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Just a couple of quick bits of news, because it's late, and because the 'a' on my keyboard is playing up which makes typing a lot like hard work:
The Dwarfs aren't out there:
NASA has released results [1] from the infra-red WISE [2] space telescope, and they have a surprise: Theories predict that there should be one Brown Dwarf [3] - an object partway between a Jupiter like planet and a small star - for every regular star. But there aren't! The number is more like one for every six regular stars.
Image above: Our local bit of the Milky way, with the positions of newly found brown dwarfs circled in red. basically, there should be more of them. The image is a view from about 30 light years away. Presumably a simulated view. If it's an actual view then my mission to keep you up do date with space related news has suffered something of a ......hiccup.
Image courtesy of NASA/JPL
Brown dwarfs are thought to form by the same process as regular stars [4] - the collapse of a huge, sparse cloud of gas. That there are fewer in our local neighbourhood may be telling us something about the history of our corner of the Galaxy, or pointing to a gap in our theories of star formation.
But WISE is still looking, and there may be further surprises. Brown dwarfs are hard to spot: They're too small to sustain hydrogen fusion [5]. Instead they briefly fuse deuterium [6], and then slowly fade and cool- in fact the coldest one found by WISE is only 25 degrees Celsius at it's surface, a record breaking cold 'star'.
Son of the Falcon to visit black rock:
JAXA [7] is looking to visit asteroid 1999 JU3 [8].... and their ship is already under construction.
Image Above: The asteroid 1999 JU3. Um. Ok, you've got me, that asteroid's Itokawa, the target of Hayabusa 1. But it's still a spectacular chunk of space rock! Go on give it chance...... fine, it looks like a 500 meter long potato. Or worse. But 1999 JU3 itself is pitch black, due to its high carbon content - the 'lead' in a pencil is actually made of carbon -which makes it very difficult to image from Earth. But while most asteroids look like huge potatoes, they make up for it by holding clues to how planet Earth, and life here, started. Image courtesy of JAXA.
Their Hyabusa 2 space ship is, according to the Japanese Asahi Shimbun newspaper, already under construction. It's based on the ion drive [10] propelled Hayabusa (which means 'peregrin falcon') probe, that had a 'very eventful' mission to the asteroid Itokawa.
Which is science speak for: Things went wrong. A lot of things.
But to be fair, it was a totally new design of spaceship. The JAXA engineers are inventive, determined, and they bought the little bird home with its cargo of asteroid samples. The probe - aside from the sample return capsule, which landed safely - was then incinerated in Earths atmosphere which was a pity, but always part of the plan.
Although the probe itself might have objected to that plan
The story of triumph over adversity [11] has gone down well in Japan, probably as it shows just how much engineering talent and tenacity JAXA have. So JAXA are doing a sequel, although in cash strapped times they've had to fight for the money
Video above: Hayabusa slams into Earths upper atmosphere at very, very, high speed. The shower of huge sparks is the main probe breaking up, the little spark on the lower right is the sample return capsule, which made it back to Earth with it's cargo of asteroid bits intact. Video courtesy of NASA.
The new probe is intended to visit asteroid 1999 JU3 in mid 2018, and stay in orbit for a year and a half, It will spend it's time studying the asteroid, collecting samples for return to Earth, and possibly deploying a small lander. 1999 JU3 is getting this attention because it holds carbon chemistry, and shows signs of being altered by liquid water [12], presumably while part of a larger body like a protoplanet. Ground based observations also suggest that there may be two types of material on its surface, so perhaps we have a rubble pile of two asteroids, smooshed into one by a collision.
After all the things we've found in carbon rich meteorites [13] that relate to the origins of life - nucleobases, nucleobase analogues, amino acids - this kilometre long piece of black rock could provide us with some important clues as to how we all came to be.
List of links:
[1]http://www.jpl.nasa.gov/news/news.cfm?release=2012-164&cid=release_2012-164&msource=12164
[2]http://www.nasa.gov/mission_pages/WISE/main/index.html
[3]http://astro.berkeley.edu/~basri/bdwarfs/SciAm-book.pdf
[4]http://www.cfa.harvard.edu/news/2008/pr200824.html
[5]http://www.astrophysicsspectator.com/topics/stars/FusionHydrogen.html
[6]http://www.astrophysicsspectator.com/topics/degeneracy/BrownDwarfStructure.html
[7]http://www.jaxa.jp/index_e.html [8]http://en.wikipedia.org/wiki/(162173)_1999_JU3
[10]http://www.jaxa.jp/article/special/hayabusa/kuninaka_e.html
[11]http://www.bbc.co.uk/news/10285973
[12]http://iopscience.iop.org/1538-3881/135/4/1101/
[13]http://www.pnas.org/content/early/2011/08/10/1106493108
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