Sunday, November 6, 2011

Latest objects observed from the airstrip

Before heading off to the Deep South Regional Stargaze at the end of October this year, I loaded the 15-inch into my car and drove to the usual observing site the local club uses at the airstrip. Once there I began looking for a list of objects I found in my star atlas and planetarium software, and as soon as it became dark they began to turn up one after the other in the eyepiece. Sky conditions started off as excellent, and the Milky Way was plainly visible overhead with the dark rift from Cygnus to Sagittarius evident. As the night wore on they declined somewhat, until the impending moonrise and heavy dewing arrived and it became too moonlit and damp to be worth staying any longer.
I first located the large and bright open cluster NGC-1342 in Perseus from my heavily light polluted front yard, where it showed itself to be an impressive open cluster. From the airstrip it was even more so, with stars grouped into patches with an apparent void that divides it in two. A nice winter star cluster that rivals others in the area such as NGC-1664, NGC-1528 and NGC-1545 in neighboring Auriga in size, richness and brightness.
In contrast to the sprawling and splashy NGC-1342, NGC-7044 in Cygnus the swan is a much less conspicuous object. Both immerse deep in the star clouds and interstellar dust that pervades Cygnus, it is also very remote and thus faint. This small open cluster is visible as a dim patch of light  peppered with very faint stars. Completely out of reach from my home, it is quite small and faint through the 15-inch.
In the constellation Cepheus the king I came across NGC-7139, a fairly large and very faint planetary nebula. Nearly invisible without an oxygen III nebula filter, it became plainly visible with the filter in place. This round planetary nebula was nearly featureless except for a slight brightening around the rim. I was unable to find the central star with or without the filter, and with an integrated magnitude dimmer than 13th magnitude NGC-7139 is impossible for small telescopes.
In Cygnus I turned the telescope on the proto-planetary nebula PK80-6.1, also known as "The Egg Nebula." Imaged by the Hubble space telescope, this nebula shows it's successive shells of gas and dust, which are nestled within each other much like a Russian matryoshka doll. The nebula which shines by relfected light from the central star instead of flouresecence as true planetary nebulae do also has peculiar beams of light emerging from it in the shape of an "X." When first found in photographic surveys, it was dubbed the Egg Nebula in reference to it's shape. I was not able to make out the X shaped beams or jets, but I was able to make out the two illuminated lobes, which were white in color and looked much like the jet spat out of a plasma-cutting torch. Small and bright, this object is quite detailed at 425X. The challenge this object posed for me was not seeing, but finding it. The Egg Nebula is very small, and yet even a good small telescope at 200X and above will reveal it.
In the constellation Triangulum most stargazers concentrate on M-33, the Triangulum galaxy and it's features such as it's reverse S-shaped spiral arms and it's star forming regions. However, other background galaxies do exist there which are much more distant than M-33, but still visible in amateur telescopes. One such galaxy is the nearly round elliptical galaxy NGC-777. This 11th magnitude object is small but quite bright, and thus observable even when skies are somewhat light polluted. Only a central brightening was noticeable, in all other respects like most E2 elliptical galaxies NGC-777 is what amounts to a huge and featureless globular star cluster of old yellow and red stars.
NGC-7419 in Cepheus is another faint open cluster next to a pair of bright field stars. It's very faint with the stars being arranged in an ellipse with one of the bright field stars at one end which almost hides it. It took boosting the magnification to 298X to clearly distinguish the star cluster from the numberless field stars visible at the same time.
The galaxies NGC-1160 and 1161 I located with the 15-inch, with NGC-1160 being the fainter of the two. Previously that galaxy eluded me while searching for it with the 10-inch, whereas NGC-1161 was quickly located. Both are oval shaped galaxies but NGC-1161 is an SO lenticular galaxy while NGC-1160 is a Sc spiral galaxy. Both are canted to each other in the field of view. This is a nice duo of galaxies for those who have a medium or large aperture telescope and access to at least a reasonably dark site.
NGC-7429 is another open cluster in Cepheus, but brighter, larger and more conspicuous than NGC-7419. One group of stars forms the outline of a teardrop with the rest of the members scattered across the vicinity. A quite attractive open cluster for larger telescopes. Other objects I observed included the spiral galaxies M-31 and M-33, which showed their spiral arms, dust lanes, star formation regions and star clouds and in the case of M-31 it's star like nucleus. The Veil Nebula actually resembled a bridal veil drifting among the stars, while the Crescent Nebula or NGC-6888 showed it's full oval outline around the Wolf-Rayet star that expelled it into space along with the brighter arcs along one side. The face on spiral galaxy M-74 and the edge on galaxy NGC-891 in Andromeda were beautiful sights as well, with the dust lane along NGC-891's length apparent at 227X. Before I started to disassemble the telescope and load it into my car for the trip home, I spent a few minutes scanning the Orion Nebula, which showed details rivaling those seen in photographs, Dark clouds were everywhere among the brightly glowing ionized gasses that dominate M-42. It was a very nice night of observing and when I was not peering through the telescope, looking up at the stars.

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