Astronomers determined the viscosity of a gas in a cluster of Coma galaxies. It flows like honey!

Astronomers have studied the properties of gas on spatial scales comparable to typical distances,

which particles travel between collisions with each other. This data helped them determine the viscosity of the hot gas in the cluster - the resistance to the movement of lumps of gas relative to each other.

It is known that the hot gas in Coma containsabout six times the mass of all the combined galaxies in the cluster. Despite its abundance, the density of the hot gas, as radio observations have shown, is so low that the particles do not interact with each other very often.

Such a hot low-density gas cannot be studied in a laboratory on Earth, and therefore scientists must rely on natural space laboratories, such as clusters of galaxies.

The research results show that the viscosityComa gas is much lower than expected. This means that turbulence can easily develop in hot gas in clusters of galaxies on a small scale, similar to the vortex movements in a cup of coffee, which is hampered by a spoon.

Irina Zhuravleva, University of Chicago

Earlier it was reported that physicists from the RoyalKTH Institute of Technology is developing Stacked Prism microlenses - they allow bending of X-rays in a new way. In the future, a network of such lenses will reduce the size of space X-ray telescopes and increase their efficiency.