NASA NASA s LRO Four Years in Orbit

NASA's Lunar Reconnaissance Orbiter or LRO, in orbit around the moon for four years, has forever changed our view of our nearby neighbor.

LRO launched on an Atlas V rocket on June 18, 2009 from Florida. It took a four day ride to reach its destination and on June 23 successfully entered lunar orbit. In the following four years, LRO has brought the world astounding views of the lunar surface and exciting science results.

"Not only has LRO delivered all the information that is needed for future human and robotic explorers, but it has also revealed that the moon is a more complex and dynamic world than we had ever expected," says Rich Vondrak, LRO deputy project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md.
At the lunar poles the LRO's Diviner instrument has measured the coldest temperatures in the solar system. The Lunar Exploration Neutron Detector has measured how much hydrogen is trapped within the lunar soil. By combining years of this instrument's data, scientists see mounting evidence of hydrogen-rich areas near the moon's poles, suggesting the presence of frozen water. The Mini-RF radar has estimated the maximum amount of ice likely to be found inside a permanently shadowed lunar crater located near the moon's South Pole.

The Lunar Reconnaissance Orbiter Camera has returned high-resolution images of the lunar surface that reveal geological processes and show that the moon is still contracting. This instrument also mapped in high resolution all the Apollo landing sites. The Lunar Orbiter Laser Altimeter has returned data that were used to create the most precise and complete map to date of the altitude variations of the moon's surface.

The CRaTER instrument has measured the radiation environment around the moon and has shown that lighter materials like plastics provide effective shielding against the radiation faced by astronauts during deep-space missions. The Lyman Alpha Mapping Project spectrometer made the first spectroscopic observations of the noble gas helium in the tenuous atmosphere surrounding the moon.

In addition to the great science results from the mission, here are some interesting facts about LRO:

LRO's laser altimeter has conducted over 6 billion topographic measurements
LRO has travelled in lunar orbit over 200 million kilometers, more than the distance to the sun
Produced 434 Terabytes of data that are publicly available through the Planetary Data System
Been in space for 1460 days
Orbited the moon nearly 18,000 times

LRO will continue to send back lunar data until October 2014, with the possibility of an additional two years.

"In its four years in orbit LRO has revealed a new moon with discoveries that address the moon's history and by extension the Earth's history as well," said John Keller, LRO project scientist at NASA Goddard."The innovative measurements by LRO have answered many questions asked by planetary scientists, but have also uncovered new questions as well. I'm looking forward to future work on these new questions as LRO continues to study the moon."

LRO is managed by NASA Goddard for the Science Mission Directorate at NASA Headquarters in Washington.

Nancy Neal Jones
NASA's Goddard Space Flight Center, Greenbelt, Md.