Saturday 6 April 2013

Leo Galaxy Hunt

     Shhh.  Be vewy vewy quiet.  I'm hunting gawaxies. Hehhehehehehe.

     The hunt is on, and my success rate is impressive, if a bit behind schedule.  Normally, my object list to-do pages are set up so as to take a full night's session per page (about a dozen or so objects over about three hours).  However, I have been on my 1st page of Leo for several nights now.  That's okay, as I am not hurrying through the universe, but taking my time and getting to know an obscure corner of the constellation.  10 NGC galaxies are listed on the first page of my goals for southeast Leo (32 pages in all for the constellation!).  Nearby stars include 2, 3, 5 and 6 Leo.  Five galaxies were observed on previous good nights without much trouble.  Three of the fainter ones fell victim to my 12" mirror last night, and now only two remain.

     I have enjoyed 4 nights in a row of clear skies in Essex County, Ontario, Canada, an almost unprecedented event, especially this time of year.  Because I have moved the scope to a site south of my nearest city, nearly up against Lake Erie, the skies are dark to the south, east, and overhead, thus making Leo a perfect area for observing.  However, Monoceros is hanging in there for some final observing early in the evening, allowing me to capture a few NGC clusters before heading into galaxy land (I can recommend oc 2253 for almost any aperture).  I am still involved with star clusters that surround 2244 and the Rosette Nebula.  This is one of the richest areas for sweeping into incredible star fields that the sky has to offer.

     In my 4 nights in a row of April observing, I have managed to log 14 new NGC objects!  I've also seen other non-NGC objects, mostly clusters in Monoceros, as well as several double stars and variables in both constellations.  While now convinced that my scope can find and resolve virtually any open star cluster listed in Uranometria, finding some of those fainter Leo galaxies has proven to be a more difficult project.  The last four nights have taught me much.  I still believe that I can find every single NGC galaxy in Leo, but I now realize how difficult and lengthy such a project will be, and how little of the faintest galaxies there is to see (basically the shape).  Still, it is fun hunting them down, and extremely rewarding when another one is captured in all of its faint, averted vision glory.  I could never locate them all from my back deck, which is much too suburban a location.  But just 12 minutes drive south of here, past the town where I live, is a whole new sky, much darker and friendlier to galaxy hunters.  We require the darkest skies possible.  And sometimes even that isn't enough.  Low humidity is also required.

     Some of the galaxies I found last night were among the faintest objects of the entire NGC catalogue.  Luckily I had an astronomer/friend with me to confirm sighting of one of the rarest for a 12".  NGC 2873 has the following specs:  0'.8 X  0'.2---visual mag. 15.4; surface brightness 13.1.  This is not a galaxy for the faint of heart, or for those quitters who don't see it on the first try.  What makes it worthwhile is that it is nestled between two other galaxies, and found immediately north of them.  2872 is pretty bright for a 12" scope, and probably even visible with a 10" under good skies.  Virtually touching it is 2874, though in the 12" at moderate power (150x) there is a tiny amount of black sky in between them.  This galaxy is much fainter, though significantly larger and very elongated.  With averted vision its dimensions go scooting quite far south and a bit north.  Then comes 2873.  Because of its tiny size, its surface brightness is just enough to make it visible to patient viewers with 12" scopes using averted vision (in a good sky).  It appeared to me, however briefly and faintly, as a small oval between the two bigger galaxies, but just to the north, and just south of a threshold star.  All three NGC objects fit easily into the 150x field of view.

     After seeing three faint galaxies in the same high power field, it was refreshing to view the Leo Triplet again, just barely fitting into my 25 mm eyepiece at 60x.  Sunglasses are now almost required by comparison.  This is another area of good galaxy hunting, but for now I just come to look in awe.

     I still have two faint galaxies to locate to conclude my first page of Leo.  I had predicted that my study of the entire constellation would require about 32 nights to cover the 32 pages of planned objects.  But I have now spent parts of five nights just on the first page!  So I have learned a lot about my scope and my skies, and will readjust my expectations accordingly.  With 85% success rate so far in Leo (and about 98% in Monoceros), I will continue my search for Leo galaxies and the darkest skies possible.  Please let me know if you are in the area of Leo or Monoceros (or Essex County, Canada), and how you are doing.
Mapman Mike

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