Monday,  August 20, 2012 • Vol. 13--No. 037• 9 of 28 •  Other Editions

Young crescent moon, Spica, Mars and Saturn in August 20 sky

• For a lovely treat be sure to step outside right after sunset to catch a glimpse of the thin crescent moon and the triangular trio of the star Spica and the planets Mars and Saturn.
• Tonight the moon appears as a young thin crescent moon. When the moon is in this phase you can find it above the western horizon after sunset showing just a sliver of light reflected from the sun. Some people challenge themselves on spotting the first glimpse of the young moon. Astronomers call it the young moon as it is just beginning its monthly phase after new moon. The darker main body of the moon is often

visible through binoculars (or the unaided eye) as earthshine. Earthshine is sunlight reflected off of Earth onto the moon.
• Mars, Spica and Saturn have appeared close together all month long. They now form a triangle. If you have been watching this grouping through the month you have noticed the planets change position as they move in their orbits. Spica, Saturn and Mars are similar in how bright they appear to us--their magnitude--but their colors are different. The planet Mars, the fourth planet from the sun, appears reddish. Saturn, the second largest planet in the solar system and sixth from the sun, looks yellow. Spica, the brightest star in the constellation Virgo, is blue-white. Binoculars can help highlight the colors. Also, Saturn with its rings will appear elliptical instead of round.
• So, tonight, take time in the early evening to view the young waxing crescent moon and the trio of Saturn, Mars and Spica.

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