New HST observations show that the bright X-ray source in the face-on spiral galaxy NGC 1073 is located near a ring of recent star formation with an age of 8–16 Myr .
This strengthens the association of X-ray sources in spiral galaxies emitting near or above the Eddington limit for a 20 M _ { \odot } black hole with recent star formation events .
Two candidate optical counterparts of the X-ray source are found .
The X-ray to optical flux ratios of both are consistent with those of low-mass X-ray binaries and higher than most high-mass X-ray binaries , suggesting that reprocessing of X-rays contributes to the optical light .
The optical magnitude and color of one candidate is consistent with that predicted for an X-ray binary with an initial donor mass of 6 - 8 M _ { \odot } .
However , the same X-ray binary evolution model underestimates the X-ray luminosity .
An X-ray source list for the field is presented which includes detections of the nucleus of NGC 1073 , three quasars , and an M3e brown dwarf star with high proper motion .