Thursday, August 31, 2006
Supernova in Real Time
Back in February, NASA's Swift Gamma ray telescope caught a curious burst of energy. Today, no less than four papers appeared in the journal Nature explaining the meaning of that energy burst.
It looks as if we have caught a supernova explosion in real time. Gamma ray bursts have long been frustrating. Trying to associate these transient bursts with astronomical objects or events has been difficult, because of the short nature of the bursts. This time, the Swift telescope cauge this unusually long burst in time for a batter of telescopes to observe the area, and for the first time were able to follow a supernova from the very early stages in a great range of wavelengths. The best studied supernova to date , SN 1987A, lacks obervations in the early stages of the event. It appears that the gamma ray burst was unleashed from the core of a massive Wolf–Rayet star as it began to collapse on its way to Supernovahood. Intrestingly though, this star was less massive than those typically thought to be capable of producing gamma ray bursts.
Unfortunately, to read the articles and commentary you need a subscription to Nature, but you can listen to the podcast, which discusses the gamma ray bursts (as well as other things), for free.
Fred Watson wins a Eureka Prize
Southern Skywatch Up
Wednesday, August 30, 2006
Now you can watch SMART-1 smash into the Moon.
The SMART-1 spacecraft has been quietly mapping the Moon in exquisit detail while at lot of attention has been focused on Mars. The mission got extended, but now SMART-1 is out of fuel and is spiraling down for an impact on the Moon.
And we might get to see it (the impact that is, well, those of us with telescopes). On September 3 0541 UT (that's 15:41 AEST, so us Aussies won't get to see it, see here for impact visibility) SMART-1 will impact the Lake Of Excellence. The impact will be on the dark side of the Moon, and there should be a brief flash of light (like the Lunar Meteor impacts seen in previous years). Instructions for training your telescope on the Moon can be found at this ESA site, or at this Lunar Impact Monitoring Site. Video briefings about the impact can be found here.
A New Meteor Shower in Pavo?
John Drummond has reported that there may be a new meteor shower in Pavo, from Comet Levy (P/1991 L3), possibly visible over the next few days. The peak of the shower will be on August 31 and September 1, and the radiant is situated roughly between alpha and beta Pavonis (see the map on the right). A full sky map with the radiant shown is here.
How many meteors can you expect to see? Possibly none, maybe one or two per hour, maybe more. It's best to view after 11 pm, when the Moon will interfere less and the radiant is still high.
Tuesday, August 29, 2006
Shadow Transit (sort of)
Well, my astrophotography jinx stayed away for one night. The sky, which was cloudy for most of the day, cleared up in time for me to take some shots of the Moon near Spica. Unfortunately, the event occurred just on top of our family dinner, so I had to rush around a bit putting out the dinner things and taking the odd shot.
I couldn't do any telescope imaging until dinner was over. So Spica was past its closest approach and wouldn't fit into the frame in one shot, some assembly was required. Anyway, it think they came out reasonably well under the circumstances. I also got some shots of a shadow transit of Jupiter. I'll process them later.
Spica above the Moon, mosaic of 3 images (not guaranteed to be perfectly aligned. Click to enlarge the image.
Monday, August 28, 2006
Occultataion of Spica tonight (Monday 28th)
I've been a bit preoccupied with Pluto, so I nearly forgot the occultation of Spica. Tonight, people in Tasmania and Southern New Zealand will see the crescent Moon glide in front of the bright Star Spica. Tasmanians will see it disappear at 18:59 AEST, New Zealanders around 21:03 see Southern Skywatch for more details. The rest of us will see Spica spectacularly close to the crescent Moon, in Adelaide the Moon will be a mere 6 minutes of arc away (it will look like it is almost touching) at 18:15 ACST. In Melbourne it will be 4 minutes of arc at 18:57 AEST. So go and have a look between 6:00 pm and 7:00 pm and watch Spica glide past the horns of the Moon.
Sunday, August 27, 2006
The Pain of Pluto's Passed On Planethood.
