Author Topic: LIVE: NASA - GRAIL Updates  (Read 45767 times)

Offline Chris Bergin

LIVE: NASA - GRAIL Updates
« on: 09/10/2011 09:10 pm »
Continuing coverage of this duo's Lunar mission.

Links of interest (on this site - further posts can link up the NASA sites)

GRAIL Pre-launch processing article - by Chris Gebhardt:
http://www.nasaspaceflight.com/2011/09/twin-grail-satellites-ready-for-nasa-lunar-launch/

GRAIL Launch and Overview - by William Graham:
http://www.nasaspaceflight.com/2011/09/live-ula-deltaii-launch-grail-spacecraft-to-moon/

GRAIL Updates through to S/C Sep:
http://forum.nasaspaceflight.com/index.php?topic=12921.0

L2 Internal Delta II/GRAIL Coverage:
http://forum.nasaspaceflight.com/index.php?topic=26609.0
« Last Edit: 12/17/2012 07:00 pm by Chris Bergin »
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #1 on: 10/03/2011 07:34 pm »
RELEASE: 11-335

NASA INVITES STUDENTS TO NAME MOON-BOUND SPACECRAFT

WASHINGTON -- NASA has a class assignment for U.S. students: help the
agency give the twin spacecraft headed to orbit around the moon new
names.

The naming contest is open to students in kindergarten through 12th
grade at schools in the United States. Entries must be submitted by
teachers using an online entry form. Length of submissions can range
from a short paragraph to a 500-word essay. The entry deadline is
Nov. 11.

NASA's solar-powered Gravity Recovery And Interior Laboratory
(GRAIL)-A and GRAIL-B spacecraft lifted off from Cape Canaveral Air
Force Station, Fla. on Sept. 10 to begin a three-and-a-half-month
journey to the moon. GRAIL will create a gravity map of the moon
using two spacecraft that orbit at very precise distances. The
mission will enable scientists to learn about the moon's internal
structure and composition, and give scientists a better understanding
of its origin. Accurate knowledge of the moon's gravity also could be
used to help choose future landing sites.

"A NASA mission to the moon is one of the reasons why I am a scientist
today," said GRAIL Principal Investigator Maria Zuber from the
Massachusetts Institute of Technology (MIT) in Cambridge. "My hope is
that GRAIL motivates young people today towards careers in science,
math and technology. Getting involved with naming our two GRAIL
spacecraft could inspire their interest not only in space exploration
but in the sciences, and that's a good thing."

Zuber and former astronaut Sally Ride of Sally Ride Science in San
Diego will chair the final round of judging. Sally Ride Science is
the lead for GRAIL's MoonKAM program, which enables students to task
cameras aboard the two GRAIL spacecraft to take close-up views of the
lunar surface.

NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the
GRAIL mission. GRAIL 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 contest rules and more information, visit:


http://grail.nasa.gov/contest


The public can email questions to:


[email protected]


For more information about GRAIL, visit:


http://www.nasa.gov/grail


For more information about MoonKAM, visit:


https://moonkam.ucsd.edu/


Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #2 on: 10/07/2011 03:28 am »
NASA's Moon Twins Going Their Own Way

The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/news.cfm?release=2011-314&cid=release_2011-314

PASADENA, Calif. – NASA's Gravity Recovery And Interior Laboratory (GRAIL)-B spacecraft successfully executed its first flight path correction maneuver Wednesday, Oct. 5. The rocket burn helped refine the spacecraft's trajectory as it travels from Earth to the moon and provides separation between itself and its mirror twin, GRAIL-A. The first burn for GRAIL-A occurred on Sept. 30.

"Both spacecraft are alive and with these burns, prove that they're kicking too, as expected," said David Lehman, GRAIL project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "There is a lot of time and space between now and lunar orbit insertion, but everything is looking good."

GRAIL-B's rocket burn took place on Oct. 5 at 11 a.m. PDT (2 p.m. EDT). The spacecraft's main engine burned for 234 seconds and imparted a velocity change of 56.1 mph (25.1 meters per second) while expending 8.2 pounds (3.7 kilograms) of propellant. GRAIL-A's burn on Sept. 30 also took place at 11 a.m. PDT. It lasted 127 seconds and imparted a 31.3 mph (14 meters per second) velocity change on the spacecraft while expending 4 pounds (1.87 kilograms) of propellant.

These burns are designed to begin distancing GRAIL-A and GRAIL-B's arrival times at the moon by approximately one day and to insert them onto the desired lunar approach paths.

The straight-line distance from Earth to the moon is about 250,000 miles (402,336 kilometers). It took NASA's Apollo moon crews about three days to cover that distance. Each of the GRAIL twins is taking about 30 times that long and covering more than 2.5 million miles (4 million kilometers) to get there. This low-energy, high-cruise time trajectory is beneficial for mission planners and controllers, as it allows more time for spacecraft checkout. The path also provides a vital component of the spacecraft's single science instrument, the Ultra Stable Oscillator, to be continuously powered for several months, allowing it to reach a stable operating temperature long before beginning the collection of science measurements in lunar orbit.

GRAIL-A will enter lunar orbit on New Year's Eve, and GRAIL-B will follow the next day. When science collection begins, the spacecraft will transmit radio signals precisely defining the distance between them as they orbit the moon. Regional gravitational differences on the moon are expected to expand and contract that distance. GRAIL scientists will use these accurate measurements to define the moon's gravity field. The data will allow mission scientists to understand what goes on below the surface of our natural satellite.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the GRAIL mission. The Massachusetts Institute of Technology, Cambridge, is home to the mission's principal investigator, Maria Zuber. The GRAIL mission is part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, built the spacecraft. Launch management for the mission is the responsibility of NASA's Launch Services Program at the Kennedy Space Center in Florida. JPL is a division of the California Institute of Technology in Pasadena.

More information about GRAIL is online at: http://www.nasa.gov/grail and http://grail.nasa.gov .


Offline STS-125

  • Member
  • Posts: 15
  • Germany
    • Raumfahrer.net
  • Liked: 0
  • Likes Given: 0
Re: NASA - GRAIL Updates
« Reply #3 on: 11/27/2011 01:20 am »
On Oct. 23 the two GRAIL Probes had completeted 67.25% of their way to moon. Orbit insertion is scheduled for Dec. 31 (GRAIL-A)/Jan. 1 (GRAIL-B).

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #4 on: 12/23/2011 04:39 pm »
MEDIA ADVISORY: M11-426

NASA TO HOST MEDIA TELECONFERENCE ON PROBES' MOON ORBIT INSERTION



PASADENA, Calif. -- NASA will hold a media teleconference at 11 a.m.
PST on Wednesday, Dec. 28, to preview twin spacecraft being placed in
orbit around the moon on New Year's Eve and New Year's Day.



NASA's twin lunar Gravity Recovery and Interior Laboratory (GRAIL)
probes were launched from Cape Canaveral Air Force Station on Sept.
10, 2011. GRAIL-A is scheduled to arrive in lunar orbit beginning at
1:21 p.m. PST on Saturday, Dec. 31, and GRAIL-B on Sunday, Jan. 1,
beginning at 2:05 p.m. PST. After confirmation they are in orbit and
operating nominally, the two solar-powered spacecraft will fly in
tandem orbits to answer longstanding questions about the moon and
give scientists a better understanding of how Earth and other rocky
planets in the solar system formed.

Participants are:
- Maria Zuber, principal investigator, Massachusetts Institute of
Technology, Cambridge
- David Lehman, project manager, NASA's Jet Propulsion Laboratory
(JPL), Pasadena, Calif.

To participate, reporters must contact the JPL Media Relations Office
at 818-354-5011 by 10:30 a.m. PST on Dec. 28 for the call-in number
and passcode.

Audio of the teleconference will be streamed at:

http://www.nasa.gov/newsaudio



Supporting images will be available 15 minutes prior to the
teleconference at:

http://1.usa.gov/grailnews




For more information about GRAIL visit:

http://www.nasa.gov/grail

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #5 on: 12/28/2011 06:25 pm »
RELEASE: 11-426

NASA TWIN SPACECRAFT ON FINAL APPROACH FOR MOON ORBIT



PASADENA, Calif. -- NASA's twin spacecraft to study the moon from
crust to core are nearing their New Year's Eve and New Year's Day
main-engine burns to place the duo in lunar orbit.

Named Gravity Recovery And Interior Laboratory (GRAIL), the spacecraft
are scheduled to be placed in orbit beginning at 1:21 p.m. PST (4:21
p.m. EST) for GRAIL-A on Dec. 31, and 2:05 p.m. PST (5:05 p.m. EST)
on Jan. 1 for GRAIL-B.

"Our team may not get to partake in a traditional New Year's
celebration, but I expect seeing our two spacecraft safely in lunar
orbit should give us all the excitement and feeling of euphoria
anyone in this line of work would ever need," said David Lehman,
project manager for GRAIL at NASA's Jet Propulsion Laboratory (JPL)
in Pasadena, Calif.

The distance from Earth to the moon is approximately 250,000 miles
(402,336 kilometers). NASA's Apollo crews took about three days to
travel to the moon. Launched from Cape Canaveral Air Force Station
Sept. 10, 2011, the GRAIL spacecraft are taking about 30 times that
long and covering more than 2.5 million miles (4 million kilometers)
to get there.

This low-energy, long-duration trajectory has given mission planners
and controllers more time to assess the spacecraft's health. The path
also allowed a vital component of the spacecraft's single science
instrument, the Ultra Stable Oscillator, to be continuously powered
for several months. This will allow it to reach a stable operating
temperature long before it begins making science measurements in
lunar orbit.

"This mission will rewrite the textbooks on the evolution of the
moon," said Maria Zuber, GRAIL principal investigator from the
Massachusetts Institute of Technology (MIT) in Cambridge. "Our two
spacecraft are operating so well during their journey that we have
performed a full test of our science instrument and confirmed the
performance required to meet our science objectives."

As of Dec. 28, GRAIL-A is 65,860 miles (106,000 kilometers) from the
moon and closing at a speed of 745 mph (1,200 kph). GRAIL-B is 79,540
miles (128,000 kilometers) from the moon and closing at a speed of
763 mph (1,228 kph).

