PASADENA, Calif. -- The Voyager 2 spacecraft, racing toward a close encounter with Neptune late Thursday, has cost the average American taxpayer about half a candy bar per year since the project's birth in 1972.
According to 'The Voyager Neptune Travel Guide,' published by the National Aeronautics and Space Administration, the Voyager project will have cost $865 million through the Neptune flyby Aug. 24, or roughly 20 cents per U.S. resident per year.
The Travel Guide lists a variety of 'gee whiz' facts about Voyager, including:
-Total Work Needed for Voyager: 11,000 person-years through the Neptune encounter, or one-third the amount of effort needed to build the great pyramid at Giza.
-Data Return: 5 trillion 'bits' from Voyager 1 and 2, or enough for 6,000 sets of the Encyclopedia Britanica.
-Radio Signal Strength: NASA uses giant antennas in Australia, Spain and California to maintain constant touch with Voyager 2 despite the Earth's rotation. The strength of the radio signals from Voyager 2 that must be detected is about .000000000000001 watts, or 20 billion times weaker than the power level of a typical digital watch.
-Parts Total: Each Voyager is made up of 65,000 major pieces of equipment with the equivalent electronic complexity of 2,000 color television sets.
-Radiation Levels: At Jupiter, each Voyager was subjected to a radiation dose of 1,000 the lethal level for humans.
-Stability: Voyager 2 can be maneuvered at rates 30 times slower than the hour hand on a clock to allow for time exposure photography with light levels 900 times fainter than those on Earth.
-Power: Voyager 2's instruments require about 400 watts of power, about one quarter of the energy used by an average home.
-Thrusters: A Voyager thruster would have to fire six hours to accelerate a car to 30 mph on a level, frictionless road.
-Trajectory: Voyager 2's trajectory is so accurate the spacecraft will be within 22 miles of its planned position upon arrival at Neptune after a total flight of 4.4 billion miles.
-Distance Facts: Interplanetary distances are measured in astronomical units, or 'AU.' One AU equals about 93 million miles. It would take 163 years to travel this distance at 65 mph. Through the Neptune encounter, Voyager 2 will have traveled 47.6 AU.
-Velocity: Voyager 1 is leaving the solar system at a speed of 3.5 AU per year, or about 37,000 mph; that's fast enough to travel one and a half times around the world in one hour. Voyager 2 will depart the solar system at a speed of about 36,000 mph.
-TV Resolution: Each narrow-angle Voyager TV camera can read a newspaper headline at a distance of .62 miles.
-The future: Both Voyagers will continue their lonely journeys across the cosmos for millenia to come. But around 2017, their nuclear generators will no longer be able to power their instruments and the missions will effectively come to an end.