Lewis Swift discovered NGC 6393 = Sw. I-64, along with NGC 6394 and 6399, on 7 Jul 1885. His description for NGC 6393 reads "vvF, pS, R, 2 B st nr north; south of 2" and for NGC 6394, "vvF, pS, R, 2 st point to it, the nearest is D[ouble]; the other and the nebula are equally distant from D star; north of 2." The description of NGC 6394 is a perfect match UGC 10889 and NGC 6393 is possibly MCG +10-25-054. The (unequal) double star is HD 159266, located 3.9' NW of NGC 6393. This star is midway between NGC 6393 and a mag 11 star further NW. Swift found the northern galaxy NGC 6394) again on 15 Jun 1890 and included it in list IX-81, this time at the correct position. The identification NGC 6393 = MCG +10-25-054 is uncertain as the separation in declination between the pair is 6.5', while Swift's gives just 3.5' and MCG +10-25-054 is perhaps too faint for Swift to have picked up with his 16-inch (see my visual description). Edward Fath first suggested NGC 6393 may be MCG +10-25-054 (No. 789 in Table 1) and NGC 6394 may be UGC 10889 (No. 791 in Table 1) in his 1914 paper "A Study of Nebulae".

Swift's poor declination for NGC 6393 coincidentally matches UGC 10889. As a result, all modern galaxy catalogues misidentify UGC 10889 as NGC 6393. RNGC and PGC reverse the identifications of NGC 6393 and NGC 6394, labeling the fainter southern galaxy as NGC 6394. MCG does not attach a NGC label to MCG +10-25-054. See Harold Corwin's notes for NGC 6394.

400/500mm - 17.5" (6/18/88): not found

Notes by Steve Gottlieb