For people that are confused about the change, Stuart has a good explanation of what happened and why. Cosmos magazine has an online editorial about why Pluto had to go. The Planetary Society has some good Pluto resources on their front page, and a great list of the top 10 reasons why Pluto is/isn't a planet. Over at The Pain-When will it end, is a great cartoon on Pluto's demotion.
Meanwhile, over at Cosmic Variance, Sean reminds us that some rather momentous things have happened in astronomy this week, so we should put Pluto's demotion into perspective.
UPDATE: Wow! Has Pluto ever hit the worlds conciousness. Over at Jimmy and the Keyz, you can download the catchy song "They Demoted Pluto"(with the chorus "I hate the IAU"). You can buy "Honk if you think Pluto is a Planet" bumper stickers and other Pluto related Mercandise. However, Davep sees the bright side, his equipment can see all the planets in the solar system now. (Hat tips to Bad Astronomy blog and Dynamics of Cats)
Saturday, August 26, 2006
Morning Saturn and Venus
This Sunday morning, Saturn and Venus will be so close as to almost seem to be touching. Unforntunately they are very close to the horizon, so you will need a flat horizon free of obstructions to see them clearly. Nonetheless this is a pretty rare close approach for the two, so do make an effort to see it.
Friday, August 25, 2006
Pluto is dead, so lets have a competition!
We need a planet name menomic to replace "My Very Easy memory Jingle Seems Useful Naming Planets". I've proposed "My Very Easy Memory Jingle Seems UB313-less Now" [evil grin].
So, what I want you to do is send in your menomic for planet naming. The best menomic, as judged by Oldest One and Middle One (ably helped by the Bettdeckererschnappender Weisle), will win a free copy of the September/October Sky&Space Magazine (For Northern Hemispherians, there's lots of good articles in this, so don't be put off by it being south-centric). Entries close next Friday 1 Sept. Put your entries as comments to this post (and don't include addresses or email addresses, I'll contact you later for postal details via the comments)
Pluto is not a planet anymore
The blogosphere is all aflury with the news. Stuart has a good report hot from the IAU. Both the Bad Astronomer and Tom ruminate on the meaning of all this.
On Jodcast (nimbly edited by Stuart) you can listen to an edited version of the deliberations (and there are also heaps of good IAU links). The video of the full deliberations is here.
Blast, I was looking forward to 12 planets. My Very Easy Memory Jingle Seems Useful Naming .... seems a bit silly now. Maybe it should be My Very Easy Memory Jingle Seems UB-less Now.
There is more at the IAU meeting than just Pluto, pop over to Thomas Marquarts IAU Blog
Thursday, August 24, 2006
Mars and the Crescent Moon
Mars has been difficult to pick up for some time, but this Friday the thin Crescent moon will be just below Mars. While not spectacular, it will be a rather attractive sight in the early evening.
They are probably voting about Pluto as you read this
Where's Mercury Now?
Mercury has now disappeared from our skies and is heading for Superior Conjunction in September, then it will reappear in the evening sky in late September. In the meantime, here is Mercury caught in the LASCO C3 camera (the bright object on the far right of the image).
Sunspot action is also happening again. Sunspot group 905 has roated onto the face of the Sun, it will be interesting to watch it develop over the next few days.
Important Dark Matter News
I would have thought the debate over wether dark matter exists to be long over, afte all, simple mass calculation and gravitational lensing shows that galaxies contain more mass than can be accounted for by shiny stuff like stars. The controversy is over what the dark stuff is. Some of it is non-glowing gas and planets (and possibly neutrinos), but most people think the majority is some unusual form of matter.
Some stunning work from the Chandra X-ray telescope has thrown new light on Dark matter by mapping its distribution in colliding galaxies. The Chandra press release is here, and an ABC science article is here. For the best description of what it all means though, run, don't walk to Sean Carrolls' article at Cosmic Variance. The foolow that up with Mark Chu-Carrols' article at Good Math Bad Math.
