NGC 731 is an elliptical galaxy located in the constellation of Cetus about 172 million light-years away from the Milky Way. It was discovered by William Herschel on January 10, 1785. It has a luminosity of 3.9×1010 L☉.

400/500mm - 17.5" (11/6/93): fairly faint, small, round, broad concentration. A mag 13 star is 2.5' SW.