We present results from a 47 ks observation of the Andromeda galaxy , M31 , using the High-Resolution Camera of the Chandra X-Ray Observatory .
We detect 142 point sources spanning three orders of magnitude in luminosity , from L _ { X } = 2 \times 10 ^ { 35 } erg s ^ { -1 } to L _ { X } = 2 \times 10 ^ { 38 } erg s ^ { -1 } in the 0.1-10 keV band .
The X-ray source location accuracy is better than 1 \arcsec in the central regions of the galaxy .
One source lies within 1.3 \arcsec of SN 1885 but does not coincide with the UV absorption feature identified as the supernova remnant .
However , there is an optical transient , which is likely an optical nova , at the location of the X-ray source .
There is a weak source , L _ { X } \sim 4 \times 10 ^ { 36 } erg cm ^ { 2 } s ^ { -1 } , coincident with the nucleus of M31 , and 14 sources coincident with globular clusters .

Our observation has very high efficiency down to luminosities of 1.5 \times 10 ^ { 36 } erg s ^ { -1 } for sources within 5 \arcmin of the nucleus .
Comparing with a ROSAT observation made 11 years earlier , we find that 0.46 \pm 0.26 of the sources with L _ { X } > 5 \times 10 ^ { 36 } erg s ^ { -1 } are variable .
We find no evidence for X-ray pulsars in this region , indicating that the population is likely dominated by low-mass X-ray binaries .
The source density radial profile follows a powerlaw distribution with an exponent of 1.25 \pm 0.10 and is inconsistent with the optical surface brightness profile .
The x-ray point source luminosity function is well fitted by a differential broken powerlaw with a break at a luminosity of ( 4.5 ^ { +1.1 } _ { -2.2 } ) \times 10 ^ { 37 } erg s ^ { -1 } .
The luminosity function is consistent with a model of an aging population of X-ray binaries .