself once or twice, but basically, while Comet Al has recovered comet C/2003 T12 and aurora roared across the sky, I've been right out of it.

Not that I haven't been busy. I have an article up at The Conversation, I've been the expert adviser for an article in Cosmos, I have an article coming out in next months Australian Sky&Telescope.
And now that the internet is back, I've done a Skype Interview with Francis Walsh and I can at last download all the pictures I've taken with iTelescope.

Of course, now we have EldestOne's birthday to contend with, so don't expect a blizzard of posts.

The Sky This Week - Thursday January 26 to Thursday February 2

2012-01-25T06:28:00.007+10:30

Venus is easily visible in the western evening sky and is visited by the Moon on the 26th and 27th. Jupiter dominates the evening sky in the north-west once Venus has set, and is visited by the Moon on the 30th. Mars enters the evening sky, but is best visible in the morning sky heading towards Saturn, which is near the star Spica.

Morning sky looking east as seen from Adelaide at 3:00 am local daylight saving time on Sunday January 29 showing Mars and Saturn. The inset Similar views will be seen elsewhere at the equivalent local time. The inset shows the appearance of Saturn and it's Moons at this time. Click to embiggen.

The First Quarter Moon is Tuesday January 31. This is the second First Quarter Moon this Month. We might call this a "Blue" First Quarter Moon.

Mars is high in the northern morning sky. After so long in the constellation of Leo, Mars now enters the constellation of Virgo, heading towards Spica and Saturn. Mars has now entered the evening sky, rising around 10 pm (local daylight saving time), but will be relatively low above the late evening horizon for the rest of the week.

Saturn is above the north- eastern horizon, not far from the bright star Spica. Saturn is now high enough in sky in the early morning for telescopic observation.

Mercury is now lost in morning twilight.

Evening sky on Saturday January 27 looking west as seen from Adelaide at 9:00 pm local daylight saving time in South Australia showing Venus in Aquarius, with the crescent Moon beside it and Jupiter not far away. The inset shows the appearance of Venus at this time. Similar views will be seen elsewhere at the equivalent local time (click to embiggen)

Bright white Venus is readily visible in the evening western twilight sky from around half an hour after sunset for somewhat over an hour and a half. Venus is near the thin crescent Moon on the 26th and 27th.

Venus is in Aquarius this week. It is almost on top of phi Aquarii (magnitude 4.2) on the 26th. You will have to wait until quite late in the twilight to see this star appear.

Jupiter was at opposition, when it is biggest and brightest as seen from Earth, on Saturday the 29th of October.

However, Jupiter is still a great binocular and telescope object and will be for many weeks to come. Jupiter is visible for most of the night in the north-western sky, setting half an hour after midnight.

Evening sky on Monday January 30 looking north as seen from Adelaide at 9:00 pm local daylight saving time in South Australia showing Jupiter and the waxing Moon. Similar views will be seen elsewhere at the equivalent local time. INSET: Jupiter and its Moons as seen telescopically at this time, (click to embiggen)

In the evening Jupiter is readily visible in the northern-western sky, from about twilight. It is coming closer to Venus, and the pair look very nice in the western evening sky.

Now is a still good time for telescopic observation of this massive world (although the window for observation is narrowing), or follow its moons in binoculars. For good telescopic observation Jupiter is best from 9 pm - 11 pm.

Although Jupiter is the most prominent now, there are lots of interesting things in the sky to view with a telescope. If you don't have a telescope, now is a good time to visit one of your local astronomical societies open nights or the local planetariums.

Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pm AEDST. For further details and more information on what's up in the sky, see Southern Skywatch (this will be up dated to February a little later).

Cloud cover predictions can be found at SkippySky.

An Ordinary Day for the Astroblogger

2012-01-23T06:59:00.004+10:30

During the incident where my images were appropriated and faked (see here, here and here), one of the more amusing incidents was when Don Gilson claimed that the fake planet was in my originals, but I had removed it under threat of the Queen and the CIA.

So this cartoon almost immediately came to mind (of course you have to click to embiggen for it to be legible, and of course it is copyleft me, 2012).

Why ponies? [shrugs] Why the Queen?

A Re-analysis of My Comet 103P Images (and the original FITS files)

2012-01-18T21:48:00.007+10:30

UPDATE: Fixed munged file links, now you can download all files, not just the third one (rolls eyes).

As you may know, one of my comet images has been taken and modified to give the appearance that there is an unknown planet in it (see here and here for details and a bunch of free resources to play with).

It's been 2 years since I first processed this image, and I've learnt a few tricks since then. S0 I went back and re-analysed them.

This time I stretched the images in FITS Liberator (Arcsin stretch), saved as TIFF, stacked the TIF's in ImageJ, registered the images, then used a Z project to SUM the stack. After this I used a square root transform to bring out the fainter details.

Click to embiggen the image (comet 103P Hartley2, and PGC 7154, taken on 18-09-2010), and compare it with my original stack.

I've been able to bring out the comets tail without over exposing the head, like last time. The galaxy PGC 71451 is more disappointing, but I haven't fiddled with the contrast to really bring it out.

One thing that is definitely NOT there is a crescent planet. You can even see the enhanced star diffraction spike running right through where the planet was later pasted in.

If anyone else wants to play with the raw FITS files, you can access them here (warning each file 3.5 Mb zip archives)
File 1
File 2
File 3
File 4
Process away, but do acknowledge where you got them from.

Oh and here is the header file, which you can extract from the original FITS files with any suitable image processing program:
SIMPLE = T
BITPIX = 16 /8 unsigned int, 16 & 32 int, -32 & -64 real
NAXIS = 2 /number of axes
NAXIS1 = 2184 /fastest changing axis
NAXIS2 = 1472 /next to fastest changing axis
BSCALE = 1.0000000000000000 /physical = BZERO + BSCALE*array_value
BZERO = 32768.000000000000 /physical = BZERO + BSCALE*array_value
OBJECT = '103P_18-09-0' / Target object name
TELESCOP= 'ACP->GRAS-005 TAK E250' / Telescope name
INSTRUME= 'SBIG ST-10 3 CCD Camera' / Detector instrument name
OBSERVER= 'Ian Musgrave' / Observer name
NOTES = ' '
DATE-OBS= '2010-09-18T08:04:03' / [ISO 8601] UTC date/time of exposure start
[snip lines if guff]
HISTORY File was processed by PinPoint 5.0.14 at 2010-09-18T08:05:56
DATE = '18/09/10' / [old format] UTC date of exposure start
TIME-OBS= '08:04:03' / [old format] UTC time of exposure start
UT = '08:04:03' / [old format] UTC time of exposure start
TIMESYS = 'UTC ' / Default time system
RADECSYS= 'FK5 ' / Equatorial coordinate system
AIRMASS = 1.07641649772E+000 / Airmass (multiple of zenithal airmass)
ST = '00 52 23.96' / Local apparent sidereal time of exp. start
LAT-OBS = 3.29035555556E+001 / [deg +N WGS84] Geodetic latitude
LONG-OBS= -1.05528305556E+002 / [deg +E WGS84] Geodetic longitude
ALT-OBS = 2.25000000000E+003 / [metres] Altitude above mean sea level
OBSERVAT= 'G5 - The Stefano Padovan Wide-Field Observatory' / Observatory name
RA = '23 25 01.19' / [hms J2000] Target right ascension
OBJCTRA = '23 25 01.19' / [hms J2000] Target right ascension
DEC = '+47 29 19.8' / [dms +N J2000] Target declination
OBJCTDEC= '+47 29 19.8' / [dms +N J2000] Target declination
CLRBAND = 'R ' / [J-C std] Std. color band of image or C=Color
END

Carnival of Space #232 is here.

2012-01-17T23:02:00.002+10:30

Carnival of Space #232 is now up at Vintage Space. There's the space station avoiding collisions, Earth-like planets galore, exomoons, the first supernova of 2012 and much more. Head on over for a read.

Just a Reminder about the Globe at Night Light Pollution Survey

2012-01-17T22:46:00.003+10:30

Northern sky at 10 pm local daylight saving time in Australia showing Orion.

Globe at Night, the international light pollution survey, is currently running until January 23. The Survey is running four times this year, with January 14-23 followed by February 12-21, March 13-22 and April 11-20. Visit their websit e for easy to follow instructions and charts to estimate how dark your sky is.

Basically, an hour or so after sunset (8-10 pm) head out, look to the north to find Leo, (if you are in the northern hemisphere) or south to find Crux (for us southern hemisphere types) or Orion (for everybody) then check how many stars are visible, and report your observations. It's a great excuse to get outdoors and look at the sky. You might even see the International Space Station or an Iridium flare.

This year you can submit your results a smart phone or tablet. To do this, you can use the web application at www.globeatnight.org/webapp/. Globe at Night is also on Facebook and Twitter.

The Sky This Week - Thursday January 19 to Thursday January 26

2012-01-17T20:25:00.007+10:30

The New Moon is Monday January 23. Venus is easily visible in the western evening sky and is visited by the Moon on the 26th. Jupiter dominates the evening sky in the north-west once Venus has set. Mars enetrs the evening sky, but is best visible in the morning sky heading towards Saturn, which is near the star Spica. Globe at Night Light Pollution Survey now on.

Morning sky looking east as seen from Adelaide at 3:00 am local daylight saving time on Sunday January 22 showing Mars and Saturn. The inset Similar views will be seen elsewhere at the equivalent local time. The inset shows the appearance of Saturn and it's Moons at this time. Click to embiggen.

