Twin Grail spacecraft begin collecting lunar science data

Mar 07, 2012
Artist concept of GRAIL mission. GRAIL will fly twin spacecraft in tandem orbits around the moon to measure its gravity field in unprecedented detail. Image credit: NASA/JPL

(PhysOrg.com) -- NASA's Gravity Recovery And Interior Laboratory (GRAIL) spacecraft orbiting the moon officially have begun their science collection phase. During the next 84 days, scientists will obtain a high-resolution map of the lunar gravitational field to learn about the moon's internal structure and composition in unprecedented detail. The data also will provide a better understanding of how Earth and other rocky planets in the solar system formed and evolved.

"The initiation of is a time when the team lets out a collective sigh of relief because we are finally doing what we came to do," said Maria Zuber, principal investigator for the GRAIL mission at the Massachusetts Institute of Technology in Cambridge. "But it is also a time where we have to put the coffee pot on, roll up our sleeves and get to work."

The GRAIL mission's twin, washing-machine-sized spacecraft, named Ebb and Flow, entered on New Year's Eve and New Years Day. GRAIL's science phase began yesterday at 8:15 p.m. EST (5:15 p.m. PST). During this mission phase, the spacecraft will transmit precisely defining the distance between them. As they fly over areas of greater and lesser gravity caused by visible features such as mountains, craters and masses hidden beneath the lunar surface, the distance between the two spacecraft will change slightly. Science activities are expected to conclude on May 29, after GRAIL maps the of the moon three times.

"We are in a near-polar, near-circular orbit with an average altitude of about 34 miles (55 kilometers) right now," said David Lehman, GRAIL project manager from NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "During the science phase, our spacecraft will orbit the moon as high as 31 miles (51 kilometers) and as low as 10 miles (16 kilometers). They will get as close to each other as 40 miles (65 kilometers) and as far apart as 140 miles (225 kilometers)."

Previously named GRAIL A and B, the names Ebb and Flow were the result of a nation-wide student contest to choose new names for the . The winning entry was submitted by fourth graders from the Emily Dickinson Elementary School in Bozeman, Mont. Nearly 900 classrooms with more than 11,000 students from 45 states, Puerto Rico and the District of Columbia, participated in the contest.

Explore further: Lunar explorers will walk at higher speeds than thought

More information: www.nasa.gov/grail

Related Stories

NASA's GRAIL-A spacecraft 24 hours away from Moon

Dec 31, 2011

(PhysOrg.com) -- NASA's Gravity Recovery And Interior Laboratory (GRAIL)-A spacecraft is within 24 hours of its insertion burn that will place it into lunar orbit. At the time the spacecraft crossed the milestone ...

Twin Grail spacecraft reunite in lunar orbit

Jan 02, 2012

(PhysOrg.com) -- The second of NASA's two Gravity Recovery And Interior Laboratory (GRAIL) spacecraft has successfully completed its planned main engine burn and is now in lunar orbit. Working together, GRAIL-A ...

NASA's moon twins going their own way

Oct 07, 2011

NASA's Gravity Recovery And Interior Laboratory (GRAIL)-B spacecraft successfully executed its first flight path correction maneuver Wednesday, Oct. 5. The rocket burn helped refine the spacecraft's trajectory ...

Recommended for you

Lunar explorers will walk at higher speeds than thought

9 hours ago

Anyone who has seen the movies of Neil Armstrong's first bounding steps on the moon couldn't fail to be intrigued by his unusual walking style. But, contrary to popular belief, the astronaut's peculiar walk ...

Space: The final frontier... open to the public

11 hours ago

Historically, spaceflight has been reserved for the very healthy. Astronauts are selected for their ability to meet the highest physical and psychological standards to prepare them for any unknown challenges. However, with ...

NASA releases IRIS footage of X-class flare (w/ Video)

11 hours ago

On Sept. 10, 2014, NASA's newest solar observatory, the Interface Region Imaging Spectrograph, or IRIS, mission joined other telescopes to witness an X-class flare – an example of one of the strongest solar flares—on ...

NASA's Maven spacecraft reaches Mars this weekend

11 hours ago

Mars, get ready for another visitor or two. This weekend, NASA's Maven spacecraft will reach the red planet following a 10-month journey spanning 442 million miles (711 million kilometers).

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

hyongx
4.5 / 5 (2) Mar 07, 2012
Long-term survival of humanity depends on the establishment of self-sustaining colonies on the moon. A proof-of-principle that our species can continue after Earth has become entirely toxic and too hot.
First, extracting water from the soil and using either fusion or solar energy is essential. Thanks NASA for pioneering this essential investigation.
roboferret
not rated yet Mar 08, 2012
Long-term survival of humanity depends on the establishment of self-sustaining colonies on the moon. A proof-of-principle that our species can continue after Earth has become entirely toxic and too hot.
First, extracting water from the soil and using either fusion or solar energy is essential. Thanks NASA for pioneering this essential investigation.


If even the worst predictions for global warming and pollution come true, the Earth will still be vastly more hospitable than the Moon. The most inhospitable environments on earth are lush oases compared to the most benign environments in our solar system (thus discovered). Bunkers are a more preferable option than a moon-base for anything less than a surface-melting asteroid collision, if the survival of the species are your concern.