Space

May 30, 2012

NASA lunar spacecraft complete prime mission ahead of schedule

An artist’s depiction of the twin spacecraft that comprise NASA’s Gravity Recovery And Interior Laboratory (GRAIL) mission. During the GRAIL mission’s science phase, spacecraft (Ebb and Flow) transmit radio signals precisely defining the distance between them as they orbit the moon in formation. As the two fly over areas of greater and lesser gravity caused by both visible features, such as mountains and craters, and masses hidden beneath the lunar surface, the distance between the two spacecraft will change slightly. Mission scientists use this information to create a high-resolution map of the moon’s gravitational field. The data will allow scientists to understand what goes on below the lunar surface.

A NASA mission to study the moon from crust to core has completed its prime mission earlier than expected.

The mission team of NASA’s Gravity Recovery and Interior Laboratory mission, with twin probes named Ebb and Flow, is now preparing for extended science operations starting Aug. 30 and continuing through Dec. 3, 2012.

The GRAIL mission has gathered unprecedented detail about the internal structure and evolution of the moon. This information will increase our knowledge of how Earth and its rocky neighbors in the inner solar system developed into the diverse worlds we see today.

Since March 8, the spacecraft have operated around the clock for 89 days. From an orbit that passes over the lunar poles, they have collected data covering the entire surface three times. An instrument called the Lunar Gravity Ranging System onboard each spacecraft transmits radio signals that allow scientists to translate the data into a high-resolution map of the moon’s gravitational field. The spacecraft returned their last data set of the prime mission today. The instruments were turned off at 1 p.m., EDT, when the spacecraft were 37 miles above the Sea of Nectar.

“Many of the measurement objectives were achieved from analysis of only half the primary mission data, which speaks volumes about the skill and dedication of our science and engineering teams,” said Maria Zuber, principal investigator of GRAIL at the Massachusetts Institute of Technology in Cambridge. “While there is a great deal of work yet to be done to achieve the mission’s science, it’s energizing to realize that what we traveled from Earth to the moon for is right here in our hands.”

“GRAIL delivered to Earth over 99.99 percent of the data that could have been collected, which underscores the flawless performance of the spacecraft, instrument and the Deep Space Network,” said Zuber.

Both spacecraft instruments will be powered off until Aug. 30. The spacecraft will have to endure a lunar eclipse on June 4. The eclipse and the associated sudden changes in temperature and the energy-sapping darkness that accompanies the phenomena were expected and do not concern engineers about the spacecraft’s health.

“Before launch, we planned for all of GRAIL’s primary mission science to occur between lunar eclipses,” said David Lehman, project manager of GRAIL from NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “But now that we have flown Ebb and Flow for a while, we understand them and are confident they can survive these eclipses in good shape.”

The extended mission goal is to take an even closer look at the moon’s gravity field. To achieve this, GRAIL mission planners will halve their current operating altitude flying at the lowest altitude that can be safely maintained.

“Orbiting at an average altitude of 14 miles during the extended mission, the GRAIL twins will be clearing some of the moon’s higher surface features by about 5 miles (8 kilometers),” said Joe Beerer, GRAIL’s mission manager. “If Ebb and Flow had feet, I think by reflex they’d want to pull them up every time they fly over a mountain.”

Along with mission science, GRAIL’s MoonKAM (Moon Knowledge Acquired by Middle school students) education and public outreach program is also extended. To date over 70,000 student images of the moon have been obtained. The MoonKAM program is led by Sally Ride, America’s first woman in space, and her team at Sally Ride Science in collaboration with undergraduate students at the University of California in San Diego.

The GRAIL mission is managed by JPL for NASA’s Science Mission Directorate in Washington. The mission is part of the Discovery Program managed at NASA’s Marshall Space Flight Center in Huntsville, Ala. NASA’s Deep Space Network is an international network of antennas that supports interplanetary spacecraft missions and radio and radar astronomy observations for the exploration of the solar system and the universe. The network also supports selected Earth-orbiting missions. Lockheed Martin Space Systems in Denver built the spacecraft.




All of this week's top headlines to your email every Friday.


 
 

 

Headlines August 1, 2015

News: Marine F-35 jets deemed ready for combat – A small batch of the highly anticipated – and much criticized – F-35B Joint Strike Fighter jets have been approved for combat by the U.S. Marine Corps.   News: Reports: China to sell J-10 fighter to Iran, Syria? – Iran is rumored external link to be buying 150...
 
 

News Briefs August 3, 2015

Russian military helicopter crashes during air show, one dead A Russian military helicopter crashed Aug. 2 during an aerobatic display, killing one of its crewmembers and injuring another, the Defense Ministry said. The Mi-28 helicopter gunship was part of a flight of helicopters performing aerobatics at the Dubrovichi firing range in Ryazan region, about 170...
 
 
Army photograph by John Andrew Hamilton

Improved Multiple Launch Rocket System tested at White Sands Missile Range

Army photograph by John Andrew Hamilton A Multiple Launch Rocket System with an improved armored cab fires a training rocket during a test. The rockets were simple training rockets and not equipped with a warhead, but still gen...
 

 

Missile Defense Agency, Raytheon demonstrate SM-6’s new anti-ballistic missile defense capability

In a first-of-its-kind test, the U.S. Navy fired a Raytheon Standard Missile-6, intercepting and destroying a short-range ballistic missile target at sea. The successful U.S. Missile Defense Agency test proved a modified SM-6 can eliminate threat ballistic missiles in their final seconds of flight. “SM-6 is the only missile in the world that can do...
 
 

Northrop Grumman-developed stealthy data link validated as combat ready with U.S. Marine Corps

the U.S. Marine Corps achieving F-35B initial operating capability, the Multifunction Advanced Data Link waveform developed by Northrop Grumman has been proven a key combat-ready capability of the F-35 Lightning II program. MADL is a high-data-rate, directional communications link that allows fifth-generation aircraft to communicate and coordinate tactics covertly. During testing of the Lockhee...
 
 

Lockheed Martin technology helps pilots, UAS operators share data, stay safe

As Unmanned Aircraft Systems take to the skies, it is essential for safety that UAS operators and pilots are aware of each other. To help provide this shared situational awareness, Lockheed Martin has deployed the first components of a UAS traffic management system that is available to the UAS community now. Lockheed Martin’s online Flight...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>