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NGC 6591 (15,027 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 6591

NGC 6591, LEDA 61610, GC 5905

RA: 18h 14m 3.5s
Dec: +21° 03′ 48″

Con: Hercules
Ch: MSA:1200, U2:159, SA:8

Ref: NGC/IC, Corwin (2004)

(reference key)

Type: galaxy, S

Mag: B=16.3, V=15.5

Size: 0.3′ x 0.1′
PA: 95°

History and Accurate Positions for the NGC/IC Objects (Corwin 2004)

NGC 6591 may be the galaxy that I've flagged with a question mark in the table. That matches Marth's description ("eeF, vS, stell") and is not too far off his position (the RA is 12 seconds too large). However, it may not be the object that Marth saw.

That object was found the same night as NGC 6586 which has offsets from Marth's position of -2 seconds of time and -14 arcsec in declination. At similar offsets (-3 seconds and -32 arcsec) is a faint galaxy with two foreground stars just to the southwest, the brighter star superposed on the galaxy itself. While this group of objects does not match Marth's description -- in particular, the galaxy is fainter than the one I mentioned in the previous paragraph, and the brighter superposed star is considerably brighter than the galaxy (why didn't Marth mention the star if he saw it?) -- its positional coincidence within Marth's usual observational errors is fairly compelling.

Still, I'm keeping open the possibility that the brighter, isolated galaxy is Marth's object. It may even be possible that the asterism of five stars that I've also included in the table is the object that Marth saw. But that is the least likely option because its brightest star is nearly of the 10th magnitude, far too bright to match Marth's description.

Published comments

Sulentic & Tifft (1973)

The RNGC (Sulentic and Tifft 1973) notes that this is a galaxy. Their coded description reads SLEL,BM,RI*FIELD.

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