My first Andromeda globular cluster December 15, 2006Posted by dorigo in astronomy, internet, personal, science.
Yesterday the weather promised to be stable and clear throughout the Alps. The moon being close to new would not disturb deep-sky observations, and in addition a tail of the Geminid meteor shower (which peaked yesterday at 8AM UT) would cheer up any stargazer. So I organized an outing with Mauro and Mirko, at the rifugio Dolada, over the Santa Croce lake.
The preparations were complicated by the fact that I had most of my equipment at home, four flights of stairs plus 800 meters from my car. 30 lbs for the mirror alone, plus another 20 for the eyepiece case, 20 more for the truss tubes and hardware, and maybe 10 more for the upper cell. In addition, I had to bring a bag with my computer and some other stuff, plus warm clothing for the chill of the alpine night. A total of about 100 pounds of stuff. I did in two rounds, and as at 7PM I drove away to pick up Mauro, soon getting into the friday evening traffic jam of Marghera, I found asking myself whether the whole thing was worth the stress.
It usually is… Although this time trouble was not over yet. It took me 45 minutes to get to Mauro’s place (usually it takes 20), plus some other 70′ to get to the observing site. And once there, we had such trouble in getting the instrument decently aligned that I framed M42 inside my Tele Vue Panoptic 27mm eyepiece only at about 10PM.
From there on, however, we had only fun. Nice views of many interesting objects. We spent quite some time on easy targets as M33 and M82, when the former allowed us to see at least eight condensations (one of which I had never noticed before) and very bright and extended spiral arms, while the second was glorious and complex, with the black interruption in the disk plus many subtler features. We made several comparisons between the views from my 16″ dobson and the 12″ lightbridge brought by Mirko, and concluded that the latter is a real deal for the 1000$ it costs. Views were always brighter in my instrument, but only slightly so.
Mirko, who can locate almost anything in the night sky – including any Hicksons, Abells, NGCs, you name them- framed G1 for me at a point, and it was a pleasant view. G1 is the brightest globular cluster in the Andromeda galaxy M31. It stood faint at Mv=13.7, but clearly non-stellar, at the apex of a triangulum with two 13-th magnitude stars (see picture on the left). Nothing exceptional from the looks of it, but if you think of what you’re looking at -a stellar system within another galaxy- things change perspective a bit, at least if you’re an amateur astronomer.
Of course, many other globulars in M31 were at reach of our instruments -at least 20, according to the list you can find in http://www.cloudynights.com/item.php?item_id=1559 . However, I found one was enough… I usually prefer to spend more observing time on the intricacies of M42 or M33 or some other bright object, or to look for clusters of small galaxies.
Just half an hour into midnight, we started packing. The night was cold, and we all had business to attend to the next morning… Admittedly, these outings are only possible every couple of months or so, such that by then one manages to forget how tough it is to pack and bring the stuff to the car, drive, mount, take apart, drive back, etcetera… I wish the sky in Venice was less polluted!