Moving in on the mysteries of Mars
`MARTIANS are intelligent, stand 7 feet, 6 inches, to 8 feet tall, have large ears, [and] Chinese features.'' So said Mansfield Robinson of Royden, England, who claimed to commune with Martians telepathically when ``their'' planet made a close pass by Earth in 1924. Well Mars has come especially close again. It offers what Sky and Telescope magazine, which resurrected that quotation, calls ``the best view to Earth-based [observers] since August 1971.'' But this time we won't be speculating about the nature of Martians, nor will United States Navy radio stations stand by to pick up any Martian communications, as they did in 1924.
We have a different perspective on the Red Planet now. We have indeed heard Mars signals - coming from our own robot spacecraft. We look forward to more such communication when the two probes of the Soviet-led project to explore the martian moon Phobos arrive there next January and February. We are beginning to perceive Mars as part of our own domain rather than as an alien object ``out there.''
This adds interest to the gleaming spectacle Mars offers. It's easy to spot the planet. It rises soon after sunset as one of the brightest objects in the sky. It will provide an especially striking display Sept. 25 and Oct. 22 when it's directly south of the moon (as it was Aug. 29).
Mars is taking up a position astronomers call opposition. That means sun, Earth, and Mars will be exactly in line with Earth between the other two bodies (see diagram). This occurs at 4 minutes past midnight Sept. 28 (Greenwich time; 8:04 p.m. Sept. 27 Eastern time). But Mars actually comes closest to Earth Sept. 21 - about a day before the autumnal equinox that marks the beginning of fall.
At that time, the two planets will be only 36,545,000 miles (58,813,594 kilometers) apart. This allows the Phobos probes, launched July 7 and 12, to reach Mars in just 200 days along a 120 million-mile (193,121,666-km) course.
As our martian perspective changes, so too does the planet's symbolism. Mars and its moons were named for the old god of war and his companions Fear and Dread. They now symbolize international cooperation in enlarging our knowledge of the solar system.
With the Phobos expedition and the US spacecraft Voyager 2 flyby inspection of Neptune next year, that knowledge should substantially increase. Our explorations have not yet turned up any signs of extraterrestrial life. But they have shown that, with advancing technology, we can eventually learn to live on Mars and on our own moon, as well as in orbiting space stations.
One day, there probably will indeed be Martians with Chinese features and with the features of Earth's other peoples as well. They will be the children of Martian colonists. And, as Carl Sagan and other planetary visionaries remind us, some of those Martian pioneers have probably already been born.
A Tuesday column. Robert C. Cowen is the Monitor's natural science editor.
