In article ,
jacobnavia writes:
An important "proof" for dark matter has vanished: Astronomers take back
the observation that a cluster was missing its dark matter, "left
behind".

That is a very strange way of stating the result. Previous
observations had suggested an offset between the dark matter and
visible stars for one of the four cluster galaxies. The new data
show no evidence of an offset. Either morphology is consistent with
existing theory; there is no "proof" for dark matter involved.

The derived dark matter masses associated with each galaxy are
uncertain but roughly 10 times the stellar masses.

Royal Astronomical Society. "Dark matter might not be interactive after
all." ScienceDaily. ScienceDaily, 5 April 2018.
www.sciencedaily.com/releases/2018/04/180405223407.htm.

The preprint is at
https://arxiv.org/abs/1708.04245
The refereed journal article will be published in MNRAS on Apr 15.

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