Off the Beaten Path with Steve Gottlieb:
Deep Sky Challenges for Early Winter

Pease 1 = PK 65-27.1
21 29 59.4 +12 10 26

Pease 1 is one of only four known PNe located within a globular cluster -- the others are GJJC-1 and two recently discovered planetaries in NGC 6441 and Palomar 6. Of the four, Pease 1 is the brightest and the only reasonable visual target, although GJJC-1 has been detected in a 25-inch. A good finder chart is a necessity, though, to track down Pease 1 as the planetary is situated is just 25" from the center of M15!

Image by Stan Moore. Three filtered exposures
were combined to emphasize the nebula.

At 380x (using an equatorial platform) along with the finder chart it was not too difficult identifying a quartet consisting of two easy pairs of mag 14 stars located 1.5' NW of the center of M15. Getting a feel for the scale in the eyepiece compared to the finder chart, I next identified a 30" string of three or four mag 14.5 stars ~50" NE of the center. Pease 1 is situated midway between this string and the center of the nucleus. At 500x, the precise location was pinned down within a small unresolved clump of stars just at the edge of the nucleus 25" NE of center. The PN was apparently buried with this small clump. Blinking with a UHC filter (which dramatically dimmed the cluster), revealed a definite brightening at the NE edge of this clump. With extended viewing this brightening sharpened to a stellar point several times, particularly with the filter attached. It took 20- 30 minutes to identify the field and lock onto the position of Pease 1 but other observers have reported spending up to two hours tackling this object, so you can see the advantage of using a tracking platform or mount.

Pegasus Dwarf Galaxy = UGC 12613
23 28 34.1 +14 44 48

This is one of the low surface brightness dwarf members of the Local Group. It was initially not seen at 220x. At 100x a very low surface brightness hazy region with no concentration was visible just following a trio of mag 12 stars. It was very difficult to estimate the dimensions or orientation as the halo gradually faded into background but possibly 4'x2', extended WNW-ESE. I also took a look at 140x, although no other details were seen. By the way, I would have passed right over this object without a finder chart and use of low power!

Hickson 1 ( HCG 1) = UGC 248
00 26 07.1 +25 43 30

The first entry in Hickson's list of compact groups is a challenging introduction to this class of objects. This group contains an interacting pair of galaxies (HCG 1A and 1B) but at 220x I logged a single faint, fairly small glow, ~40"x20". At 280x, though, the cores of "A" and "B" were possibly resolved at moments. A distinctive asterism of four stars is superimposed on the group. The "C" component (V = 15.6) was barely visible 2.8' due west.

Maffei I = Sh 2-191 = UGCA 34
02 36 35.5 +59 39 18

Originally listed as a nebula by Sharpless, this heavily reddened object was found to be a galaxy in 1967 by Paolo Maffei on a near infrared photograph. At a distance of roughly 12 million light years it is a close neighbor to our Local Group but buried behind dust within the Milky Way. Maffei I is a difficult object visually due to the richness of the surrounding milky way star field. In fact, a group of faint stars (Czernic 11) is superimposed on the galaxy. In my 13-inch the core of Maffei I appears as diffuse haze elongated east-west near the NW edge of a small trapezoid of stars.

The Fornax Four (Globulars)
02 39 49 -34 15.5 (NGC 1049)

The Fornax Dwarf Galaxy (MCG-6-7-1) is an extremely low surface brightness target but it contains four relatively high surface brightness globulars which you should be able to ferret out even if the galaxy is not visible. The brightest, NGC 1049, was discovered by John Herschel at the Cape of Good Hope and described as "like a star 12th magnitude a very little rubbed out at the edges, a curious little object and easily mistaken for a star, which, however, it certainly is not."

The next two brightest globulars, Hodge 4 and 5 (discovered photographically by Paul Hodge) appear in my 17.5" as a fairly faint, round glows (perhaps 30" in diameter) with brighter cores. Hodge 4 can be found 7' ESE of a mag 8 star embedded in the west side of galaxy. Hodge 2 was the faintest of four viewed and appeared as a small, low surface brightness glow without central concentration. A pretty double star to the NNW is collinear with the globular.

Abell 4 = PK 144-15.1
02 45 24 +42 33.1

This planetary is one of the smaller objects discovered by George Abell using the Palomar Sky Survey in the mid 1960's. What I find particularly interesting is the location -- just 40' ESE of the center of the large open cluster M34! Based on its proximity, you might think this planetary would be better known, but it is a very difficult unfiltered so you can see how the great visual observers of the past could easily have overlooked this object.

I reobserved this planetary recently with my 17.5" and picked it up at 100x using the OIII filter as a very faint, round, 20" disc forming the NW vertex of an obtuse triangle with mag 8.7 SAO 38305 3' SE and a mag 10.5 star 1.6' SE. The best view, though, was at 220x-280x using a UHC filter. At these powers it was visible steadily with averted vision as a crisp-edged disc of low even surface brightness. Knowing the location I could remove the filter and glimpse the planetary but would have passed over Abell 4 otherwise. You may also find a galaxy, CGCG 539-91, plotted next to Abell 4 but this was simply a case of misclassification and it refers to the planetary.

Hind's Variable Nebula = NGC 1555 = Sh 2-238
04 21 56.8 +19 32 04

Hind's Variable Nebula (NGC 1555) was discovered October 12, 1852 surrounding the young variable star T Tauri (mag 9-13). This object, as well as another piece discovered by Struve (NGC 1554) created quite an excitement in the later part of the 19th century as observers and photographs revealed a variability to the nebulosity. Dr. Harold Corwin describes the complex as consisting of "reflection nebulae, created as thick dust clouds near the star move about, mostly casting shadows, but occasionally letting "shafts of sunlight" out to illuminate the surrounding dense interstellar gas and dust."

Apparently this was an easier object to view in the mid 1800's as it is currently a very tough visual target. At 100x and 140x (unfiltered) an extremely faint haze was highly suspected on the W or WSW side of mag 9 T Tauri in the direction of a mag 14 star to the west or slightly south). The hint of nebulosity did not appear as an arc (as on photographs) but a sketch made at 100x matches precisely the orientation of the nebulosity with respect to T Tauri. I lost the nebulosity increasing the power to 220x. Jay Freeman recently observed this nebulosity in a C-14 from the Sierra foothills and reports "It was very faint, but at 98x I could suspect a patch of nebulosity an arc-minute or so west of the star, and had a more solid view of it with an Orion UltraBlock filter."

In 1868 Struve also reported nebulosity around the 14th magnitude star (verified by another great visual observer d'Arrest) but observations a decade later and current photographs show nothing at this position. NGC 1554 is known as Struve's "Lost Nebula".