Video: Rocket carrying moon probes blasts off

updated 9/10/2011 9:47:25 AM ET 2011-09-10T13:47:25

Two identical NASA space probes are on their way to the moon after launching Saturday on a mission aimed at unlocking the mysteries hidden beneath the lunar surface.

Less than two hours after liftoff, the twin Grail-A and Grail-B probes were deployed from their launch vehicle, setting them en route to their lunar destination.

"We are on our way, and early indications show everything is looking good," said David Lehman, Grail project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We will know more about Grail's status in a few hours, after an opportunity to analyze telemetry and poll our mission controllers." [Photos: NASA Launches Grail Probes to the Moon]

Image: Rocketcam
This view shows NASA's Grail-A probe with the blue Earth as a backdrop after the moon gravity probe separated from its Delta 2 rocket. The image was captured by a video camera on the rocket, shortly after the Grail mission launch from Florida on Saturday.

The $496 million Grail mission (short for "Gravity Recovery And Interior Laboratory") will closely study the interior of the moon, from crust to core, and will map the moon's gravitational field in unprecedented detail. The three-month mission is expected to help scientists better understand the composition of Earth's natural satellite and how it has evolved since its formation 4.6 billion years ago.

Next stop: Moon
The two Grail spacecraft blasted off this morning on an unmanned Delta 2 rocket at 9:08 a.m. ET from Cape Canaveral Air Force Station in Florida, after windy weather and a technical glitch delayed the mission's launch by two days. A launch try at 8:29 a.m. ET was called off due to high-altitude winds, but weather conditions improved and the agency was able to take advantage of the day's second launch opportunity.

Saturday's liftoff marked the last planned launch of a Delta 2 from Cape Canaveral Air Force Station's launch complex. The workhorse rocket has had an illustrious career, which includes being the vehicle that sent the Mars rovers Spirit and Opportunity on their journey to the Red Planet.

About 80 minutes after the launch, the Grail spacecraft began separating from their Delta 2 rocket, an event captured by a video camera mounted to the booster. The camera beamed down stunning live views of the Grail probes as they pulled away from the rocket. A bright blue Earth served as the backdrop. [See a photo of the Grail separation here]

The two spacecraft, called Grail-A and Grail-B, are flying on an energy-efficient path to the moon and are expected to arrive at their lunar target around New Year's Day.

"We've used gravity science before; however, these have been very primitive attempts compared to what Grail will be able to accomplish," Robert Fogel, Grail program scientist at NASA Headquarters in Washington, said during a pre-launch news briefing.

Understanding the origin of the moon and how it evolved will shed light on how the rocky planets in the inner solar system formed, said Maria Zuber, Grail principal investigator at MIT.

"We have orbital reconnaissance of the surface, we have lunar samples which we can analyze in Earth labs," Zuber said. "The piece of the puzzle that has been missing in trying to reconstruct lunar evolution is understanding of the lunar interior." [Related: 20 Most Marvelous Moon Missions]

How the probes do the job
The twin probes will then enter into tandem orbits around the moon, separated from each other by a distance of about 75 to 225 miles (121 to 362 kilometers). The spacecraft will circle the moon about 34 miles (55 kilometers) above the surface.

Image: Grail probes
An artist's conception shows how the Grail probes will measure the distance between each other and send that information back to Earth.

As the Grail spacecraft chase each other around the moon, regional differences in the lunar gravitational field will cause the probes to speed up or slow down, changing the distance between them, explained Sami Asmar, Grail deputy project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.

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Microwave signals bounced back and forth between Grail-A and Grail-B will measure this distance, which will help researchers construct accurate maps of the moon's gravity. The instruments onboard the Grail probes are so precise they will be able to calculate the distance between them to within less than the width of a human red blood cell, Asmar said. [Video: Grail's Mission to Map Moon Gravity]

Zuber said the moon is a "fantastic" celestial body for learning about planetary evolution.

"It's nearby, it's accessible, and it preserves the record of what early planets are like," she said. "Other planets in the inner part of the solar system have gone through the same processes that the moon has gone through."

Outreach to students ... and tweeters
The Grail mission is also expected to raise public awareness about the moon, and special cameras aboard the probes will be used to encourage middle school students to participate in lunar science and follow along with the Grail expedition.

The so-called MoonKam project, which will capture pictures of the lunar surface for students on Earth, is being led by former NASA astronaut Sally Ride and her educational company Sally Ride Science.

As part of their public outreach efforts, NASA also invited 150 Twitter fans to attend the launch and share their experiences with the public through social media.

The agency also announced it will hold a contest for students of all ages across the U.S. to select a name for the Grail lunar probes. The contest will run from Oct. 14 to Nov. 11 and students will be invited to submit essays explaining their choice of names, Zuber said. NASA will announce additional details about the contest soon, but the winners will be announced before the Grail spacecraft arrive in lunar orbit.

NASA's broadcast of the Grail launch suffered a power outage shortly after both the Grail-A and Grail-B probes were deployed. Video was recovered shortly after, with only a short interruption to the agency's post-launch commentary.

You can follow staff writer Denise Chow on Twitter @denisechow. Follow for the latest in space science and exploration news on Twitter @Spacedotcomand on Facebook.