The New Moon is Monday January 23. The Globe at Night, international light pollution survey, is January 14-23 followed by February 12-21, March 13-22 and April 11-20.

Mars is high in the northern morning sky. After so long in the constellation of Leo, Mars now enters the constellation of Virgo, heading towards Spica and Saturn. Mars has now entered the evening sky, rising around 11 pm (local daylight saving time), but will be low above the late evening horizon for the rest of the week.

Saturn is above the north- eastern horizon, not far from the bright star Spica. Saturn is now high enough in sky in the early morning for telescopic observation.

Mercury is now lost in morning twilight.

Evening sky on Saturday January 26 looking west as seen from Adelaide at 9:00 pm local daylight saving time in South Australia showing Venus in Aquarius, with the crescent Moon below and Jupiter not far away. The iset shows the appearance of Venus at this time. Similar views will be seen elsewhere at the equivalent local time (click to embiggen)

Bright white Venus is readily visible in the evening western twilight sky from around half an hour after sunset for somewhat over an hour and a half. Venus is in Aquarius this week. It passes lambda Aquarii (magnitude 3.8) on the 23rd and 24th. You will have to wait until quite late in the twilight to see this star appear.

Jupiter was at opposition, when it is biggest and brightest as seen from Earth, on Saturday the 29th of October.

However, Jupiter is still a great binocular and telescope object and will be for many weeks to come. Jupiter is visible for most of the night in the north-western sky, setting half an hour after midnight.

Evening sky on Saturday January 21 looking north as seen from Adelaide at 10:00 pm local daylight saving time in South Australia showing Jupiter and the waxing Moon. Similar views will be seen elsewhere at the equivalent local time. INSET: Jupiter and its Moons as seen telescopically at this time, (click to embiggen)

In the evening Jupiter is readily visible in the northern sky, from about twilight, and the north-western sky when it is fully dark.

Now is a good time for telescopic observation of this massive world, or follow its moons in binoculars. For good telescopic observation Jupiter is best from 9 pm - 11 pm.

Although Jupiter is the most prominent now, there are lots of interesting things in the sky to view with a telescope. If you don't have a telescope, now is a good time to visit one of your local astronomical societies open nights or the local planetariums.

Comet Lovejoy will be very difficult to spot as it has faded significantly, you need very serious telescopic kit to see it now..

Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pm AEDST. For further details and more information on what's up in the sky, see Southern Skywatch (this will be up dated to January a little later).

Cloud cover predictions can be found at SkippySky.

What Can We Learn from the Fake HMO Image Incident?

2012-01-16T22:54:00.013+10:30

Image purported to be of a large object near 89 Leo, allegedly taken on January 9, 2012 using the GRAS (now iTelescope) scopes. The alleged coordinates are RA 11 34 21 DEC 03 03 35, click on image to embiggen for detail. However, it is a photshopped copy of one of my images from 18 September 2010.

As you may know, one of my images of comet 103P (Hartely 2) has been taken, had a fake planet added to it, and the doctored image has been circulating as evidence of Nibiru (or at least a Heavy Mass Object, whatever that is). Now, while I’m annoyed that someone has fraudulently modified one of my images, I’m more interested in using this as a teachable moment.

What lessons can we learn from this, and what resources are there for people to learn about the sky and help them interpret images posted on the web?

Before we start, here’s a list of freeware programs you can use in our exploration of astronomical images on the net:

GIMP Free image processing program
Celestia 3D Solar Simulation program
Stellarium Planetarium program
Cartes du Ciel Free sky charting software
WikiSky
Astrometry.net Astronomy image analysis prgram
Aerith Comet location and information
Minor Planet Center Comet and Asteroid Ephemeris

Part 1: How can we tell the Image of the purported Heavy Mass Object/Nibiru is a fake.

Evaluating images takes some degree of astronomical knowledge and some degree of experience with astrophotography, but I’m going to start with some simple clues that you can get with very basic knowledgee of the solar system. First off, let’s look at the image circulating on the web that claims to be of 89 Leo with a planetary object in it (image at the head of the post, click to embiggen).

With no knowledge of where or when the image was taken (or of the fact that it is a Photoshopped version of one of my images), what clues are there that this is a fake:

First Clue to Fakery: The object is a crescent. I’ve already alluded to this in my previous post, but to re-iterate, this object is supposed to be outside Earth’s orbit. It is impossible for an object outside Earth’s orbit to show a crescent. See the diagram just above, to visualise this.

Second Clue to Fakery: Have a look at the image to the left (it's my original image, it's also in the image at the head of the post), see the long fuzzy blob there, that’s a comet.

The comet’s image has trailed as when you take long exposures, things like comets, asteroids and planets move with respect to the background stars. In this case, I actually took 4x90 second images and stacked them up to improve the brightness, because I aligned all the images so that the stars were in focus, the comet shows as a trail, you can see here where I have stacked the same batch of images on the comet rather than the stars the comet is clear and the stars are trailed (but for the purposes, we don’t need to know that at the moment).

Looking back to the comet you can see the faint tail pointing off to the bottom. Now, one of the important things about comets is that the tail points away from the Sun. With the dust tails things are slightly more complex, as the tail curves, and if the comet is directly in Earth’s orbital plane the comet can hide the dust tail, (see here for a complex tail of comet 2009 P1 Garradd), but the point is that the tail will not be pointing AT the Sun.

Relationship of the orbit of comet 103P Hartley 2 with regard to the Earth and the Sun. 103P is outside and above Earth's orbit, so any object near 103P in the T05 imager must be outside Earth;'s orbit and hence not a crescent. Simulation in Celestia, click to embiggen.

Why is this important? Because look at the crescent object. The Sunlight must be coming from the bottom left to illuminate the object to give it a crescent shape.

But the comets tail means that the Sun must be towards the top right. The crescent object has been pasted in without any regard to the Sun’s location. You can use Celestia, and this set of elements for 103P, to play with the comets orbit to demonstrate this to your satisfaction.

Still another clue comes from the object being a crescent. As we saw above, the crescent is facing the wrong way with regard to the Sun, but it is also too far away from the Sun. Thin crescents as seen in the doctored image (and crescent Mercury, crescent Venus and the Crescent Moon), can only show up when the body in question is nearly between us and the Sun.

The thin crescent moon can be as far away as 25 degrees, Venus 23 degrees. However, this object is fully 115 degrees from the Sun on 9 January (if it was actually near 89 Leo, it's a bit further way using the real location) , which would mean it could not be a crescent. Thus it cannot be an actual object, but something pasted in later (here's an example of my animations of the phases of Venus).

Third Clue to Fakery: As mentioned above, when taking long exposures (6 minutes in this case), solar system object are trailed because they move with respect to the distant stars. The comet has trailed out into a rod shape because of this movement. Now look at the crescent, it is crisp without any trailing. Any solar system object closer than Neptune will show significant trailing (and even Neptune will show some trailing). So this can’t be an image of an actual solar system object, but a pasted in image.

103P Hartley as viewed against the background constellations on 18 September 2010, as seen form Earth. Simulated in Celestia (click to embiggen)

Those are all fairly simple ways you can check that an image is fake with relatively little astronomical knowledge. Let’s look at some ways to check that require a bit more expertise.

Is the Image actually in Leo? The text on the image purporting to show the alleged HMO states that the image was taken of 89 Leo on the 9th of January, 2012. How can we check this? Well, aside from the fact that it is identical to an image I posted on the 20th of September 2010 (apart from the added crescent object), we can use a number of clues. Once again, the comet is our guide.

The area around PGC 71451, as seen in WikiSky (left) and from my image of 18-09-2010 (which is identical to the image claimed to be from 9 January 2012, except for the added crescent object). The boxes surround PGC 71451 in both images. You can see that my image (and by extension the photoshopped image) is identical to the Wikisky field. I've had to rotate my image slightly to match the orientation in WikiSky. Click to embiggen.

First, head over to Seiichi Yoshida's Aerit h (or cometography), and look at the list of bright observable comets. Note that there are no comets in Leo at the moment. So the image can’t be in Leo. So where is it?

Next head over to Astrometry.net. I usually use Astrometry.net for identifying fields in the STEREO spacecraft imager, but you can use it to identify other astrophotos as well. You will need to login using your Google or Facebook ID, upload the original image (restricting the search to Leo otherwise the run will take 24-48 hours), and you will get no matches. Run it again restricting to Andromeda, and it will match to the section of Andromeda where the galaxy PGC 71451 is. It’s not an image taken in Leo.

Astrometry.net run demonstrating that the image is taken in Andromeda, not Leo. Click to embiggen.

Another clue is that on the 9th of January, the nearly full Moon was 60 degrees from 89 Leo. Any long exposures taken this close to the full Moon would be badly affected by moonlight, but this image is not contaminated with moonlight (see my image of the supernova in Leo taken on 10 January for how it would look).

Is it where I say it is (in Andromeda)? Well, we’ve already used Astrometry.net to locate the area, and WikiSky as well to confirm that it is indeed an image taken with PGC 71451 in it. Can we double check.

Yes, but the next bit is a bit more tricky. You will need a decent astronomy charting program which can allow you to add other bodies like comets (such as Cartes du Ceil), then head over to the Minor Planet Center, and generate an Ephemeris for 103P (Hartley 2) for 18 September 2010 by typing 103P into the entry box, add the coordinates to your charting program (the MPPEC gives a list of programs it can expert directly to) and Hey Presto! You will see 103P near PGC 71451, just as in my image. You can also use Stellarium, but you will need to download the pack of extra stars, or the images won’t match up. Because 103P is no longer bright, you will need to specially import the 1 line MPEC elements for 103P into Stellarium for it to show up.

