Sunday, May 4, 2003

If Not For Dew...

I had my 10" f/5.7 CPT Dob out back tonight. First clear night in a long time. Sure looked good, but even early on it was obvious that things could get wet.

Before going out I went to the limiting magnitude page at:

and filled it in for 9:30 p.m.

It returned the familiar triangle of Alpha and Gamma Bootis, and Alpha Coronae Borealis, along with Alpha Canum Venaticorum, Epsilon and Eta Ursa Maoris, and a third triangle (?) of Alpha, Beta, Gamma and Delta Leonis.

I waited a while and looked at M3, which was very pleasing at 72X and 121X. It broke up nicely at the higher power.

I then looked in the NSOG for targets in the triangle areas, and decided to work Leo since it was furthest west.

NGC 2903 was very good at 72X, easy to find. At 121X it was elongated with a bright core. At 207X the stellar core was popping out and there was an halo surrounding it that seemed slightly offset to the east. The elongation of the arms was to the north and south.

Unfortunately, this would be my only success for the night. I tried for NGC 2916, but only found the nice double star 6 Leonis, shining blue and gold.

I hunted for a few other targets through a dewed Telrad, and when I found my 9x60 finder useless, I called it a night.

As amazing as it sounds, I had counts of 38, 16 and 31 stars, respectively in the triangles. This is from my Los Gatos backyard. According to the calculator on the above referenced page, that give 6.83, 6.80 and 7.02.

Next time I'll chart the star positions to confirm. There were many stars that appeared repeatedly with averted vision.

If not for dew, it could have been a great night out back.

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