Blog Thursday May 16th 2013
With the summer solstice fast approaching and darkness getting more and more scarce at 52 deg north it is time to adopt my summer observing program, namely early to bed up around midnight for a couple of hours observing and then back to bed, back up at 6am for work.
When I arose at 00.15am local time, it was partially clear; I made my tea, turning this into a ‘brew & slew’ session. Once into the observatory I consulted the Kanipe & Webb Arp atlas for a target, deciding to keep low I picked Arp 254 down in Libra. A slewed the scope and centred and synchronised on Saturn. I sat there watching it on the monitor for 15 minutes or so as cloud dimmed it right down, eventually the cloud from the west passed and I bright star hopped to my target, centring on a mag 10 star close to the 3 galaxies marked. I sketched the star field and let the video run a refresh, building up the galaxies bit by bit adding detail when ‘extra’ showed on those clearer frames, rather as I would when planetary or lunar sketching when moments of steady seeing let you grab that extra detail.
An interesting thing happened whilst I was intently focussed on the Arp on the monitor of the course of 1-1.5 hrs of study no less than 5 steady satellites passed W-E through the 11’ field, taking around 45 secs to pass all the way across, all were within 5’ north or south of 105 Librae, this was a first to me, how unusual in the wider scheme of observing I have no idea?
Here is the sketch:
The northern most galaxy showing arm structure in my sketch is NGC 5917, mag 14.5, directly south and to the east of mag 9.96 star 105 Librae and extending N-S is MGC-1-39-3, aka PGC 54817 at mag 14.7, large professional scopes show the upper arm extending up to NGC 5917 forming a bridge. The tiny galaxy to the eastern edge of the fov is unknown at the time of posting.
With the sketch completed, I stood out in the observatory letting my eyes become fully dark adapted, the Sky Quality meter reading showed a steady 20.75 across the sky, which these days I would say is a good reading for my location. With the Key Stone asterism of Hercules high over head, I used the southern wall to shield the brighter southern horizon and I stared up trying to catch M13 naked eye, just on 2 occasions with averted vision I felt I got a quick flash of it, fun to try and pleasing just to get what I must note as a possible sighting. With Cygnus well up to the east, the Milky Way looked wonderful flowing southwards.
And so to bed, just past 2am local time. Dale