New Horizons probe bound for Pluto on nine year journey

January 19, 2006

Earlier today, an Atlas V rocket carrying the New Horizons unmanned spacecraft probe lifted off from Pad 41 at the Cape Canaveral Air Force Station bound for the last unexplored planet in the solar system, Pluto, at 11 am EST, after two scrubbed liftoffs the past two days because of bad weather.

The probe will take a nine-year, 3-billion-mile (5-billion-km) journey to Pluto, the ninth and final planet in the solar system. It is expected to take photos of the planet that are of the highest resolution ever, since current photos of Pluto are not of the highest quality, even those taken from Hubble Space Telescope. It will also attempt to characterize the global geology and morphology of the planet and study the atmosphere of the planet.

After accelerating to 36,000 mph, it will pass the moon in nine hours. The probe will pass by Mars in April and then head on to Jupiter where it will pass by in February 2007 and continue on. Around July 14, 2015, the probe is expected to fly by Pluto and its moon Charon, after which the probe could possibly make a flyby of one or more Kuiper Belt objects. (KBOs).

New Horizons is powered by an onboard nuclear electric generator, known as a radioisotope thermoelectric generator, using 24 pounds (10.8kg) of plutonium as its radioactive "fuel" source. Some anti-nuclear activists feared that the launch could end in an accident with radioactive material being spread over a wide area. The chances of such a disaster were calculated by the United States Department of Energy at 1 in 350.

The Tuesday liftoff was postponed because of high winds at the launch site. The Wednesday launch was stopped after a severe storm near Laurel, Maryland knocked out power at the Johns Hopkins University's Applied Physics Laboratory, which hosts the flight control center for the mission.

As a side note, the probe is also carrying some of the ashes from Clyde Tombaugh, the discoverer of Pluto.