Wednesday, March 31, 2010

Unexpected Saturn


Unexpected business led me to visit Stephens Memorial Observatory Tuesday night. Since I was there and the sky was nicely clear, I decided to open the dome and do a little observing.

Orion is low in the west these nights and the great nebula (M42) was actually only visible through the bare limbs of the neighbor's trees. The view was splendid, however, and at low magnification, the cloudy expanse took on a fan shape. The stars of the Trapezium were clearly displayed, nestled in the gauze.

Using star Sirius to set R.A., and my notebook computer's The Sky software, I was able to use the telescope's ancient dials to locate the "twin" star clusters M46 and M47 -- not visible to the unaided eye. Declination settings are not visible on the old scope at this time so I had to do some fishing. Still, it was gratifying to be able to get in the right neighborhood using the telescope's century-old devices. The clusters were more attractive through binoculars --a glowing path of cloud across the dark field-- than through the telescope though, at low magnification, M46 filled the eyepiece with diamond-dust stars.

Turning the telescope further east as the Moon was rising, I located Saturn. The ring system is still close to edge-on and opposition took place only a few days earlier (March 22). The planet was crisp and bright and, faintly visible nearby, were some of the Ring World's family of moons. It was a lovely sight. I had my camera with me so tried a few afocal (hand-held, lens-to-eyepiece) shots. At settings: ISO 800, f/8, 1/10 sec., I got a fairly good shot (seen here, cropped to imitate an eyepiece view) that depicts the ring plane's angle and even hints at the rings' shadow on the planetary body. Of course, the moons don't show at all being much too dim by comparison.

I closed up at about 10 PM with the Full Worm Moon rising and drowning out the light-songs of everything nearby. A good night of unexpected astronomy.

Sunday, March 28, 2010

Hazy sky but good turnout

Saturday, March 27: During the Public Open Night we had 48 visitors come to the Observatory. Despite high, thin clouds, we were able to enjoy acceptable views of the Moon at about 30-power and 133-power magnifications. We got the season's last look at the Orion Nebula but the view was poor due to those thin clouds above our heads -- looking at clouds (the nebula) through clouds (Earth's weather) is not very good. When Saturn rose high enough to clear neighboring trees and thickening clouds near the horizon the big telescope was turned in that direction. Though not as crisp a view as a good night would afford, we were able to see the planet's ring system nearly on edge to us and, during times of somewhat better seeing, make out the shadow of those rings falling on the planetary disk. We could also see several of Saturn's moons including Titan. (Note: Saturn was at opposition on March 22.) Sky conditions continued to deteriorate so that, by closing time, about the only object visible in the sky was a bright but very hazy Moon. Still it was a good night enjoying views of our universe from Stephens Memorial Observatory. Temperatures in the upper-40s, light wind, Moon was waxing gibbous.