Mars
Image: MAURIZIO DI SCIULLO, Courtesy Sky & Telescope

UFO reports may well rise this month as people mistake a bright, low-hanging object in the night sky for invading Martians. In fact, it's only Mars. Today the Red Planet reaches what is known as opposition, a point at which it is on the opposite side of Earth from the sun. Making it even more visible, Mars will be closer to Earth than it has been in more than 12 years, at a mere 42 million miles away.

"Because Mars is a small planetjust half the diameter of Earthit only puts on a good show when it's near opposition," says James White, executive director of the Astronomical Society of the Pacific. "And this is one of the better oppositions. So the next month will be a great time to go outside and view Mars, whether you're using your unaided eye, binoculars or a telescope."

Don't worry if you miss this year's opportunity, though: in August 2003 Mars will come even closer, within 34.6 million miles, and should thus put on an even better show. "On that date, the Earth-Mars distance will be the smallest it has been in at least 5,000 years, and probably for a good while before that," says Myles Standish of the Jet Propulsion Laboratory in Pasadena, Calif. Following that event, the next comparable opposition won't occur until 2287.