Dark matter `seen for first time`

Planetary scientists believe they may have finally caught the first glimpse of dark matter.

Updated: Feb 12, 2010, 11:36 AM IST

London: For over 80 years, it has eluded
the finest minds in science. Now, planetary scientists believe
they may have finally caught the first glimpse of dark matter,
the mysterious hidden substance accounting for three-quarters
of matter in the universe.

No one knows what it is, but physicists came up with
the theory of dark matter to explain strange anomalies in the
rotational speed and clustering of galaxies. It is believed to
have played a central role in the evolution of galaxies and
large scale structure of the universe.

Now, after nine years of searching, detectors buried
some 2,000 feet underground in Cryogenic Dark Matter Search II
(CDMS II) observatory, located half-a-mile underground in the
disused Soudan iron mine in Minnesota, registered two "hits"
by what could turn out to be dark matter particles.

Both bear the hallmarks of the "weakly interacting
massive particles" or "Wimps", one of the most likely dark
matter candidates, according to the scientists.

Though two detections, published in the latest edition
of the `Science` journal, are not quite enough to clinch the
discovery, they believe five detections will be sufficient to
confirm the presence of Wimps.

"With one or two events, it`s tough. The numbers are
too small. Many people believe we are extremely close -- not
just us, but other experiments.

"It is expected or certainly hoped that in the next
five years or so, someone will see a clear signal," `The Daily
Telegraph` quoted Dr Tarek Saab of University of Florida, one
of the physicists working on CDMS II, as saying.