Spitzer has an interesting press release...
The Spitzer infrared space observatory recently did followup imaging of a type II supernova in the nearby spiral galaxy M74.
Type II supernovae occur when a short lived massive star (> 8 times the mass of the Sun, or so) exhaust the fusionable fuel in their core, and the core collapses to a neutron star, with the outer layers of the star blown off in a very spectacular explosion.
To cut a long story short, the supernova remnant is full of hot dust, when imaged in the infrared.
paper on Science Express
This is a step to solving a puzzle. The early universe, starting just a few hundred million years after the Big Bang, is surprisingly dusty, with much of the star formation in the early universe shrouded in dense dust clouds.
We have long known of two certain dust sources: dust could aggregate from cold molecules in interstellar space, since the interstellar medium is rather low density, this is a slow process. The second source is the outflow from "AGB" stars. Bright red giant stars, of intermediate mass (few times the mass of the Sun), whose cores have exhausted hydrogen for fusion and are fusing helium in the layer outside the stellar core. This causes the star to swell and a slow outflow to come off the surface of the star, (eventually becoming Planetary Nebulae).
The AGB wind is perfect for forming refractory micron sized dust, it is metal enriched, dense, cool and slowly expanding. AGB outflows are probably the source of much of the dust in galaxies.
But, they take time to get started, maybe 1-2 billion years. So AGB outflows can not account for dust in the early universe.
The conjecture had been that dust would form in the cooling blast wave from type II supernovae and that this would explain the dust in the early universe, but this was hard to understand and not observed. Well, now we have a good observation showing this occuring.
And, dust makes planets...
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Hey Steinn -- congrats on the move to your new digs. Still a few flakey things. The eth in your name is coming out with a capital A with a squiggle over it and a degree sign. Is that just my non-MS operating system and fonts?
Gee, posh digs!
Two things. I thought people had already seen dust formation in the 1987A remnant. Second, the ad on the page was for a discovery channel special on volcanos, which had a picture of huge dust plume, strikingly appropriate.
Have you seen this article on the meteorite that recently hit Norway? I'm surprised there are no photos of the impact site or any other data about it yet. Have you heard anything?
http://www.aftenposten.no/english/local/article1346411.ece
The flaky ð vs � (did that work?) are probably due to MT defaulting to some iso extension other than latin-1. Bastards. Will check.
Lots of housekeeping to do. Seed Mag does not seem to be aware of NASA proposal deadlines, strangely enough.
Reading the paper 87a and 99em (didn't know that) showed evidence of dust, but a total inferred mass was several orders of magnitude too small to account for high-z dust.
This one made lots of dust.
So, that's kinda exciting...
Anyway, I'm sure Zwicky did it first...
Mara, thanks for that tip.
Very interesting and looks real.
Will put an entry on it soon as I gather some info.