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Explained in 60 Seconds and News (page 4)
Marusa Bradac
Dark matter is, mildly speaking, a very strange form of matter. Although it has mass, it does not interact with everyday objects and it passes straight through our bodies. Physicists call the matter dark because it is invisible.
Yet, we know it exists. Because dark matter has mass, it exerts a gravitational pull. It causes galaxies and clusters of galaxies to develop and hold together. If it weren’t for dark matter, our Galaxy would not exist as we know it, and human life would not have developed.
Dark matter is more than five times as abundant as all the matter we have detected so far. As cosmologist Sean Carroll says, “Most of the Universe can’t even be bothered to interact with you.” Whatever dark matter is, it is not made of any of the particles we have ever detected in experiments. Dark matter could have — at the subatomic level — very weak interactions with normal matter, but physicists have not yet been able to observe those interactions.
Experiments around the world are trying to detect and study dark matter particles in more direct
ways. Facilities like the Large Hadron Collider
could create dark matter particles.
Comments about this article
mike miller
16 Nov 2008, 16:26
well, baryonic dark matter is significant, of course, but that's not the
mystery.
the late bodhan pyzinsky (sic!) of Princeton U. (sorry about the spelling
all you Poles) went after calculating baryonic dark matter, and it only
added up to about 6% (if I am not mistaken). The mystery of dark matter is
that a much vaster amount of gravitic effects come from something that
doesn't seem to be baryonic matter.
I have my theories on it....
how can photons travel through space masslessly? that's a clue....
JORGE A. ORGANISTA
05 Dec 2007, 22:43
1.How do you know that DM exit?. and
2. DM is like the Ether as old people talked.?
Thanks
mike miller
31 Oct 2007, 18:15
that's a good point about baryonic dark matter; it's in the mix and needs
to be counted too.
But aren't there theories to explain the gravitational effects that
astronomers observe that state the cause as coming from OUTSIDE our
universe? Rather than simply chalk up dark matter as WIMPS waiting to be
discovered, ought not astronomy communicators also include the possibility
that other universes are interacting with ours?
Bruce Dorminey
30 Oct 2007, 10:16
This is a concise explanation of non-baryonic dark matter, but fails to
mention dark matter which is baryonic; or simply dark matter made up of
heretofore undetected low mass stars, white dwarfs and other baryonic
celestial matter. As a science journalist, it was my understanding that
although this would make up only a small portion of dark matter, it is
nonetheless significant. Am I wrong in this assertion?
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