During their final approaches to the moon, both orbiters move toward
it from the south, flying nearly over the lunar south pole. The lunar
orbit insertion burn for GRAIL-A will take approximately 40 minutes
and change the spacecraft's velocity by about 427 mph (688 kph).
GRAIL-B's insertion burn 25 hours later will last about 39 minutes
and is expected to change the probe's velocity by 430 mph (691 kph).

The insertion maneuvers will place each orbiter into a near-polar,
elliptical orbit with a period of 11.5 hours. Over the following
weeks, the GRAIL team will execute a series of burns with each
spacecraft to reduce their orbital period from 11.5 hours down 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).

When science collection begins, the spacecraft will transmit radio
signals precisely defining the distance between them as they orbit
the moon. As they fly over areas of greater and lesser gravity,
caused both by visible features such as mountains and craters and by
masses hidden beneath the lunar surface. they will move slightly
toward and away from each other. An instrument aboard each spacecraft
will measure the changes in their relative velocity very precisely,
and scientists will translate this information into a high-resolution
map of the Moon's gravitational field. The data will allow mission
scientists to understand what goes on below the surface. 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.

JPL manages the GRAIL mission. MIT is home to the mission's principal
investigator, Maria Zuber. 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

Offline dsmillman

  • Member
  • Full Member
  • ****
  • Posts: 1457
  • Liked: 297
  • Likes Given: 14
Re: NASA - GRAIL Updates
« Reply #6 on: 12/29/2011 05:16 pm »
At:

http://www.spaceref.com/news/viewpr.html?pid=35633

there is additional text present in the previous Press Release:

"NOTE TO MEDIA:

Media interested in attending a GRAIL-related function at JPL during the lunar orbit insertion burn of GRAIL-A on Dec. 31 from noon to about 2:30 p.m. PST, must call or email DC Agle at 818-393- 9011 or [email protected] . Those media in attendance will witness a presentation regarding the GRAIL mission and see a closed-circuit television feed of events as they unfold at the nearby GRAIL mission support area. They will also be able to interview GRAIL principal investigator Maria Zuber after successful orbit insertion. While there will be no access to JPL for media on Jan. 1, mission personnel will be available for phone interviews.
"

Hopefully this media event will be streamed.

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #7 on: 12/30/2011 09:52 pm »
News release: 2011-397                                                                    Dec. 30, 2011

NASA's GRAIL-A Spacecraft 24 Hours Away From Moon

The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/news.cfm?release=2011-397&cid=release_2011-397

PASADENA, Calif. -- NASA's Gravity Recovery And Interior Laboratory (GRAIL)-A spacecraft is within 24 hours of its insertion burn that will place it into lunar orbit. At the time the spacecraft crossed the milestone at 1:21 p.m. PST today (4:21 p.m. EST), the spacecraft was 30,758 miles (49,500 kilometers) from the moon.

Launched aboard the same rocket on Sept. 10, 2011, GRAIL-A's mirror twin, GRAIL-B, is also closing the gap between itself and the moon. GRAIL-B is scheduled to perform its lunar orbit insertion burn on New Year's Day (Jan. 1) at 2:05 p.m. PST (5:05 p.m. EST).

As they close in on the moon, both orbiters move toward the moon from the south, flying nearly directly over the lunar south pole. The lunar orbit insertion burn for GRAIL-A will take approximately 40 minutes to complete and change the spacecraft's velocity by about 427 mph (687 kph). GRAIL-B's insertion burn – occurring 25 hours later -- will last about 39 minutes and is expected to change its velocity by 430 mph (692 kph).

The insertion maneuvers will place each orbiter into a near-polar, elliptical orbit with an orbital period of 11.5 hours. Over the following weeks, the GRAIL team will execute a series of burns with each spacecraft to reduce their period down 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 the science phase, the moon will rotate three times underneath the GRAIL orbit. The collection of gravity data over one complete rotation (27.3 days) is referred to as a Mapping Cycle. When science collection begins, the spacecraft will transmit radio signals precisely defining the distance between them as they orbit the moon in formation. Regional gravitational differences on the moon are expected to expand and contract that distance. GRAIL scientists will use these accurate measurements to define the moon's gravity field. The data will allow mission scientists to understand what goes on below the surface of our natural satellite. This information will help us learn more about how the moon, Earth and other terrestrial planets formed.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the GRAIL mission. The Massachusetts Institute of Technology, Cambridge, is home to the mission's principal investigator, Maria Zuber. The GRAIL mission is part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of the California Institute of Technology in Pasadena.



More information about GRAIL is online at: http://www.nasa.gov/grail and http://grail.nasa.gov .

The GRAIL press kit can be found online at: http://www.jpl.nasa.gov/news/press_kits/graiLaunch.pdf .


Offline dsmillman

  • Member
  • Full Member
  • ****
  • Posts: 1457
  • Liked: 297
  • Likes Given: 14
Re: NASA - GRAIL Updates
« Reply #8 on: 12/31/2011 06:53 pm »
You can get a great simulation of Grail by going to:

http://solarsystem.nasa.gov/eyes/

and clicking "Explore Grail"

Offline Space Pete

Re: NASA - GRAIL Updates
« Reply #9 on: 12/31/2011 09:09 pm »
GRAIL-A is now in Lunar orbit.

Congrats! :)
NASASpaceflight ISS Editor

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #10 on: 01/01/2012 10:57 am »
News release: 2011-398                                                                    Dec. 31, 2011

First of NASA's Grail Spacecraft Enters Moon Orbit

The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/news.cfm?release=2011-398&cid=release_2011-398

PASADENA, Calif. – The first of two NASA spacecraft to study the moon in unprecedented detail has entered lunar orbit.

NASA's Gravity Recovery And Interior Laboratory (GRAIL)-A spacecraft successfully completed its planned main engine burn at 2 p.m. PST (5 p.m. EST) today. As of 3 p.m. PST (6 p.m. EST), GRAIL-A is in an orbit of 56 miles by 5,197 miles (90 kilometers by 8,363 kilometers) around the moon that takes approximately 11.5 hours to complete.

"My resolution for the new year is to unlock lunar mysteries and understand how the moon, Earth and other rocky planets evolved," said Maria Zuber, GRAIL principal investigator at the Massachusetts Institute of Technology in Cambridge. "Now, with GRAIL-A successfully placed in orbit around the moon, we are one step closer to achieving that goal."

The next mission milestone occurs tomorrow when GRAIL-A's mirror twin, GRAIL-B, performs its own main engine burn to place it in lunar orbit. At 3 p.m. PST (6 p.m. EST) today, GRAIL-B was 30,018 miles (48,309 kilometers) from the moon and closing at a rate of 896 mph (1,442 kilometers per hour). GRAIL-B's insertion burn is scheduled to begin tomorrow, Jan. 1, at 2:05 p.m. PST (5:05 p.m. EST) and will last about 39 minutes.

"With GRAIL-A in lunar orbit we are halfway home," said David Lehman, GRAIL project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Tomorrow may be New Year's everywhere else, but it's another work day around the moon and here at JPL for the GRAIL team."

Once both spacecraft are confirmed in orbit and operating, science work will begin in March. The spacecraft will transmit radio signals precisely defining the distance between them as they orbit the moon in formation. As they fly over areas of greater and lesser gravity caused by both 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.

JPL manages the GRAIL mission for NASA's Science Mission Directorate at the agency's headquarters 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 .

-end-


Offline Chris Bergin

Re: NASA - GRAIL Updates
« Reply #11 on: 01/01/2012 09:12 pm »
Second GRAIL:

@NASAJPL: And we have main engine burn! #GRAIL-B begins a 38.7 minute burn to be captured into lunar orbit and join #GRAIL-A
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Apollo-phill

  • Full Member
  • ****
  • Posts: 575
  • UK
  • Liked: 192
  • Likes Given: 6
Re: NASA - GRAIL Updates
« Reply #12 on: 01/01/2012 09:44 pm »
Hope GRAIL-B has succesful burn tonight to join its twin already in high lunar orbit

Looking toward March onward when both GRAILs at fairly low perigee and the student Monn KAm camera can start imaging sending back images.

Be following updates this evening - thanks for updates Chris - keep 'em comin and Happy New Year !


A-P

Offline dsmillman

  • Member
  • Full Member
  • ****
  • Posts: 1457
  • Liked: 297
  • Likes Given: 14
Re: NASA - GRAIL Updates
« Reply #13 on: 01/01/2012 09:50 pm »
NASAJPL NASA JPL

Cheers in JPL mission control as everything is looking good for #GRAIL-B. It's going to be a great 2012!!

Offline Chris Bergin

Re: NASA - GRAIL Updates
« Reply #14 on: 01/01/2012 09:51 pm »
One more:

@LockheedMartin Lockheed Martin
Engine shut off. Both #GRAIL spacecraft now in orbit around the moon. Congrats to the team on a great lunar orbit insert & Happy New Year!
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: NASA - GRAIL Updates
« Reply #15 on: 01/01/2012 11:55 pm »
Awesome news! Congrats!

Online jcm

  • Senior Member
  • *****
  • Posts: 3434
  • Jonathan McDowell
  • Somerville, Massachusetts, USA
    • Jonathan's Space Report
  • Liked: 1028
  • Likes Given: 645
Re: NASA - GRAIL Updates
« Reply #16 on: 01/02/2012 12:27 am »
Anyone have actual orbital elements for the capture orbits?
-----------------------------

Jonathan McDowell
http://planet4589.org

Offline Chris Bergin

Re: NASA - GRAIL Updates
« Reply #17 on: 01/02/2012 12:41 am »
Short article, using some of William Graham's content from the launch preview and NASA info.

http://www.nasaspaceflight.com/2012/01/grail-twins-arrive-in-lunar-orbit/
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Online jcm

  • Senior Member
  • *****
  • Posts: 3434
  • Jonathan McDowell
  • Somerville, Massachusetts, USA
    • Jonathan's Space Report
  • Liked: 1028
  • Likes Given: 645
Re: NASA - GRAIL Updates
« Reply #18 on: 01/02/2012 12:50 am »
I found from JPL Horizons some data that appears to be postlaunch but pre-insertion -
planned orbit on Jan 2, GRAIL A in 88 x 8378 km x 87.2 deg, GRAIL B in 111 x 8359 km x 88.3 deg.
-----------------------------

Jonathan McDowell
http://planet4589.org

Offline sdsds

  • Senior Member
  • *****
  • Posts: 6435
  • “With peace and hope for all mankind.”
  • Seattle
  • Liked: 1390
  • Likes Given: 1312
Re: NASA - GRAIL Updates
« Reply #19 on: 01/02/2012 01:37 am »
I found from JPL Horizons some data that appears to be postlaunch but pre-insertion -
planned orbit on Jan 2, GRAIL A in 88 x 8378 km x 87.2 deg, GRAIL B in 111 x 8359 km x 88.3 deg.

