Édouard Stephan discovered NGC 2398 = St XIII-29 on 10 Feb 1885 with the 31-inch reflector at Marseilles Observatory. His position is accurate.

Stephane Javelle resolved it into a double nebula on 7 Feb 1896 and made a footnote in his listing for IC 2191 = J. 3-1000 that NGC 2398 appears double". Dreyer didn't assign CGCG 117-046 an IC designation as Javelle didn't note an offset or position, though he commented in the IC 2 Notes section "seems to be a double neb (Javelle III.)

400/500mm - 17.5" (2/8/91): faint, small, elongated 3:2 WNW-ESE, broad concentration, stellar nucleus.

600/800mm - 24" (2/14/15): faint to fairly faint, small, very slightly elongated, 20"x16", nearly even surface brightness. A mag 15 star is off the northwest edge [23" from center].

Forms a very close pair with CGCG 117-046 off the west-northwest side [40" between centers]. At 375x, the companion appeared extremely faint and small, round, 8" diameter (core only), visible ~1/3 of time with concentration. IC 2191 lies 10' S and is fairly faint, small, slightly elongated SSW-NNE, 20"x15", contains a very small brighter nucleus.

Notes by Steve Gottlieb