Thanks for all the info and for answering my questions, Steve! You just
saved me a great deal of weekend homework. <grin>
Looking forward to reading your _Sky_&_Telescope_ article when it's
published, too!
...Bob...
> -----Original Message-----
> From: sf-bay-tac-bounces@No-Spam
> [mailto:sf-bay-tac-bounces@No-Spam] On Behalf Of Steve Gottlieb
> Sent: Thursday, January 30, 2003 5:20 PM
> To: The Astronomy Connection
> Subject: Re: [TAC] OR: Fremont Peak 1/29/03
>
>
> In a message dated 1/30/03, Bob Czerwinski writes:
>
> > I ran into problems locating several items, a couple in Leo
> and one in
> > CVn. Although I'm quite certain I was in the correct positions, I
> > couldn't locate NGC 3498 and 3616 in Leo, nor could I
> properly identify
> > 4401 in Virgo. Here were the problems:
> >
> > 3498: Assuming the coordinates I have are fine, I was able to locate
> > both 3489 and 3485 nearby. 3498 should have formed a nice
> triangle with
> > these two. A surface brightness problem?
>
> Well, the problem here is that NGC 3498 probably does not
> exist!! It was
> reported by William Herschel (III 75) and described as "eF,
> not S. I had
> some doubt and put on 240x, but there being no stars very
> near to it, I could
> not adjust the focus, and therefore could not verify it."
>
> And later highly-respected 19th century observers, including Heinrich
> d'Arrest and Guillaume Bigourdan, could not find it again.
> In the 1926, Karl
> Reinmuth reported (based on a photographic survey of the
> Herschel objects)
> that "In Dreyer's place is vF triple star, *14.7, *14.7, *16,
> a *14.7 f 1.8'
> of *16." That's likely what confused Herschel - a faint
> triple star! Here's
> the position: 11 01 41.5 +14 21 04
>
>
> > 3616: Should have been just outside of the field with Theta
> Leonis, and
> > in the same field with NGC 3596. Again, if the coordinates
> are correct,
> > maybe another SB problem?
>
> This is another lost William Herschel discovery (III 76)
> which could not be
> recovered by Bigourdan with the 12-inch refractor of the
> Paris Observatory or
> in later photographic searches (Max Wolf and Reinmuth). This
> may have have
> just a single faint star at 11 18 08.9 +14 45 53, but I'm
> surprised it is
> listed is some source as a galaxy.
>
>
> > 4401: This is entirely different from the others.
> Coordinates put it
> > right in the middle of the area occupied by NGC 4395, a
> huge haze with
> > two or three HII regions. I identified 4395 with no
> problem, which was
> > best viewed with relatively low magnification. Is 4401
> just one of the
> > HII regions, much like NGC 604 in M33? Is there a separate
> galaxy in
> > that mess?
>
> Ah, this is a very interesting, active galaxy who a number of
> HII knots which
> received separate NGC designation. It is a bit difficult to
> sort out of the
> individual HII masses (which may look like individual
> galaxies!), but there
> is only one galaxy here. This one requires very good
> transparency and seeing
> to make some sense of the view (at least in my 17.5"):
>
> 17.5" (5/15/99): N4395 is a chaotic galaxy dominated by
> several bright HII
> regions. At 100x, the large low surface brightness glow is
> clearly clumpy
> with a couple of faint knots evident on the east side of the
> haze. At 220x,
> the glow of the galaxy is more difficult to view and several
> nonstellar knots
> and a couple of very faint superimposed stars are more prominent. The
> brightest HII region is N4401, located 2' SE of the core,
> ~25" in size, with
> a second smaller 15" knot (N4400) close south. The core of
> the galaxy appears
> as an ill-defined low surface brightness glow, larger than
> the individual HII
> knots. A mag 14.5 star is superimposed NE of the core. On
> the SW side of the
> core is a third difficult knot, about 15" in diameter (N4399)
> requiring
> averted vision to confirm.
>
> By the way, I recently submitted an article to Sky & Tel on
> the problems of
> NGC identifications and the craft of catalogue sleuthing -
> should be coming
> up later this year.
>
> Steve Gottlieb
>
>
>