Author Topic: LIVE: NASA - GRAIL Updates  (Read 50451 times)

Online 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 »
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Online jacqmans

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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/

Jacques :-)

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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 .

Jacques :-)

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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).

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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
Jacques :-)

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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
Jacques :-)

Offline dsmillman

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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.

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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 .

Jacques :-)

Offline dsmillman

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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

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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-

Jacques :-)

Online 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
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Offline Apollo-phill

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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

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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!!

Online 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!
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Re: NASA - GRAIL Updates
« Reply #15 on: 01/01/2012 11:55 pm »
Awesome news! Congrats!

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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

Online 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/
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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.
-----------------------------

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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 —

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