Word: sailing
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Instead, the J.P.L. scientists proposed taking advantage of a free and virtually inexhaustible source of power: the pressure of sunlight. Moving at 300,000 kilometers (186,000 miles) a second, the photons from the sun would exert force on the large sail-just as a handful of sand, thrown against the sail of a toy boat, can push it through the water...
...J.P.L. project, which has a $5.5 million NASA grant, calls for a kitelike framework covered by a square of plastic film measuring a huge 800 meters (2,600 ft.) on a side. The thin sail (ordinary plastic kitchen wrap is five times thicker) would be coated with an aluminum reflecting layer on the side that will face the sun, and painted a heat-absorbing black on the other side. The total weight of the sail and the instrument-packed ship mounted in a hole at its center will be only 5,000 kilograms (11,000 lbs.)-a payload that could...
Still, the huge sailer poses a problem. The sail must be carried aloft furled (folded, it will fit into a package of only one cubic meter) and the framework assembled far beyond the atmosphere. Luckily, NASA is readying a suitable ferry: the space shuttle. Capable of carrying the sail and framework in its large equipment bay, the shuttle should be in regular use by the proposed launch date for the sailing ship: January...
Once the package has been hauled by the shuttle into near-earth orbit, a small rocket will push it to escape velocity. At about 100,000 kilometers (60,000 miles) above the earth, the framework will be assembled and the sail deployed automatically...
Ground controllers will then begin navigating the craft into closer and closer orbits of the sun by properly trimming the sail. Then they can put the ship-moving at a top speed of 198,000 kilometers (124,000 miles) an hour-on a course to intercept Halley's comet in March 1986. Jettisoning the sail, and "flying station" just two kilometers above the comet's head, the ship will take TV pictures and readings to determine the visitor's composition and origin. Says J.P.L.'s Murray: "We don't have a clue about comets...