Science News / Clashing Clusters

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Sequencing the dead to save the living: Reviving ancient genomes of long-extinct creatures offers a window into past extinctions—and may help prevent future die outs
No gene is an island: Even as biologists catalog the discrete parts of life forms, an emerging picture reveals that life’s functions arise from interconnectedness
The decider: Informing the debate over the reality of ‘free will’ requires learning something about the lateral habenula
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Clashing clusters

Two galaxy clusters collide to give astronomers a clue about dark matter

By Ashley Yeager

Web edition : Wednesday, August 27th, 2008

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During a clash of galactic clusters, NASA's Chandra X-ray Observatory and Hubble Space Telescope teamed up to produce this composite image, which shows clear evidence for dark matter. Ordinary matter, mostly gases, is shown in pink, dark matter in blue.NASA, CXC, Stanford, S. Allen; Optical-Lensing: NASA, STScI, UC Santa Barbara, M. Bradac

During a clash of galactic clusters, NASA's Chandra X-ray Observatory and Hubble Space Telescope teamed up to produce this composite image, which shows clear evidence for dark matter. With Hubble, astronomers inferred where the dark matter, shown in blue, sits. Chandra mapped the locale of ordinary matter, mostly hot gas, shown in pink. The image reveals that as the two clusters collided, the dark matter sailed right through the normal matter. The find supports the notion that dark-matter particles interact with each other and normal matter weakly, if at all, aside from the pull of gravity.

Found in: Atom & Cosmos

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Comments 2

http://www.nature.com/news/2007/071102/full/news.2007.215.html

(Submitted 2 Nov 2007 to www.submit2science.org.)
The Bullet Collision: Light On Dark Matter?

A. Back to the colliding Bullet cluster of galaxies http://sciencenow.sciencemag.org/cgi/content/full/2007/1031/1 The argument continues...

B. Back to a note a year ago Direct proof of dark matter? http://www.nasa.gov/home/hqnews/2006/aug/HQ_06297_CHANDRA_Dark_Matter.html

Notes 28 Aug 2006

http://blog.360.yahoo.com/blog-P81pQcU1dLBbHgtjQjxG_Q--?cq=1&p=268

Without background knowledge about the subject, but with plain common sense, best scientific approach, this is what I "see" in and conclude from the processed image of the event:

- In order to collide the two clusters (moving in the same spatial course/direction due to universal expansion) must have been moving at different moving rates due to differing cluster's mass and therefore acceleration values.

- As the collision progresses the two (most probably) hydrogenous clusters' atmospheres press against each other.

- what we "see" is that each of the two separate clusters' atmospheres is deformed and displaced, in extent and in shape and characteristics depending on the size of its parent cluster and on the characteristics of its H atmosphere and on the events of the evolution of the 'go-through merger' of the clusters.

- If E of the Universe = the sum of all values of m(1+D), where D is the Distance of m from Big Bang point and the sum is of all spatial values of D from D=0 to D=selected value, then, following Newton (1) gravity is decreased when mass is decreased and (2) acceleration of a body is given by dividing the force acting upon it by its mass. By plain common sense the combination of those two 'laws' may explain the accelerating cosmic expansion of galaxy clusters and the 'laws' that drive it, based on the above E/ m/ D relationship...and may explain the Bullet collision...

Posted by: Dov Henis
03 Nov, 2007

Dov Henis

Sep. 4, 2008 at 1:04am
Why is the dark matter not lagging behind? The current theory says it should react weakly so the assumption is that we're seeing the dark matter being in an advanced position, but the other possibilty needs to be eliminated.

Hiro Sheridan

Aug. 31, 2008 at 8:19am