Tuesday, August 22, 2006
The Futures so Bright, I Gotta wear Shades
Everyones seen this picture of the Earth from Space. Well here is a site devoted to mapping light pollution from space. As well as images of various parts of the Earth glowing gently, there are maps of limiting star magnitudes, and the rate of increase of light pollution. Scary Stuff, I get frustsrtaed by the skies at my suburban home in Adelaide, but we are dark compared to most of Europe. Time to join the Dark Skies Assotiation. Here is some Dark Sky resources from Adelaide to get you going.
Monday, August 21, 2006
A Spaceport for Woomera
Ah well, one can but dream.
Sunday, August 20, 2006
Open Day and Balloon Molecules
Friday, August 18, 2006
Final Bits of Science Week
Even Bigger Bangs
Wednesday, August 16, 2006
Stealth Creationism Fails Again.
Intelligent Design creationists have apparently been beavering away in the background here in Australia. The new Federal Education and Science Minister Julie Bishop has just said it (ID) should not be taught in schools.
"I have had submissions in relation to this matter and as the minister for science I can state that it's my view that it is not part of a science curriculum," Ms Bishop said.
I thought this was all done and dusted when the previous minister Dr. Brendan Nelson, after appearing to support ID, said that it shouldn't be taught in schools. Perhaps the ID creationists thought the regime change was a chance to have another go.
My mate John Wilkinns has his own perspective here.
Planetary Proposal Preserves Pluto
(1) A planet is a celestial body that (a) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape1, and (b) is in orbit around a star, and is neither a star nor a satellite of a planet.2This keeps Pluto as a planet, and UB313 becomes a planet... as does the asteroid Ceres, surprisingly. This definition is different from the one Stuart has discussed.
Has the New Solar Cycle Started?
Sunspot group 904 is pretty big now, and being almost face on easily visible using safe solar projection techniques, or with the unaided eye. Top of the Lawn shares his sunspot experience with us.
All is relatively quite in the solar storm are though, so no aurora are expected from this group. However, back on July 31, there was a small, inconspicuous sunspot. This sunspot was unusual in that it had the reverse magnitic polarity to what you would have expected. We are currently at solar minimum, and a new sunspot will begin when the sunspots reverse polarity. The new sunspot cycle, cycle 24, is ecxpected to be particularly strong.
However, the reverse poarity sunspot didn't last very long, so we may not be in a new cycle yet. See Science@NASA for the full story.
Tuesday, August 15, 2006
Somewhere in July the number of extrasolar planets passed 200. Despite the number of them, I still get excited over them, a new "low" mass planet (7.5 times Earth mass the lowest mass ever found so far), has just been described in a three planet system!
But new results from the Spitzer Space telescope potentially blows that total away. The image to the left of Orion and the region near it looks a bit like a hockey stick. The are that looks like the shaft stretches 70 light-years beyond the Orion nebula. This area contains 800 stars about the same mass as our sun. These sun-like stars don't hang out in big clusters of stars like the one in the Orion nebula; instead, they are be found in small clusters (right box inset), or in by themselves (middle box inset).
Stunningly, the infrared Spitzer Space telescope found 2,300 planet-forming dust disks around young stars in the Orion cloud complex. While these dust disk may not have formed planets yet (although there may be protoplanets in them), the very thought that there are potentially 2,300 planetary systems just a stones throw away (cosmically speaking) is truly mind-boggling.
Stuart's Astronomy blog's 500th, and IAU blogging
Sunday, August 13, 2006
Science Week has Started!
Comets P/2006 HR30 (Siding Spring) and P1 (Mc-Naught)
Comets P/2006 HR30 (Siding Spring) and P1 (Mc-Naught) and around magnitude 15 or so at the moment, and only really visible to popel with serious kit. However, there are some nice images of HR30 (found by Australia's Siding SPring Observatory) here and here and a nice animation here.
P1 Mc-Naught (discovered by an Australian astronomer, Rob McNaught) is currently in Scorpio, but during January 2007 it will swing past the Sun, possibly becoming brighter than magnitude 2. While this wil be unobservable to us (too close to the Sun), it will possibly be caught on the SOHO C3 camera. P1 will also probably be a reasonably bright but difficult binocular object in the Southern Hemisphere in late January early February. Images of P1 McNaught are here.
