NASA eyes dark energy, outer solar system missions

The U.S. space agency is planning a mission to better understand a mysterious form of energy in the cosmos and an ambitious unmanned journey to the outer solar system, NASA officials said.

NASA would initiate seven new science missions in fiscal year 2009 that starts Oct. 1 under the budget President George W. Bush proposed to Congress this week. NASA's proposed $17.6 billion budget includes $4.4 billion for science missions.

"In fact, we have more new starts in this budget for science than in the last three years combined," Alan Stern, who leads NASA's science missions, was quoted by Reuters as saying in an interview.

NASA is planning to begin work on a mission to send a spacecraft to either Jupiter or Saturn -- the two biggest planets in the solar system -- with the idea of orbiting one of three moons of these two outer solar system giants. Launch is seen by 2017, with the mission cost pegged at $2.1 billion.