Half the Universe's Missing Matter Has Just Been Finally Found (newscientist.com)

An anonymous reader shares a report: The missing links between galaxies have finally been found. This is the first detection of the roughly half of the normal matter in our universe -- protons, neutrons and electrons -- unaccounted for by previous observations of stars, galaxies and other bright objects in space. You have probably heard about the hunt for dark matter, a mysterious substance thought to permeate the universe, the effects of which we can see through its gravitational pull. But our models of the universe also say there should be about twice as much ordinary matter out there, compared with what we have observed so far. Two separate teams found the missing matter -- made of particles called baryons rather than dark matter -- linking galaxies together through filaments of hot, diffuse gas. "The missing baryon problem is solved," says Hideki Tanimura at the Institute of Space Astrophysics in Orsay, France, leader of one of the groups. The other team was led by Anna de Graaff at the University of Edinburgh, UK. Because the gas is so tenuous and not quite hot enough for X-ray telescopes to pick up, nobody had been able to see it before.

Comments

Re:Dark matter

[dryeo]

You should check out the history of the discovery of the neutrino, a particle invented to make the maths work given our assumptions. Also very similar to dark matter as it barely interacts with normal matter.
Interestingly when Fermi refined the theory giving a neutrino, Nature refused to publish it as too far out there.
https://en.wikipedia.org/wiki/...

The positron also was theorized first on the basis that Dirac's new theory allowed it. Though at first it wasn't considered as a new particle. https://en.wikipedia.org/wiki/...