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In this paper, we report on Chandra observations of the starburst galaxy NGC 922. NGC 922 is a drop-through ring galaxy with an expanding ring of star formation, similar in many respects to the Cartwheel galaxy. The Cartwheel galaxy is famous for hosting 12 ultraluminous X-ray sources (ULXs), most of which are in the star-forming ring. This is the largest number of ULXs seen in a single system and has led to speculation that the low metallicity of the Cartwheel (0.3 Z ☉) may optimize the conditions for ULX formation. In contrast, NGC 922 has metallicity near solar. The Chandra observations reveal a population of bright X-ray sources, including seven ULXs. The number of ULXs in NGC 922 and the Cartwheel scales with the star formation rate: we do not find any evidence for an excess of sources in the Cartwheel. Simulations of the binary population in these galaxies suggest that the ULX population in both systems is dominated by systems with strong wind accretion from supergiant donors onto direct-collapse black holes. The simulations correctly predict the ratio of the number of sources in NGC 922 and the Cartwheel. Thus, it would appear that the metallicity of the Cartwheel is not low enough to see a difference in the ULX population compared to NGC 922.

NGC 300 X‐1 and IC 10 X‐1 have recently been identified in nearby galaxies as extragalactic examples of the rare class of Wolf‐Rayet/compact object X‐ray binary system uniquely exemplified in the Galaxy by Cyg X‐3. Using Swift TOO observations of NGC 300 X‐1 and IC 10 X‐1, we recently discovered very similar periods of 32.8±0.4 and 34.8±0.9 hours, respectively. We believe that these are likely to be orbital periods. It seems surprising that these are so similar and large compared to the short 4.8 hour period of Cyg X‐3, suggesting different evolutionary paths. For both extragalactic candidates we show the allowed ranges of component masses and Wolf‐Rayet star wind velocities for which accretion disks could form around the black holes.