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Next Stop: Mars

--By Joe McGowan

Two hardy explorers are expected to set out next month to find evidence of water on Mars. They are NASA-built robots, and they are jam-packed with the latest space-age exploration tools.

The identical twin robots--called Mars Exploration Rovers--will take off on separate Delta II rockets from Cape Canaveral, Florida. The first trip is slated for early June. They will travel more than 300 million miles before landing on Mars in early 2004. Their mission: to look for dried-up lakes and other signs of water, clues that life once existed on the Red Planet.

A BOUNCING, ROLLING TOOLBOX

Landing on Mars will be tricky. Separate landing sites on opposite sides of the planet were chosen for safety and scientific reasons. Each 400-pound rover will be tightly folded into a pyramid-shaped platform. Parachutes and braking rockets will slow the fall through the atmosphere to 60 miles per hour. A cocoon of airbags will inflate around the vehicle to cushion its landing. The rover will probably bounce 13 times and roll half a mile. When the platform comes to a stop, it will turn upright. The airbags will deflate, and the sides of the pyramid will fall open. Over four days, the rover will take shape piece by piece and then get rolling.

The six-wheeled rovers will be able to travel 100 yards--the length of a football field--each Martian day. Their tools, including a 3-D camera, will act as the eyes, hands and feet of the 120 scientists guiding the mission on Earth. A RAT (rock abrasion tool) can drill through rocks to show what's inside. Lollipop-like antennae will enable the rovers to "phone home" to NASA. The agency expects the daring duo to run for about 90 days and set the stage for future explorations of Mars, including possible human visits there.

"These rovers are like the great explorers who knew of a place and went to see what was inside," project manager Jim Erickson told TFK. "Future missions will depend on what they achieve."

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