Getting into Ursa Minor

by Jamie Dillon

Last Sunday, 3 August, my ole buddy Jim Everitt and I headed up to the Peak for some 1st Q observing. Once again, there was no sign of another human after dark up there. Lots of peepers and crickets and owls. Sky had a 6.2 limiting magnitude, and seeing was good, 4/5.

The moon was too tempting, setting over the Bay. Studied a sharp circular little crater in Serenity which'll be familiar to you Gidney and Floyd types. It was Bessel, a treat on my end as Friedrich Bessel is one of my favorite characters in the history of science, the guy who figured out how to measure stellar distances, got the parallax to 61 Cygni. Was described by his contemporaries as a really engaging person. A long rille heading south from Bessel stood out clearly.

As the Moon got serious about setting, Everitt and I played the ID game. Put something in the eyepiece and challenge the other guy to identify it. Hadn't done that in a while, noncompetitive fun. Jim put in 7331, fancy galaxy in Pegasus, and M52 the showpiece OC in Cassiopeia. I threw in 5907, killer edge-on in Draco, and 6939 and 6946, a big pretty OC in the same broad field as a huge face-on galaxy. We studied 6946, amazing esp in Jim's 15, big arms, galaxy keeps getting bigger the more you watch.

Once the sky was good and dark I went back to collecting galaxies in Draco. Had one warning object (a term Albert, Bob Cz and I started using a couple of years ago, not sure who started it, for a nutbusting object), 6140. I finally asked for help; it's been a good long while since I gave up on an object plotted in SkyAtlas and I wasn't about to. From the view in the 15 I could go back to Felix and see a dim splotch at 126x. Surface brightness for the thing is 14.8, so I didn't feel too desolate. It's slightly misplotted both on SkyAtlas and in UM2000, about 40' too far east, an uncommon occurrence. (Felix is a Celestron 11" f/4.5 Dobs with optics made by Discovery Telescopes. Was using a 22 Pan, 16mm UO Koenig, 10mm and 6mm Radians.)

Then into Ursa Minor. NGC 6217 is my first DSO in UMi. Hey, like someone said, it's a big sky. Pretty galaxy. Triangular shape with base to the West. Very bright stellar core. 6068 is in the same area, with a bright triangular rag of a halo.

Yes Mars was spectacular. Everitt sketched it, and looking at his sketch I held my tongue at first because the dark central area looked just like a dog biscuit. Sure enough that's what was in the eyepiece. Syrtis Major and Mare Tyrrhenum, collectively known as the Dog Biscuit.

After Everitt rolled, I went back and studied 6503, big find from the week before, all those swirls and lanes. Stopped and looked for the first time at rho Cas, right near that wonderful cluster 7789. It had been featured in the July S&T, and James Kaler goes on and on about it in Extreme Stars. It's a supergiant in whom the orbit of Mars would fit, near the limit of how bright a star can get without blowing itself apart. Going thru all kinds of shenanigans and keeping the variable star experts busy.

Another fun night in paradise.