That matches the claim in the press release that, "The insertion maneuvers placed the spacecraft into a near-polar, elliptical orbit with an orbital period of approximately 11.5 hours."  (I calculate an 88 x 8378 km lunar orbit has a period of 11.49 hours.)

The March 2012 targets are near-circular orbits with altitudes of about 55 kilometers.  Simplistically that looks like 510 ms/ of delta-v:  dropping the velocity at perilune  from 2135 m/s to 1633 m/s would lower the altitude on the other side of the orbit to 55 km; dropping the velocity there from 1663 ms/ to 1655 m/s then circularizes the orbit.

       (2135 - 1633) + (1663 - 1655) = 510

(The press release claims the periods of those orbits will be "just under two hours."  I calculate 1.89 hours; I guess that's a match?)

Note that e.g. the Apollo 17 CSM while loitering in the mission's 109 x 27 km descent orbit would have experienced the gravity variations GRAIL will measure....
— 𝐬𝐝𝐒𝐝𝐬 —

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #20 on: 01/02/2012 08:35 am »
News release: 2012-001                                                                    Jan. 1, 2012

NASA's Twin Grail Spacecraft Reunite in Lunar Orbit

The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/news.cfm?release=2012-001&cid=release_2012-001

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. JPL is a division of the Çalifornia Institute of Technology in Pasadena.

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


Offline Jason1701

  • Senior Member
  • *****
  • Posts: 2232
  • Liked: 70
  • Likes Given: 144
Re: NASA - GRAIL Updates
« Reply #21 on: 01/02/2012 03:12 pm »
Here's hoping they choose Calvin & Hobbes!

Offline Rocket Science

  • Senior Member
  • *****
  • Posts: 10582
  • NASA Educator Astronaut Candidate Applicant 2002
  • Liked: 4529
  • Likes Given: 13492
Re: NASA - GRAIL Updates
« Reply #22 on: 01/03/2012 12:31 am »
Great way to start off 2012… Happy New Year everyone!  ;D
"The laws of physics are unforgiving"
~Rob: Physics instructor, Aviator

Offline dickgold

  • Member
  • Posts: 18
  • Liked: 0
  • Likes Given: 0
Re: NASA - GRAIL Updates
« Reply #23 on: 01/05/2012 03:14 am »
So when will the new names for the grail spacecrafts
be announced?

My names for the grail spacecrafts would be
Enterprise and Galileo.

Offline TheFallen

  • Full Member
  • ****
  • Posts: 800
  • Liked: 76
  • Likes Given: 159
Re: NASA - GRAIL Updates
« Reply #24 on: 01/05/2012 05:18 am »
Here's hoping they choose Calvin & Hobbes!

Good choices. For some odd reason I'm thinking Starsky & Hutch :P
« Last Edit: 01/05/2012 05:19 am by TheFallen »

Offline HIPAR

  • Member
  • Full Member
  • ****
  • Posts: 585
  • NE Pa (USA)
  • Liked: 1
  • Likes Given: 0
Re: NASA - GRAIL Updates
« Reply #25 on: 01/05/2012 03:38 pm »
Let's hope the mirror image satellites enjoy a harmonious relationship.  If they don't, Lokai and Bele, of Star Trek fame will be appropriate.

But, I suppose that would be too 'dark' for NASA.

---  CHAS
« Last Edit: 01/05/2012 03:40 pm by HIPAR »

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: NASA - GRAIL Updates
« Reply #26 on: 01/05/2012 10:09 pm »
I wouldn't mind a female tag team: Laverne & Shirley  :)

Offline kevin-rf

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8662
  • Overlooking the path Mary's little Lamb took..
  • Liked: 1169
  • Likes Given: 287
Re: NASA - GRAIL Updates
« Reply #27 on: 01/05/2012 11:41 pm »
Pinky and the Brain!
If you're happy and you know it,
It's your med's!

Offline Art LeBrun

  • Photo freak
  • Senior Member
  • *****
  • Posts: 2128
  • Orange, California
  • Liked: 34
  • Likes Given: 0
Re: NASA - GRAIL Updates
« Reply #28 on: 01/05/2012 11:49 pm »
Holmes and Watson........
1958 launch vehicle highlights: Vanguard TV-4 and Atlas 12B

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 14712
  • Liked: 7174
  • Likes Given: 1147
Re: NASA - GRAIL Updates
« Reply #29 on: 01/06/2012 02:23 am »
Holmes and Watson........
Since they went to the Moon in 1989 for a cheese tasting...

Wallace and Gromit!

 - Ed Kyle
« Last Edit: 01/06/2012 02:26 am by edkyle99 »

Offline baldusi

  • Senior Member
  • *****
  • Posts: 8333
  • Buenos Aires, Argentina
  • Liked: 2506
  • Likes Given: 7959
Re: NASA - GRAIL Updates
« Reply #30 on: 01/06/2012 10:58 am »
I wouldn't mind a female tag team: Laverne & Shirley  :)
Thelma & Louise?

Offline dsmillman

  • Member
  • Full Member
  • ****
  • Posts: 1457
  • Liked: 297
  • Likes Given: 14
Re: NASA - GRAIL Updates
« Reply #31 on: 01/08/2012 05:42 pm »
The Grail page at Eyes on the Solar System:

http://solarsystem.nasa.gov/eyes/player/index.html?document=$SERVERURL/content/documents/grail/v1.0/grail.xml

is indicating that the apoapsis of Grail A's orbit has been lowered by more than a thousand miles.  Can anyone confirm this?

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #32 on: 01/12/2012 07:46 pm »
MEDIA ADVISORY: M12-005

NASA AND STUDENTS TO ANNOUNCE NEW NAMES FOR TWIN LUNAR PROBES

WASHINGTON -- NASA will host a news conference at 1 p.m. EST, Tuesday,
Jan. 17, to announce the names selected from a nationwide student
contest for twin spacecraft that will study the moon in unprecedented
detail. The event will be held in the James E. Webb Memorial
Auditorium at NASA Headquarters, located at 300 E Street SW, in
Washington.

Nine hundred schools and more than 11,000 students from 45 states, as
well as Puerto Rico and the District of Columbia, participated in the
contest that began in October 2011.

The agency's twin Gravity Recovery And Interior Laboratory (GRAIL A/B)
spacecraft successfully achieved lunar orbit on New Year's Eve and
New Year's Day, respectively. The status of the spacecraft and
upcoming plans for science operations also will be discussed.

NASA Television and the agency's website will broadcast the live
event. Journalists can participate from NASA centers or join by
phone. To obtain dial-in information, media representatives must
contact Steve Cole at [email protected], by noon EST, Tuesday,
Jan. 17.

The participants are:

-- John Grunsfeld, associate administrator, Science Mission
Directorate, NASA Headquarters, Washington
-- Leland Melvin, associate administrator for Education, NASA
Headquarters
-- Maria Zuber, GRAIL principal investigator, Massachusetts Institute
of Technology, Cambridge, Mass.
-- Sally Ride, president and CEO, Sally Ride Science, San Diego
-- Teacher and students submitting the selected names

The event will be carried live on Ustream, with a live chat box
available, at:

http://www.ustream.tv/nasajpl2

For more information about GRAIL visit:

http://www.nasa.gov/grail

or

http://grail.nasa.gov

For NASA TV streaming video, downlink and schedule information, visit:


http://www.nasa.gov/nasatv

Offline dsmillman

  • Member
  • Full Member
  • ****
  • Posts: 1457
  • Liked: 297
  • Likes Given: 14
Re: NASA - GRAIL Updates
« Reply #33 on: 01/12/2012 08:24 pm »
There was no NASA TV coverage when the Grail Spacecraft went into orbit.  The only news came from the JPL twitter feed.  It makes you wonder who is making the decisions at NASA.

Offline collectSPACE

  • The Source for Space History & Artifacts
  • Full Member
  • ****
  • Posts: 1874
  • Houston, TX
    • collectSPACE
  • Liked: 287
  • Likes Given: 5
Re: NASA - GRAIL Updates
« Reply #34 on: 01/17/2012 05:34 pm »
Students name NASA's twin moon probes 'Ebb' and 'Flow'
http://www.collectspace.com/news/news-011712a.html

NASA's twin, gravity-mapping moon probes received new names Tuesday (Jan. 17), reflecting their mission to study the changing pull of Earth's natural satellite.

Offline Chris Bergin

Re: NASA - GRAIL Updates
« Reply #35 on: 01/17/2012 07:23 pm »
Presser from NASA:

RELEASE: 12-019

MONTANA STUDENTS SUBMIT WINNING NAMES FOR NASA LUNAR SPACECRAFT

WASHINGTON -- Twin NASA spacecraft that achieved orbit around the moon
New Year's Eve and New Year's Day have new names thanks to elementary
students in Bozeman, Montana. Their winning entry, "Ebb and Flow,"
was selected as part of a nation-wide school contest that began in
October 2011.

The names were submitted by fourth graders from the Emily Dickinson
Elementary School. Nearly 900 classrooms with more than 11,000
students from 45 states, Puerto Rico and the District of Columbia,
participated in the contest. Previously named Gravity Recovery And
Interior Laboratory, or GRAIL A and B, the washing machine-sized
spacecraft begin science operations in March.

"The 28 students of Nina DiMauro's class at the Emily Dickinson
Elementary School have really hit the nail on the head," said Maria
Zuber, GRAIL principal investigator from the Massachusetts Institute
of Technology. "We were really impressed that the students drew their
inspiration by researching GRAIL and its goal of measuring gravity.
Ebb and Flow truly capture the spirit and excitement of our mission."

