Work on the GRAIL project primarily involved the 4 RWA (Reaction Wheel Assemblies) that were to be used on each probe.
My roles involved overseeing the delicate assembly process, and addressing issues that came up during assembly and validation testing. This included schedule updates, test documentation, corrective action creation and execution, as well as all of the required EIDP documentation.
Effective communication was critical in this role, as I frequently needed to work with nearly every department on site. Ultimately we were able to deliver the units on schedule, and the units behaved flawlessly in their mission, a real testament to the team.
An artist’s depiction of the twin spacecraft that comprise NASA’s Gravity Recovery And Interior Laboratory (GRAIL) mission. 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. Image credit: NASA/JPL-Caltech/MIT › Full image and caption
PASADENA, Calif. — A NASA mission to study the moon from crust to core has completed its prime mission earlier than expected. The team of NASA’s Gravity Recovery and Interior Laboratory (GRAIL) 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 10 a.m. PDT (1 p.m. EDT) when the spacecraft were 37 miles (60 kilometers) 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 to the lowest altitude that can be safely maintained.
“Orbiting at an average altitude of 14 miles (23 kilometers) 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 of JPL, 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. JPL is a division of the California Institute of Technology in Pasadena.
For more information about GRAIL, visit:
DC Agle 818-393-9011
Jet Propulsion Laboratory, Pasadena, Calif.
Dwayne Brown 202-358-1726
NASA Headquarters, Washington
Caroline McCall 617-253-1682
Massachusetts Institute of Technology, Cambridge
My work on the Grail Lunar Surveyor sent me traveling to Ithaca New York to work with Goodrich ISR on its completion of the RWAs (Reaction Wheel Assemblies). The work was an exercise in orchestration under pressure, as a launch window was approaching quickly. My role had me involved in many phases of the project, from fabrication and testing, to writing up formal assembly procedures.
(South pole of the far side of the moon as seen from the GRAIL mission’s Ebb spacecraft. Image credit: NASA/JPL-Caltech
PASADENA, Calif. — A camera aboard one of NASA’s twin Gravity Recovery And Interior Laboratory (GRAIL) lunar spacecraft has returned its first unique view of the far side of the moon. MoonKAM, or Moon Knowledge Acquired by Middle school students, will be used by students nationwide to select lunar images for study.
GRAIL consists of two identical spacecraft, recently named Ebb and Flow, each of which is equipped with a MoonKAM. The images were taken as part of a test of Ebb’s MoonKAM on Jan. 19. The GRAIL project plans to test the MoonKAM aboard Flow at a later date.
To view the 30-second video clip, visit: http://go.nasa.gov/zZXAPs .
In the video, the north pole of the moon is visible at the top of the screen as the spacecraft flies toward the lunar south pole. One of the first prominent geological features seen on the lower third of the moon is the Mare Orientale, a 560-mile-wide (900 kilometer) impact basin that straddles both the moon’s near and far side.
The clip ends with rugged terrain just short of the lunar south pole. To the left of center, near the bottom of the screen, is the 93-mile-wide (149 kilometer) Drygalski crater with a distinctive star-shaped formation in the middle. The formation is a central peak, created many billions of years ago by a comet or asteroid impact.
“The quality of the video is excellent and should energize our MoonKAM students as they prepare to explore the moon,” said Maria Zuber, GRAIL principal investigator from the Massachusetts Institute of Technology in Cambridge.
The twin spacecraft successfully achieved lunar orbit this past New Year’s Eve and New Year’s Day. Previously named GRAIL-A and GRAIL-B, the washing machine-sized spacecraft received their new names from fourth graders at the Emily Dickinson Elementary School in Bozeman, Mont., following a nationwide student naming contest.
Thousands of fourth- 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 satellites for students to study. The MoonKAM program is led by Sally Ride, America’s first woman in space. Her team at Sally Ride Science and undergraduate students at the University of California in San Diego will engage middle schools across the country in the GRAIL mission and lunar exploration. GRAIL is NASA’s first planetary mission carrying instruments fully dedicated to education and public outreach.
“We have had great response from schools around the country; more than 2,500 signed up to participate so far,” Ride said. “In mid-March, the first pictures of the moon will be taken by students using MoonKAM. I expect this will excite many students about possible careers in science and engineering.”
Launched in September 2011, Ebb and Flow periodically perform trajectory correction maneuvers that, over time, will lower their orbits to near-circular ones with an altitude of about 34 miles (55 kilometers). During their science mission, the duo will answer longstanding questions about the moon and give scientists a better understanding of how Earth and other rocky planets in the solar system formed.
NASA’s Jet Propulsion Laboratory in Pasadena, Calif., manages the GRAIL mission for NASA’s Science Mission Directorate in 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 at: https://moonkam.ucsd.edu .
JPL is managed for NASA by the California Institute of Technology in Pasadena.