NASA Postpones Asteroid Probe's Launch to July 15

The launch of NASA?s Dawn spacecraft has met a new delay, with liftoff set for no earlier than July 15, the space agency said late Friday.

NASA spokesperson George Diller said that Dawn mission managers opted to delay Dawn?s launch towards the asteroids Vesta and Ceres nearly a week from its planned Monday launch. Bad weather and mechanical glitches with a tracking aircraft prevented Friday and Sunday launch attempts.

By July 15, a tracking ship should be in place to observe Dawn?s launch atop a Delta 2 rocket, Kurt Lindstrom, NASA?s Dawn program executive, told SPACE.com Friday. The ship, he added, is already en route towards its position on the Atlantic Ocean.

NASA?s Dawn spacecraft is the agency?s first to orbit two planetary bodies and will study a pair of very different asteroids. The $449 mission is an eight-year trek that will send Dawn first to bright, dense Vesta in October 2011 and then on to the dimmer, spherical Ceres in February 2015. The two space rocks are the largest in the solar system, with Ceres - which is also considered a dwarf planet - containing up to half of the total mass of material in the Asteroid Belt running between the orbits of Mars and Jupiter, mission managers said.

Researchers hope that studying the two asteroids and comparing their differences will shed new light on the origins of the solar system and its planets.

NASA has until July 19 to launch Dawn before standing down to allow preparations for the planned Aug. 3 liftoff of the agency?s Mars Phoenix lander. Should the mission miss its July window, NASA could reattempt the space shot between September and October for an added cost of $25 million for new rocket components.

But by late October, Vesta and Ceres will be moving away from one another, making a rendezvous with both asteroids difficult for Dawn for any later launch attempts, Chris Russell, Dawn?s principal investigator, said Friday. They won?t near each other again for about 15 years, he added.

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