The planet Jupiter hangs high in the western sky in mid-evening this week, with the bright stars of the Summer Triangle off to its right. The crew of the "China Clipper" used these and other stars as navigational aids during its first crossing of the Pacific Ocean 75 years ago. Celestial navigation was used by pilots for decades, and by ship's navigators for centuries. [Tim Jones]
A Star to Steer Her By
When a modern airliner soars over the Pacific Ocean, it’s guided in part by a constellation of satellites. The satellites tell the pilots the position of their aircraft to within a few feet.
But when Pan American pilot Ed Musick headed the “China Clipper” into the Pacific 75 years ago today, he was guided in part by constellations of stars.
Musick and his crew were pioneering a new route: from San Francisco to the Philippines via flying boat. They headed west on November 22, 1935, carrying not passengers, but mail -- the first trans-Pacific airmail service.
Some of the trip was guided by radio transmitters in San Francisco and Honolulu. But navigator Fred Noonan also had to rely on the stars.
Celestial navigation had been practiced for centuries. The stars guided Polynesians between Pacific islands, and European explorers across most of the world’s oceans. When aircraft started flying across the oceans, they, too were guided by the stars.
Celestial navigation involved using a small telescope to plot the angles of the Sun, Moon, and stars -- their height above the horizon, for example. Navigators also needed printed tables of star positions, and a good clock.
The “China Clipper” relied on some of the same stars that are visible tonight -- stars like Vega, which is in the west at sunset, or Fomalhaut, in the south -- celestial beacons for an historic trip across the Pacific.
Script by Damond Benningfield, Copyright 2010
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