It’s the 10th anniversary of dark matter’s most compelling proof.
“It may be that ultimately the search for dark matter will turn out to be the most expensive and largest null result experiment since the Michelson-Morley experiment, which failed to detect the ether.” –John Moffat
If you look at rotating galaxies or the motions of galaxies within clusters, there’s a mismatch between the matter we see and the gravitational effects we observe.
Even on the largest scales, the way galaxies clump and cluster together cannot be explained without some new physics.
Observations show that it can’t be gas, dust, plasma or black holes; there’s truly something unaccounted for.
Attempts to modify gravity can solve some of these problems, but the leading explanation is a new type of matter: dark matter.
For a long time, these two possible explanations fought for dominance, but in 2006, dark matter emerged victorious.
Two colliding galaxy clusters were caught in the act by multiple telescopes, including Hubble and Chandra.
The X-ray observatory showed that the colliding gas and plasma, made of normal matter, heated up and slowed down.
Yet mass reconstructions from gravitational lensing show that most of the matter passed right through.
This mismatch between where the matter is located and where the gravitational effects are has now shown up in many colliding clusters, independently.
This empirical proof of dark matter cannot be explained by any theories of modified gravity.
Mostly Mute Monday tells the story of a single astronomical phenomenon or object in visuals, images and video in no more than 200 words.
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