Zuber and Sally Ride, America's first woman in space and CEO of Sally
Ride Science in San Diego, selected the names following the contest,
which attracted 890 proposals via the Internet and mail. The contest
invited ideas from students ages 5 to 18 enrolled in U.S. schools.
Although everything from spelling and grammar to creativity were
considered, Zuber and Ride primarily took into account the quality of
submitted essays.

"With submissions from all over the United States and even some from
abroad, there were a lot of great entries to review," Ride said.
"This contest generated a great deal of excitement in classrooms
across America, and along with it an opportunity to use that
excitement to teach science."

GRAIL is NASA's first planetary mission carrying instruments fully
dedicated to education and public outreach. Each spacecraft carries a
small camera called GRAIL MoonKAM (Moon Knowledge Acquired by Middle
school students). Thousands of students in grades five through eight
will select target areas on the lunar surface and send requests for
study to the GRAIL MoonKAM Mission Operations Center in San Diego.

The winning prize for the Dickinson students is to choose the first
camera images. Dickinson is one of nearly 2,000 schools registered
for the MoonKAM program, which is led by Ride and her team at Sally
Ride Science in collaboration with undergraduate students at the
University of California in San Diego.

"These spacecraft represent not only great science but great
inspiration for our future," said Jim Green, director of NASA's
Planetary Science Division in Washington. "As they study our lunar
neighbor, Ebb and Flow will undergo nearly the same motion as the
tides we feel here on Earth."

Launched in September 2011, Ebb and Flow will be placed in a
near-polar, near-circular orbit 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.

To read the winning submission visit:

https://moonkam.ucsd.edu/about/spacecraft_names

Information about MoonKAM is available online at:

https://moonkam.ucsd.edu

For more information about GRAIL visit:

http://www.nasa.gov/grail

or

http://grail.nasa.gov

Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Jason1701

  • Senior Member
  • *****
  • Posts: 2232
  • Liked: 70
  • Likes Given: 144
Re: NASA - GRAIL Updates
« Reply #36 on: 01/18/2012 03:01 am »
Bozeman? I like it :)

Offline simonbp

  • Science Guy
  • Senior Member
  • *****
  • Posts: 7136
  • Liked: 310
  • Likes Given: 175
Re: NASA - GRAIL Updates
« Reply #37 on: 01/18/2012 02:56 pm »
Aww, I though thought they should have played with the GRAIL theme and gone with Percival and the Beast Glatisant... :)

Offline racshot65

  • Senior Member
  • *****
  • Posts: 2577
  • Aaron Kalair
  • Coventry, England
  • Liked: 0
  • Likes Given: 0
Re: NASA - GRAIL Updates
« Reply #38 on: 02/02/2012 09:39 am »
NASA Mission Returns First Video From Moon's Far Side

http://www.jpl.nasa.gov/news/news.cfm?release=2012-031

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 14712
  • Liked: 7174
  • Likes Given: 1147
Re: NASA - GRAIL Updates
« Reply #39 on: 02/02/2012 02:20 pm »
NASA Mission Returns First Video From Moon's Far Side

http://www.jpl.nasa.gov/news/news.cfm?release=2012-031

Kudos to NASA/JPL/Sally Ride for getting the kids involved with MoonKAM!

(Sally for NASA Admin.  Gets my vote.)

 - Ed Kyle
« Last Edit: 02/02/2012 02:21 pm by edkyle99 »

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #40 on: 03/07/2012 03:26 pm »
RELEASE: 12-070

NASA'S TWIN GRAIL SPACECRAFT BEGIN COLLECTING LUNAR SCIENCE DATA

WASHINGTON -- NASA's Gravity Recovery And Interior Laboratory (GRAIL)
spacecraft orbiting the moon officially have begun their science
collection phase. During the next 84 days, scientists will obtain a
high-resolution map of the lunar gravitational field to learn about
the moon's internal structure and composition in unprecedented
detail. The data also will provide a better understanding of how
Earth and other rocky planets in the solar system formed and evolved.


"The initiation of science data collection is a time when the team
lets out a collective sigh of relief because we are finally doing
what we came to do," said Maria Zuber, principal investigator for the
GRAIL mission at the Massachusetts Institute of Technology in
Cambridge. "But it is also a time where we have to put the coffee pot
on, roll up our sleeves and get to work."

The GRAIL mission's twin, washing-machine-sized spacecraft, named Ebb
and Flow, entered lunar orbit on New Year's Eve and New Years Day.
GRAIL's science phase began yesterday at 8:15 p.m. EST (5:15 p.m.
PST). During this mission phase, the 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, craters and masses hidden beneath the lunar
surface, the distance between the two spacecraft will change
slightly. Science activities are expected to conclude on May 29,
after GRAIL maps the gravity field of the moon three times.

"We are in a near-polar, near-circular orbit with an average altitude
of about 34 miles (55 kilometers) right now," said David Lehman,
GRAIL project manager from NASA's Jet Propulsion Laboratory (JPL) in
Pasadena, Calif. "During the science phase, our spacecraft will orbit
the moon as high as 31 miles (51 kilometers) and as low as 10 miles
(16 kilometers). They will get as close to each other as 40 miles (65
kilometers) and as far apart as 140 miles (225 kilometers)."

Previously named GRAIL A and B, the names Ebb and Flow were the result
of a nation-wide student contest to choose new names for the
spacecraft. The winning entry was submitted by fourth graders from
the Emily Dickinson Elementary School in Bozeman, Mont. Nearly 900
classrooms with more than 11,000 students from 45 states, Puerto Rico
and the District of Columbia, participated in the contest.

JPL 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


Offline racshot65

  • Senior Member
  • *****
  • Posts: 2577
  • Aaron Kalair
  • Coventry, England
  • Liked: 0
  • Likes Given: 0
Re: NASA - GRAIL Updates
« Reply #41 on: 03/23/2012 06:06 pm »
NASA GRAIL Returns First Student-Selected Moon Images

http://www.jpl.nasa.gov/news/news.cfm?release=2012-083

Offline racshot65

  • Senior Member
  • *****
  • Posts: 2577
  • Aaron Kalair
  • Coventry, England
  • Liked: 0
  • Likes Given: 0
Re: NASA - GRAIL Updates
« Reply #42 on: 03/28/2012 03:11 pm »
Flying Formation - Around the Moon at 3,600 MPH

http://www.jpl.nasa.gov/news/news.cfm?release=2012-089

Offline racshot65

  • Senior Member
  • *****
  • Posts: 2577
  • Aaron Kalair
  • Coventry, England
  • Liked: 0
  • Likes Given: 0
Re: NASA - GRAIL Updates
« Reply #43 on: 05/30/2012 12:10 pm »
NASA Lunar Spacecraft Complete Prime Mission Ahead of Schedule

http://www.jpl.nasa.gov/news/news.cfm?release=2012-146

Offline grythumn

  • Full Member
  • **
  • Posts: 243
  • Liked: 164
  • Likes Given: 242
Re: NASA - GRAIL Updates
« Reply #44 on: 08/30/2012 08:28 pm »
Grail is due to start its extended mission today, but no news that I can find. Anyone else have better luck?

-R C

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #45 on: 08/31/2012 06:23 pm »
News release: 2012-273                                                                     Aug. 31, 2012

NASA's GRAIL Moon Twins Begin Extended Mission Science

The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/news.cfm?release=2012-273&cid=release_2012-273

PASADENA, Calif. – NASA's twin, lunar-orbiting Gravity Recovery and Interior Laboratory (GRAIL) spacecraft began data collection for the start of the mission’s extended operations.

At 9:28 a.m. PDT (12:28 p.m. EDT) yesterday, while the two spacecraft were 19 miles (30 kilometers) above the moon’s Ocean of Storms, the Lunar Gravity Ranging System -- the mission's sole science instrument aboard both GRAIL twins -- was energized.

"The data collected during GRAIL's primary mission team are currently being analyzed and hold the promise of producing a gravity field map of extraordinary quality and resolution," said Maria Zuber, principal investigator for GRAIL from the Massachusetts Institute of Technology in Cambridge. "Mapping at a substantially lower altitude during the extended mission, and getting an even more intimate glimpse of our nearest celestial neighbor, provides the unique opportunity to globally map the shallow crust of a planetary body beyond Earth."

The science phase of GRAIL's extended mission runs from Aug. 30 to Dec. 3. Its goals are to take an even closer look at the moon's gravity field, deriving the gravitational influence of surface and subsurface features as small as simple craters, mountains and rilles. To achieve this unprecedented resolution, GRAIL mission planners are halving the operating altitude – flying at the lowest altitude that can be safely maintained.

During the prime mission, which stretched from March 1 to May 29, the two GRAIL spacecraft, named Ebb and Flow, orbited at an average altitude of 34 miles (55 kilometers). The average orbital altitude during extended mission will be 14 miles (23 kilometers), which places the GRAIL twins within five miles (eight kilometers) of some of the moon's higher surface features.

"Ebb and Flow, and our mission operations team, are both doing great, which is certainly notable considering all the milestones and challenges they have experienced," said David Lehman, GRAIL project manager from NASA's Jet Propulsion Laboratory in Pasadena, Calif. "The twins have endured the lunar eclipse of June 4, 2012, and 26 rocket burns since arriving in lunar orbit at the beginning of the year. Down here in our control room, with all the planning and mission operations we have been doing, it feels as though we've been riding right along with them. Of course, they have the better view."

Science data are collected when the Lunar Gravity Ranging System transmit radio signals between the two spacecraft, precisely defining the rate of change of distance between Ebb and Flow. The distance between the twins change slightly as they fly over areas of greater and lesser gravity caused by visible features, such as mountains and craters, and by masses hidden beneath the lunar surface.

Mission scientists calculated that even as the last data were downlinked, four of the mission's six principal science measurement goals had already been achieved. The objective of the GRAIL mission is to generate the most accurate gravity map of the moon and from that derive the internal structure and evolution of Earth's natural satellite.

JPL 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://solarsystem.nasa.gov/grail/

Offline Silmfeanor

  • Full Member
  • ****
  • Posts: 1248
  • Utrecht, The Netherlands
  • Liked: 392
  • Likes Given: 698
Re: NASA - GRAIL Updates
« Reply #46 on: 08/31/2012 08:38 pm »

During the prime mission, which stretched from March 1 to May 29, the two GRAIL spacecraft, named Ebb and Flow, orbited at an average altitude of 34 miles (55 kilometers). The average orbital altitude during extended mission will be 14 miles (23 kilometers), which places the GRAIL twins within five miles (eight kilometers) of some of the moon's higher surface features.


clipping mountains!
I wonder how much delta-V is used per orbit to keep control at such a low altitude with all the changing gravity fields.

