Just over 3 hours from the time I write this, the European Space Agency will launch two satellites. Both will study the early stages of the universe. Watch itlive at this link, or follow them on Twitter.
What will they do?
- Herschel will carry an infrared telescope. That means it won’t capture visual-spectrum images like Hubble has. What it will catch, in frequencies and detail never before achieved, is information about early star and planet formation. Because its sensitivity is so high, and because radiated heat is infrared, the satellite has an elaborate cryogenic system to keep it super-cool.
- Planck won’t take visual images either: it’ll measure, in great detail, the Cosmic Microwave Background radiation (that is, the radiation left over from just after the Big Bang).
Each will do lots of other things, too. Read the links.
“Lyman-alpha blobs” is just a cool way of saying “massive, distant, early-universe collections of hydrogen gas”. There have been several of them seen. Since they’re billions of light-years away, and therefore billions of years old, they tell us a lot about how the galaxies we know today evolved.
A new Lyman-alpha blob has been found, though: Himiko. It’s very far away, 12.9 billion light-years. And it’s big. Very big. Much (like, 10 times) bigger than similar blobs are, and than our models say are likely to exist.
It’ll be interesting to find out why it’s so huge. Is there a supermassive block hole at its centre? Are our models of galaxy formation wrong? Is it just a big ol’ freaky space blob?
Stay tuned. I, for one, welcome Himiko, our new Lyman-alpha Overlord.
A press release from the Royal Astronomical Society yesterday indicates that astronomers have located some very distant – and therefore very old – signs of water.
The water vapor is thought to be contained in a jet ejected from a supermassive black hole at the center of a galaxy, named MG J0414+0534. The water emission is seen as a maser, where molecules in the gas amplify and emit beams of microwave radiation in much the same way as a laser emits beams of light.
“The radiation that we detected has taken 11.1 billion years to reach the Earth. However, because the Universe has expanded like an inflating balloon in that time, stretching out the distances between points, the galaxy in which the water was detected is about 19.8 billion light years away,” explained Dr. McKean.
Why is this cool? Well, because it tells us something about what the universe was like when it was only a fifth as old as it is now.
“This detection of water in the early Universe may mean that there is a higher abundance of dust and gas around the super-massive black hole at these epochs, or it may be because the black holes are more active, leading to the emission of more powerful jets that can stimulate the emission of water masers. We certainly know that the water vapour must be very hot and dense for us to observe a maser, so right now we are trying to establish what mechanism caused the gas to be so dense,” said Dr. McKean.
Wait a minute, you say. I thought black holes sucked everything in, even light. How can it be that a supermassive black hole is ejecting something like water so fast that it emits strong electromagnetic radiation?
That’s easy, I say. It’s because while there are powerful gravitational forces around a black hole, it’s only stuff that passes the hole’s event horizon that is (almost) sure to be sucked in.
Three large planets (between 5 and 17 Earth-masses) are known to exist around Gliese 581, a red dwarf star about 20 light years away.
Now a Swiss group has spotted a fourth planet around it. At just 1.9 Earth masses, it’s the smallest planet yet found around a main sequence star. It’s cool that we can confirm the presence of planets that are of similar size to ours.
Found at the nifty Dynamics of Cats.
Remember Kepler, the NASA project that will search for Earth-like planets that might sustain life? You can read updates on its progress here. They’re calibrating the photometer at the time I write this.
Hi! I should be back from my Australian vacation sometime today. I’ll be blogging again in real time real soon.
From ScienceDaily recently:
An international team of astrophysicists using telescopes on the ground and in space have uncovered surprising changes in radiation emitted by an active galaxy. The picture that emerges from these first-ever simultaneous observations with optical, X-ray and new-generation gamma-ray telescopes is much more complex than scientists expected and challenges current theories of how the radiation is generated.
Hi! I’m not really here right now. I’m on vacation in Australia. Through the magic of scheduled blogging, I’ve set a little something I find interesting to be posted each day I’m gone.
2009 is the International Year of Astronomy.
Remember when you were a kid and you found planets and comets and black holes cool? Guess what: they still are. Like many areas of the knowledge it seems that the more we look – and looking is something we’re learning to do better all the time in astronomy – the more questions we find.
Here are some of the neat things going on this year. Why not put a couple in your calendar now?
Our own galaxy, the Milky Way, and the one called Andromeda are on a collision course. In just (!) 4 billion years they’ll slam into each other, creating what somw wags have decided to name Milkomeda. Well, “slam” isn’t perhaps the best word: interstellar spaces means it’s extremely unlikely any stars or planets will actually hit each other, but there’s plenty of gas clouds that’ll cause a shockwave or two.
Read about it and listen about it at the Guardian.