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Type: galaxy (Seyfert 2), SBb
Mag: B=15.4, V=?
Size: 1.202′ x 0.389′
NGC 6393 and NGC 6394 are a pair of objects found 7 July 1885 by Lewis Swift. Though he describes the two as equally faint, the southern of the two objects on the sky (more than 6 arcmin south of his position) is much fainter than the northern (3.5 arcmin south of the nominal position). I'm not convinced that Swift could have seen it.
In fact, he did not find it again. When he went over the field on 15 June 1890, he recovered only one of the galaxies. This time, his position was virtually identical to the one that he gave for N6393, leading Dreyer to omit it from IC1. The position is also close to the true position for the brighter galaxy.
This brighter galaxy has been taken by MCG and CGCG as N6393 based on the position. However, Swift's description does not match the field. Swift says, "vvF, pS, R; 2 B sts nr n; s of 2." The comment about the two bright stars north matches the fainter southern galaxy, but not the brighter northern one. For his northern object, Swift says, "vvF, pS, R; 2 sts point to it, the nearer is D; the other and the neb. are equally distant from the D *; n of 2." For the record, his 1890 observation reads, "eeF, pS, cE; B * nearly obscures it; between it and a F*, nearer the latter."
This matches what is on the sky pretty well (his double star in the first observation is the "B *" in the second, and the other two stars are there also), so I have taken NGC 6394 as the northern galaxy. I have also tentatively assigned NGC 6393 to the very faint southern object since there is no other candidate object nearby. There are many other galaxies within one or two degrees, but none have the stars near that Swift describes. Whatever he saw, it clearly needs visual confirmation.
The RNGC (Sulentic and Tifft 1973) notes that this is a 15.5 mag galaxy. Their coded description reads EL,BM.
The Messier objects
The Bennett objects
The Caldwell list
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