NASA Plans 3rd Try to Launch Pluto Mission

NASA Plans 3rd Try to Launch Pluto Mission
By MIKE SCHNEIDER, Associated Press Writer
1 hour, 11 minutes ago



NASA scientists hope the third time is the charm for their $700 million unmanned mission to Pluto.

The space agency planned to make a third attempt to launch the New Horizons probe on Thursday, a day after a storm knocked out power at the Maryland-based laboratory that will command the mission.

Strong winds in Laurel, Md., knocked out power at the John Hopkins University Applied Physics Laboratory and mission managers were wary of launching the spacecraft without backup power at the facility.

"The air conditioning was off. The flight controllers were sitting there wiping sweat," said Alan Stern, the mission's principal investigator. "If they were dealing with any spacecraft issues, which first day out of the box a lot of spacecraft have, you can't concentrate like that."

High winds at the launch pad also kept the spacecraft from lifting off on Tuesday. Winds in the Orlando area were expected to be 10 to 15 mph Thursday.

Scientists have been working 17 years on the nine-year voyage to Pluto, and they were unfazed by the back-to-back postponements.

"Two or three days doesn't mean a hill of beans," Stern said.

The space agency has until mid-February to send the spacecraft on its way, but a launch in January would allow the spacecraft to use Jupiter's gravity to shave five years off the 3-billion-mile trip, allowing it to arrive as early as July 2015.

The spacecraft is about the size and shape of a concert piano attached to a satellite dish. It will study Pluto as well as the frozen, sunless reaches of the solar system known as the Kuiper Belt. Scientists believe that studying the region's icy, rocky objects can shed light on how the planets formed.

The planned launch has drawn attention from opponents of nuclear power because the spacecraft is powered by 24 pounds of plutonium, whose natural radioactive decay will generate electricity for the probe's instruments.

NASA and the Department of Energy estimated the probability of a launch accident that could release plutonium at 1 in 350. As a precaution, the agencies brought in 16 mobile field teams that can detect radiation, plus air samplers and monitors.

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On the Net:

New Horizons Mission: http://pluto.jhuapl.edu

Nuclear protesters: http://www.space4peace.org