After numerous delays and the incertitude that hovered over this week’s potential launch, NASA was finally forced to give up the idea of a near-future launch for the DAWN space craft, postponing it until September.

NASA’s DAWN space program, which costs $343.5 million (not including launch vehicle) and consists of $267 million spacecraft development and $76.5 million mission operations, has received a major setback on July 5, because of heavy thunderstorms above Kennedy Space Center.

Scientists were hoping for a July 15 lift-off, but workers are now clearing the way at Cape Canaveral Air Force Station for another launch, that of Mars Phoenix Lander, which is scheduled for early August.

The Mars Phoenix Lander preparations and the limited amount of launch-windows in July are the main reasons cited by NASA spokesperson George Diller to justify DAWN’s new delay.

"A September launch for Dawn maintains all of the science mission goals that a July launch would have performed," Diller said in an update from NASA's Kennedy Space Center in Cape Canaveral.

The DAWN spacecraft is 1.64 meters (5.4 feet) long, 1.27 meters (4.2 feet) wide and 1.77 meters (5.8 feet) high.

The DAWN mission will study the asteroid Vesta and dwarf planet Ceres, celestial bodies believed to have accreted early in the history of the solar system. The mission will characterize the early solar system and the processes that dominated its formation. Both bodies lie in an orbit between Mars and Jupiter and are building blocks left over from the solar system's formation some 4.6 billion years ago, at the same time and in similar environments as the bodies that grew to be the rocky inner planets, Mercury, Venus, Earth and Mars.

NASA must launch Dawn before Oct. 20, after which the Vesta and Ceres will start moving away from each other in their respective orbits, the mission's principal investigator Chris Russell has said. They two space rocks will be near each other again in about 15 years, he added.