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Dark Matter Discovered
sebFlyte writes "Wired is reporting that scientists have come up to a solution as to where all the matter in the universe actually is. Experiments being done with Chandra, NASA's X-ray telescope have shown up a likely candidate for the solution of the dark matter problem. There are massive quantities of Baryons in a super-heated gas cloud several hundred million light years away."
In physics we don't call it dark matter. We call it "make the theory fit the data" matter.
This should be "Missing Matter Discovered" not "Dark Matter Discovered"
They HAVE NOT found dark matter, they've found the 'missing matter' as the article says. They have found a clue as to the dark matter, as a result of the discovery.
Although discovering the dark matter would be much cooler, (yeah I was excited when I read the title).
[rant] Why is it the only 3 times I've 'emailed the on duty editor' before publishing, I've been ignored and the mistakes gone through?? [/rant]
Windows in 6 Bytes (IA-32) : 90 90 90 90 CD 19
You seem to be under the impression that we know what dark matter is and isn't. Dark matter is postulated given gravitational effects that would arise from mass that we cannot detect, hence dark.
If it turns out that it is normal matter after all, and we just had trouble seeing it, we have still "discovered dark matter."
Another way of putting it would be, who killed the prime minister of Georgia? If it turns out later that it was an accident from a faulty space heater, did we find out who killed him? Just becuase we were expecting a who and got a what doesn't mean the question wasn't answered.
In other words, if regular stuff is about 5% of the energy density of the universe, with dark matter at about 20%, and dark energy at about 75% -- the stuff in this story comes into that 5%, ie, regular stuff and not dark matter.
Here's what I do: Bitty Browser & Andromeda
At least there were, several hundred million years ago.
slashdot broke my sig
First, this result only applies to BARYONIC dark matter, which is only a fraction of all the dark matter out there. Second, we already knew that a lot of it at the epochs in question was in the form of hot intercluster gas.
The current work is an improvement over previous studies, and is good work. But the headline rather sucks. I thought we'd detected axions or something, even though I'd already read about this result.
I teach techniques to estimate cluster masses based on X-ray emission, and have used the Chandra X-ray Observatory myself. A headline about such work shouldn't trick me.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
If you just think astrophysics is math, you'd flunk the heck out of my astronomy exams no matter your mathematical sophistication. Probably every level of astronomy, from non-major to graduate level. At least the way I teach it.
Math is a very useful tool in astrophysics, but there's a reason that math is a separate department from any physical science.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)