Comments on: NASA Announces Dark Matter Discovery http://www.arsmathematica.net/2006/08/15/nasa-announces-dark-matter-discovery/ Dedicated to the mathematical arts. Fri, 29 May 2015 09:17:44 +0000 hourly 1 https://wordpress.org/?v=4.1.41 By: Ars Mathematica » Blog Archive » Dark Matter, apparently not modern-day epicycles after all http://www.arsmathematica.net/2006/08/15/nasa-announces-dark-matter-discovery/#comment-1385 Tue, 22 Aug 2006 03:55:03 +0000 http://www.arsmathematica.net/archives/2006/08/15/nasa-announces-dark-matter-discovery/#comment-1385 […] Well, John Baez was right, the mysterious NASA press release about a dark matter discovery was about the Bullet Cluster. […]

]]> By: Kea http://www.arsmathematica.net/2006/08/15/nasa-announces-dark-matter-discovery/#comment-1381 Fri, 18 Aug 2006 05:33:42 +0000 http://www.arsmathematica.net/archives/2006/08/15/nasa-announces-dark-matter-discovery/#comment-1381 So-called Dark Matter is extremal black holes, and therefore they will have some nice pictures.

]]> By: jcbaez http://www.arsmathematica.net/2006/08/15/nasa-announces-dark-matter-discovery/#comment-1380 Thu, 17 Aug 2006 04:28:07 +0000 http://www.arsmathematica.net/archives/2006/08/15/nasa-announces-dark-matter-discovery/#comment-1380 For more information, including a picture of the Bullet Cluster, see week238 of This Week’s Finds.

In fact what’s colliding are not galaxies but two whole clusters of galaxies.

]]> By: jcbaez http://www.arsmathematica.net/2006/08/15/nasa-announces-dark-matter-discovery/#comment-1377 Wed, 16 Aug 2006 09:07:19 +0000 http://www.arsmathematica.net/archives/2006/08/15/nasa-announces-dark-matter-discovery/#comment-1377 Since one of the folks at the teleconference is Maxim Markevitch, I bet this is about the Bullet Cluster 1E0657-56 – he used Chandra to study this. These are some colliding galaxies where the gas crashed to a halt and got really hot, while the dark matter kept going straight through! The Chandra observatory shows the X-rays from the hot gas. They can see the dark matter with gravitational lensing – it bends the light from galaxies further back.

This is not completely new, since Markevitch spoke about it in November last year. Also last year people found signs of galaxies made almost entirely of dark matter.

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