Posted by tourdemars to Life on Mars at December 23, 2003 12:00 PM

Mars passed closer to Earth this summer than it had in thousands of years, and now three emissaries from Earth are about to repay the neighborliness — and then some. They are set to descend on the planet, and stay. The three visiting spacecraft, two of them carrying robotic roving vehicles, will be searching the Martian surface for signs of life or conditions conducive to life, at least in the distant past. Their quest is the latest scientific response to an abiding human fascination about the world next-door, a place cold and arid but sufficiently Earthlike to inspire visions of extraterrestrial life.