The Galactic Center GeV Excess (GCE) is an unexpected surplus of gamma-ray radiation in the center of the

Milky Way The Milky Way or Milky Way Galaxy is the galaxy that includes the Solar System, with the name describing the #Appearance, galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars in other arms of the galax ...

Galaxy. This spherical source of radiation was first detected in 2009 by the Fermi Gamma-ray Space Telescope and is unexplained by direct observation. Two percent of the gamma ray radiation in a 30° radius circle around the Galactic Center is attributed to the GCE. , this excessive (and diffused) gamma-ray radiation is not well understood by astronomers. Some astronomers argue that self-annihilating dark matter (which is not otherwise known to radiate) may be the cause of the GCE, while others prefer a population of pulsars (which have not been observed) as the source. Astronomers have suggested that self-annihilating dark matter may be a dominant contributor to the GCE, based on analysis using non-Poissonian template fitting statistical methods, wavelet methods, and studies by other astronomers may support this idea. More recently, in August 2020, other astronomers have reported that self-annihilating dark matter may not be the explanation for the GCE after all. Other hypotheses include ties to a yet unseen population of millisecond pulsars or young pulsars, burst events, the stellar population of the galactic bulge, or the Milky Way's central supermassive black hole.

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