Difference overlay of my image and the image allegedly in 89 Leon using the GIMP. (click to enlarge)

You can also use the GIMP (which I use a lot for astrophotography), to overlay my image and the doctored image. You can overlay them and use the difference command in overlay mode to show up differences. Note that the vast majority of the image is nulled out, except the added labels and (although this is a bit hard to see, so you will need to embiggen) the crescent object.

The comet is critical here as well. If this was someone else's image, the comet would have been in a slightly different part of the image, and not nulled out as it is here.

Summary: We have now demonstrated that-

a) The image purportedly of 89 Leo on 9 January 2012 is a copy of my image of of the comet 103P taken on 18-09-2010 near PGC 71451 in Leo.

b) The crescent object is a pasted in fake.

Part 2: What do I do now.

This was a bit exhaustive (and exhausting), but it’s shown how you can use several clues to determine if an image is faked. Of course, not all images claiming to be extraordinary events are faked, often they are simple mis-identification of things such as jet contrails, internal camera or telescope reflections, Venus and other bright stars taken out of focus and so on. But using the same principles (where was the image taken, how do solar system bodies line up) you can work out if what is being presented is something startling, or much more mundane.

Hot pixels seen in my and the doctored image that Don Gilson claims is a "structure". Left panel, hot pixels when the image is stacked on the stars, right image hot pixels when image stacked on the comet.

For example, in his youtube video dealing with the image, Don Gilson makes much of a series of dots in one part of the image, claiming it is a “structure”, but it’s just a series of hot pixels (pixels in the CCD chip in the camera that are jammed permanently on).

Because the image is constructed from a stack of 4 individual 90 second exposures, (re-calibrated between each exposure), the stars drift slightly between the exposures, so the hot pixels are not in the same place (in the companion image, constructed by stacking the frames on the comet, rather than the stars, the hot pixels trail horizontally). I also did a second image stacking the same frames on the comet, and you can see the pixels trail differently.

Hot pixels are the bane of astrophotographers (not only do they mess up pretty shots, they can be mistaken for asteroids), and there are a few groups of then in the image. However, you have to have a bit of experience with CCD astrophotography to recognise hot pixels.

With programs like Stellarium and Cartes du Ceil you can work out what you are looking at, Celestia allows you to simulate planetary systems and events. Using these is a lot of fun, and you will learn a lot about the sky and solar system while you are at it.

Phobs Grunt has Come Down

2012-01-16T07:21:00.002+10:30

Phobos Grunt Re-enterd the Earth's atmosphere early this morning (Australia time). While there was initially some confusion as to where it came down, official reports say it came down at 17:45 UTC, 1250 km west of Wellington Island, Chile. See map here and interesting info graphic here.

Phobos Grunt Updated Predictions

2012-01-15T17:41:00.003+10:30

While still having very large error bars, the predictions for the Phobos Grunt reentry are becoming more certain.

Most predictions are still for 15 January UT, roughly around 20 h UT but with spreads of error on the order of 9 hours to one and a half hours (see here, here, here and here for a variety of predictions). The tightest prediction now puts the re-entry off the coast of Africa.

From Australia's point of view, the spacecraft will come down sometime on early Monday 16th, CalSky (and the Phobos Grunt site) has a pass over Adelaide at 6:54 am AEDST, with reentry at 7:12 AEDST +/- 3 hours. So it may be possible for Australians to see the craft-reenter.

Phobos Grunt comes Down this Weekend

2012-01-13T22:52:00.004+10:30

UPDATE: The latest CalSky update hasPhobos Grunt coming over Adeliade on the 16th at 5:57 local ( not daylight saving) time, with atmospheric re-entry at 11:07 local time. Obviously this is a rapidly evolving situation, so keep an eye on the websites.

The doomed Russian Mars probe, Phobos Grunt, will re-enter the Earth's atmosphere sometime this weekend, the predictions are for 15 January UT, but with wide spreads of error on the order of half a day (see here, here, here and here for a variety of predictions). The tightest prediction puts the re-entry somewhere over Mongolia.

From Australia's point of view, the spacecraft will come down sometime in the early hours of Monday 16th, but none of the Satellite tracks pass over Australia in the next few days.

Here's a radar image of Phobos Grunt (Via Jayne Stigger)

Southern Skywatch January 2012 Edition Up

2012-01-13T21:55:00.003+10:30

Evening sky looking westh as seen from Adelaide at 21:00 pm local daylight saving time on Thursday January 26 showing Venus near the crescent Moon. Similar views will be seen elsewhere at the equivalent local time. Click to embiggen.

The January edition of Southern Skywatch is now up.

Venus is prominent in the evening sky and is close to the crescent Moon on the 26th.

Mars enters the evening sky and is close to the Moon on the 13th and 14th. Jupiter is prominent in the evening sky, and is still a good telescopic object in the early evening.

Saturn is in the morning sky and is close to the Moon on the 17th.

Mercury leaves the morning sky and will return to the evening sky next month.

In Which I (Fail to) Discover Nibiru: Or Fakery is Flattery

2012-01-13T10:28:00.009+10:30

Image purported to be of a large object near 89 Leo, allegedly taken on January 9, 2012 using the GRAS (now iTelescope) scopes. The alleged coordinates are RA 11 34 21 DEC 03 03 35, click on image to embiggen for detail.

This image, which is claimed to show the mythical planet Nibiru (or HMO, for Heavy Mass Object), started doing the rounds recently. I became aware of it yesterday, in a Facebook post and briefly pointed out why it had to be a fake.

The purported object is a crescent, yet is supposed to be outside of Earth's orbit, it is impossible for any object outside of Earth's orbit to be a crescent. To be a crescent, the object must be nearly between us and the Sun (try this out with a torch and two tennis balls to confirm it for yourself).

Also, the crescent image has been Photo-shopped in, you can see a difference between the resolution of the object and that of the stars.

But what I hadn't realised is that the image that was Photo-shopped was one of mine.

This image is the result of a stack of 4 x 90 second images of 103P in Andromeda, near the faint he galaxy PGC 71451. Images taken with GRAS 05 on 18-09-2010 stacked and summed on the stars using ImageJ (click to on the image embiggen). The original image is here .

I paid no more attention to the thread (playing with my nephews and watching Startrek had a higher priority than debunking alleged Niburu sightings). However, while I was sleeping, folks in the US were tracking down the the image.

Francis Walsh noticed that the image didn't look like images of 89 Leo he had taken (you can use wikisky to compare the image to the region around 89 Leo and the image), and Messierhunter noticed the fuzzy object to the left was a comet, a comet he had imaged called 103P, he then tracked down to image, which turned out to be one of mine.

Tbar1984 then created a video pointing out the fake. All while I was peacefully sleeping.

Side by side comparison of my image from 18-09-2010 (right panel) and the image allegedly taken on 09-01-2012 (left panel. Click to embiggen.

This is a side by side comparison of the two images, the one allegedly taken on 9-01-2012 and mine taken on 18-09-2012. you can see that they are identical. Comet 103P is the killer, comet 103P is not near Leo in 2012, and infact is too dim now (around magnitude 19), to be imaged in all but the most serious iTelescope research scopes, and this image is clearly taken with GRAS05 (the scaling and intensity of the stars is the clue, GRAS 11 now T11, for example, has a very different scaling and photometric response).

It's painful listening to Don Adams try and pretend it is not a fake (especially when he points to what are clearly stars and calls them ships). Folks, you just can't randomly point to a few stars and claim a match, lots of stars will form tetrahedron like alignments, you have to do precise astrometry. What you should do is use Overlay with Difference setting in Photoshop/GIMP to see if the stars align properly.

I have no idea who faked the image by Photo-shopping my original (Don Adams says it came from a "trusted source"), but I suppose I should be flattered that they chose my image as a good example of GRAS imagery. Validates me as an astrophotographer it does.

Apparently rumours are circulating on the web that I have faked MY image, taking the image and blocking out the alleged object. Unfortunately for them, I have the original images and FITS (also, I'm not that good a photoshopper to be able to remove the text from the alleged image without removing the stars the text overlies).

Should be interesting to see what develops over the next few days, but I have no illusions that the Nibiru fans will be dissuaded by mere evidence.

UPDATE: hat tip to Scott Ferguson, who emailed me last night, but I completely ignored the intertubes last night.

Comet 49P amongst the Galaxies

2012-01-11T22:52:00.003+10:30

Comet 49P taken with the iTelescope T14 instrument in Mayhill New Mexico. I took 10 x 120 second image. Top Left: Images images stacked on the stars using ImageJ, and the stack Summed using Z project. After that I did a square root process to clean up the background a bit, then cropped down to make the comet (bottom left of centre) easier to see. Top Right: As above but entire field. Bottom Left: Galaxies identified by Astrometry.net . Click on any image to embiggen.

Comet 49P is currently in a field very rich in some iconic galaxies, sadly, the waxing Moon is not far away either. Here I've used the widefield T14 instrument to get a good feel for the spectacular field the comet is in. The comet is a faintish magnitude 14, and moves sufficiently that it doesn't stack, and is smeared out and faint. Still if you embiggen the top left image it looks pretty nice.

I probably have to wait until the 19th for the Moon to wane sufficiently to get any more images of this comet.

Possible Supernova in NGC 3239 in Leo

2012-01-11T00:01:00.005+10:30

My image of the possible supernova in NGC 3239 in Leo taken with iTelescope T05 (3x120 seconds, stacked in ImageJ). Compare this to the discovery image (more details at the link as well) and an image taken before the supernova (tip of the hat to Charles Bell).

