George Johnstone Stoney or Bindon Stoney, LdR's assistants, discovered NGC 4001 on 13 Apr 1852. While observing NGC 4010 he noted "A S, R neb about 7' np."

400/500mm - 17.5" (4/7/89): extremely faint, very small but elongation visible NNW-SSE, weak concentration. A mag 12 star is 2.1' N and a mag 11.5 star 4.2' NE of center. Located 6' NW of NGC 4010.

Notes by Steve Gottlieb