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Mystery deepens in galaxy cluster A520


15:06, March 06, 2012

BEIJING, March 6 (Xinhuanet) -- Dark matter doesn't usually collide much with itself or with ordinary matter, but it appears to be uncharacteristically clumping in the galaxy cluster A520, said a study in the Astrophysical Journal quoted by media reports Tuesday.

Dark matter only makes its presence felt through its gravitational pull and astronomers have figured out ways to ID dark matter.

One tactic is called gravitational lensing. Dark matter’s gravitational pull bends light, so clumps of dark matter distort the appearance of galaxies in the background.

Researchers measured those distortions with the Hubble Space Telescope. And they recently mapped out the dark matter in a galaxy cluster called A520, which is actually several galaxy clusters, all smashing together.

The problem is the dark matter in A520 wasn’t where it ought to be.

Past studies have shown that clouds of dark matter passed cleanly through one another when galaxy clusters merged. That’s because dark matter doesn’t collide much with itself or with ordinary matter.

But in this case the dark matter seemed to bunch up in the middle, as if it was sticking together.


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fool at 2012-03-06117.242.144.*
space is good thing now time has come for launching space navigation system,galaxy navigation system,construction of galactor,interplanets defense agreements,planetary excercises .and more advance techniques like pressure points in earth orbit.and controlling earth rotation speeds,should begin,interplanetary gravitational control technology is also parttechnological high end transfers should start and surpass everybody wildest dream and imagination and all world supercomputers combined.everybody who like china shld do that.

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