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

Astronomers investigated the properties of a gas on a spatial scale comparable to a typical distance,

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

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

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.