Meteorite Fragments Recovered in Norway
Update on Sunspt Group 904
Sunspot group 904 is growing, and is now big enough to see with safe solar projection techniques. It is even visible to the unaided eye (as a dot) when safely behind eclipse-grade solar film (never look at the sun directly). WHile tempted to drag out the reflecter and web-cam, I was seduced by gardening and playing basketball with the kids instead. Although of substantial size, we are unlikley to get much geomagnetic action from this group. Here is a stunning image of this group.
Saturday, August 12, 2006
Sunspot group 904 has just rotated onto the face of the Sun. I'll keep an eye on these, as they have the potential to become big and interesting.
Thursday, August 10, 2006
It's not how I would teach Astronomy.
Wednesday, August 09, 2006
Venus and Mercury close the next few mornings
Over the next few morning Venus and Mercury will be a mere 2 degrees (about 2 fingerwidths) appart in the morning sky. The best time to see these beauties is between 6:10 and 6:35, when the sky is reasonably dark (o5 5:30 and 6:00 if you live in Brisbane), but unfortunately the pair are close to the horizon. Venus can bee seen quite a bit later, but Mercury will fade from view rapidly after 6:30.
Tuesday, August 08, 2006
Saturn in Conjunction
Saturn was at opposition at 10:00 pm on Thursday the 7th, here seen above the Sun in a SOHO image. A nice animation of Saturn approaching the Sun is here (0.8 Mb MPEG) or here (0.2 Mb MPEG)
What the fuss was about last night
Monday, August 07, 2006
Aurora alert (8:00 pm ACST)
Currently (8:00 pm ACST) we are in a stream of particles from a coronal hole. The magnetic field is strongly southwards, speed and density is high. There is currently a geomagnetic alert. the Kp index in Hobart is currently 6.0
There is a good possibility that people in Southern New Zealand and Tasmania might see auroral activity tonight (tasmanians should look now), although light from the waxing Moon will interfere, and dark sky sites have the best chances of seeing anything.
People in Southern Victoria might have a possibility of seeing some display.
Sunday, August 06, 2006
The Mars Hoax that Wouldn't Die
Where's Saturn Now?
This image snapped by SOHO shows Saturn (bright object centre left) near the Sun. Saturn is in conjunction with the Sun on Monday the 7th. See this animation (8Mb) for Saturn approaching the Sun (Saturn only turns up near the end)
Thursday, August 03, 2006
Comet 177P Barnard
Wednesday, August 02, 2006
Occultation of Antares 4-5 August
In Cape Town, Antares will disappear behind the dark side of the Moon at 6:22 pm (4th) local time, and reappear from the bright side at 7:29 pm.
In Perth, Antares will disappear behind the dark side of the Moon at 2:33 am (5th) local time, and the Moon sets before Antares reappears.
Science Week and Open Telescope Night in Adelaide
Of course, there is too much to fit into two weeks, so there are many "pre-events". If you are in Adelaide, there is an open observatory night at The Heights High School, Modbury Heights, this Friday at 8:00 pm. Costs $4 for adults, $1 for kids. Full details via the link above.
Of course I won't be going, Eldest one and I got given free tickets to the Soccer on that night, so we are already committed. Like tonight, it was a playoff between a free talk on Global Warming by Adelaides Thinker in residence Stephen Schneider and Comedienne Rachel Berger, and a talk by Noble Laureate J. Robin Warren speak on his work on bacteria and ulcers. In the end we stayed home and held a birthday party for Middle One's toy dog. I drew a spaceship card for him.
Tuesday, August 01, 2006
Where's Jupiter on Wednesday?
It will also be a good night to check the Movement of the Moon. Every night the Moon covers about two handspans distance across the sky, that's roughly a fingerwith every two hours, something that is easily observable.. if you have a landmark to tell the position of the Moon. Well, you can use Jupiter as your landamark, check the position of the Moon against Jupiter every hour, and you can watch the Moon move across the sky.
If you want to see more great pictures of the Great Red SPot and Red Spt Jr, head over to the Bad Astronomer.