NGC/IC Project Restoration Effort
(This is a very very beta version)
NGC3518
Basic Information
Location and Magnitude
Right Ascension: 10:4:1.9
Declination: -6:28:29
Constellation: SEX
Visual Magnitude: 12.2
Historic Information
Discoverer: Stone
Year of discovery: 1885
Discovery aperture: 26.3
Observational
Summary description: eF, eS, lE
Sub-type: Sb
Corwin's Notes
=====
NGC 3518 = NGC 3122 = NGC 3110. In the original AJ paper, Stone notes, "In
same field with nebula discovered by Stephan." This is a bit puzzling as
none of Stephan's nebulae are within 5 degrees of Stone's nominal position.
Stone has left us a sketch, too, with the same nominal position on the cover
sheet. The sketch shows a nice double nebula with four stars nearby. Again,
there is nothing on the sky within 5 degrees of the nominal position that
matches the sketch.
So, I assumed some sort of error in Stone's position and began looking at
possible digit errors. After ruling out a few, I found NGC 3122 in Stephan's
13th list (it is number 54 there) just an hour of time preceding Stone's
position. Checking his sketch against the PSS, I found that the "double
nebula" is actually the central bulge, and a very bright arm to the
southeast, of a single galaxy. Furthermore, one of the "stars" sketched by
Stone is the nucleus of an interacting companion galaxy, MCG -01-26-013. Were
it not for the sketch, I would assign the NGC number to this companion (though
the position angle is more than 20 degrees off Stone's estimate of 110 deg).
As is, I am tempted to put the number on just the arm -- but that does not
match Stone's description, either. By default, then, N3518 = N3122 = N3110
(which see for another story).
Steve's Notes
=====
NGC 3518
See observing notes for NGC 3110. One hour error in RA in Stone's position.