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We confirm our earlier tentative detection of M31* in X-rays and measure itslight-curve and spectrum. Observations in 2004-2005 find M31* rather quiescentin the X-ray and radio. However, X-ray observations in 2006-2007 and radioobservations in 2002 show M31* to be highly variable at times. A separatevariable X-ray source is found near P1, the brighter of the two optical nuclei.The apparent angular Bondi radius of M31* is the largest of any black hole, andlarge enough to be well resolved with Chandra. The diffuse emission within thisBondi radius is found to have an X-ray temperature ~0.3 keV and density 0.1cm-3, indistinguishable from the hot gas in the surrounding regions of thebulge given the statistics allowed by the current observations. The X-raysource at the location of M31* is consistent with a point source and a powerlaw spectrum with energy slope 0.9+/-0.2. Our identification of this X-raysource with M31* is based solely on positional coincidence.

X-ray and Radio Variability of M31*, The Andromeda Galaxy Nuclear Supermassive Black Hole