by Bob Jardine
It was a Wednesday night, one day after a new moon. Perfect for the Wednesday night tradition at Montebello -- that is, except for the weather. It sucked, to be precise. However, the next night promised a few hours clear, with the CSCs calling for clouds to roll in before midnight. But it looked like the best shot we would get. There were quite a few scopes -- many of the MB regulars were there. A fun time was had by all, and the skies were quite decent while they lasted. The seeing was quite good; several of us were able to split sub-arcsecond doubles.
I took TOBY, as I usually do to MB. 10” f/6 CPT.
First, I started out on the Moon (2 days old). There was quite significant libration, as I could easily see all of Humboldtianum -- what a cool feature! Also, there were good views of Gauss, Berosus, and Hahn. I got lost after that, but probably saw Seneca & Plutarch. But the seeing was getting really sloppy as the moon set, so I soon gave up.
Fortunately the seeing was fine elsewhere.
| Struve 162 | dbl, Perseus. Peter McKone and I had split this one a week before, but I had estimated the PA at about 160, thinking it was certainly less than 180. But Peter later checked it and the reference (WDS, I think) says it is 202. So we decided to recheck. Sure enough, tonight it looked like a PA of 190 to 200 to me. Peter agreed. No, the orbit does not change the PA in a week! We both agreed that we must have suffered the same optical illusion the first time. Tonight, we centered the pair and then waited for them to drift off. If the primary drifted out of the field first, it would be less than 180; if the secondary went first, it would be greater than 180. The secondary went first. |
|---|---|
| Struve 2 | dbl, Cepheus -- clean split at both 219x and 307x. This puppy is 0.8 arcsecs. The seeing was plenty good to the North. At 307x, TOBY was yielding nice, tiny star images, with just a single thin diffraction ring. |
| Theta Aurigae | suspected a split, but it was not very clean and difficult to observe -- straight up in Dobson’s hole. At first, I thought I must have knocked the scope out of collimation; it was that bad. But I guess it was just temporarily bad seeing. Decided to go elsewhere in the sky. |
| Iota Cnc | nice, easy, wide, colorful. This is an old favorite. I stopped by on the way to... |
| Struve 1291 | near Iota Cnc. Very even magnitudes, quite close, but not too hard. Ref says 1.5 arcsecs. |
| 14 Orionis | very nice, very close, even match. At first, Peter claimed this should be 0.6 arcsecs, but later admitted that he had misread the listing in the dark and got the separation of the adjacent entry. It is really between 0.8 and 0.9. In any case, a nice clean split of a close one. I estimated PA at about 290. |
| Theta Aurigae | back to this one, now that it had moved out of the hole. Now a nice, clean split, pretty close, and a very dim companion. I guessed PA at about 300. |
| Burnham 1053 | another double suggested by Peter. Just west of Theta Aurigae. Pretty close, about 2 mags difference, estimated PA at zero -- due North. Peter said separation is 1.8 arcsec. |
It clouded up around 10:00 PM. Short night, but sweet.
Posted on sf-bay-tac Feb 16, 2005 22:10:56 PT
Converted by report.pm 1.2 Feb 16, 2005 22:17:21 PT