O R A C L E    O B S E R V A T O R Y Report 13-14 April 2007

The weather forecasts were good so off I went to Oracle Observatory. I left home at 0450 PDT Friday morning and arrived at Oracle at 1315 MST. The temperature was 57°F under partly cloudy skies with a strong breeze blowing. Here's how the sky appeared:

I decided to set up the tent but delayed setting up the telescope until the sky situation became clearer (pun intended). Four hours later I noticed this cumulonimbus to the North:

After awhile I determined that it was moving easterly and the sky was clearing up nicely. I decided to set up the telescope. Here's the setup; unlike in the past, I set up the LXD75 tripod with its legs extended to raise the telescope to a more comfortable viewing position. This made it easier to view through the Nikon D70 DSLR viewfinder with the camera attached to the Meade Off-Axis Guider on the 8" Schmidt-Cassegrain telescope.

By Sunset at 1853MST the sky was clear with a temperture of 50°F.

Shortly after Sunset I began observing. First up was Venus, shining brightly high in the western sky. It showed a nice gibbous phase but its image was very unsteady in the eyepiece, even at low magnification. I then slewed the telescope up towards the Zenith to view Saturn. Unfortunately, even though almost straight up, Saturn was also very unsteady. I decided to try some test photographs of Saturn using the Off-Axis Guider and D70. Here's the best one; as I have previously experienced, focusing through the Off-Axis Guider in the D70 viewfinder was a challenge. This was compounded by poor seeing that was becoming very evident. This exposure was 1/30th second, ISO 1600, and cropped from the original Raw image. You can see the "golden" color that Saturn typically has along with the Rings. You can just make out a cloud band in the atmosphere of Saturn.

At 2100MST, temperature 40°F, I decided to try some Deep Sky astrophotography. Unfortunately the seeing conditions were very poor; stars were unsteady and generally there was a lack of contrast against the darker sky. This was obviously a poor night even though the skies were clear (lacking visible clouds). I eventually gave up and called it a night, hoping for better conditions the next night.

The next morning was clear and at 0950MST it was 67°F with a slight breeze. I did some solar observing with my Coronado PST (Personal Solar Telescope). The Sun was nice with a couple of prominences visible, although no sunspots were visible. I then spent the rest of the daytime hours reading (Sky and Telescope magazine) and photographing various plants and creatures around Oracle Observatory. Here are some of those photographs (in order: Desert Thistle, unidentified small yellow flowers, American Goldfinch, Phainopepla, Turkey Vulture, unidentified ant, unidentified cactus, unidentified bird, Desert Cottontail Rabbit).

As sunset approached the sky was mostly clear with the exception of near the Sun. But that made for a pretty sunset!

After sunset I spent some time observing Venus. The sky was somewhat steadier this night. I attached a Moon Filter on my 6.4mm eyepiece (312X); this significantly reduced the glare from bright Venus and allowed easy viewing of the gibbous phase. I then removed the Moon Filter and attached a Variable Polarizer Filter; that was even better. I then moved to Saturn, which was much better than the previous night. A cloud band was visible and the Cassini Division in the Rings was visible. I was able to use the 6.4mm eyepiece plus a 2X Barlow Lens (for a magnification of 624X) and see a rather nice view of Saturn.

By 2010MST the western sky was dark enough to take a picture of the Hyades cluster, Venus, and the Pleiades. This photograph is a 20 second unguided exposure taken with the Nikon D70 DSLR mounted on a photographic tripod, 55mm focal length, ISO 1600.

I spent the next hour observing several Deep Sky Objects using a Tele Vue 35mm Panoptic eyepiece (57X) on the 8"SC. Several galaxies, open clusters, globular clusters, and nebulae were viewed. All were lovely in the Panoptic eyepiece. Overall, there was much better viewing than on the previous night. Images were steady and the sky contrast was much greater.

Unfortunately a strong breeze came up about 2110MST and at 2125MST, temperature 55°F, I decided to pack up the telescope since the breeze was making the telescope move around too much for effective viewing. After packing all the telescope gear in the car I went into the tent and listened to some old time radio shows on my iPod mini. Eventually I went to sleep; I got up about 0530MST Sunday morning and began packing up the tent for the drive back home. I left Oracle Observatory at 0645MST and arrived home 9 hours later (traffic was bad due to a rain storm from Palm Springs to Riverside).

As a result of my continuing difficulties to determine a good focus through the Off-Axis Guider I decided to purchase a Nikon DG-2 Magnifying Eyepiece. I will try it out on my next trip to Oracle Observatory.

Until next time.