The image is very badly affected by the Moonlight, with the Moon only 30 degrees away, and it will only get worse over the next few days. Not sure how I'll get any good magnitude estimates out of this.

Comet C/2010 G2 Hill in STEREO

2012-01-10T19:00:00.000+10:30

Left: Comet C/2010 G2 Hill in the STEREO H1A imager on 5-01-2102. Top Right: Comet C/2010 G2 Hill in the STEREO H1A imager on 6-01-2102. Images tacked, background subtracted and contrast enhanced after square root modification in ImageJ. Click on images to embigen. An animation of the comet from the 6th where a tiny tail can just be seen is below.

Comet C/2010 G2 Hill was picked up in the STEREO H1A imager by Jiangao Ruan and identified by Wen-Tao Hsu and Comet Al. The comet had been reported to be in outburst on the 3rd.

For those interested, I attempted to measure the intensity of C/2010 G2 Hill using images from the STEREO spacecraft, the comet came into view in the STEREO H1a instrument on 4 Jan, but was not in such a good position for attempted astrometry until the 5th.

My astrometry of C/2010 G2 Hill from 5-Jan to 7-Jan yields a magnitude of 12.1 for all days.

It's pretty hard to get decent values as the comet is very close to brighter stars and right close to the limit of detection (mag 13). I also can't work out accurately the 95% confidence interval for these values (but its on the order of +/- 1).

The magnitudes were generated by measuring the intensities of the comet and nearby reference stars in ImageJ then generating a standard curve from the reference stars in Graphpad prism, and interpolating the intensity of the comet from this curve (yes, I know this is rubbish, but it's what I have to work with). Reference stars are
Star Magnitude
TYC 660-105-1 8.45
TYC 660-293-1 9.81
TYC 660-877-1 10.93
TYC 660-48-1 11.22
TYC 660-579-1 11.8
TYC 660-944-1 12.57

Animation of C/2010 G2 Hill on the 6th, a small tail may just be seen. the image has been inverted from B7W to make seeing the comet clearer (uses images above to see location).

The Sky This Week - Thursday January 12 to Thursday January 19

2012-01-10T15:22:00.008+10:30

The Last Quarter Moon is Monday January 16. Venus is easily visible in the western evening sky. Jupiter dominates the evening sky in the north-west once Venus has set. Mars is visible in the morning sky heading towards Saturn, which is near the star Spica. The waning Moon is near Mars on the 13th and 14th and near Saturn on the 17th. Mercury is lost in the morning twilight.

Morning sky looking east as seen from Adelaide at 5:00 am local daylight saving time on Tuesday January 17 showing Mars, Saturn and Mercury. Similar views will be seen elsewhere at the equivalent local time. Click to embiggen.

The Last Quarter Moon is Monday January 16.

Mars is high in the northern morning sky. After so long in the constellation of Leo, Mars now enters the constellation of Virgo, heading towards Spica and Saturn. The waning Moon is near Mars on the mornings of Friday the 13th and Saturday the 14th.

Saturn is above the north- eastern horizon, not far from the bright star Spica. On Tuesday the 17th, Saturn, Spica and the waning Moon are close together, making an attractive triangle.

Mercury is now lost in morning twilight.

Evening sky on Saturday January 14 looking west as seen from Adelaide at 9:00 pm local daylight saving time in South Australia showing Venus in Aquarius. Similar views will be seen elsewhere at the equivalent local time (click to embiggen)

Bright white Venus is readily visible in the evening western twilight sky from around half an hour after sunset for somewhat over an hour and a half. Venus leaves Capricornius this week, entering Aquarius. It passes iota Aquarii (magnitude 4.8) on the 12th. You will have to wait until quite late in the twilight to see these stars appear.

Jupiter was at opposition, when it is biggest and brightest as seen from Earth, on Saturday the 29th of October.

However, Jupiter is still a great binocular and telescope object and will be for many weeks to come. Jupiter is visible for most of the night in the north-western sky, setting half an hour after midnight.

Evening sky on Saturday January 14 looking north as seen from Adelaide at 10:00 pm local daylight saving time in South Australia showing Jupiter and the waxing Moon. Similar views will be seen elsewhere at the equivalent local time. INSET: Jupiter and its Moons as seen telescopically at this time, (click to embiggen)

In the evening Jupiter is readily visible in the northern sky, from about twilight, and the north-western sky when it is fully dark.

Now is a good time for telescopic observation of this massive world, or follow its moons in binoculars. For good telescopic observation Jupiter is best from 9 pm - 12 am.

Although Jupiter is the most prominent now, there are lots of interesting things in the sky to view with a telescope. If you don't have a telescope, now is a good time to visit one of your local astronomical societies open nights or the local planetariums.

Comet Lovejoy will be very difficult to spot due to the Moonlight until next week.

Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pm AEDST. For further details and more information on what's up in the sky, see Southern Skywatch (this will be up dated to January a little later).

Cloud cover predictions can be found at SkippySky.

Globe at Night Starts January 14

2012-01-09T01:57:00.002+10:30

Globe at Night, the international light pollution survey, is running four times this year. The first survey is January 14-23 followed by February 12-21, March 13-22 and April 11-20.

You can learn more and get charts and instruction at their websit e. There is also a 365 Days of Astronomy Podcast: GLOBE at Night Kickoff: Seeing the Light.

Still More Comet C/2011 W3 Lovejoy Goodness

2012-01-09T01:12:00.003+10:30

Rob Kaufman's exquisite series of photos and animations
https://sites.google.com/site/robsastropics/comets/comet-c-2011-w3-lovejoy
Stuart Thomson's great images from Victoria
http://www.siriuscybernetics.org.au/Siriuscybernetics/Lovejoy120102.html
And the fantastic animation, 6 days of Lovejoy, from Phil Hart
http://vimeo.com/34639569

I really have to finish processing my comet Lovejoy images.

Comet C/2009 P1 Garradd - G20, G14 January 5, 2012

2012-01-09T00:25:00.002+10:30

Comet C/2009 P1 Garrad taken with the iTelescope T20 colour instrument and the T14 instrument in Mayhill New Mexico on 5 January. I took 3 x 300 second images for T20,and 5 x 120 second images for the T14 instrument. Left: T14 Images stretched individually in FITS Liberator with Arcsinh (Arcsinh x) and auto scaling. Stretched images then stacked on the comet using ImageJ, and the stack Summed using Z project. After that I did a square root process to clean up the background a bit. Top Right: T20 Images converted to RBG using ImageJ, stacked on the comet and the stack Summed using Z project. Click on images to embigen (you will need to to see the ion tail details, especially in colour.

The B&W T14 image stack turned out very nicely, with the ion tail clearly defined. The T20 colour image is muddy and shows poor detail (image cropped and rotated to matche the orientaion of the T14 instrument). I'm obviously doing SOMETHING wrong in processing, the JPEG preview thumbnails show the ion tail more clearly.

Is this a Meteor in Titan's atmosphere

2012-01-07T12:28:00.004+10:30

Image credit NASA/JPL/Space Science Institute

The bright steak on this image was originally thought to be a cosmic ray artefact, but is now being considered as a possible meteor in Titan's upper atmosphere (still trying to find confirmation of this, found via twitter).

In Which I Welcome Rain

2012-01-07T12:20:00.003+10:30

Clouded out here (which means that the southern iTelescopes are clouded out too, so no comet Lovejoy). However, the Bettdeckererschnappender Weisle is acting as a Media Liaison officer for the Country Fire Service up in Port Augusta, updating information about the Flinders Ranges fires, which threaten the community of Willunga. the rain has reduced the threat, and she might get home by the end of the weekend. So I am REALLY glad of the rain.

I'm Nominated in the Shorty Awards

2012-01-07T12:13:00.002+10:30

I've been nominated for a Shorty Award in the Science Category. It's apparently the Oscar equivalent of the tweet world. You vote by tweeting, and you can apparently vote for more than one person. There are other, far more deserving astronomers out there to vote for, so why not head off and vote.

Comet C/2009 P1 Garradd - G20 January 4, 2012

2012-01-07T10:12:00.003+10:30

Comet C/2009 P1 Garrad taken with the iTelescope T20 colour instrument in Mayhill New Mexico on 4 January. I took 2 x 300 second images, each panel is a separate treatment of the images. Top Left: Images converted to RBG using ImageJ, stacked on the comet and the stack Summed using Z project. Top Right: JPEG preview image. Click on images to embigen.

My attempt at a colour image using T20, as you can see, I suck badly at colour composition, the preview image is better than my processed ones. Everything I tried to make the images better only made them worse. Does this mean I have to purchase MaximimDL after all :-(

Roland Ligustri's shot from yesterday using the T20 colour instrument is here.

Unexpected Mobile Rainbows yet again

2012-01-06T17:48:00.000+10:30

A 28 degree solar halo seen from our backyard. Although beautiful, it means no comet Lovejoy via iTelescope.

Images of the Doomed Phobos-Grunt Spacecraft from Earth

2012-01-06T00:58:00.003+10:30

Image copyright Theirry Legault.

Theirry Legault does it again, with another amazing image of a satellite/spacecraft taken with an earthbound telescope. This is as significant a technical feat as it is beautiful.

See his Phobos Grunt site for the full size image and a great video of the spacecraft coming over. And check out his main site for more amazing satellite/spacecraft photography.

Phobos-Grunt may re-enter around January 15th.

Tip of the spacevisor to the BadAstronomer.

