[meteorite-list] NASA'S Twin GRAIL Spacecraft Reunite In Lunar Orbit

[Ron Baalke]

Jan. 1, 2012

Dwayne Brown 
Headquarters, Washington 
202-358-1726 
dwayne.c.brown at nasa.gov 

DC Agle 
Jet Propulsion Laboratory, Pasadena, Calif. 
818-393-9011 
agle at jpl.nasa.gov 

Caroline McCall 
Massachusetts Institute of Technology, Cambridge 
617-253-1682 
cmcall5 at mit.edu 

RELEASE: 12-001

NASA'S TWIN GRAIL SPACECRAFT REUNITE IN LUNAR ORBIT

PASADENA, Calif. -- 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 and GRAIL-B will study the moon as never before. 

"NASA greets the new year with a new mission of exploration," said 
NASA Administrator Charles Bolden. "The twin GRAIL spacecraft will 
vastly expand our knowledge of our moon and the evolution of our own 
planet. We begin this year reminding people around the world that 
NASA does big, bold things in order to reach for new heights and 
reveal the unknown." 

GRAIL-B achieved lunar orbit at 2:43 p.m. PST (5:43 p.m. EST) today. 
GRAIL-A successfully completed its burn yesterday at 2 p.m. PST (5 
p.m. EST). The insertion maneuvers placed the spacecraft into a 
near-polar, elliptical orbit with an orbital period of approximately 
11.5 hours. Over the coming weeks, the GRAIL team will execute a 
series of burns with each spacecraft to reduce their orbital period 
to just under two hours. At the start of the science phase in March 
2012, the two GRAILs will be in a near-polar, near-circular orbit 
with an altitude of about 34 miles (55 kilometers). 

During GRAIL's science mission, the two spacecraft will transmit radio 
signals precisely defining the distance between them. As they fly 
over areas of greater and lesser gravity caused by visible features 
such as mountains and craters, and masses hidden beneath the lunar 
surface, the distance between the two spacecraft will change 
slightly. 

Scientists will translate this information into a high-resolution map 
of the moon's gravitational field. The data will allow scientists to 
understand what goes on below the lunar surface. This information 
will increase knowledge of how Earth and its rocky neighbors in the 
inner solar system developed into the diverse worlds we see today. 

Each spacecraft carries a small camera called GRAIL MoonKAM (Moon 
Knowledge Acquired by Middle school students) with the sole purpose 
of education and public outreach. 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. 

GRAIL MoonKAM will engage middle schools across the country in the 
GRAIL mission and lunar exploration. Thousands of fifth- to 
eighth-grade students will select target areas on the lunar surface 
and send requests to the GRAIL MoonKAM Mission Operations Center in 
San Diego. Photos of the target areas will be sent back by the GRAIL 
satellites for students to study. 

A student contest that began in October 2011 also will choose new 
names for the spacecraft. The new names are scheduled to be announced 
in January 2012. Ride and Maria Zuber, the mission's principal 
investigator at the Massachusetts Institute of Technology in 
Cambridge, chaired the final round of judging. 

NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the 
GRAIL mission for NASA's Science Mission Directorate, Washington. The 
GRAIL mission is part of the Discovery Program managed at NASA's 
Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin 
Space Systems in Denver built the spacecraft. 

For more information about GRAIL, visit: 

http://www.nasa.gov/grail 

Information about MoonKAM is available online at: 

http://solarsystem.nasa.gov/grail/education.cfm 
	
-end-