dipper@utastro.UUCP (Debbie Byrd) (10/03/85)
The two "stars" near each other in the predawn sky are really planets. More -- after this. October 3 Mars and Venus Friday and Saturday mornings are good times to see two planets extremely near each other on the dome of the sky. The planet Venus is the brightest object you'll see in the east before dawn. Very near Venus is a much dimmer reddish object -- the planet Mars. Though the two planets appear close together in the sky, in reality they're millions of miles apart. Venus is the second planet outward from the sun -- and Mars is the fourth. We're seeing these two worlds from another world whose orbit is sandwiched in between -- our Earth. From our line of sight, both Mars and Venus are located far across the solar system. They're both moving toward the far side of the sun from Earth. But the farther a planet is from the sun, the slower it moves in orbit. So while Venus is racing ahead of the Earth, we're now catching up to Mars. We'll pass between it and the sun next summer. Next Sunday Venus will be at the point in its orbit where it's nearest the sun -- called its perihelion. On October 17, Mars will be at aphelion, the farthest point from the sun in its orbit. So tomorrow and Saturday morning, Venus and Mars will be far from each other in the solar system -- and far from Earth. But they'll appear from Earth to be less than a moon's diameter apart on the dome of our sky. Look eastward an hour before dawn -- for brilliant Venus and much fainter red Mars. Script by Diana Hadley. (c) Copyright 1984, 1985 McDonald Observatory, University of Texas at Austin