The two spacecraft in the GRAIL mission aim to create a new gravity map of the moon. They will go into orbit one after the other on New Year's Eve and New Year's Day.
NASA's Next Mission: Deep Space
(click image for larger view and for slideshow)
Twin NASA spacecraft are on their final approach to begin orbiting the moon to study its surface and core in the space agency's latest moon-observation mission.
The two Gravity Recovery And Interior Laboratory (GRAIL) crafts will be placed in orbit New Year's Eve and New Year's Day, and will spend two months reshaping their orbits until they are following each other directly, according to NASA.
The agency's Jet Propulsion Laboratory is managing the mission, the goal of which is to use details on the moon's surface to map lunar gravity and use that information to understand better the moon's interior and thermal history, according to NASA.
Together, the spacecraft carry a single instrument that will measure the changes in their relative velocity so scientists can use the information to create a high-resolution map of the moon's gravitational field.
As they fly over areas of greater and lesser gravity--caused by features on and below the moon's surface--they will move slightly toward and away from each other, which will allow scientists to measure gravity through radio signals transmitted by the instrument, called the Ultra Stable Oscillator, according to NASA.
"This mission will rewrite the textbooks on the evolution of the moon," giving new clues about how it and other rocky planets formed, said Maria Zuber, GRAIL principal investigator from the Massachusetts Institute of Technology, in a statement. She added that the spacecraft so far have been operating according to plan and should successfully fulfill their mission.
The mission's gravity-measuring technique is the same as NASA's Gravity Recovery And Climate Experiment (GRACE), which has been mapping Earth's gravity since 2002.
GRAIL-A is scheduled to go into orbit beginning at 1:21 p.m. PST (4:21 p.m. EST) on Dec. 31, and Grail-B is scheduled to do the same at 2:05 p.m. PST (5:05 p.m. EST) on Jan. 1.
Although it is only about 250,000 miles from the earth to the moon--and NASA's Apollo crews took only three days to travel there--the twin GRAIL spacecraft launched from Cape Canaveral Air Force Station Sept. 10 and have covered more than 2.5 million miles to reach the moon, according to NASA.
The reason for the long-duration trajectory was to give NASA time to gauge the health of the crafts and continuously power a core component of the Ultra Stable Oscillator for several months. The length of time allowed it to reach a stable operating temperature before it begins taking measurements, according to NASA.
How 10 federal agencies are tapping the power of cloud computing--without compromising security. Also in the new, all-digital InformationWeek Government supplement: To judge the success of the OMB's IT reform efforts, we need concrete numbers on cost savings and returns. Download our Cloud In Action issue of InformationWeek Government now. (Free registration required.)
The Agile ArchiveWhen it comes to managing data, donít look at backup and archiving systems as burdens and cost centers. A well-designed archive can enhance data protection and restores, ease search and e-discovery efforts, and save money by intelligently moving data from expensive primary storage systems.
2014 Analytics, BI, and Information Management SurveyITís tried for years to simplify data analytics and business intelligence efforts. Have visual analysis tools and Hadoop and NoSQL databases helped? Respondents to our 2014 InformationWeek Analytics, Business Intelligence, and Information Management Survey have a mixed outlook.
Join us for a roundup of the top stories on InformationWeek.com for the week of December 14, 2014. Be here for the show and for the incredible Friday Afternoon Conversation that runs beside the program.