Offline spectre9

  • Senior Member
  • *****
  • Posts: 2403
  • Australia
  • Liked: 42
  • Likes Given: 68
Re: NASA - GRAIL Updates
« Reply #47 on: 10/21/2012 07:54 am »
Quote
"The data collected during GRAIL's primary mission team are currently being analyzed and hold the promise of producing a gravity field map of extraordinary quality and resolution," said Maria Zuber, principal investigator for GRAIL from the Massachusetts Institute of Technology in Cambridge.

This has me excited.

With much focus on EML1/2 it's going to be good to have new data on exactly how the gravity of the moon behaves.

There's much unknown about LLO. Just "It's unstable" seems to generalised to me and I'm keen to learn more.

Offline Proponent

  • Senior Member
  • *****
  • Posts: 7097
  • Liked: 2618
  • Likes Given: 1357
Re: NASA - GRAIL Updates
« Reply #48 on: 10/21/2012 02:44 pm »
The further you get from the moon, the better is the approximation that the moon is a spherically-symmetric mass.  Lunar L1 and L2 being about 60,000 km from the moon, I don't think the new information about details of the lunar gravitational field will have much impact on use of the Lagrange points.

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #49 on: 12/05/2012 05:09 pm »
RELEASE: 12-417

NASA TWIN SPACECRAFT CREATE MOST ACCURATE GRAVITY MAP OF MOON

WASHINGTON -- Twin NASA probes orbiting the moon have generated the
highest resolution gravity field map of any celestial body.

The new map, created by the Gravity Recovery and Interior Laboratory
(GRAIL) mission, is allowing scientists to learn about the moon's
internal structure and composition in unprecedented detail. Data from
the two washing machine-sized spacecraft also will provide a better
understanding of how Earth and other rocky planets in the solar
system formed and evolved.

The gravity field map reveals an abundance of features never before
seen in detail, such as tectonic structures, volcanic landforms,
basin rings, crater central peaks, and numerous simple, bowl-shaped
craters. Data also show the moon's gravity field is unlike that of
any terrestrial planet in our solar system.

These are the first scientific results from the prime phase of the
mission, and they are published in three papers in the journal
Science.

"What this map tells us is that more than any other celestial body we
know of, the moon wears its gravity field on its sleeve," said GRAIL
principal investigator Maria Zuber of the Massachusetts Institute of
Technology in Cambridge. "When we see a notable change in the gravity
field, we can sync up this change with surface topography features
such as craters, rilles or mountains."

According to Zuber, the moon's gravity field preserves the record of
impact bombardment that characterized all terrestrial planetary
bodies and reveals evidence for fracturing of the interior extending
to the deep crust and possibly the mantle. This impact record is
preserved, and now precisely measured, on the moon.

The probes revealed the bulk density of the moon's highland crust is
substantially lower than generally assumed. This low bulk crustal
density agrees well with data obtained during the final Apollo lunar
missions in early 1970s, indicating that local samples returned by
astronauts are indicative of global processes.

"With our new crustal bulk density determination, we find that the
average thickness of the moon's crust is between 21 and 27 miles (34
and 43 kilometers), which is about 6 to 12 miles (10 to 20
kilometers) thinner than previously thought." said GRAIL
co-investigator Mark Wieczorek of the Institut de Physique du Globe
de Paris. "With this crustal thickness, the bulk composition of the
moon is similar to that of Earth. This supports models where the moon
is derived from Earth materials that were ejected during a giant
impact event early in solar system history."

The map was created by the spacecraft transmitting radio signals to
define precisely the distance between them as they orbit the moon in
formation. As they fly over areas of greater and lesser gravity
caused by both visible features, such as mountains and craters, and
masses hidden beneath the lunar surface, the distance between the two
spacecraft will change slightly.

"We used gradients of the gravity field in order to highlight smaller
and narrower structures than could be seen in previous datasets,"
said Jeff Andrews-Hanna, a GRAIL guest scientist with the Colorado
School of Mines in Golden. "This data revealed a population of long,
linear, gravity anomalies, with lengths of hundreds of kilometers,
crisscrossing the surface. These linear gravity anomalies indicate
the presence of dikes, or long, thin, vertical bodies of solidified
magma in the subsurface. The dikes are among the oldest features on
the moon, and understanding them will tell us about its early
history."

While results from the primary science mission are just beginning to
be released, the collection of gravity science by the lunar twins
continues. GRAIL's extended mission science phase began Aug. 30 and
will conclude Dec. 17. As the end of mission nears, the spacecraft
will operate at lower orbital altitudes above the moon.

When launched in September 2011, the probes were named GRAIL A and B.
They were renamed Ebb and Flow in January by elementary students in
Bozeman, Mont., in a nationwide contest. Ebb and Flow were placed in
a near-polar, near-circular orbit at an altitude of approximately 34
miles (55 kilometers) on Dec. 31, 2011, and Jan. 1, 2012.

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

To view the lunar gravity map, visit:

http://bit.ly/grailtour

For more information about the mission, visit:

http://www.nasa.gov/grail


Online catdlr

  • Member
  • Senior Member
  • *****
  • Posts: 6837
  • Enthusiast since the Redstones
  • Marina del Rey, California, USA
  • Liked: 3442
  • Likes Given: 2733
Re: NASA - GRAIL Updates
« Reply #50 on: 12/11/2012 01:32 am »
Grail project coming to it's planned end:

MEDIA ADVISORY : M12-238
 
 
NASA to Host Dec.13 Teleconference on Twin Probes Mission Ending Moon Impact

The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/news.php?release=2012-391&cid=release_2012-391 
 
PASADENA, Calif. -- NASA will host a media teleconference at 10:30 a.m. PST (1:30 p.m. EST) Thursday, Dec. 13, to provide an overview of events leading up to twin spacecraft being commanded to impact the moon's surface on Dec. 17 at approximately 2:28 p.m.

NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission, whose two washing machine-sized probes were named Ebb and Flow by elementary school students in Bozeman, Montana, via a nationwide contest, have successfully completed their prime missions and have only days to go on their extended mission science collection. As planned, the duo is running low on fuel. They have been orbiting the moon since New Year's Eve and New Year's Day, respectively, giving scientists unprecedented detail about the moon's internal structure and composition.

For teleconference dial-in information, reporters must send their name, media affiliation and telephone number to Elena Mejia at [email protected] or call NASA's Jet Propulsion Laboratory Media Relations Office at 818-354-5011.

Audio and visuals of the event will be streamed live online at:

http://www.nasa.gov/newsaudio


and


www.ustream.tv/nasajpl


For more information about the mission, visit:

http://www.nasa.gov/grail 

 
- end -
« Last Edit: 12/11/2012 01:34 am by catdlr »
Tony De La Rosa

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #51 on: 12/13/2012 07:53 pm »
RELEASE: 12-434

TWIN NASA PROBES PREPARE FOR DEC. 17 MISSION-ENDING MOON IMPACT

PASADENA, Calif. -- Twin lunar-orbiting NASA spacecraft that have
allowed scientists to learn more about the internal structure and
composition of the moon are being prepared for their controlled
descent and impact on a mountain near the moon's north pole at about
2:28 p.m. PST (5:28 p.m. EST) Monday, Dec. 17.

Ebb and Flow, the Gravity Recovery and Interior Laboratory (GRAIL)
mission probes, are being sent purposely into the lunar surface
because their low orbit and low fuel levels preclude further
scientific operations. The duo's successful prime and extended
science missions generated the highest resolution gravity field map
of any celestial body. The map will provide a better understanding of
how Earth and other rocky planets in the solar system formed and
evolved.

"It is going to be difficult to say goodbye," said GRAIL principal
investigator Maria Zuber of the Massachusetts Institute of Technology
in Cambridge. "Our little robotic twins have been exemplary members
of the GRAIL family, and planetary science has advanced in a major
way because of their contributions."

The mountain where the two spacecraft will make contact is located
near a crater named Goldschmidt. Both spacecraft have been flying in
formation around the moon since Jan. 1, 2012. They were named by
elementary school students in Bozeman, Mont., who won a contest. The
first probe to reach the moon, Ebb, also will be the first to go
down, at 2:28:40 p.m. Flow will follow Ebb about 20 seconds later.

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.

Ebb and Flow will conduct one final experiment before their mission
ends. They will fire their main engines until their propellant tanks
are empty to determine precisely the amount of fuel remaining in
their tanks. This will help NASA engineers validate fuel consumption
computer models to improve predictions of fuel needs for future
missions.

"Our lunar twins may be in the twilight of their operational lives,
but one thing is for sure, they are going down swinging," said GRAIL
project manager David Lehman of NASA's Jet Propulsion Laboratory in
Pasadena, Calif. "Even during the last half of their last orbit, we
are going to do an engineering experiment that could help future
missions operate more efficiently."

Because the exact amount of fuel remaining aboard each spacecraft is
unknown, mission navigators and engineers designed the depletion burn
to allow the probes to descend gradually for several hours and skim
the surface of the moon until the elevated terrain of the target
mountain gets in their way.

The burn that will change the spacecrafts' orbit and ensure the impact
is scheduled to take place Friday morning.

"Such a unique end-of-mission scenario requires extensive and detailed
mission planning and navigation," said Lehman. "We've had our share
of challenges during this mission and always come through in flying
colors, but nobody I know around here has ever flown into a moon
mountain before. It'll be a first for us, that's for sure."

During their prime mission, from March through May, Ebb and Flow
collected data while orbiting at an average altitude of 34 miles (55
kilometers). Their altitude was lowered to 14 miles (23 kilometers)
for their extended mission, which began Aug. 30 and sometimes placed
them within a few miles of the moon's tallest surface features.

