Some years ago I read that a mass of hot (1 million degree) gas was detected between the galaxies in the Virgo cluster. It was not considered enough to make up the famous “missing mass,” but this new discovery indicates that there could be substantially more, just diffuse and undetectable at that distance. If the need to postulate mysterious “dark matter” were to disappear, would this affect theories about dark energy?
Other questions arise: Why is this gas so hot, and if it is radiating energy in the form of x-rays, how does it stay so hot? A giant mass of plasma surrounding our galaxy would be a giant, spherical conductor. How would electro-magnetic currents behave within it? How could we detect them?
This discovery is potentially a very big eye-opener.