Comet C/2009 P1 Garradd - January 4, 2012

2012-01-05T22:53:00.003+10:30

Comet C/2009 P1 Garrad taken with the iTelescope T14 instrument in Mayhill New Mexico. I took 5 x 90 second images, each panel is a separate treatment of the images. Top Left: Images stretched individually in FITS Liberator with Arcsin x(Arcsin x) and autobalance. Stretched images then stacked on the comet using ImageJ, and the stack Summed using Z project. After that I did a square root process to clean up the background a bit. Top Right: Images stretched individually in FITS Liberator with Arcsin x(Arcsin x) and autobalance. Stretched images then stacked on the stars using ImageJ, and the stack Summed using Z project. After that I did a square root process to clean up the background a bit. Bottom Left: Raw Images stacked on the stars using ImageJ, and the stack Summed using Z project. After that I did a square root process. Click on any image to embiggen.

The comet looks very impressive now, the right tail is the dust tail, and the top tail is the ion tail (the bottom image is inverted). The comet is now in part of its orbit where the tails are very widely separated. The images were spoiled a little by the advent of twilight, as the comet gets higher in the morning sky it should look better. Australians have to wait a couple of moths before it appears in our sky again.

Roland Ligustri's shot about the same time using the T20 colour instrument is here. For some earlier images of Garradd, see here (scroll down a lot).

Carnival of Space #230 is here.

2012-01-05T17:09:00.002+10:30

Carnival of Space #230 is now up at Cheap Astronomy. And there's a podcast! There's things dropping from the sky, more exoplanets, naming supernovae and more. Hop on over and have a read.

Global-Rent-a-Scope becomes iTelescope

2012-01-04T14:48:00.004+10:30

Global Rent a Scope, the remote telescope group that I subscribe to and also blog with, have now become iTelescope. This involves a significant upgrading and improvement of the site, scopes and systems (and an improved billing system), with the Australian scopes moving to the iconic Siding Springs Observatories (and some great new scopes joining them). You can read about the changes here.This is a very exciting time and I'm looking forward to my first images via iTelescope. My iTelescope Alerts blog will now be found here.

A Gallery of Comet Lovejoy Images

2012-01-04T11:11:00.003+10:30

While I'm still processing my own Comet C/2011 W3 images, here a link to a gallery of stunning images from the comet section of the Astronomical Society of Victoria. Thumbnails here, main gallery here.

The Sky This Week - Thursday January 5 to Thursday January 12

2012-01-04T08:31:00.004+10:30

The Full Moon is Monday January 9. Venus is easily visible in the western evening sky. Jupiter dominates the evening sky in the north-west once Venus has set. Mars is visible in the morning sky heading towards Saturn, which is near the star Spica. Mercury is very good in the morning near the horizon. Comet Lovejoy is now only visible in binoculars and telescopes. Earth is at Perihelion on the 5th.

Morning sky looking east as seen from Adelaide at 5:00 am local daylight saving time on Saturday January 7 showing Saturn and Mercury. Similar views will be seen elsewhere at the equivalent local time. Click to embiggen.

The Full Moon is Monday January 9.

Mars is high in the northern morning sky, in the constellation of Leo. It is heading towards Spica and Saturn.

Saturn is above the north- eastern horizon, not far from the bright star Spica.

Mercury appears low in the morning twilight above the eastern horizon, below the constellation of the Scorpion. You will need a reasonably, clear eastern horizon to see it. This is the last week the Mercury can be easily seen this month.

Evening sky on Tuesday December 27 looking west as seen from Adelaide at 9:00 pm local daylight saving time in South Australia showing Venus in Capricornius. Similar views will be seen elsewhere at the equivalent local time (click to embiggen)

Bright white Venus is readily visible in the evening western twilight sky from around half an hour after sunset for somewhat over an hour and a half. Venus is Capricornius this week, and passes gamma Capricornii (magnitude 3.6) on the 7th, and Deneb Algedi (delta Capricornii, magnitude 2.9) on the 9th. You will have to wait until quite late in the twilight to see tehse stars appear.

Jupiter was at opposition, when it is biggest and brightest as seen from Earth, on Saturday the 29th of October.

However, Jupiter is still a great binocular and telescope object and will be for many weeks to come. Jupiter is visible for most of the night in the north-western sky, setting an hour and a half after midnight.

Evening sky on Saturday January 7 looking north as seen from Adelaide at 10:00 pm local daylight saving time in South Australia showing Jupiter and the waxing Moon. Similar views will be seen elsewhere at the equivalent local time. INSET: Jupiter and its Moons as seen telescopically at this time, (click to embiggen)

In the evening Jupiter is readily visible in the northern sky, from about twilight, and the north-western sky when it is fully dark.

Now is a good time for telescopic observation of this massive world, or follow its moons in binoculars. For good telescopic observation Jupiter is best from 9 pm - 12 am.

Although Jupiter is the most prominent now, there are lots of interesting things in the sky to view with a telescope. If you don't have a telescope, now is a good time to visit one of your local astronomical societies open nights or the local planetariums.

Southern horizon as seen from Adelaide at 3:30am ACDST on Saturday morning January 7. Similar views may be seen from other Australian locations at equivalent local time (click to embiggen).

Comet Lovejoy gave those of us not benighted by cloud some very good views over Christmas. Despite being faint, there was an astounding tail that stretched high into the night sky (an image gallery is here and here).

The comet has faded considerably now. Some keen-eyed people can still see it with averted vision under very dark sky conditions, but for most of us it will only be visible in strong binoculars or telescope. After the 9th the Moon's light will interfere significantly with seeing the comet.

Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pm AEDST. For further details and more information on what's up in the sky, see Southern Skywatch (this will be up dated to January a little later).

Cloud cover predictions can be found at SkippySky.

Lovejoy Diary Day 13

2012-01-02T21:35:00.000+10:30

From my cousins farm in western Victoria, the skies were brilliantly clear, the Milky Way twisting like smoke above my head.

Sadly, there was no sign of comet C/2011 W3 Lovejoy, someone with better eyes might pick up a faint trace, but for me comet Lovejoy is now gone from unaided eye visibillity. Tomorrow it should be in the view of the GRAS telescopes, so my telescopic campaign will begin.

Lovejoy Diary Day 12

2012-01-01T09:45:00.000+10:30

Rang in the New Year with cloud. How unusual. Hope you all had a great New Years eve, and a wonderful 2012.

Venus on New Years Eve, 2011

2011-12-31T23:15:00.000+10:30

Lovejoy Diary Day 11

2011-12-31T16:18:00.000+10:30

Slept in. Missed a call from ABC local radio about strange goings on in the sky.

Lovejoy Diary Day 10

2011-12-30T03:56:00.001+10:30

Clear skies, although somewhat moisture laden. Comet C/2011 W3 Lovejoy seen with difficulty against the Milky Way. Needed averted vision to be sure. Still moderatley visible in binoculars, visually tail probably only around 6 degrees long now.

Lovejoy Diary Day 9

2011-12-29T10:38:00.000+10:30

Cloud again. I caught a glimpse of comet C/2011 W3 Lovejoy through occasional sucker holes, and it appeared much faded, but that could be due to thin remanant cloud.

Saw two satellites flying in formation, then a third passed them the other way.

Venus and the Moon, December 28, 2011

2011-12-28T22:38:00.000+10:30

The Sky This Week - Thursday December 29 to Thursday January 5

2011-12-28T12:14:00.005+10:30

The First Quarter Moon is Sunday January 1 (New Years day). Venus is easily visible in the western evening sky. Jupiter dominates the evening sky to the north once Venus has set. Jupiter is near the waxing Moon on the 2nd and 3rd. Mars is visible in the morning sky heading towards Saturn, which is near the star Spica. Mercury at its best in the morning near the horizon. Comet Lovejoy is faintly seen in the morning sky below the Southern Cross. Earth is at Perihelion on the 5th.

Sorry no diagrams this week, due to lack of internet access while travelling and using a borrowed computer with none of my programs, Southern Skywatch will be delayed as well.

The Christmas Comet, comet C/2011 W3 Lovejoy, is fading. It is currently as bright as the Magellanic clouds, and its magnificent tail is shortening. As of writing, although dim it is still easily seen with the unaided eye as a streak of faint light below the pointers (alpha and beta Centauri) below the Southern Cross (although light polluted suburban sites may have a lot more difficulty picking it up, and need binoculars already). It will fade during the week, and may become a binocular object by the end of the week. UPDATE 31 Dec the comet has faded more quickly than I expected. It is now very difficult to see with the unaided eye except at the very darkest sites.

When looking for the comet, you will need to get up at least an hour and a half before local sunrise to see it at its best. You will need to wait a few minutes in the dark for you eyes to accommodate to the darkness to pick it out. Even things like mobile phone screens and the preview panes on digital cameras can mess up your night vision. The comet currently begins juts above the southern horizon and extends up to just below the pointers. It will rise higher in the sky as it fades, making it easier to see. Even as the comet fades it will still be a great sight.

As long as you are up looking at the comet, wait a a while for Mercury to rise.This and next week are the best times to see this fleet world in the morning.

Lovejoy Diary Day 8

2011-12-28T03:37:00.001+10:30

Not so good this morning, caught glimpses of comet in gaps in the cloud. Got the impression it had faded quite a bit, but hard to be sure with cloud reflecting light from town. Saw ISS pass in front of tail through gap in cloud.

A Short Christmas Walk

2011-12-27T16:48:00.000+10:30

The extended family went for a walk to Cape Shenk, it was wild and wooly.

Lovejoy Diary Day 7

2011-12-27T04:12:00.001+10:30

Saw the comet again this morning, got up at 3:30 am to mostly clear skies and headed up a nearby hill where I could block out the anoying marine navigation light.