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

Offline clongton

  • Expert
  • Senior Member
  • *****
  • Posts: 11609
  • Connecticut
    • Direct Launcher
  • Liked: 6114
  • Likes Given: 2999
Re: NASA - GRAIL Updates
« Reply #52 on: 12/13/2012 11:11 pm »
I wonder what another extended mission might have uncovered, or was the retrieved data about all that could be uniquely identified? Alas - no propellant remains. Adu Ebb and Flow.
Chuck - DIRECT co-founder
I started my career on the Saturn-V F-1A engine

Offline Robert Thompson

  • Full Member
  • ****
  • Posts: 1177
  • Liked: 101
  • Likes Given: 658
Re: NASA - GRAIL Updates
« Reply #53 on: 12/14/2012 04:57 am »
http://target.lroc.asu.edu/da/qmap.html
Sweet toy. The image said 26.63 E but it's west. I'd wish it was impacting further north so we get a northern version of LCROSS.

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: NASA - GRAIL Updates
« Reply #54 on: 12/14/2012 07:25 pm »
MEDIA ADVISORY: M12-240

NASA TO PROVIDE DEC. 17 COMMENTARY AS TWIN PROBES END LUNAR MISSION



PASADENA, Calif. -- NASA will provide live commentary of the scheduled
lunar surface impacts of its twin Gravity Recovery and Interior
Laboratory (GRAIL) spacecraft beginning at 2 p.m. PST (5 p.m. EST)
Monday, Dec. 17. The event will be broadcast on NASA Television and
streamed on the agency's website.

The two probes will hit a mountain near the lunar north pole at
approximately 2:28 p.m. Monday, bringing their successful prime and
extended science missions to an end.

Commentary will originate from the control room at NASA's Jet
Propulsion Laboratory (JPL) in Pasadena, Calif. Coverage will last
about 35 minutes and include live interviews with GRAIL team members.
GRAIL's final resting place on the moon will be in shadow at the time
of impact, so no video documentation of the impacts is expected.

Data from the GRAIL twins are allowing scientists to learn about the
moon's internal structure and composition in unprecedented detail.
The two probes are being sent purposely into the moon because they do
not have enough altitude or fuel to continue science operations.
Media wishing to cover the end of the GRAIL mission at JPL, where they
will have the opportunity to conduct interviews and watch a live feed
from mission control, must contact the JPL Media Relations Office at
818-354-5011 by 11 a.m. Dec. 17. Valid media credentials are
required. Non-U.S. citizens also must present valid passports.

For NASA TV streaming video, schedule and downlink information, visit:



http://www.nasa.gov/ntv

The coverage will also be streamed live on Ustream at:

http://www.ustream.tv/nasajpl2

Join the conversation on Twitter by following the hashtag #GRAIL. To
learn more about all the ways to connect and collaborate with NASA,
visit:

http://www.nasa.gov/connect

For the mission's press kit and other information about GRAIL, visit:

http://www.nasa.gov/grail


Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #55 on: 12/17/2012 07:00 pm »
I think we'll convert this into a live thread for the EOM. I'll convert it back later.
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #56 on: 12/17/2012 08:36 pm »
I think we'll convert this into a live thread for the EOM. I'll convert it back later.

Thanks, I almost forgot!

Time to rush home  :)

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #57 on: 12/17/2012 08:37 pm »
Lockheed Martin ‏@LockheedMartin
Final engine burns on @NASA’s #GRAIL moon orbiters start soon.
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Prober

  • Senior Member
  • *****
  • Posts: 10348
  • Save the spin....I'm keeping you honest!
  • Nevada
  • Liked: 721
  • Likes Given: 729
Re: LIVE: NASA - GRAIL Updates
« Reply #58 on: 12/17/2012 08:50 pm »
kinda a sad ending ......
2017 - Everything Old is New Again.
"I fear all we have done is to awaken a sleeping giant..." --Isoroku Yamamoto

Offline Robert Thompson

  • Full Member
  • ****
  • Posts: 1177
  • Liked: 101
  • Likes Given: 658
Re: LIVE: NASA - GRAIL Updates
« Reply #59 on: 12/17/2012 08:54 pm »
http://www.planetary.org/blogs/emily-lakdawalla/2012/12110923-grail-results.html
Isostasy, gravity, and the Moon: an explainer of the first results of the GRAIL mission, Lakdawalla, 12/11/12

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #60 on: 12/17/2012 09:05 pm »
Live coverage. Not sure if we'll see more than chatting.
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #61 on: 12/17/2012 09:05 pm »
I managed one grab...

expected impact

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #62 on: 12/17/2012 09:06 pm »
23 mins to impact.
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Prober

  • Senior Member
  • *****
  • Posts: 10348
  • Save the spin....I'm keeping you honest!
  • Nevada
  • Liked: 721
  • Likes Given: 729
Re: LIVE: NASA - GRAIL Updates
« Reply #63 on: 12/17/2012 09:08 pm »
Under budget like the sound of that...

2017 - Everything Old is New Again.
"I fear all we have done is to awaken a sleeping giant..." --Isoroku Yamamoto

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #64 on: 12/17/2012 09:08 pm »
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Prober

  • Senior Member
  • *****
  • Posts: 10348
  • Save the spin....I'm keeping you honest!
  • Nevada
  • Liked: 721
  • Likes Given: 729
Re: LIVE: NASA - GRAIL Updates
« Reply #65 on: 12/17/2012 09:10 pm »
2017 - Everything Old is New Again.
"I fear all we have done is to awaken a sleeping giant..." --Isoroku Yamamoto

Offline belegor

  • Full Member
  • ***
  • Posts: 322
  • Switzerland
  • Liked: 13
  • Likes Given: 67
Re: LIVE: NASA - GRAIL Updates
« Reply #66 on: 12/17/2012 09:10 pm »
What's interesting is that there's a large discrepancy between the view shown in the simulation during the broadcast (Ebb & Flow being very close together) and what's shown on Eyes on the Solar System (Ebb & Flow being > 1600 miles apart).

Obviously one of them is off, but which one? (My guess is the simulation during the broadcast is correct, but I don't know..)

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #67 on: 12/17/2012 09:10 pm »

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #68 on: 12/17/2012 09:10 pm »

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #69 on: 12/17/2012 09:10 pm »

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #70 on: 12/17/2012 09:12 pm »
« Last Edit: 12/17/2012 09:13 pm by robertross »

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #71 on: 12/17/2012 09:14 pm »

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #72 on: 12/17/2012 09:16 pm »

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #73 on: 12/17/2012 09:17 pm »
Here's a heart-felt memory...

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #74 on: 12/17/2012 09:17 pm »

Offline Robert Thompson

  • Full Member
  • ****
  • Posts: 1177
  • Liked: 101
  • Likes Given: 658
Re: LIVE: NASA - GRAIL Updates
« Reply #75 on: 12/17/2012 09:17 pm »

Offline Prober

  • Senior Member
  • *****
  • Posts: 10348
  • Save the spin....I'm keeping you honest!
  • Nevada
  • Liked: 721
  • Likes Given: 729
Re: LIVE: NASA - GRAIL Updates
« Reply #76 on: 12/17/2012 09:18 pm »
Now maybe we can find a good site for Moon base Alpha.  Let's get on with it.

2017 - Everything Old is New Again.
"I fear all we have done is to awaken a sleeping giant..." --Isoroku Yamamoto

Offline Robert Thompson

  • Full Member
  • ****
  • Posts: 1177
  • Liked: 101
  • Likes Given: 658
Re: LIVE: NASA - GRAIL Updates
« Reply #77 on: 12/17/2012 09:21 pm »
LM: Flying low enough in basins that they were below mountain level; had to maneuver up to leave basin.

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #78 on: 12/17/2012 09:21 pm »
Traditional dress
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #79 on: 12/17/2012 09:22 pm »

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #80 on: 12/17/2012 09:22 pm »

Online Lee Jay

  • Elite Veteran
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8012
  • Liked: 2949
  • Likes Given: 278
Re: LIVE: NASA - GRAIL Updates
« Reply #81 on: 12/17/2012 09:22 pm »
http://www.planetary.org/blogs/emily-lakdawalla/2012/12110923-grail-results.html
Isostasy, gravity, and the Moon: an explainer of the first results of the GRAIL mission, Lakdawalla, 12/11/12

That was a great article!

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #82 on: 12/17/2012 09:23 pm »
Burned a little longer than thought, due to remaining fuel in the tanks
4 min burn Grail A (EBB)
« Last Edit: 12/17/2012 09:24 pm by robertross »

Offline Prober

  • Senior Member
  • *****
  • Posts: 10348
  • Save the spin....I'm keeping you honest!
  • Nevada
  • Liked: 721
  • Likes Given: 729
Re: LIVE: NASA - GRAIL Updates
« Reply #83 on: 12/17/2012 09:23 pm »
« Last Edit: 12/17/2012 09:24 pm by Prober »
2017 - Everything Old is New Again.
"I fear all we have done is to awaken a sleeping giant..." --Isoroku Yamamoto

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #84 on: 12/17/2012 09:24 pm »

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #85 on: 12/17/2012 09:24 pm »
Nice graphic.

T-5 mins.
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Prober

  • Senior Member
  • *****
  • Posts: 10348
  • Save the spin....I'm keeping you honest!
  • Nevada
  • Liked: 721
  • Likes Given: 729
Re: LIVE: NASA - GRAIL Updates
« Reply #86 on: 12/17/2012 09:25 pm »
Hold your seats 5 min. from first crash.
2017 - Everything Old is New Again.
"I fear all we have done is to awaken a sleeping giant..." --Isoroku Yamamoto

Offline Robert Thompson

  • Full Member
  • ****
  • Posts: 1177
  • Liked: 101
  • Likes Given: 658
Re: LIVE: NASA - GRAIL Updates
« Reply #87 on: 12/17/2012 09:25 pm »
Burned a little longer than thought, due to remaining fuel in the tanks
4 min burn Grail A (EBB)

Could someone convert this into remaining mission capability, provided budget?

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #88 on: 12/17/2012 09:25 pm »
Tracking from Goldstone
« Last Edit: 12/17/2012 09:26 pm by robertross »

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #89 on: 12/17/2012 09:25 pm »
T-3 mins for GRAIL A.
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #90 on: 12/17/2012 09:26 pm »
Here they go...
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Robert Thompson

  • Full Member
  • ****
  • Posts: 1177
  • Liked: 101
  • Likes Given: 658
Re: LIVE: NASA - GRAIL Updates
« Reply #91 on: 12/17/2012 09:27 pm »
I hope they don't wake up the Transformers. It's not the 21st yet, and you never know...

