Thursday, May 22, 2014

Spring Scrimage

More than three weeks ago I attended the "Spring Scrimmage" held at the site where the Deep South Regional Stargaze is held every fall. There I stayed for two days and two nights observing mostly galaxies and the planets with the 15-inch Dob and a few other folks' telescopes too. The weather was quite good Friday night and steadily worsened the following night until it was no longer worth observing. While I looked at a number of favorite objects, I looked for some unfamiliar objects and made these sketches Friday night. I also made use of newly acquired astronomical software and a laptop to locate and observe the comet C/2012K1PANSTARRS. During the day I updated my logs and toured the area surrounding the Feliciana Retreat Center.
 
 
One object I sought out was a trio of galaxies on the Virgo-Coma Berenices border. Comprised of three edge-on spiral galaxies canted at angles to one another, all fit comfortably in the 18mm Explore Scientific 82 degree eyepiece at 111X. The brightest member is the tenth magnitude system NGC-4216, which seemed to show a hint of its dust lanes and a very bright inner core. It spans more than eight arc-minutes and is some 40 million light years away. The next brightest galaxy is NGC-4206, fainter and smaller it was still quite easy to spot. I noted a central brightening and a similar appearance to NGC-4216, which shines at magnitude 12.5. NGC-4222 is even fainter and required some effort to pull out of the sky glow. This Sd spiral galaxy shines at magnitude 13.5 and has an apparent length of 3.5 arc-minutes.
While the Virgo Cluster is the largest concentration of galaxies visible to amateur telescopes, there's many more visible in lesser known constellations such as Lynx. Turning the 15-inch to the Lynx galaxy NGC-2832, I was surprised to find three others in the field of view at 227X. The brightest is the E4 elliptical galaxy NGC-2832, which shines at magnitude 11.5. Overlapping it is another much fainter and very tiny galaxy, NGC-2831. Appearing as a brightening in the halo of the larger galaxy, this minuscule object shines at magnitude 13.4 and is less than a arc-minute across. Next to NGC-2832 and 2831 is another much fainter edge-on system is also present, but 15th magnitude NGC-2830 eluded me. Two more galaxies, NGC-2829 and IC-2460 shine at magnitude 15 in the same field of view. Both are very faint, elongated fuzzy spots less than an arc-minute long with brighter centers. I suspect the view of these galaxies would be far better from a very dark site, I was not quite able to tell if IC-2460 was elongated or round and which was it was pointed.
Right now we have another PANSTARRS comet in view, but unlike the comet of last year this one is conveniently located for evening observation among the stars of Ursa Major. At about eight magnitude it's easy for the 15-inch, folks were having no problem seeing it with small telescopes. At present comet C/2012K1PANSTARRS is both high in the evening sky and well away from the Sun. It will remain well placed for observation until late June. After remaining near the Sun for over two months, it will again be well positioned for observation in the predawn skies.
Lynx has numerous galaxies, but only one that could be honestly called a bright galaxy. NGC-2403 is similar to M-33 in Triangulum, a face on Sc spiral galaxy 12 million light years away. It's extends across 18 X 11 arc-minutes of sky and shines at magnitude 8.4. Frequently mistaken for a comet, this galaxy showed hints of the spiral arms and it's brightest star forming region. Nearly 1,000 light years across that H-II region has its own NGC-designation, NGC-2404 and is comparable to the Tarantula Nebula in the Large Magellanic Cloud. The galaxy would be far more impressive had the skies been clearer and darker, but I was lucky to get the one good night I got during the Spring Scrimmage.
In Lynx I came across the pair of galaxies NGC-2798 and NGC 2799 while looking through a list of objects of interest within that constellation. NGC-2798 has an apparent magnitude of 12.3 and an apparent size of 2.8 arc-minutes. NGC-2799 shines at magnitude 14 and is 2 arc-minutes in length. Together they form the pair of peculiar galaxies, Arp 283. Both galaxies are tugging on each other hard, evident in their distorted and disturbed structure. NGC-2798 and 2799 are Sba and Sbm type galaxies respectively, and both had a quite high surface brightness. I did not see any sign of their tug of war at 227X, but this is a promising object to return to at a darker site.
 
Other objects I observed were Mars, Jupiter and Saturn, and scores of other galaxies. I looked at a number of Virgo, Coma Berenices and Canes Venatici galaxies, along with others in Hydra, Draco and Hercules. I also observed a few Ursa Major galaxies including M-82, whose supernova is still visible. It was a very nice night on Friday, but the weather was poor Saturday and I took the telescope down by 10 p.m. Nevertheless, I got some amazing views of the planets, Syrtis Major and the polar caps on Mars were very clearly visible. Jupiter showed eddies along it's belts, and Saturn's rings showed both the Cassini and Encke divisions. I am planning to attend the Spring Scrimmage again next year to sketch more spring galaxies, weather permitting.