There were some clouds around the southern horizon, but they soon cleared to show comet C/2011 W3 Lovejoys tail streching up past the pointers.

The tail is much dimmer now, still easily seen with the unaided eye if your sky is reasonably dark, about as bright as the large Magellanic cloud. There is no identifyable head.

For imaging I was using 800 ASA and 15 secs exposure.

Chased away from this remaarkable comet by cloud at 4:30 am.

Some Images of Comet Lovejoy

2011-12-26T22:33:00.001+10:30

Seeing as I can't post any of my images, I thought I'd post some links to other people's amazing images (much better than mine).

Colin Legg's amazing animation of the comet rising in Perth

http://vimeo.com/34007626

Image taken from the international Space Station around the same time

http://blogs.discovermagazine.com/badastronomy/2011/12/22/a-celestial-visitor-seen-from-space/

Evolution of the comet tail courtesy Rob Kaufman

http://i727.photobucket.com/albums/ww271/Rob_Kau/W321-25Dec2011ver2.jpg

Another Colin Legg's image

http://www.iceinspace.com.au/forum/attachment.php?attachmentid=105827&d=1324518566

A great image from the Possum Observatory

http://www.possumobservatory.co.nz/comet_Lovejoy-2011w3-20mm_f2,8-12800iso-28sec-2011dec26-3,11am-drummond.jpg

The Comet from Siding Spring Observatory by Rob McNaught

http://msowww.anu.edu.au/~rmn/C2011W3.htm

Guillermo Abramson with some very good images form South America.
http://guillermoabramson.blogspot.com/2011/12/ultimas-fotos-del-cometa-lovejoy.html

Lovejoy Diary Day 6

2011-12-26T10:45:00.000+10:30

Cloud again. There are heaps of fantasic images being taken by friends and from space, but with my only connection to the internet my mobile phone, I can't link to them.

Lovejoy Diary Day 5

2011-12-25T09:46:00.001+10:30

The lightning storms of last night returned with roof rattling vengance in the morning. The sky lit up like flashbulbs, and noone got any sleep from the rolling, cracking thunder.

Needless to say, I didn't do any comet watching, took photos of ligtning wracked clouds instead.

Lovejoy Diary Day 4

2011-12-24T03:55:00.001+10:30

It's 4:15 local time on upthe. Mornington Peninsula, the tail of comet C/2011 W3 Lovejoy stretches anastonishing 15 degress above the horizon. At this relative dark site it's like a pale searchlight piercing the heart of Centaurus.

A bit frudtrating as a) there is a bright navigation light I can't block out and b) I can't post any photos, I can only post via mobile phone.

Still, the comet tail is magnificent, and will be great on christmas morning.

Road Trip Night 2

2011-12-23T21:16:00.000+10:30

Venus sets over the Mornington Peninsula in the evening twilight. Click to embiggen.

Road Trip Diary Day 2.3

2011-12-23T08:31:00.000+10:30

Cockatoo post office bell in Horsham, Victoria. Note Lovejoy concealing clouds.

Lovejoy Diary Day 3

2011-12-23T08:27:00.001+10:30

Cloud, (sigh)

Road Trip Again

2011-12-22T12:24:00.001+10:30

We are off on another road trip, with limited internet connectivity, so posts and pictures of comet will be sporadic.

If I don't communicate before then, Merry Christmas and a Happy New Year, and enjoy our Christmas comet.

I Saw It Again! (comet Lovejoy's tail is pretty)

2011-12-22T12:01:00.001+10:30

Getting up at 4 am did the trick, the tail was visible by 4;30 and best around 4;45. I still used my Google SkyMap to orient myself. The tail was best seen with averted vision, but given that the tail is in the most light polluted part of the skywhere I am, rising over the cement works lit up like a chistmas tree, that is not bad.

Observing Comet C/2011 W3 Lovejoy's Tail (A Christmas Comet)

2011-12-21T12:20:00.005+10:30

Location of Comet C/2011 W3 Lovejoy at 4:30 am on Thursday 22 December (roughly an hour and a half before sunrise) as seen from Adelaide, similar views should be seen elsewhere in Australia at equivalent local times. Although close to the horizon, a 10 degree tailwill stick up past the bright star above the comets position (click to embiggen).

I saw the tail of comet C/2011 W3 Lovejoy on Wednesday morning at 4:54 am, although from others descriptions and images, its obvious that earlier is better (around 4:00 - 4:30 am) , the tail is quite long, and is readily seen in the earlier hours.

You will need a relatively clear, level horizon, preferably without too many bright lights in the way. You may need to sweep the south-eastern horizon for the tail to pick it up, but once you see the tail you should pick it up with the unaided eye. The comet is fading, but also rising higher in the sky, so the tail should be a bit more obvious over the next few days, it might even be mildly spectacular for Christmas. Certainly worth getting up at Dark O'Clock for, the best comet since C/2006 P1 McNaught.

I SAW IT! (Comet Lovejoy's Tail in the Twilight)

2011-12-21T05:55:00.004+10:30

Comet C/2011 W3 Lovejoy's tail imaged around Nautical twilight on December 21, 2011. Left Image: Comet Lovejoy's tail at 4:54 am ACST, Largs North Adelaide, 5 second exposure with a Canon IXUS 100IS, 400 ASA at 3x zoom. Right Image: Comet Lovejoy's tail at 4:57 am, 4 second exposure with a Canon IXUS 100IS, 400 ASA 3x zoom. Compare with Vello Tabur's image. Click to embiggen, the faint tail goes past epsilon Scorpii (star centre of images)

Got up at 4:30 am this morning, and the sky was magnificently clear. Struggled into my gear and headed out with binoculars and camera. Unfortunately, the comet was located not only close to the horizon, but towards the greatest concentration of sodium lights in my area and the brightly lit cement factory. With the help of Google SkyMap on my mobile phone (cringe) I located the rough area where the comet should be around 4:50 am.

Soon as I swept with binoculars I could see it, once I knew that I was actually looking at the comet tail (rather than a thin plume of smoke from the cement factory), it was identifiable (just) to the unaided eye.

Like Vello Tabur I could easily identify the tail on images taken with my digital camera (not an SLR). The tail extended past epsilon Scorpii, so was at least 5 degrees long.

The tail was easily identifiable in binoculars out to at least 5:09 am ACDST. At no stage could I see the head though (in contrast to the recent telescopic daylight images), even though faintish stars like epsilon Sco and mu 1&2 Sco were easily visible in binoculars.

So I have to get up a 4:00 am to catch the sky at it's darkest and see if I can get better images of the tail.

I also got to see the ISS shoot between Spica and Saturn and the Moon, so it was a VERY good morning.

More Amazing Comet C/2011 W3 Lovejoy Images

2011-12-20T22:38:00.005+10:30

High resolution false colour image of Comet C/2011 W3 Lovejoy from the STEREO H1A imager. Images courtesy of Karl Battams and STEREO/NASA.

Comet Lovejoy moves away from the Sun 18-19 December 2011, false colour, note the development of an ion tail. The long "spikes" from the comet and Jupiter (the other bright object) are imager artefacts. See my animation below.

Some more fantastic images of comet Lovejoy are coming out of the data. Via Karl Battams we have a quicktime movie of Comet Lovejoy in STEREO/SECCHI's EUVI-A imager's 171-Angstrom wavelength camera, showing amazing wiggles in the comets tail.

Then there is an animated H1A view of the comet, processed differently from mine to subtract stars.

Animation of the comet in H1A in false colour to highlight tail details.

Comet C/2011 W3 Lovejoy's Tail Visible

2011-12-20T22:03:00.004+10:30

Location of Comet C/2011 W3 Lovejoy at 4:54 am on Wednesday 21 December (an hour before sunrise) as seen from Adelaide, similar views should be seen elsewhere in Australia at equivalent local times. Although close to the horizon, a 5 degree tail should stick up past the bright star above the comets position (click to embiggen).

I had no luck seeing Comet C/2011 W3 Lovejoy this morning, clouds of course. But two groups did. Peter Sayers in Tasmania (Image via Space Weather) could see it as a just unaided eye object in the twilight, while Vello Tabur couldn't see it in binoculars or unaided eye, but a five degree tail turned up in his DSLR shots.

I'll have another go this morning, hopefully the weather will be kinder, and I will be forearmed with knowledge of comet Lovejoys dimness.

The Sky This Week - Thursday December 22 to Thursday December 29

2011-12-20T07:56:00.008+10:30

The New Moon is Sunday December 25 (Christmas day). Venus is easily visible in the western evening sky and close to the crescent Moon on the 27th. Jupiter dominates the evening sky to the north once Venus has set. Mars is visible in the morning sky heading towards Saturn also visible in the morning sky near the star Spica. Mercury is visible in the morning near the horizon, and is close to the Moon on the 23rd. Comet Lovejoy may be seen in the morning sky.

Morning sky looking north-east as seen from Adelaide at 5:00 am local daylight saving time on Friday December 23 showing Saturn near Spica and the waning Moon. Similar views will be seen elsewhere at the equivalent local time. Click to embiggen.

The New Moon is Sunday December 25.

Mars is in the north-eastern morning sky, in the constellation of Leo. It is heading towards Spica and Saturn.

Saturn is above the north- eastern horizon, not far from the bright star Spica.

Mercury appears low in the morning twilight. You will need a reasonably, clear eastern horizon to see it. On the 23rd, Mercury is close to the crescent Moon, forming an attractive triangle with the bright star Antares. The comet Lovejoy's location is shown (see below for more details).

