Dark matter, a mysterious and perhaps-undetected-until-now substance said by scientists to make up 90 percent of the universe, may have been found for the first time on Earth, at the bottom of a mine in Soudan.
The Earth-bound discovery -- if it turns out to be a discovery -- took place at the Soudan Underground Lab particle physics laboratory's Cryogenic Dark Matter Search project. The facility, run by the University of Minnesota, is about 225 miles north of Minneapolis, between Virginia and Ely.
NASA says it discovered proof of dark matter in space in 2006.
In CDMS, physicists use powerful detection equipment to detect dark matter clues on ultracold silicon and germanium crystals, each the size of a hockey puck, located deep underground to avoid interference from background cosmic radiation. Physicists have tried in vain to identify dark matter on Earth since the 1930s, and there have been false alarms about its discovery before.
The gossip mill went into overdrive after a rumor leaked out that the CDMS collaboration has had a paper accepted by the journal Nature. Word is that the paper will appear in the 18 December issue.
Nature is an unusual place for particle physicists to publish their papers and this has prompted speculation that the news must be big.
Here's an explanation of dark matter from the NASA's Goddard Space Flight Center:
There is five times more material in clusters of galaxies than we would expect from the galaxies and hot gas we can see. Most of the stuff in clusters of galaxies is invisible and, since these are the largest structures in the Universe held together by gravity, scientists then conclude that most of the matter in the entire Universe is invisible. This invisible stuff is called 'dark matter'. There is currently much ongoing research by scientists attempting to discover exactly what this dark matter is, how much there is, and what effect it may have on the future of the Universe as a whole.
And here's a video explanation, via Nova: