NASA scientists are counting the days until the launch of New Horizons, the first spacecraft to visit Pluto and the Kuiper Belt in the far reaches of our solar system. The unmanned, 1,000-pound spacecraft is scheduled for liftoff from the Kennedy Space Center on January 17, 2006.
Set to reach Pluto in 2015, New Horizons will study the planet's atmosphere, which is seeping gradually into space, and catalog craters on the surface of Pluto and its moon, Charon. The spacecraft also will study at least one "ice dwarf" in the Kuiper Belt, which consists of numerous comet-like objects and frozen debris that orbit the Sun from a distance beyond Neptune.
In 1930, U.S. astronomer Clyde Tombaugh discovered the frozen, ninth planet, located more than 3.6 billion miles from the Sun. Scarcely 1,400 miles in diameter, Pluto is only slightly larger than an asteroid. The discovery of Charon came in 1978. Because Charon is about half Pluto's size, they function together as a binary-planet, with a gravitational center between the two. Astronomers discovered the Kuiper Belt in 1992.