Evening sky on Tuesday December 27 looking west as seen from Adelaide at 9:00 pm local daylight saving time in South Australia showing Venus in Capricornius. Similar views will be seen elsewhere at the equivalent local time (click to embiggen)

Bright white Venus is readily visible in the evening western twilight sky from around half an hour after sunset for somewhat over an hour. Venus is Capricornius this week, but does not pass any bright stars. On December 27, Venus is close to the crescent Moon.

Jupiter was at opposition, when it is biggest and brightest as seen from Earth, on Saturday the 29th of October.

However, Jupiter is still a great binocular and telescope object and will be for many weeks to come. Jupiter is visible for most of the night, setting in the early morning.

Evening sky on Saturday December 24 looking north as seen from Adelaide at 10:00 pm local daylight saving time in South Australia showing Jupiter. Similar views will be seen elsewhere at the equivalent local time. INSET: Jupiter and its Moons as seen at this time, Europa will pass in front of Jupiter from around 22:00 ACDST, Ganymede will be eclipsed and Io will also pass in front of Jupiter (click to embiggen)

In the evening Jupiter is readily visible in the north-eastern sky, from about twilight.

Now is a good time to begin telescopic observation of this massive world, or follow its moons in binoculars. For good telescopic observation Jupiter is best from 9 pm - 1 am.

There are some good Jupiter Moon events, as on the evening of December 24, you can find a list of Jupiter Moon events with timings here (scroll down a bit)..

Although Jupiter is the most prominent now, there are lots of interesting things in the sky to view with a telescope. If you don't have a telescope, now is a good time to visit one of your local astronomical societies open nights or the local planetariums.

Eastern horizon as seen from Adelaide at 4:54 am ACDST on Sunday morning December 25 (an hour before sunrise). Similar views may be seen from other Australian locations at equivalent local time (click to embiggen).

Comet Lovejoy is a newly found Kreutz sungrazing comet that surprisingly survived after a close encounter with the Sun. While people have seen comet C/2011 W2 Lovejoy in daylight with telescopes, there is no unambiguous report of seeing comet Lovejoy by the unaided eye (the horrible weather hasn't helped).

There is a possibility that we might see a tiny tail and possibly the comet above the horizon in the twilight in the coming days, it almost certainly should be visible in good binoculars. The Stellarium image above shows where the comet should be at nautical twilight. You will need a flat, clear eastern horizon for a good chance to see the comet (if it is visible). But it should be easy to find near the spine of the scorpion.

In contrast comet C/2009 P1 will be easily visible in good binoculars as a small fuzzy ball with a short tail.

Printable PDF maps of the Eastern sky at 10 pm ADST, Western sky at 10 pm ADST. For further details and more information on what's up in the sky, see Southern Skywatch.

Cloud cover predictions can be found at SkippySky.

Can We See Comet Lovejoy in the Tuesday MorningTwilight

2011-12-19T15:59:00.004+10:30

Eastern horizon as seen from Adelaide at 5:30 am ACDST on Tuesday Morning December 20. Similar views may be seen from other Australian locations at equivalent local time (cick to embiggen).

While people have seen comet C/2011 W2 Lovejoy in daylight with telescopes, there is no unambiguous report of seeing comet Lovejoy by the unaided eye (the horrible weather hasn't helped).

From the the latest STEREO images (see video below, Mercury and Jupiter are in the frame as well) and telescope reports, it seems that the comet is currently around the brightness of Mercury. Predicting what the comet will do, and how bright any tail will be, is fraught with uncertainty however.

There is a possibility that tomorrow morning (Tuesday Dec 18) we might see a tiny tail and possibly the comet above the horizon in the twilight. The Stellarium image above shows where the comet should be shortly after nautical twilight. You will need a flat, clear eastern horizon for a good chance to see the comet (if it is visible).

It's worth getting up for a look, this has been an extraordinary comet, and it's possible that we may see something beautiful (even though it is more likely we will see nothing).

Carnival of Space #228 is here.

2011-12-18T22:40:00.002+10:30

Carnival of Space #228 is now up at The Next Big Future. Comet Lovejoy features (naturally), as does the discovery of gypsum on Mars (more water), black hole lunches, the Golden Age of space exploration as seen from the 1960's and much, much more. Head on over and have a read.

Science Communicators Picnic

2011-12-18T22:36:00.000+10:30

Today the ASCSA had their end of year 'do' at Cleland Conservation Park. Despite it being rainy, the misty cloud made it sort of magic. The boys and I also toured the reptile house.

Comet C/2011 W3 Lovejoy and its Ion Tail

2011-12-18T08:23:00.005+10:30

Left Image: C/2011 W3 Lovejoy in SOHO C3 (17 December UT). Right Image: C/2011 W3 Lovejoy in STEREO beacon (low resolution) images in H1A (17 December, far right). Click to embiggen. Image credit NASA/SOHO and NASA/SECCHI. (earlier images here and here).

Images show brightness of the comet and the development of the ion tail.

The comet has been telescopically imaged in daylight a few times now, see image from Jakub Cerny here and from Jan here.

SOHO animation 17-12-11

STEREO H1A beacon image animation 17-12-11

Terry Lovejoy Images his Comet in Broad Daylight

2011-12-17T15:22:00.004+10:30

View of Eastern Horizon at 4:45 am ACDST on Christmas morning as seen from Adelaide, showing the location of comets Lovejoy and Garrad. Comet Lovejoy may remain bright enough to see in binoculars.

Terry Lovejoy, discoverer of Comet C/2011 W3 Lovejoy, has imaged his eponymous comet in broad daylight with a Celestron C8 telescope and a Canon 350D camera. See the image at IceinSpace
http://www.iceinspace.com.au/forum/showpost.php?s=31c59a570a89e0b8c315123103eff328&p=798668&postcount=38

He estimates the comet as being magnitude -1.2, that's 5 magnitudes greater than the predicted brightness at this time.

Much depends on how fast the comet fades now. It still might be bright enough to see in the predawn twilight tomorrow, but if not, hopefully it will be a binocular comet in time for Christmas.

Can We See Comet Lovejoy in the Sunday MorningTwilight

2011-12-17T10:29:00.003+10:30

Eastern horizon ass seen from Adelaide at 5:40 am ACDST on Sunday Morning December 18. Similar views may be seen from other Austrlaian locations.

After the astonishing survival and brightening of comet C/2011 W2 Lovejoy, there is a minute possibility that tomorrow morning (Sunday Dec 18) we might see a tiny tail and possibly the comet poke up above the horizon in the twilight.

The possibility is slight, but it's worth getting up for a look.

Comet Lovejoy gets its Tail Back

2011-12-17T09:25:00.004+10:30

Left Image: C/2011 W3 Lovejoy in SOHO C3 (16 December UT). Right Image: C/2011 W3 Lovejoy in STEREO beacon (low resolution) images in H1A (16 December, far right). Click to embiggen. Image credit NASA/SOHO and NASA/SECCHI. (earlier images here and here)

Comet Lovejoy is getting its tail back. If you embiggen the SOHO image you can see the old tail dissipating on the other side of the Sun. Without doing serious astrometery (for which I need the hir res versions of the STEREO images which will come later), my impression is that the comet is brighter.

I'm going to quote Karl Battams in full here because ~~I'm too lazy~~ he says it best.

1700UT: I'm going to hope he doesn't mind me doing this, and steal a quote here from highly-respected astronomer John Bortle: "I trust that most here appreciate that we are witnessing one of the most extraordinary events in cometary history."

Let that sink in a minute, because he is absolutely correct. This is not simply "news-worthy", or even "of great interest"; this is indeed competely extraordinary.

Sungrazing comets, particularly those of the Kreutz-group, have fascinated astronomers for decades, and no doubt terrified civilizations of the past, as their orbits hurled them through the solar atmosphere, resulting in a brilliant daytime illumination of these enormous 'dirty snowballs'. There is arguably no other object in the solar system that goes through such an intense experience as one of these comets. For days now we have been witness to such a beautiful object racing through the STEREO, SOHO and now SDO and PROBA images, blasting through the solar corona, and miraculously re-emerging, albeit with much less of a tail than it started with. And whereas sungrazers of the past have been lost at least temporarily, if not permanently, in the Sun's glare, thanks to an amazing fleet of sun-watching spacecraft we have now been enthralled by this entire passage without a single hour passing by unwitnessed. Purely for the spectacle of the event, and the way it has unfolded before our eyes over the internet, this comet has sealed its place in the history books.

But there is so much more to this than just the spectacle. We have already obtained unprecedented scientific data from five different spacecraft, and I'm very optimistic that over the coming days we will get to add a sixth spacecraft to that list when Hinode analyze their data. The result is an almost overwhelming catalog of visual, narrow-band filtered, extreme ultraviolet, and spectroscopic data of a comet experiencing the most extreme environment the solar system has to offer. We will likely learn about its mass, its physical size, its composition, the size of its dust and dust production rates, and so much more. Objects like this can also provide us with a tremendous amount of information about the solar wind and conditions in the solar corona, which in turn allows us to gain more understanding of the Sun as a driver of "Space Weather" at Earth (it's one of the reasons my group is interested in sungrazing comets).

So I could not agree more with John, and I hope that all of you who are watching these movies are indeed appreciative of just how incredible this has been!

Now head over to Karl's site and see the latest amazing imagery.

IT LIVES PART 2!!!!!!