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #92 on: 12/17/2012 09:27 pm »
« Last Edit: 12/17/2012 09:27 pm by robertross »

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #93 on: 12/17/2012 09:27 pm »
Got to sneak over that first ridge.
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #94 on: 12/17/2012 09:28 pm »
1 min 20 sec

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #95 on: 12/17/2012 09:28 pm »
Over the ridge.
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #96 on: 12/17/2012 09:28 pm »
over the ridge..

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #97 on: 12/17/2012 09:28 pm »
20 sec

on target

Offline Prober

  • Senior Member
  • *****
  • Posts: 10348
  • Save the spin....I'm keeping you honest!
  • Nevada
  • Liked: 721
  • Likes Given: 729
Re: LIVE: NASA - GRAIL Updates
« Reply #98 on: 12/17/2012 09:29 pm »
snif, snif both gone...
2017 - Everything Old is New Again.
"I fear all we have done is to awaken a sleeping giant..." --Isoroku Yamamoto

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #99 on: 12/17/2012 09:30 pm »
GRAIL A and B impact.
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #100 on: 12/17/2012 09:30 pm »
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Online Lee Jay

  • Elite Veteran
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 8012
  • Liked: 2949
  • Likes Given: 278
Re: LIVE: NASA - GRAIL Updates
« Reply #101 on: 12/17/2012 09:30 pm »
Great mission.  Congrats to all involved.

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #102 on: 12/17/2012 09:30 pm »

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #103 on: 12/17/2012 09:31 pm »

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #104 on: 12/17/2012 09:31 pm »
Naming the impact area after Sally Ride.
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #105 on: 12/17/2012 09:31 pm »
Final Impact site named after Sally Ride!!
« Last Edit: 12/17/2012 09:32 pm by robertross »

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #106 on: 12/17/2012 09:33 pm »
"Ebb & Flow removed a veil from the moon"

Offline spectre9

  • Senior Member
  • *****
  • Posts: 2403
  • Australia
  • Liked: 42
  • Likes Given: 68
Re: LIVE: NASA - GRAIL Updates
« Reply #107 on: 12/17/2012 09:34 pm »
Really enjoying the gravity maps.  ;D

Great mission and very capable little spacecraft for their size.

Ebb & Flow will be missed.  :(

Thanks for the live coverage guys.

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17934
  • Westphal, Nova Scotia
  • Liked: 648
  • Likes Given: 7354
Re: LIVE: NASA - GRAIL Updates
« Reply #108 on: 12/17/2012 09:35 pm »
And that's it!

Congrats to the teams on a great mission, getting over those hurdles at the end, and making final impact.

Offline Robert Thompson

  • Full Member
  • ****
  • Posts: 1177
  • Liked: 101
  • Likes Given: 658
Re: LIVE: NASA - GRAIL Updates
« Reply #109 on: 12/17/2012 09:35 pm »
http://en.wikipedia.org/wiki/Lunar_craters_named_for_space_explorers
Lunar craters named for space explorers

http://nasawatch.com/archives/2011/02/lunar-craters-p.html
Lunar Craters (Provisionally) Named for Columbia Astronauts

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
Re: LIVE: NASA - GRAIL Updates
« Reply #110 on: 12/17/2012 10:21 pm »
RELEASE: 12-438

NASA'S GRAIL LUNAR IMPACT SITE NAMED FOR ASTRONAUT SALLY RIDE

PASADENA, Calif. -- NASA has named the site where twin agency
spacecraft impacted the moon Monday in honor of the late astronaut,
Sally K. Ride, who was America's first woman in space and a member of
the probes' mission team.

Last Friday, Ebb and Flow, the two spacecraft comprising NASA's
Gravity Recovery and Interior Laboratory (GRAIL) mission, were
commanded to descend into a lower orbit that would result in an
impact Monday on a mountain near the moon's north pole. The
formation-flying duo hit the lunar surface as planned at 2:28:51 p.m.
PST (5:28:51 p.m. EST) and 2:29:21 p.m. PST (5:29:21 p.m. EST) at a
speed of 3,760 mph (1.7 kilometers per second). The location of the
Sally K. Ride Impact Site is on the southern face of an approximately
1.5 mile- (2.5 -kilometer) tall mountain near a crater named
Goldschmidt.

"Sally was all about getting the job done, whether it be in exploring
space, inspiring the next generation, or helping make the GRAIL
mission the resounding success it is today," said GRAIL principal
investigator Maria Zuber of the Massachusetts Institute of Technology
in Cambridge. "As we complete our lunar mission, we are proud we can
honor Sally Ride's contributions by naming this corner of the moon
after her."

The impact marked a successful end to the GRAIL mission, which was
NASA's first planetary mission to carry cameras fully dedicated to
education and public outreach. Ride, who died in July after a
17-month battle with pancreatic cancer, led GRAIL's MoonKAM (Moon
Knowledge Acquired by Middle School Students) Program through her
company, Sally Ride Science, in San Diego.

Along with its primary science instrument, each spacecraft carried a
MoonKAM camera that took more than 115,000 total images of the lunar
surface. Imaging targets were proposed by middle school students from
across the country and the resulting images returned for them to
study. The names of the spacecraft were selected by Ride and the
mission team from student submissions in a nationwide contest.

"Sally Ride worked tirelessly throughout her life to remind all of us,
especially girls, to keep questioning and learning," said Sen.
Barbara Mikulski of Maryland. "Today her passion for making students
part of NASA's science is honored by naming the impact site for her."


Fifty minutes prior to impact, the spacecraft fired their engines
until the propellant was depleted. The maneuver was designed to
determine precisely the amount of fuel remaining in the tanks. This
will help NASA engineers validate computer models to improve
predictions of fuel needs for future missions.

"Ebb fired its engines for 4 minutes, 3 seconds and Flow fired its for
5 minutes, 7 seconds," said GRAIL project manager David Lehman of
NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "It was
one final important set of data from a mission that was filled with
great science and engineering data."

The mission team deduced that much of the material aboard each
spacecraft was broken up in the energy released during the impacts.
Most of what remained probably is buried in shallow craters. The
craters' size may be determined when NASA's Lunar Reconnaissance
Orbiter returns images of the area in several weeks.

Launched in September 2011, Ebb and Flow had been orbiting the moon
since Jan. 1, 2012. The probes intentionally were sent into the lunar
surface because they did not have sufficient altitude or fuel to
continue science operations. Their successful prime and extended
science missions generated the highest resolution gravity field map
of any celestial body. The map will provide a better understanding of
how Earth and other rocky planets in the solar system formed and
evolved.

"We will miss our lunar twins, but the scientists tell me it will take
years to analyze all the great data they got, and that is why we came
to the moon in the first place," Lehman said. "So long, Ebb and Flow,
and we thank you."

JPL manages the GRAIL mission for NASA's Science Mission Directorate
in Washington. GRAIL 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

Offline Chris Bergin

Re: LIVE: NASA - GRAIL Updates
« Reply #111 on: 12/17/2012 10:35 pm »
Our article on it, using some of William Graham's spacecraft overview:

http://www.nasaspaceflight.com/2012/12/grail-mission-ends-with-lunar-impact-and-the-honoring-of-a-hero/
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Rocket Science

  • Senior Member
  • *****
  • Posts: 10582
  • NASA Educator Astronaut Candidate Applicant 2002
  • Liked: 4529
  • Likes Given: 13492
Re: LIVE: NASA - GRAIL Updates
« Reply #112 on: 12/17/2012 10:37 pm »
Here's a heart-felt memory...
This is what schools are meant to be about... God bless the victims of Sandy Hook...
"The laws of physics are unforgiving"
~Rob: Physics instructor, Aviator

Offline mdo

  • Full Member
  • *
  • Posts: 172
  • Liked: 5
  • Likes Given: 3
Re: LIVE: NASA - GRAIL Updates
« Reply #113 on: 12/18/2012 08:35 am »
http://www.planetary.org/blogs/emily-lakdawalla/2012/12110923-grail-results.html
Isostasy, gravity, and the Moon: an explainer of the first results of the GRAIL mission, Lakdawalla, 12/11/12

That was a great article!

An extraordinary primer for a demanding subject - thanks for posting.

Offline Robert Thompson

  • Full Member
  • ****
  • Posts: 1177
  • Liked: 101
  • Likes Given: 658

Offline hyper_snyper

  • Elite Veteran
  • Full Member
  • ****
  • Posts: 728
  • Liked: 1
  • Likes Given: 22

Online catdlr

  • Member
  • Senior Member
  • *****
  • Posts: 6837
  • Enthusiast since the Redstones
  • Marina del Rey, California, USA
  • Liked: 3442
  • Likes Given: 2733
Re: LIVE: NASA - GRAIL Updates
« Reply #116 on: 03/19/2013 06:22 pm »
News feature: 2013-103                                                                       March 19, 2013

Lunar Reconnaissance Orbiter Sees GRAIL's Explosive Farewell

 

The full version of this story with accompanying images is at:
http://www.jpl.nasa.gov/news/news.php?release=2013-103&cid=release_2013-103

Many spacecraft just fade away, drifting silently through space after their mission is over, but not GRAIL. NASA's twin GRAIL (Gravity Recovery and Interior Laboratory) spacecraft went out in a blaze of glory on Dec. 17, 2012, when they were intentionally crashed into a mountain near the moon's north pole.

The successful mission to study the moon's interior took the plunge to get one last bit of science: with the spacecraft kicking up a cloud of dust and gas with each impact, researchers hoped to discover more about the moon's composition. However, with the moon about 380,000 kilometers (over 236,000 miles) away from Earth, the impact plumes would be difficult to observe from here. Fortunately, GRAIL had company. NASA's Lunar Reconnaissance Orbiter (LRO) is orbiting the moon as well, busily making high-resolution maps of the lunar surface. With just three weeks notice, the LRO team scrambled to get their orbiter in the right place at the right time to witness GRAIL's fiery finale.

"We were informed by the GRAIL team about three weeks prior to the impact exactly where the impact site would be," said LRO Project Scientist John Keller of NASA's Goddard Space Flight Center in Greenbelt, Md. "The GRAIL team's focus was on obtaining the highest-resolution gravity measurements possible from the last few orbits of the GRAIL spacecraft, which led to uncertainty in the ultimate impact site until relatively late."

