James Keeler discovered IC 4278 on two long-exposure plates of M51 taken in May 1899 with the 36-inch Crossley reflector at Lick Observatory. He noted it was "round; diam = 0.2'; central condensation". It was included in the 1908 Publications of Lick Observatory, Vol VIII, catalogue as #669 of 744 new "nebulae".

900/1200mm - 48" (4/2/11): brighter of two IC galaxies (along with IC 4277) very near M51. This small galaxy is located just 6.7' NW of the center of M51 and 5' ESE of NGC 5195. At 488x it was easily visible as a faint, small, round glow, 12" diameter, contains a small bright core. About 2' N is a triangle of mag 13.3/15.5/16 stars (sides 1'-1.5').

Notes by Steve Gottlieb