Many folks would like to see us back on the Moon and developing its resources.

Sunday, December 18, 2011


I was asked if GRAIL launched and I must admit I had not followed in detail.
What I found and let me know if things change.
- LRK -
Says will but doesn't look current.

Says launched 10 September but will take some time getting to the Moon.
The Gravity Recovery and Interior Laboratory (GRAIL) is an American lunar science mission in NASA's Discovery  Program, which will use high-quality gravitational field mapping of the Moon to determine its interior structure. The two small spacecraft GRAIL A and GRAIL B were launched on 10 September 2011 aboard a single launch vehicle: the most-powerful configuration of a Delta II, the 7920H-10.[1][3][4]
GRAIL A separated from the rocket about nine minutes after launch,
GRAIL B followed about eight minutes later.
They will arrive at their orbits around the Moon 24 hours apart.[5]

The science phase of the mission will last for 90 days. Following the science phase (or extended mission phase), a five-day decommissioning period is planned, after which the spacecraft will impact the lunar surface in about 40 days.[6] The gravity mapping technique is similar to that used by Gravity Recovery and Climate Experiment (GRACE), and the spacecraft design is based on XSS-11.[7]

Unlike the Apollo program missions, which took three days to reach the Moon, GRAIL will make use of a three- to four-month low-energy trans-lunar cruise via the Sun-Earth Lagrange point L1 to reduce fuel requirements, protect instruments and reduce the velocity of the two spacecraft at lunar arrival to help achieve the extremely low 50 km (31 mi) orbits with separation between the spacecraft (arriving 24 hours apart) of 175 to 225 km (109 to 140 mi).[8][9] The very tight tolerances in the flight plan leaves little room for error correction leading to a launch window lasting one second and providing only two launch opportunities per day.[10]

Maria Zuber of the Massachusetts Institute of Technology is GRAIL's principal investigator. The mission's team of expert scientists and engineers also includes former NASA astronaut Sally Ride, who will lead the mission's public outreach efforts. NASA's Jet Propulsion Laboratory manages the project. As of August 5, 2011, the program has cost US$496 million.[11]

Aaah, the NASA GRAIL site with mission elapsed clock.
- LRK -

Spacecraft: GRAIL
Launch Vehicle: United Launch Alliance Delta II Heavy
Launch Site: Cape Canaveral Air Force Station
Launch Pad: Space Launch Complex 17B
Launch Date: Sept. 10, 2011
Launch Time: 9:08:52 a.m. EDT

Twin GRAIL Spacecraft Begin Journey to the Moon Aboard Delta II Rocket

A United Launch Alliance Delta II rocket successfully sent NASA's twin moon-bound GRAIL spacecraft on their way at 9:08 a.m. EDT on Sept. 10, 2011. The launch came during the second window of the day when upper-level winds proved out of limits during the day's first opportunity, just as they had during the first launch attempt on Sept. 8.

The twin spacecraft will study the moon in unprecedented detail.
GRAIL-A is scheduled to reach the moon on New Year's Eve 2011, while GRAIL-B will arrive New Year's Day 2012. The two solar-powered spacecraft will fly in tandem orbits around the moon to measure its gravity field. GRAIL 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.

› GRAIL/Delta II Summary (PDF 650KB)

lunar insertion to be in January 2012
- LRK -

The Gravity Recovery And Interior Laboratory (GRAIL) mission will create the most accurate gravitational map of the moon to date, improving our knowledge of near-side gravity by 100 times and of far-side gravity by 1000 times. The high-resolution gravitational field, especially when combined with a comparable- resolution topographical field, will enable scientists to deduce the moon's interior structure and composition... More >

Key Dates:
Launched: Sept. 10, 2011
Lunar Orbit Insertion: January 2012
Science Mission: March - May 2012

Thanks for looking up with me.
- LRK -

Web Site:
RSS link:
The Gravity Recovery and Interior Laboratory (GRAIL) mission was competitively selected through the Discovery Program. GRAIL launched on a Delta II launch vehicle and will use high-quality gravity field mapping of the moon to determine the moon's interior structure.

GRAIL’s primary science objectives will be to determine the structure of the lunar interior, from crust to core and to advance understanding of the thermal evolution of the Moon. As a secondary objective, GRAIL will extend knowledge gained from the Moon to the other terrestrial planets

Welcome to GRAIL MoonKAM

In 2011, NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission launched twin spacecraft in tandem orbits around the Moon to measure its gravity in unprecedented detail. The mission will answer key questions about the Moon's internal structure and give scientists a better understanding of how our solar system formed.

GRAIL MoonKAM will allow classrooms to request pictures of the lunar surface from cameras on the twin satellites. As we count down to the MoonKAM mission, we will be adding exciting features and resources to
this site, including student activities, teacher guides, and more.




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