LRO was only about 100 miles (160 kilometers) from the lunar surface at the time of the impact, and variations in gravity from massive features like lunar mountains tugged on the spacecraft, altering its orbit.

The site was in shadow at the time of the impact, so the LRO team had to wait until the plumes rose high enough to be in sunlight before making the observation. The Lyman Alpha Mapping Project (LAMP), an ultraviolet imaging spectrograph on board the spacecraft, saw mercury and enhancements of atomic hydrogen in the plume.

"The mercury observation is consistent with what the LRO team saw from the LCROSS impact in October 2009," said Keller. "LCROSS (Lunar CRater Observation and Sensing Satellite) saw significant amounts of mercury, but the LCROSS site was at the bottom of the moon's Cabeus crater, which hasn't seen sunlight for more than a billion years and is therefore extremely cold."

LRO's Lunar Reconnaissance Orbiter Camera was able to make an image of the craters from the GRAIL impacts despite their relatively small size.

The two spacecraft were relatively small -- cubes about the size of a washing machine with a mass of about 200 kilograms (440 pounds) each at the time of impact. The spacecraft were traveling about 3,800 mph (6,100 kilometers per hour) when they hit the surface.

"Both craters are relatively small, perhaps 4 to 6 meters (about 13 to 20 feet) in diameter and both have faint, dark, ejecta patterns, which is unusual," said Mark Robinson, LROC principal investigator at Arizona State University's School of Earth and Space Sciences, Tempe, Ariz. "Fresh impact craters on the moon are typically bright, but these may be dark due to spacecraft material being mixed with the ejecta."

"Both impact sites lie on the southern slope of an unnamed massif [mountain] that lies south of the crater Mouchez and northeast of the crater Philolaus," said Robinson. "The massif stands as much as 2,500 meters [about 8,202 feet] above the surrounding plains. The impact sites are at an elevation of about 700 meters [around 2,296 feet] and 1,000 meters [3,281 feet], respectively, about 500 to 800 meters [approximately 1,640 to 2,625 feet] below the summit. The two impact craters are about 2,200 meters [roughly 7,218 feet] apart. GRAIL B [renamed Flow] impacted about 30 seconds after GRAIL A [Ebb] at a site to the west and north of GRAIL A."

Lunar Reconnaissance Orbiter complemented the GRAIL mission in other ways as well. LRO's Diviner lunar radiometer observed the impact site and confirmed that the amount of heating of the surface there by the relatively small GRAIL spacecraft was within expectations. LRO's Lunar Orbiter Laser Altimeter (LOLA) instrument bounced laser pulses off the surface to build up a precise map of the lunar terrain, including the three-dimensional structure of features like mountains and craters.

"Combining the LRO LOLA topography map with GRAIL's gravity map yields some very interesting results," said Keller. "You expect that areas with mountains will have a little stronger gravity, while features like craters will have a little less. However, when you subtract out the topography, you get another map that reveals gravity differences that are not tied to the surface. It gives insight into structures deeper in the moon's interior."

JPL manages the GRAIL mission for NASA's Science Mission Directorate in Washington. GRAIL 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 the mission's press kit and other information about GRAIL, visit: http://www.nasa.gov/grail . You can follow JPL News on Facebook at: http://www.facebook.com/nasajpl and on Twitter at: http://www.twitter.com/nasajpl .

The research was funded by the LRO mission, currently under NASA's Science Mission Directorate at NASA Headquarters in Washington. LRO is managed by NASA's Goddard Space Flight Center in Greenbelt, Md.

Images are posted at: http://www.nasa.gov/mission_pages/LRO/news/grail-results.html

DC Agle (818) 393-9011
Jet Propulsion Laboratory, Pasadena, Calif.
[email protected]
- end -


<Click on the picture below to see the before and after.>
« Last Edit: 03/19/2013 06:24 pm by catdlr »
Tony De La Rosa

Online catdlr

  • Member
  • Senior Member
  • *****
  • Posts: 6837
  • Enthusiast since the Redstones
  • Marina del Rey, California, USA
  • Liked: 3442
  • Likes Given: 2733
Re: LIVE: NASA - GRAIL Updates
« Reply #117 on: 03/20/2013 02:32 pm »
2012 Dec 19: GRAIL MoonKAM Final Video (Camera 2)

by: RocketCamByEcliptic

« Last Edit: 03/20/2013 02:33 pm by catdlr »
Tony De La Rosa

Online catdlr

  • Member
  • Senior Member
  • *****
  • Posts: 6837
  • Enthusiast since the Redstones
  • Marina del Rey, California, USA
  • Liked: 3442
  • Likes Given: 2733
Re: LIVE: NASA - GRAIL Updates
« Reply #118 on: 03/20/2013 02:33 pm »
2012 Dec 19: GRAIL MoonKAM Final Video (Camera 3)

by: RocketCamByEcliptic

Tony De La Rosa

Online catdlr

  • Member
  • Senior Member
  • *****
  • Posts: 6837
  • Enthusiast since the Redstones
  • Marina del Rey, California, USA
  • Liked: 3442
  • Likes Given: 2733
Re: LIVE: NASA - GRAIL Updates
« Reply #119 on: 05/30/2013 09:43 pm »
May 30, 2013
 
RELEASE : 13-164
 
 
NASA's Grail Mission Solves Mystery of Moon's Surface Gravity
 
 
PASADENA, Calif. -- NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission has uncovered the origin of massive invisible regions that make the moon's gravity uneven, a phenomenon that affects the operations of lunar-orbiting spacecraft.

Because of GRAIL's findings, spacecraft on missions to other celestial bodies can navigate with greater precision in the future.
GRAIL's twin spacecraft studied the internal structure and composition of the moon in unprecedented detail for nine months. They pinpointed the locations of large, dense regions called mass concentrations, or mascons, which are characterized by strong gravitational pull. Mascons lurk beneath the lunar surface and cannot be seen by normal optical cameras.

GRAIL scientists found the mascons by combining the gravity data from GRAIL with sophisticated computer models of large asteroid impacts and known detail about the geologic evolution of the impact craters. The findings are published in the May 30 edition of the journal Science.

"GRAIL data confirm that lunar mascons were generated when large asteroids or comets impacted the ancient moon, when its interior was much hotter than it is now," said Jay Melosh, a GRAIL co-investigator at Purdue University in West Lafayette, Ind., and lead author of the paper. "We believe the data from GRAIL show how the moon's light crust and dense mantle combined with the shock of a large impact to create the distinctive pattern of density anomalies that we recognize as mascons."

The origin of lunar mascons has been a mystery in planetary science since their discovery in 1968 by a team at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. Researchers generally agree mascons resulted from ancient impacts billions of years ago. It was not clear until now how much of the unseen excess mass resulted from lava filling the crater or iron-rich mantle upwelling to the crust.

On a map of the moon's gravity field, a mascon appears in a target pattern. The bulls-eye has a gravity surplus. It is surrounded by a ring with a gravity deficit. A ring with a gravity surplus surrounds the bulls-eye and the inner ring. This pattern arises as a natural consequence of crater excavation, collapse and cooling following an impact. The increase in density and gravitational pull at a mascon's bulls-eye is caused by lunar material melted from the heat of a long-ago asteroid impact.

"Knowing about mascons means we finally are beginning to understand the geologic consequences of large impacts," Melosh said. "Our planet suffered similar impacts in its distant past, and understanding mascons may teach us more about the ancient Earth, perhaps about how plate tectonics got started and what created the first ore deposits."

This new understanding of lunar mascons also is expected to influence planetary geology well beyond that of Earth and our nearest celestial neighbor.

"Mascons also have been identified in association with impact basins on Mars and Mercury," said GRAIL principal investigator Maria Zuber of the Massachusetts Institute of Technology in Cambridge. "Understanding them on the moon tells us how the largest impacts modified early planetary crusts."

Launched as GRAIL A and GRAIL B in September 2011, the probes, renamed Ebb and Flow, operated in a nearly circular orbit near the poles of the moon at an altitude of about 34 miles (55 kilometers) until their mission ended in December 2012. The distance between the twin probes changed slightly as they flew over areas of greater and lesser gravity caused by visible features, such as mountains and craters, and by masses hidden beneath the lunar surface.

JPL managed GRAIL for NASA's Science Mission Directorate in Washington. The mission was part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. NASA's Goddard Space Flight Center, in Greenbelt, Md., manages the Lunar Reconnaissance Orbiter. Operations of the spacecraft's laser altimeter, which provided supporting data used in this investigation, is led by the Massachusetts Institute of Technology in Cambridge.

Lockheed Martin Space Systems in Denver built GRAIL.

For more information about GRAIL, visit:

http://www.nasa.gov/grail

 
- end -
« Last Edit: 05/30/2013 09:47 pm by catdlr »
Tony De La Rosa

Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 21400
  • Houten, The Netherlands
  • Liked: 7840
  • Likes Given: 312
NASA - GRAIL Updates
« Reply #120 on: 11/09/2013 10:56 am »
NASA's GRAIL Mission Puts a New Face on the Moon

Scientists using data from NASA's Gravity Recovery and Interior Laboratory mission are gaining new insight into how the face of the moon received its rugged good looks.

http://www.jpl.nasa.gov/news/news.php?release=2013-322&utm_source=iContact&utm_medium=email&utm_campaign=NASAJPL&utm_content=grail20131106

Offline Star One

  • Senior Member
  • *****
  • Posts: 13250
  • UK
  • Liked: 3623
  • Likes Given: 220
Re: LIVE: NASA - GRAIL Updates
« Reply #121 on: 06/11/2019 10:00 am »
Used data from the GRAIL mission.

Mass anomaly detected under the moon's largest crater

Quote
A mysterious large mass of material has been discovered beneath the largest crater in our solar system—the Moon's South Pole-Aitken basin—and may contain metal from the asteroid that crashed into the Moon and formed the crater, according to a Baylor University study.

"Imagine taking a pile of metal five times larger than the Big Island of Hawaii and burying it underground. That's roughly how much unexpected mass we detected," said lead author Peter B. James,

Tags:
 

Advertisement NovaTech
Advertisement SkyTale Software GmbH
Advertisement Northrop Grumman
Advertisement
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
1