There is an Enormous Halo of Hot Gas Surrounding Our Galaxy

Posted on September 24, 2012

hot_gas_halo_milky_way.jpg


Astronomers using NASA's Chandra X-ray Observatory have found evidence our Milky Way Galaxy is embedded in an enormous halo of hot gas. The hot gas halo extends for hundreds of thousands of light years. Astronomers say the estimated mass of the halo is comparable to the mass of all the stars in the galaxy. The scientists also determined the temperature of the absorbing halo is between 1 million and 2.5 million kelvins, which is a few hundred times hotter than the surface of the sun. The scientists also say in a release that the mass could explain the "missing baryon" problem.

Study co-author Smita Mathur of Ohio State University in Columbus said in a statement, "Our work shows that, for reasonable values of parameters and with reasonable assumptions, the Chandra observations imply a huge reservoir of hot gas around the Milky Way. It may extend for a few hundred thousand light-years around the Milky Way or it may extend farther into the surrounding local group of galaxies. Either way, its mass appears to be very large."

The research was published here in The Astrophysical Journal.

Image: NASA/CXC/M.Weiss; NASA/CXC/Ohio State/A.Gupta et al.