Sunday, May 29, 2011

Hygeia verified

After a week of rain, lightning, and clouds of doom, we finally had a clear day today. Tonight was perfect with temp in the 70's, cloudless, moonless, and enough wind to keep the bugs away. It was a bit gusty at times but not bad. Saturn was particularly clear and well out of Leo now. I could clearly see Titan and Rhea and was so flabbergasted to see ANY moon of Saturn I didn't notice little Dione on the other side of Saturn. I'm not sure why I've never noticed Titan before except that perhaps it has always been hidden by Saturn's glare. It was very noticeable with my 10x ep. The goal of tonight though was to verify that I really did see Hygeia last Sunday. I looked at my former position and sure enough there was a missing 'star'. It was a bit harder to find this time since the power was off and CdC wasn't available. I used the finder in S&T and noticed that there seemed to be an extra 9th magnitude 'star' in the field near N28, a bright double between Alpha and Sigma Libra. It seemed to form an isosceles triangle with SAO183113 and SAO183119 with the former being the other base and the latter being the apex. CdC put it's position a bit further west but the orbital elements are a bit old.

Sunday, May 22, 2011

Hygiea in Libra

Hygiea is a big black carbonaceous asteroid, currently in Libra. It's the fourth largest but has a very low albedo of 7% which means it only reflects 7 percent of the light from the sun. It currently in a favorable opposition and is about mag 9.2. I found it (I think) with my 8" dob just about 3° north of Sig Lib. At least there was a 9.2 mag object that shouldn't be near HR5620 according to CdC. If that is the case, Hygiea is a bit east of the position predicted by CdC, which is not unusual. In order to verify it, I'll have to take another look next time the sky is clear to see if anything has moved. That may take awhile. I think we've only had two clear nights this year! Today was a rare sunny day and we drove to St. Louis for some C1, C2 action with Daryl Lipscomb. Zigzags had 2 squares of C2 and three of C1 and Daryl called a fine dance.

Monday, May 9, 2011

Some ETX doubles in UMa

I can't believe it's been several months since my last observing session! Actually I've been out a couple of times since returning to Rolla in April. Once with the 8" dob to check out Saturn that is nice and high in the evening now, another time earlier this week to check out the four planets at dawn (I only saw two, Jupiter and Venus peeking through the murk before sunup), and once with my ETX70, only to find that the trip up from TX managed to break my focus knob 'fix' loose. I had to use some epoxy to re-glue the washer I used to patch the broken plastic. It worked nicely tonight and I re-acquainted myself with the procedure for entering custom objects. I selected a few binocular doubles from May's S&T. There was an almost half moon, clear, and about 78F, dry with no dew, and a bit windy. The moon cast enough light that the dimmer stars were washed out but I was able to see Polaris easily. I even managed to spot a dim 7.6 mag star between Mizar and its companion Alcor in UMa. A bright satellite passed by Mizar about 10:00pm. It was the first of three that were to pass through my FOV tonight. It's always nice to spot a satellite this way. D1 or Gamma and 11 UMi were the first stop after alignment. I thought they looked a lot like Mizar and Alcor. Next on my list was TT and 8 UMi. These are mag 6.8 stars that were barely visible in my 7x50's but clear in the ETX. I found this pair by GOTO Kocab. The pair I called D2 (lambda and 2 Draconis) looked blue and orange to me. The group I called D3 was a nice string of four stars that I thought all looked blue-white. The 'crouton' in UMa was too large for the ETX but I saw it easily in 7x50's. All in all, it was a pretty successful night.