2011-12-17T00:16:00.004+10:30

Comet C/2011 W3 Lovejoy as it returns from its encounter with the Sun as seen in the STEREO C2 Behind imager (low resolution beacon images). (Comet Lovejoy bright dot just above the bright streak of comet tail bottom left, not the other bright dot top right). COMET LOVEJOY IS COMING BACK WHILE THE TAIL IS STILL GOING IN!!!!

Astonishing. You get a better idea of what is going on in the animation below.

Previous posts on the return linked here.

IT LIVES!!!!!!

2011-12-16T22:22:00.005+10:30

Comet C/2011 W3 Lovejoy on its way back out from it's encounter with the Sun.

Left Image: C/2011 W3 Lovejoy in SOHO C3 (16 December UT), astonishingly, it has left its tail behind (the comet the is bright object to the right of the occulting disk). Right Image: C/2011 W3 Lovejoy in STEREO beacon (low resolution) images in COR2A (16 December), the disconnected tail can't be seen in this image. Click to embiggen, scroll down for animations. Image credit NASA/SOHO and NASA/SECCHI.

Well, that was amazing! Not only did comet Lovejoy survive its passage over the Sun (captured here is this astonishing SDO animation), but it is still bright, although it has left most of its tail behind. According to Karl Battams, it is the brightest Kreutz comet SOHO has ever seen. And apparently an ion tail has never been seen on a Kreutz comet before.

There is intense discussion on the Comets ML list. Is comet Lovejoy bigger than we thought, are we seeing vaporizing iron? This comet, as well as being spectacular, will certainly add to our current meagre knowledge of Kreutz comets.

Congratulations Terry on an amazing discovery, and once again congratulations to the STEREO, SOHO and SDO teams for capturing this amazing comet.

What a ride! Earlier images and animations, Solar exit, Solar contact, 16 Dec approach, 15 Dec, 13 Dec, 12 Dec.

Animation showing the comet going behind the occulting disk then coming out without its tail.

Lovejoy heads towards the STEREO Ahead C2 occulting disk and comes out the other side sans tail. Low resolution beacon data, drop out of data in the middle so you miss the comet going behind the occulting disk.

Comet Lovejoy Exits the Sun

2011-12-16T15:06:00.004+10:30

Comet C/2011 W3 Lovejoy goes behind the COR1 occulting disk in the COR1 low resolution beacon images from the STEREO behind spacecraft.

Comet Lovejoy exits the sun in these SDO images (video)
http://t.co/I4TiZ1xq See also here and here for amazing videos.

But the comet has not re-emerged in the COR1 images yet, looking at the SDO images, it might just be an organized debris cloud that will evaporate by the time the it passes into the COR1 field of view.

Video showing comet Lovejoy entering the STEREO COR1B imager and not coming out (yet). Low resolution Beacon images.

Congratulations to the STEREO and SDO team for some fantastic images and science! See Karl Battams page here for updates.

Comet Lovejoy Skims the Sun

2011-12-16T11:06:00.003+10:30

Comet C/2011 W3 Lovejoy in the STEREO COR2 Behind imager, as the comet disappears behind the occulting disk.

Couldn't see it by eye, too much glare around Sun from thing cloud.

Scroll down for animation of it as it skims above the Sun in the SDO imager.

Animation of comet Lovejoy as it skims near the Sun in the SDO imager (image Credit, NASA/SDO). Look carefully at centre as comet blinks in and out.

Link to larger SDO animation.

Comet Lovejoy Plunges Towards the Sun (part 2)

2011-12-16T08:15:00.003+10:30

Left Image: C/2011 W3 Lovejoy in SOHO C3 (15 December UT). Right Image: C/2011 W3 Lovejoy in STEREO beacon (low resolution) images in COR1B (15 December). Click to embiggen. Image credit NASA/SOHO and NASA/SECCHI. the SOHO image shows an ion tail you will eed to embiggen to see.

Comet C/2011 W3 Lovejoy continues to plunge towards the Sun. Around 2.5hours from perihelion, it is still bright (magnitude -6 maybe), and as yet undisintegrated. See Karl Battams site for mre images and details.

Earlier images and animations, 15 Dec 13 Dec, 12 Dec.

Comet Lovejoy Plunges Towards the Sun

2011-12-15T22:44:00.007+10:30

Left Image: C/2011 W3 Lovejoy in SOHO C3 (15 December). Right Image: C/2011 W3 Lovejoy in STEREO beacon (low resolution) images in COR1B (15 December). Click to embiggen. Image credit NASA/SOHO and NASA/SECCHI.

Comet C/2011 W3 Lovejoy continues to plunge towards the Sun. Around 12 hours from perihelion, it is still bright (Karl Battams estimates around magnitude -2), and as yet undisintegrated.

Earlier images and animations, 13 Dec, 12 Dec.

Comet Lovejoy enters the COR1 ahead instrument, low resolution beacon images.

Comet C/2011 W3 Lovejoy Brightens!

2011-12-15T16:21:00.006+10:30

Left Image: C/2011 W3 Lovejoy in STEREO H1A (12-13 December) in false colour, showing the tail being twisted by the solar wind (better seen in the animation below). Right Image: C/2011 W3 Lovejoy in STEREO H1B (13 December) showing partial tail disconect (again, better seen in the animation below). The bright vertical line line is an imaging artefact. STEREO raw data courtesy of Karl Battams.

Karl has more information and animations (including the son of lovejoy), here. For previous images, animations and orbit descriptions see this post. Rob McNaught suspects it may not get above magnitude -6 (brighter than Venus but hard to see in daylight). It looks like it may survive to at least perihelion (but then, it will probably spectacularly disintegrate now).

Left Image: C/2011 W3 Lovejoy in SOHO C3 (14-15 December) (better seen in the animation below). Right Image: C/2011 W3 Lovejoy in STEREO H1B beacon images (14-15 December). The bright vertical line line is an imaging artefact. Image credits NASA/SOHO and SECCHI STEREO.

Comet C/2011 W3 Lovejoy as seen in STEREO H1 Behind 13 December 2011, tail disconnection seen . Raw data courtesy Karl Battams

Comet C/2011 W3 Lovejoy as seen in STEREO H1 Ahead spacecraft 12-13 December 2011, tail movement in solar wind seen. False colour image. Raw data courtesy Karl Battams

Comet C/2011 W3 Lovejoy as seen in SOHO spacecraft C3 imager 14-15 December 2011. Raw data courtesy NASA/SOHO

Comet C/2011 W3 (Lovejoy) in STEREO

2011-12-14T13:17:00.008+10:30

Comet C/2011 W3 Lovejoy (also known as the great "Birthday" comet of 2011) on the 12th of December as seen from the STEREO Behind spacecraft. Video is below (scroll down).

Comet Lovejoy is now so bright you can easily see it in the low resolution STEREO beacon images (see here to search the beacon images for the latest pictures, and see below for an example image). It has also entered the LASCO C3 imager field of view, this animation (10 mb) shows it entering as a bright streak to the bottom of the image.

Comet C/2011 W3 Lovejoy, discovered by Australian amateur Terry Lovejoy, is the first Kreutz comet found from Earth since 1970. It was found with a modest 8" telescope too! Terry's account of his discovery is here. Here's an image from Rob Kaufmann and one from Michael Mattiazzo shortly after discovery.

Comet Lovejoy is the bright diagonal streak bottom left) on 14 December in the low res STEREO H1B beacon images

Terry is now the first person to discover a Sungrazing comet from both ground and space-based telescopes.

The big question on everyone's minds is "how bright will it get, and will it survive?" Kretuz comets have a tendency to evaporate as the approach, or pass close to the sun. Comet Al has a nice series of images showing this evaporation.

There's lots of discussion on the Comets ML list about this issue, the comet is probably 200 meters across, and there is an odds on chance it will just break up.

How bright will it get?

Again, there are lots of unknowns, a current magnitude plot is here, and should Comet Lovejoy survive it's journey inward, it might just get bright enough to see in the daylight. Might, as you can see from the images above (SkyMap image to the left, Stellarium image to the right, click to embiggen) the comet comes pretty close to the Sun, so it may not be possible to see it, even if the comet gets as bright as Venus.

The comet is probably (given all the unknowns and the very good possibility that it will disintegrate well before reaching the Sun) be reaching it's brightest at 11 am ACDST (around 11:30 AEDST) on the 16th of December in Australia. Do NOT attempt to locate the comet near the Sun unless you are an experienced solar observer, and have a decent solid building to block out the Sun.

Karl Battrams has a comprehensive page on the comet with nice GIF animations here.

Animation of comet Lovejoy from STEREO H1 Behind images on 12 December provided by Karl Battrams.

Geminid Meteor Shower December 14-15, 2011

2011-12-14T06:56:00.002+10:30

The radiant of the Geminid meteor shower above the northern horizon as seen from Adelaide on the morning of December 15 at 3:00 pm ACDST, similar views will be seen from other sites at equivalent local times.

The Geminid Meteor shower is at its peak from the point of view of Australian's on the mornings of Wednesday 14 December (13 December UT) and Thursday 15 December. The best time to observe is between 1 and 4 am (daylight saving time, 12-3 am non-daylight saving time), with the highest rates between 2-3 am daylight saving time.

The Moon will unfortunately be just above the Geminid radiant, so only low meteor rates will be seen. In Australia we should see roughly a meteor every 6 minutes.

You can check predictions for you local site with the NASA meteor flux estimator (scroll down to 4 Geminids in the SHOWER box, make sure you have your location and date correct as well)..

Printable PDF maps of the Eastern sky at 10 pm ADST, Western sky at 10 pm ADST. For further details and more information on what's up in the sky, see Southern Skywatch.

Cloud cover predictions can be found at SkippySky.