Fermi finds possible dark matter ties in Andromeda galaxy
https://phys.org/news/2017-02-fermi-dark-ties-andromeda-galaxy.html
NASA's Fermi Gamma-ray Space Telescope has found a signal at the center of the neighboring Andromeda galaxy that could indicate the presence
of the mysterious stuff known as dark matter. The gamma-ray signal is similar to one seen by Fermi at the center of our own Milky Way galaxy.
Surprisingly, the latest Fermi data shows the gamma rays in Andromeda—also known as M31—are confined to the galaxy's center instead of spread
throughout. To explain this unusual distribution, scientists are proposing that the emission may come from several undetermined sources. One
of them could be dark matter, an unknown substance that makes up most of the universe.
"We expect dark matter to accumulate in the innermost regions of the Milky Way and other galaxies, which is why finding such a compact signal
is very exciting," said lead scientist Pierrick Martin, an astrophysicist at the National Center for Scientific Research and the Research
Institute in Astrophysics and Planetology in Toulouse, France. "M31 will be a key to understanding what this means for both Andromeda and
the Milky Way."
