Dino Pt. -- 1 Trilobite, 2 Comets, 4 Fleas

Bob Jardine

Yes, there was a Trilobite at Dino Point last night -- well, at least an astronomical object that looked to me like a Trilobite!

Comet 17P Holmes reminded me of this ancient life form (see http://en.wikipedia.org/wiki/Trilobite

The "front" edge of the large outer edge was a very well-defined horseshoe shape. Then it was elongated in a kind-of rectangular shape overall, and the trailing edge was very ill-defined. Just inside the front edge was a very low surface-brightness uniform glow, with a bunch of background stars showing through. Inside that was a brighter elongated shape, more like a traditional comet coma + tail, looking just like the Trilobite's central feature. This tail also petered out and merged with the outer brightness as it got towards the "rear". The overall object was huge, nearly filling the field of the 35mm Panoptic. Using f/5 12.5" Portaball. That's a 1.5 degree field.

I also checked out Comet 8P Tuttle. This one was small, but pretty bright -- and very easy to find just North of Gamma Cep. Round and fuzzy, with a brighter (but non-stellar) center. Looked a little like many a small face-on galaxy with a brighter core. (David: I tried really hard to detect spiral arms, but sadly I did not succeed.) I viewed it with the scope at 93X. I was also able to see it easily in 15X50 IS binocs (but not in 10X50 traditional binocs).

Keep your eyes on this comet, over the next month or so; it is expected to become visible with the N.E., if you know what I mean and I think you do.

After warming up on the two comets, I decided to follow Sue French's November article, even though I'd observed most of this before. But included there was my one new object for the night:

NGC 7339 -- an elongated low surface brightness smudge in the same field of view with N 7332, which I had seen before. The two form a nice pair, with relative alignment near perpendicular. 7332 is also elongated, but smaller and higher surface brightness with a brighter center. I observed these using 7mm.

Among other objects, I checked out the four "Fleas". I just barely managed to detect them all, but they were all just little AV smudges -- no detail in any of them. With 7mm, I got:

N 7335 -- held 75% with AV
N 7340 -- 75% AV
N 7337 -- 40% AV
N 7336 -- 20% AV

Mars showed no detail -- the seeing was pretty poor.

It was pretty cold, but not much wind or dew, so reasonably comfortable.

George Feliz and I did star counts in Perseus directly overhead and came out around 5.9 to 6.0. The transparency was a bit off. My SQM read variously 20.95 through 20.98.

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