20x80 Binocular Session

Date: 9 March 2007 U.T.
Time: 5:37 - 6:45 U.T.
Binoculars: 20x80 (hand held)
Seeing: Good
NELM: 6.0 - 6.5
Temperature: +28 F (-2 C)

High Humidity and Clouds: A small amount of rain fell during the day prior to this session. The floor of my open-air observatory remained damp. Clouds didn't dissipate until sometime after sunset. Due to these conditions I decided to not set up a telescope. By the time of the observation a fairly thick layer of frost had formed on the porch, etc.

At the start of the binocular session my sky was clear in the west. The rest of the sky seemed to be covered with very thin clouds. Later, conditions improved enough to allow me to see most of the objects that I wanted to observe.

M41 is an open star cluster in Canis Major. Someone had recently mentioned on the newsgroup, sci.astro.amateur that they were disappointed in the appearance of this cluster in their 130mm telescope. I made a response as to some possible reasons, and mentioned that M41 was visible to the unaided eye under a sufficiently dark sky. So, with a clear sky, I decided to pay a visit to M41.

Sure enough, the cluster was a relatively easy object to detect with the unaided eye. Through the binoculars M41 was resolved into numerous individual stars. I found the view to be 'rather nice' despite the cluster's low altitude in my southwestern sky.

Galaxies in Leo, Virgo and Coma Berenices: Next on my agenda were the Messier galaxies in the Virgo region. The above sketch has north up and west to the right. It shows the general appearance of M65 (the galaxy to the right of center), M66 (the galaxy to the left of center), and NGC 3620 (the fainter galaxy north of the other two). Galaxies tend to look like faint,fuzzy stains against the background sky when observed with 20x80 binoculars.

In addition to the three objects mentioned above, I observed the following galaxies: M58, M59, M60, M64, M84, M85, M86, M87, M88, M89, M90, M91, M95, M96, M98, M99, M100, and M105.

Near the end of the session the Moon rose. The high humidity scattered the moonlight, making the sky much brighter than it would have otherwise been.

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'.

Pleiades Star Cluster

Date: 19 December 2006 U.T.
Time: 3:04 - 3:51 U.T.
Telescope: 30cm Newtonian
Magnification: 38x
Seeing: Fair
NELM: 6.3
Temperature: +15 F (-9 C)


The above sketch shows the Pleaides Star Cluster, also known as M45 and The Seven Sisters. It's located at RA 3hr 47', Dec +24 07'. South is up. West is to the left. The circular field is 1.7 degrees in diameter. Note the nebulosity visible around a few of the brighter stars.