Sunday, February 21, 2010

Clouds chasing us

Saturday, February 20: It has been a very cloudy year so far -- only two "officially" clear days since last December. There may have been several clear sky nights but they were so extremely cold that the warmth of the house had a stronger pull than did the stars! There was just enough clear sky at the 7:00 starting time that I opened Stephens Memorial Observatory to visitors for the first Open Night of 2010. Seeing conditions, however, were mostly fair to poor so our visitors got mostly not-so-exciting looks at the Orion Nebula (M42) before Earthly clouds obscured the glowing clouds in Orion some 1,599 light years distant. For only a very few minutes in the entire evening a clearing appeared in the clouds and the nebula splendidly burst forth in the telescope eyepiece; unfortunately only three or four people got to enjoy the view. I only got a glimpse at it myself before urging visitors to look but what I saw was marvelous -- lovely, silken, glowing clouds cradling a nest (The Trapezium) of brilliant "little" stars. Magnificent. Turning the telescope to the east we were able to see planet Mars as a small pinkish disk -- not bad for sky conditions but not good enough to see a polar ice cap, much less any surface markings. Mars was relatively close at 67.7 million miles from Earth. As clouds overhead swallowed Mars, the telescope was swung around and aimed at Earth's Moon, clouds scudding across its face. Cloud cover greatly reduced the Moon's brilliance and gave it an unusual, low-contrast, gray appearance. Everyone got a look at the first-quarter Moon in surprising detail. Along about 8:00 the thickening clouds hid the last traces of Luna and I closed the doors and the dome shutter against the 32-degree night air. About 35 visitors had come through in the space of one hour and, despite the poor conditions, most seemed pleased with the experience.