Thursday, February 18, 2010

WISE: First Spectacular Images Released

 

WISE launched in December and has been toiling away since. This is probably my favourite image, as it's a view of M31 Andromeda Galaxy that we haven't seen before. It looks like something a science fiction illustrator would come up with, but in reality it's a false colour infrared picture of this well known galaxy. I like this so much in fact, it's become my desktop wallpaper!

Some great interpretation of WISE's newest images, as usual, from the Bad Astronomer Phil Plait:http://tinyurl.com/ylluozz

WISE mission home page: http://wise.ssl.berkeley.edu/

 

Posted via web from John's posterous

Tuesday, February 16, 2010

Light Shed on Mysterious Supernova and the Star Behind It

A supernova that lasted an unprecedented 555 days, SN2007bi, appears to have been caused by a star that technically should not exist....today. The monster that led to this supernova ought to have been more than 300 solar masses, but this seems to contradict current theories, backed by observational data. A protostellar cloud would gravitationally collapse to form a star at 150 solar masses or less, and would never get even close to 300 solar masses. Stars this large just can't form.

However, that's in todays universe.

Back in the early days, when the universe was less than a few hundred million years old, the universe consisted only of hydrogen, helium and a little lithium which were forged in the first three furious minutes following the Big Bang. Heavier elements had not yet been formed as the universe cooled too quickly after the Big Bang to continue building elements, and the stars that would eventually synthesise them didn't yet exist. Huge amounts of these light elements had to come together before reaching the critical mass necessary for gravitational collapse that leads to stellar ignition, hence the truly enormous mass of these early stars. These first stars burned quickly (quickly for stars, ie a few million years) and brightly before exhausting their reserves of hydrogen and exploding in supernovae, creating heavier elements and sending them out into the universe, in the process reducing and eventually killing off any possibility of these types of stars from forming in the future. But why did it it burn so long? A hypothetical "pair-instability"-type supernova occurrs in stars this big. Hypothetical because it wasn't believed that stars this big could exist.

So how could stars this big exist today?

This supernova was seen in a dwarf galaxy 1.6 billion light years away, too nearby to be from the early universe. From observations, these dwarf galaxies seem to have significantly less of the heavier-than-lithium elements than they should have for their size. The implication here is that these dwarf galaxies may in fact be leftover "islands" of the early universe! The low mass could explain why they never accumulated to form fully sized galaxies.

This is why I love cosmology. The timescales, the distances and the concepts are so awesome, the processes so ferociously elegant....it's humbling to think that a complex glob of carbon compounds on a rock orbiting a yellow star in an insignificant galaxy can even exist to contemplate such things.

For lots more on this amazing story: http://www.newscientist.com/article/mg20527470.900-primordial-giant-the-star-that-time-forgot.html?full=true

 

Posted via web from John's posterous

Thursday, February 11, 2010

Solar Dynamics Observatory Launches !

The Solar Dynamics Observatory launched today from Cape Canaveral Air Force Station. It will study the sun's activity in order to predict, amongst other things, solar storms that can potentially knock out terrestrial power grids. Solar flares, Coronal Mass Ejections and sunspots will lose some of their mystery as we learn a lot more about the sun over the next few years from this mission.

If you've read any of my earlier posts, you'll recognise this phrase: I love it that we can do this stuff; it's soo freakin' cool!! And with Twitter, you can ask knowledgeable people about this stuff as it happens. The 21st century so rocks!

Posted via email from John's posterous

Wednesday, February 10, 2010

SDO launches from

The Solar Dynamics Observatory launched today from Cape Canaveral Air Force Station. It will study the sun's activity in order to predict, amongst other things, solar storms that can potentially knock out terrestrial power grids. We'll learn a lot about the sun over the next few years from this mission. Solar flares, Coronal Mass Ejections and sunspots will lose some of their mystery!

If you've read any of my earlier posts, you'll recognise this phrase: I love it that we can do this stuff, it's soo freakin' cool!! And with Twitter, you can ask knowledgeable people about this stuff as it happens. The 21st century so rocks!

Posted via email from John's posterous

Monday, February 8, 2010

Space Shuttle Endeavour STS-130 launches from KSC!

The Space Shuttle Endeavour launched from KSC this morning to deliver critical components to the ISS. It's a beautiful thing to watch.

 

Posted via web from John's posterous

Sunday, February 7, 2010

Solar Dynamics Observatory Launching Tuesday

As reported by the BA, some really cool info here, check it out!

http://tinyurl.com/yfgohvy

Posted via web from John's posterous

My baby daughter chuckling madly!