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A monthly look at the night skies of Wyoming, written by Ron Canterna, professor in the University of Wyoming Department of Physics and Astronomy. The Milky Way starts in the eastern horizon, rides high across the sky directly overhead, finally settling in the western horizon. Overhead are two prominent constellations, Pegasus and Cassiopeia. Pegasus, the winged horse, is slightly to the south of the Milky Way, and is recognized by its famous Great Square. You will also notice the queen Cassiopeia, easily recognized by its stretched out "W" or "M" star pattern. (The W is for Wisconsin; the M for Maine!) Rising prominently in the east around midnight is Orion the hunter, a definite sign of the arrival of winter. This majestic constellation, known for its three-star belt and its Great Nebulae, which outlines its sword, is really the location of current and active star formation. Say goodbye to the summer triangle as it sets around 8 p.m. Planet Hunters: After sunset Jupiter is in the south horizon and Mars will rise in the east around 11 p.m. followed by Saturn at 3 a.m. This year's Leonid meteor shower peaks the nights of Nov. 17-18 and we expect to see 40 meteors per hour. It is best to see this event after midnight. November 2009 Interest: Water on the Moon: II Clearly water is not flowing freely on the moon and most likely pools of water are not hidden below the surface in permafrost layers. However, the findings from three spacecraft (the Indian Chandrayaan-1 lunar probe, NASA's Cassini mission and Deep Impact spacecraft) note that the moon is hydrated -- that is, it shows strong evidence of minimal hydroxyl molecules or water presence over the entire surface. There are "daily" variations due to changes from the sun's radiation on local surfaces. There are some concentrations near the south pole and in the deep shadows of craters. How did the water get there? Some may have arrived from water-bearing comets imploding on the surface. However, most lunar scientists now believe the major source comes from the interaction of the solar wind, which is primarily from protons (the positive-charge nucleus of a hydrogen atom). These fast-moving protons (up to 750,000 miles per hour) interact with the lunar rocks, which mainly are made up of silicates (Si O4). If the charged particles break up the oxygen bonds in the rocks, the hydrogen and oxygen can bond for hydroxyl or water. Naturally, we should expect to hear more on this subject since it has great consequences on the future of manned space missions. For more information, visit the Wyoming Skies home page (http://wyoskies.uwyo.edu) or send an e-mail to canterna@uwyo.edu.
Posted on Thursday, October 29, 2009 |