Featured Research

from universities, journals, and other organizations

Rocket burn sets stage for dynamic moon duos' lunar impact

Date:
December 16, 2012
Source:
NASA/Jet Propulsion Laboratory
Summary:
The lunar twins of NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission have each completed a rocket burn that has sealed their fate. The burns modified the orbit of the formation-flying spacecraft. Over the next three days, this new orbit will carry the twins lower and lower over the moon's surface. On Monday afternoon, Dec. 17, at about 2:28 p.m. PST (5:28 p.m. EST), their moon-skimming will conclude when a portion of the lunar surface -- an unnamed mountain near the natural satellite's north pole -- rises higher than their orbital altitude.

An artist's depiction of the GRAIL twins (Ebb and Flow) in lunar orbit. During GRAIL's prime mission science phase, the two spacecraft will orbit the moon as high as 31 miles (51 kilometers) and as low as 10 miles (16 kilometers).
Credit: NASA/Caltech-JPL/MIT

The lunar twins of NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission have each completed a rocket burn that has sealed their fate. The burns modified the orbit of the formation-flying spacecraft. Over the next three days, this new orbit will carry the twins lower and lower over the moon's surface. On Monday afternoon, Dec. 17, at about 2:28 p.m. PST (5:28 p.m. EST), their moon-skimming will conclude when a portion of the lunar surface -- an unnamed mountain near the natural satellite's north pole -- rises higher than their orbital altitude.

The maneuvers began at 7:07 a.m. PST (10:07 a.m. EST) Dec. 14 when the Ebb spacecraft fired its main engines for 55.8 seconds, changing its orbital velocity by 10.3 mph (4.6 meters per second). Sixteen seconds later, still at 7:07 a.m. PST, the Flow spacecraft began its maneuver, executing a burn 55.4 seconds in duration with a resulting change in orbital velocity of 10.3 mph (4.6 meters per second). The spacecraft were named Ebb and Flow by elementary school students in Bozeman, Mont., who won a nationwide contest.

Ebb and Flow are being sent purposely into the lunar surface because their low orbit and low fuel levels preclude further scientific operations.

"NASA wanted to rule out any possibility of our twins hitting the surface anywhere near any of the historic lunar exploration sites like the Apollo landing sites or where the Russian Luna probes touched down," said David Lehman, GRAIL project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Our navigators calculated the odds before this maneuver as about seven in a million. Now, after these two successful rocket firings, there is zero chance."

The unnamed mountain where the two spacecraft will make contact is on the moon's nearside, near its north pole, in the vicinity of a crater named Goldschmidt. Both spacecraft will hit the surface at 3,760 mph (1.7 kilometers per second). No imagery of the impact is expected, because the region will be in shadow at the time.

Both spacecraft have been orbiting the moon since Jan. 1, 2012. The duo's successful primary mission yielded the highest-resolution gravity field map of any celestial body. Future gravity field models developed from data collected during the extended mission will be of even higher resolution. The map will provide a better understanding of how the moon, Earth and other rocky planets in the solar system formed and evolved.

JPL manages the GRAIL mission 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. Lockheed Martin Space Systems in Denver built the spacecraft.

For more information about GRAIL, visit: http://www.nasa.gov/grail


Story Source:

The above story is based on materials provided by NASA/Jet Propulsion Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

NASA/Jet Propulsion Laboratory. "Rocket burn sets stage for dynamic moon duos' lunar impact." ScienceDaily. ScienceDaily, 16 December 2012. <www.sciencedaily.com/releases/2012/12/121216131446.htm>.
NASA/Jet Propulsion Laboratory. (2012, December 16). Rocket burn sets stage for dynamic moon duos' lunar impact. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2012/12/121216131446.htm
NASA/Jet Propulsion Laboratory. "Rocket burn sets stage for dynamic moon duos' lunar impact." ScienceDaily. www.sciencedaily.com/releases/2012/12/121216131446.htm (accessed October 2, 2014).

Share This



More Space & Time News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Astronomers Spot Largest, Brightest Solar Flare Ever

Astronomers Spot Largest, Brightest Solar Flare Ever

Newsy (Oct. 1, 2014) — The initial blast from the record-setting explosion would have appeared more than 10,000 times more powerful than any flare ever recorded. Video provided by Newsy
Powered by NewsLook.com
French Apple Fans Discover the Apple Watch

French Apple Fans Discover the Apple Watch

AFP (Sep. 30, 2014) — Apple fans in France discover the latest toy, the Apple Watch. The watch comes in two sizes and an array of interchangeable, fashionable wrist straps. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
The Water You Drink Might Be Older Than The Sun

The Water You Drink Might Be Older Than The Sun

Newsy (Sep. 27, 2014) — Researchers at the University of Michigan simulated the birth of planets and our sun to determine whether water in the solar system predates the sun. Video provided by Newsy
Powered by NewsLook.com
First Woman Cosmonaut in 17 Years Blasts Off for ISS

First Woman Cosmonaut in 17 Years Blasts Off for ISS

AFP (Sep. 26, 2014) — A Russian Soyuz spacecraft carrying an American astronaut and two Russian cosmonauts, including the first woman cosmonaut in 17 years, blasted off on schedule Friday. Duration: 00:35 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins