Windy weather has once again thwarted NASA's attempt to launch two gravity probes to the moon today (Sept. 10) on a mission to study the inside of the moon and its gravity field.
The two Grail spacecraft were scheduled to launch on an unmanned Delta 2 rocket from the Cape Canaveral Air Force Station in Florida this morning at 8:29 a.m. EDT (1229 GMT), but stubborn high-altitude winds – the same thing that forced NASA to stand down during initial launch attempts on Thursday (Sept. 8) – caused yet another delay.
A second opportunity to launch the Grail mission this morning is available at 9:08 a.m. EDT (1308 GMT), but if weather conditions do not improve, NASA will have to wait until tomorrow before they can try again. [Photos of NASA's Grail Moon Gravity Mission]
Another chance on Friday (Sept. 9) was called off to give engineers time to assess the rocket's propulsion system after a potential glitch was detected. After a series of reviews, the team concluded that there are no issues with the rocket or its propulsion system, NASA officials said.
The $496 million Grail mission will closely analyze the composition of the lunar interior, and the twin probes will make detailed and precise maps of the moon's gravitational field. The three-month expedition is expected to help scientists uncover clues of the moon's origin and evolution.
Grail's observations should also shed light on how other large, rocky bodies in the inner solar system were formed.
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Denise Chow is a former Space.com staff writer who then worked as assistant managing editor at Live Science before moving to NBC News as a science reporter, where she focuses on general science and climate change. She spent two years with Space.com, writing about rocket launches and covering NASA's final three space shuttle missions, before joining the Live Science team in 2013. A Canadian transplant, Denise has a bachelor's degree from the University of Toronto, and a master's degree in journalism from New York University. At NBC News, Denise covers general science and climate change.