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Type: bright nebula (HII region)
Mag: B=?, V=?
On July 16-17 and again on July 17-18, 1999, I had my Celestron 14, Harvey, at Fremont Peak. We had quite good transparency both nights, and on Saturday the 17-18th, the fog was in on the coastal plain below the peak, so that after moon set it got pretty dark.
Part of my program for those two nights was chasing after some of the Sharpless objects that Jim Shields recently listed on his web site. While I was hunting the listed objects, I took an occasional moment to look at other similar objects near them, as I happened to find them in the pages of _Millennium_Star_Atlas_. Here are my notes, more or less in the order of observation.
July 16-17: Observing after moon set, with a Celestron 14, at 98x (Vernonscope 40 mm Erfle eyepiece), with an Orion UltraBlock filter installed ahead of the eyepiece.
Sh 2-1: See Sh 2-1 as shown on _Millennium_Star_Atlas_, notably excepting its northernmost extension. This nebula is brightest in the two degree extension west of 2 and 3 Sco.
IC 4706: ... is easy.
Sh 2-44: See as a 30' bright patch with some structure, centrally located on its cataloged position.
Sh 2-37 (which seems to be the same as IC 1283/4): ... is easy.
Sh 2-35: Sh 2-35 is harder, but seen when I move the telescope. Sh 2-53: See Sh 2-53.
July 17-18: As for the preceding night, except that I did *not* install the UltraBlock. I was lazy. I didn't make as many notes about appearance that evening, either. However, I logged Sh 2-82, 2-84, 2-88, and 2-90 as seen, and also noted that I saw Sh 2-71, with a central star.
I had the impression that most of the larger Sharpless objects are not so much hard to see as hard to notice -- I am simply not in the habit of looking for big, low-surface-brightness objects with little contrast. My response to finding many of them was not so much "gosh, that's hard to see," as "oh... yeah...".
On these evenings I also spent some time hunting Palomar globular clusters. On the first night, I used a Vixen 8-24 mm zoom Lanthanum eyepiece, which gives 163-489x with the C-14. Past experience with this unit has made me aware of two virtues; first, at the longest focal length, it has a wide enough field to make it easy to go from the finder to the main telescope without getting lost; second, its range of exit pupils, 2.2 down to 0.7 mm, spans pretty much the entire region I might want with globular clusters -- and I anticipated that some of the Palomar globulars might be difficult enough to require fine tweaking of the exit pupil to see well, if at all. When I located an object, I would vary the magnification while keeping the focus sharp, and make such notes as I thought appropriate.
Pal 14: Best at about 250x.
Pal 15: Visible best at 200-250x. Tough object.
Pal 7 (which seems to be IC 1276?): Granular to resolved at 163x. Pal 8: Granular to resolved at 163x through 489x -- zoomed up out of curiosity.
Pal 9 (which seems to be NGC 6717): Granular to resolved at 163x.
Pal 10: Tough, best at about 225x.
Pal 11: Granular at 250x, seen at 163x.
On July 17-18th I found one more Palomar globular, Pal 12, at 244x (16 mm Brandon), but did not make any additional notes about it.
I believe I have now seen all but two or three of the Palomar globulars -- the ambiguity is because I have a note to myself to recheck Pal 6. They seem to span a rather wide range of visibilities, from things for which a C-14 is merely loafing, to some worthy of serious whining, like Pal 15.
Perhaps the highlight of the weekend was finding the Aquarius Dwarf Galaxy, which was in my cats and dogs list, but not in mind when I took a gee-whiz look at the Saturn Nebula, and noticed the object on the same page of _Millennium_. I had 244x in use, and did not think to reduce magnification, which I might have if I had been deliberately out to find the little galaxy. Yet things worked out fine. With averted vision I found a round, diffuse glow vaguely an arc minute in diameter, at the indicated position, with a star of vaguely visual magnitude 13 south adjoining. Today I pulled an image off the Digitized Sky Survey and verified field and star; I seem to have gotten it right.
-- Jay Freeman
The Messier objects
The Bennett objects
The Caldwell list
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