Saturday, November 22, 2014

2014 Deep South Regional Stargaze

After attending the 2014 Spring Scrimmage at the same site, I drove out and spent four days and nights attending the long awaited 2014 Deep South Regional Stargaze, held annually near Norwood La.. It was well worth the effort, given that all four nights featured good if not excellent sky conditions and clouds intruded only on one night for several hours before retreating for the rest of the night. While attending the DSRSG I finally had an answer to a long standing issue with my dew heaters I was stumped trying to figure out. After a conversation with Ron Keating, who makes and sells the Dewbuster dew heater controllers, I realized I was placing the temperature probe for the secondary mirror in the wrong location. Once I corrected the problem by inserting it behind the secondary mirror, the heater worked perfectly without creating annoying heat blooms that wreck the view. And while there I logged dozens of NGC, Arp, Perek-Khoutek, Sharpless and Palomar objects I had never seen before when I wasn't looking at old standbys and favorites.
Among the first object that I observed with the 15-inch was the rapidly receding comet C/2014E2 Jacques among the stars and deep sky objects of Aquila. Much smaller and fainter than the last time I observed it more than a month before, it still showed a subtle forked tail and a brighter inner region in the center of the coma. While a shadow of what it once was, C/2014E2 Jacques was still well worth observing even though it glows at around 12th magnitude or so. Soon it will be out of reach of any amateur telescope, but others are now inbound that will take its place.
After spending time observing other deep sky objects in Sculptor I have observed in the past, including the bright galaxy NGC-253 and globular cluster NGC-288, I looked for other objects I have yet to see for the first time. One such object was the Sa spiral galaxy NGC-24, which shines at magnitude 11.5 and is some 6 arc-minutes long. As such it's surface brightness was reasonably high, which enabled it to be visible despite the sky glow from Baton Rouge some 50 miles to the south. I did see a brighter central region and it appeared a little "wooly" around the edges. That is consistent with it being a spiral galaxy, which is littered with star forming regions and star clouds along it's spiral arms.
In Aquila can be found dozens of planetary nebulae, ranging from nearly stellar disks barely resolvable at very high power to large, ghostly rings or disks. Sharpless2-71 is definitely one of Aquila's more unusual planetary nebulae, with an irregular, lopsided structure with an apparent bright central star. It is in fact a foreground object, the true central star shines very feebly at 19th magnitude. The brighter outer rim is missing on one end and the darker central void merges into the surrounding sky. This planetary nebula looks more like a faint comet than a planetary nebula, but it does respond well to an O-III filter. Sharpless2-71 eluded several attempts to locate until I succeeded at the DSRSG. It was one of the most satisfying finds I had for months.
Palomar 11 is one of 15 faint globular clusters found by Palomar observatory through a survey funded by the National Geographic Society. This globular cluster's located along the fringes of the Milky Way in eastern Aquila. It has eluded numerous efforts to find it. Until that is I brought the 15-inch to bear on it at the DSRSG, where skies are considerably darker than where I usually observe. At 227X it appeared as a round, faint glow with a slightly brighter center. I thought I glimpsed a slightly granularity around the edges, but for the most part aside from the slight central brightening, Palomar 11 was otherwise featureless. The main prize was in finding it, and efforts to find Palomar 10 and 12 failed to reveal them through the same telescope.
In Aquarius numerous galaxies await the amateur astronomer. While most are faint, there's a number of easy objects for 8 or 10-inch telescope under reasonably good skies such as the spiral galaxy NGC-7184. This 11th magnitude system has a Hubble classification of SBc and also shows evidence of a burst of star formation in a ring shaped region around the nucleus. Also in the field appear the galaxies NGC-7180, 7185 and 7188. NGC-7180 is a 12.6 magnitude SO system whereas NGC-7185 is a magnitude 12.2 elliptical system. The final galaxy, NGC-7188 is a Sb system with a magnitude of 13.2. All three are some 60 million light years away, while NGC-7184 is a far larger and more massive galaxy 40 million light years behind them.
Aquarius is well known for being home to the bright globular cluster M-2, there is another globular cluster farther away, fainter and far harder to see. NGC-7492 is a very faint and challenging object under light polluted skies, and until I looked for it at the DSRSG the only other place I seen it from was a site in the middle of the Conecuh National Forest with my 10-inch. NGC-7492 is some 8 arc-minutes across and weakly shines at 11.3. Like Palomar 11 I saw what appeared to be slight granularity around the edges, possibly because the brightest stars shine at around magnitude 15.5. This globular cluster is some 84,000 light years away and is rapidly approaching us at the velocity of some 125 miles per second.
Andromeda has many more objects for amateur astronomers beyond the Andromeda Galaxy and several other well known examples. One such object is the NGC-80 galaxy group, whose members include NGC-81, 82, 83, 85, 86, 91, 93, 94, IC 1564 and MCG+04-02-010. NGC 80 itself is a 13th magnitude, round object with a brighter core. NGC-83 is another round 13th magnitude object while the third galaxy's identification is either NGC-90 or 91. Accepting NGC-90 as the correct identification  for this galaxy,  this spiral system shines around magnitude 14. A fourth galaxy, which is most likely NGC-85 appeared at the very edge of the field at 227X. The distances of these galaxies ranges from 240 to 290 million light years away.
Arp 273 is one of more than 300 interacting and peculiar galaxies cataloged by the American astronomer Halton Arp in the 1960's. This object consists of two galaxies that grazed each other with dramatic results that are apparent in photos taken by large observatories and the Hubble Space Telescope. However these galaxies are 340 million light years away and shine barely above 14th magnitude. Both galaxies put together are 1.7 arc-minutes across, giving them a reasonable surface brightness. They appeared as a lopsided oval spot with a brighter center and a faint streak that is the intruder galaxy whose gravity severely distorted and disrupted the larger galaxy. Even at the DSRSG Arp 273 was not an easy object for me to find with the 15-inch, but finding it brought me a good deal of satisfaction.
NGC-160 is a 13th magnitude oval galaxy with a brighter core that responds well to fairly high magnifications dues to it's small apparent size of 2.2 arc-minutes. NGC-160 lies 240 million light years from Earth. It's featureless appearance is consistent with it being an lenticular galaxy or possibly a transitional S0/Sa spiral galaxy.
NGC-214 is a 13th magnitude barred spiral galaxy which at 227X appears as an elongated object with a brighter core. It's small apparent size of 1.9 arc-minutes in length is due to it being oriented between face and edge on and it lying 200 million light years away from us. Little of it's structure otherwise was visible through the 15-inch at 227X.
While attending the DSRSG I also observed dozens of other objects that were seen for the very first time in the constellations of Andromeda, Aquarius, Cygnus, Aquila, Sculptor, Pisces and Cetus. Numerous NGC, IC and Messier objects well known to me were also observed such as the Andromeda and Triangulum galaxies, The Cygnus Egg Nebula, The Veil Nebula, The Ring Nebula, and the Orion Nebula receives attention. I also showed numerous deep sky objects to passerby, including a University of South Alabama physics professor and his students when they were not looking through an 8-inch Celestron SCT he brought along. The DSRSG this year saw the best weather I experienced in years. The turn out was also very good, with over 100 people attending. I am now looking forward to the upcoming 2015 Spring Scrimmage, where I can peruse spring and summer deep sky objects.