dipper@utastro.UUCP (Debbie Byrd) (05/11/85)
A red star and a red planet appear low in the west after sunset. We'll tell you which is which -- after this. May 11 Mars and Aldebaran Keep your eyes near the western horizon after sunset Saturday evening -- and you'll see two red objects -- one a planet and the other a star. The red planet is Mars and the star is Aldebaran -- now near each other, very low in the west after sunset. The planet Mars is the reddish object on your right as you face west. The light we see from Mars doesn't shine from within the red world -- instead it's reflected sunlight. Planets typically show a steadier light than the twinkling stars -- but Mars is now so near the horizon that we're seeing it through a great thickness of atmosphere. That atmosphere may be causing Mars to twinkle a bit, too. Mars is a member of our solar system -- gravitationally bound to the Sun. Aldebaran is a distant giant sun itself -- much larger than OUR mother star -- and millions of times farther away than Mars. But right now both objects lie nearly in the same line of sight in space, as seen from our earthly vantagepoint. As our planet swings around the sun, our line of sight towards both Mars and Aldebaran is also slanting towards the sun. Soon the solar glare will block our view of both celestial objects -- they'll be drowned in the glare of the sunset. Even now Mars and Aldebaran are so near the sun on the dome of the sky that they may be hard to see. Watch carefully for two red objects low in the west -- and each evening you'll notice the two appear closer to the horizon. Script by Diana Hadley. (c) Copyright 1984, 1985 McDonald Observatory, University of Texas at Austin