MESSIER 31 || Fermi Detects Gamma-ray Puzzle from M31

Fermi Detects Gamma-ray Puzzle from M31

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. Gamma rays are the highest-energy form of light, produced by the universe's most energetic phenomena. They're common in galaxies like the Milky Way because cosmic rays, particles moving near the speed of light, produce gamma rays when they interact with interstellar gas clouds and starlight. 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. NASA's Fermi telescope has detected a gamma-ray excess at the center of the Andromeda galaxy that's similar to a signature Fermi previously detected at the center of our own Milky Way. Watch to learn more. Credit: NASA's Goddard Space Flight Center/Scott Wiessinger Music: "Lost Time" from Killer Tracks For more information: https://www.nasa.gov/feature/goddard/2017/nasas-fermi-finds-possible-dark-matter-ties-in-andromeda-galaxy This video is public domain and along with other supporting visualizations can be downloaded from the Scientific Visualization Studio at: http://svs.gsfc.nasa.gov/12505 If you liked this video, subscribe to the NASA Goddard YouTube channel: http://www.youtube.com/NASAExplorer Or subscribe to NASA’s Goddard Shorts HD Podcast: http://svs.gsfc.nasa.gov/vis/iTunes/f0004_index.htmlFollow NASA’s Goddard Space Flight Center · Facebook: http://www.facebook.com/NASA.GSFC · Twitter http://twitter.com/NASAGoddard · Flickr http://www.flickr.com/photos/gsfc/ · Instagram http://www.instagram.com/nasagoddard/ · Google+ http://plus.google.com/+NASAGoddard/posts