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Photos: 50 years of views from the moon

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  1. Up-close exploration of the moon, Earth's only natural satellite, began in 1959 when the Soviet Union launched its Luna 1 spacecraft on a flyby mission. NASA quickly followed up with missions of its own. Since then, the Europeans, Japan, China and India have launched their own lunar exploration programs. This view shows the moon as seen from the international space station. Click the "Next" arrow above to check out 11 images from the moon made over the last 50 years. (NASA) Back to slideshow navigation
  2. 1959: Far side in full view

    In October 1959, the Soviet Union's Luna 3 spacecraft - the third successfully launched to the moon - made history as the first probe to image the far side of the moon. The photos were fixed and dried on the spacecraft and beamed back to Earth. Though fuzzy by today's standards, the images showed stark differences from the near side, including relatively few dark areas, called lunar maria. (RSA via NASA) Back to slideshow navigation
  3. 1966: A restored ‘Earthrise'

    In 1966 and 1967, NASA sent a series of Lunar Orbiter spacecraft to collect detailed images of moon's surface in preparation for the Apollo program. The tapes were then put in storage. Decades later, researchers with the Lunar Orbiter Image Recovery Project collected the vintage hardware required to play back the imagery. That imagery was digitized , reproducing the images at a much higher resolution than previously possible. On Nov. 11, 2008, the project researchers released this enhanced photograph of Earth rising above the lunar surface, originally made by Lunar Orbiter 1 in 1966. (LOIRP / NASA) Back to slideshow navigation
  4. 1968: The most famous 'Earthrise'

    On Christmas Eve 1968, Apollo 8 astronauts Frank Borman, Jim Lovell and William Anders made history as the first humans to orbit the moon. They were scouting its surface for a suitable landing spot for future missions. But the sight of Earth rising above the moon's horizon caught their - and the world's - attention. The photograph, called "Earthrise," is among the most famous ever made from the moon. (NASA) Back to slideshow navigation
  5. 1969: One small step

    On July 20, 1969, an estimated 1 billion people around the world were glued to television screens to watch astronaut Neil Armstrong, commander of Apollo 11, climb down from the lunar module spacecraft for a stroll on the moon. As his foot touched the lunar surface, he famously said "That's one small step for (a) man, one giant leap for mankind." This image is a black-and-white reproduction from the telecast, showing Armstrong stepping down from the lunar module's ladder. (NASA Johnson Space Center) Back to slideshow navigation
  6. 1969: Man on the moon

    Apollo 11 astronaut Buzz Aldrin, shown here, accompanied Armstrong for the famous walk on the moon. This iconic image is one of the few that shows Armstrong on the lunar surface - as seen in the reflection on the spacesuit's visor. The astronauts walked around on the lunar surface for about two and a half hours. (NASA) Back to slideshow navigation
  7. 1994: Looking for ice

    This mosaic image of the moon's southern polar region, made by the Clementine spacecraft in 1994, suggested that the region could harbor water ice within regions of its craters that are never lit by the sun. The water ice would be left over from impacting comets. Scientists have debated the evidence for and against water ice at the poles ever since the Clementine discovery. The current era of lunar exploration could resolve the debate. If water ice exists, it could help quench the thirst of future human colonists and be used to make fuel for rockets. (NASA / JPL / USGS) Back to slideshow navigation
  8. 2006: European moon probe crashes

    On Sept. 3, 2006, the European Space Agency's SMART-1 spacecraft went out with a bang - a planned crash landing into a volcanic plain called the Lake of Excellence. The impact, shown here, was captured by the Canada-France-Hawaii Telescope. (The black lines are a processing error due to the brightness of the event.) The spacecraft was launched in 2003 primarily to test an ion propulsion system, which uses energy captured by the sun to produce a stream of charged particles. The slow-and-steady propulsion system may be used on future interplanetary missions. (Christian Veillet / CFHT via AP) Back to slideshow navigation
  9. 2007: China targets the moon

    China made its first major strides in the lunar exploration game with the launch of the Chang'e 1 spacecraft in October 2007. The orbiter was sent to make a detailed, 3-D map of the moon's surface. Premier Wen Jiabao unveiled the first image at a ceremony in Beijing, shown here. Chang'e 1's 16-month mission ended with a controlled crash. The country reportedly plans to launch lunar rovers in 2010 and 2017, and a manned mission to the moon by 2020. (Huang Jingwen / XINHUA NEWS AGENCY) Back to slideshow navigation
  10. 2008: India joins the lunar club

    The Indian Space Research Organization successfully launched its Chandrayaan 1 spacecraft on Oct. 22, 2008, for a mapping mission to the moon. A probe released from the mothership took this picture of the lunar surface during its descent to a planned crash landing at the south pole. The Indian space agency plans to use this and other data for a lunar rover mission in 2011 and, eventually, a manned mission. (ISRO via EPA) Back to slideshow navigation
  11. 2009: Japan orbiter watches eclipse

    Some eclipse enthusiasts travel the globe to glimpse alignments of the sun, Earth and moon. Japan's Kaguya probe did them one better: It shot this sequence of a Feb. 10, 2009, eclipse from its lunar orbit. The image shows the view of the sun from the moon mostly covered by Earth. The "ring" appears dark at the bottom because it is obscured by the night-darkened limb of the moon. The Kaguya orbiter was launched in September 2007 to study the moon's origin and evolution. It made a controlled crash landing on the moon in June 2009. (JAXA / NHK) Back to slideshow navigation
  12. 2009: NASA goes back to the moon

    On June 18, 2009, NASA launched two spacecraft to the moon to map its surface in unprecedented detail, scout for future landing sites, and smash probes into a permanently shaded crater in hopes of resolving a longstanding debate over whether such regions contain water ice. NASA's Lunar Reconnaissance Orbiter will orbit both poles for a year, and its mission could be extended to serve as a communications relay for future lunar missions. This is one of the first pictures sent back by the orbiter. LRO's sibling, the crater-smacking LCROSS probe, is due to impact the moon's south pole in October. (NASA / GSFC / ASU) Back to slideshow navigation
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  1. NASA
    Above: Slideshow (12) 50 years of moon shots
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    Slideshow (12) Month in Space: January 2014


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