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."

Comments

Not quite...

[Anonymous Coward]

The summary is not correct (big surprise there) in that this is a confirmation of a long-suspected theory as to where the missing ordinary (baryonic) matter in the universe is. This does not solve the dark matter problem at all.

Read more at the press release from the Chandra team at Marshall: http://www.spaceref.com/news/viewpr.html?pid=16049

Dark matter is yet another topic altogether, as is the even more elusive dark energy.

Re:Baryons

[FalconZero]

In case anyone's wondering what slashdot is...

http://www.slashdot.org/

Can I have my +5 informative now??

Re:Aren't baryons just normal matter?

[randominator]

Tachyons are in fact hypothesized faster-than-light-particles, appearing for instance in certain string theory scenarios.

But baryons are by no means the counterpart to tachyons. All known elementary particles in the universe are either fermions (particles with spin in integer multiples of 1/2) or bosons (particles with integer spin). Bosons include the photon, the gluon and many others. The fermions are further subdivided into leptons and quarks. Leptons include the electron and the electron neutrino among others. Baryons are particles made up of three quarks, and are fermions and include among others, the proton and neutron, which are the most commonly found baryons in nature, since all heavier baryons normally decay.

Two quarks (fermions) can combine to form mesons, which are in fact bosonic in nature (since two quarks with spin half combine to form a particle with integer spin).

Hope that confused the issue a little :-)

A bit more on-topic: Finding baryons in this amount is a big deal, since baryon has previously been suspected to primarily exist in galaxies, and only in small amounts outside galaxies. While it by no means doesn't solve all problems of cosmology, it is a big help.

Re:Wait a sec, this story isn't about "dark matter

[mbrother]

Yeah, at least part of them. You can go to my website above, hit "Astronomy Work" link on the left, and be taken to http:physics.uwyo.edu/~mbrother where you'll find links to three recent courses I've taught. The intro astronomy course (1050) is currently in session and so the slides for that one are incomplete. These are slides, meant to accompany lecture, so they aren't enough on their own, but you might enjoy looking anyway.