Andromeda Galaxy, Pleiades & Telescope Care

Date: 25 December 2006 U.T.
Time: 4:50 - 5:18 & 5:45 - 6:05 U.T.
Telescope: 30cm Newtonian
Magnification: 38x
Seeing: Good
NELM: 6.0
Temperature: +12 F (-11 C)

Prior to getting down to business:
The telescope was set up shortly after sunset, allowing Andrew a peek at the crescent moon at 80x. Later, after moonset, Ann and Andrew got good views of the Great Orion Nebula at 80x. Andrew stuck around long enough to view a few additional objects.

Starting at 4:50 U.T. I once again worked on sketching the Andromeda Galaxy (M 31). At 5:45 U.T., after having taken a break, I revisited the Pleiades Star Cluster (M 45) for yet another sketch of the associated nebulosity. As it turned out, this wasn't a very good night for these tasks; but I did the best I could under the circumstances. The difference between a 6.5 and 6.0 magnitude sky is quite noticeable when one is attempting to study faint objects or features. Nevertheless, I feel that I now have enough raw material to attempt new and improved paintings of both celestial showpieces.

Telescope Care:
By the end of the session the porch, grass, telescope, etc. had acquired a coating of frost. Yet, due to preventive procedures, I was able to avoid any frost or dew formation on the telescope mirrors -- while outdoors as well as after returning indoors.

Many years ago, after bringing in a very cold telescope, I had learned an important lesson. The telescope had been outside for several hours when the air temperature (excluding any windchill) was -20 F (-29 C). After bringing the frigid telescope indoors, the cold glass and metal attracted moisture like magnets. Before long the telescope had acquired a thick coating of ice (remember, this was after the scope had been brought inside). After more time had passed and the telescope had warmed sufficiently, chunks of ice broke off, fell to the floor, and gradually liquified. Of course, water spots persisted on the optical surfaces after the scope had completely dried.

Now I always cover all optical surfaces, tube openings, etc. before bringing a cold telescope indoors. When practical, either the entire telescope or key components are also boxed prior to bringing them indoors. Despite several recent nights of use at below freezing temperatures, the mirrors of the 30cm telescope have never had any form of condensed moisture on them. Consequently, the optics remain pristine -- no 'water spots'.