. 24/7 Space News .
PHYSICS NEWS
GRACE Mission Making Plans for Final Science Data Collection
by Staff Writers
Washington DC (SPX) Sep 19, 2017


Illustration of the Gravity Recovery and Climate Experiment (GRACE) twin satellites in orbit.

With one of its twin satellites almost out of fuel after more than 15 years of chasing each other around our planet to measure Earth's ever-changing gravity field, the operations team for the U.S./German Gravity Recovery and Climate Experiment (GRACE) mission is making plans for an anticipated final science collection.

On Sept. 3, one of 20 battery cells aboard the GRACE-2 satellite stopped operating due to an age-related issue. It was the eighth battery cell loss on GRACE-2 since the twin satellites that compose the GRACE mission launched in March 2002 on a mission designed to last five years. The following day, contact was lost with GRACE-2.

On Sept. 8, following numerous attempts, the GRACE mission operations team at NASA's Jet Propulsion Laboratory in Pasadena, California; Deutsches Zentrum fur Luft- und Raumfahrt (DLR, the German Aerospace Center) in Oberpfaffenhofen, Germany; and the Helmholtz Centre Potsdam German Research Centre for Geosciences (GFZ) in Potsdam, Germany, uplinked commands to GRACE-2 to bypass the satellite's flight software system.

The procedure restored communications with the spacecraft, allowing the team to regain control. Subsequent analyses revealed that the battery cell lost on Sept. 3 had recovered its full voltage, and that GRACE-2 had essentially hibernated during the period of lost contact, consuming no fuel. Following an assessment of the satellite's overall health, the team has determined that GRACE's dual satellite science mission can continue.

The team has uplinked commands to GRACE-2 to place it in a passive state that will allow it to maintain its current level of fuel. Operational procedures have begun that will extend the GRACE mission to its next science operations phase, which runs from mid-October to early November. During that time, GRACE-2 will be in full Sun, so it will not need to use its batteries.

The team expects the October/November science data collection to be the mission's last before GRACE-2 runs out of fuel. The additional monthly gravity map produced will help further extend GRACE's data record closer to the launch of GRACE's successor mission, GRACE-Follow-On, scheduled for early 2018.

As directed by the mission's Joint Steering Group, final decommissioning for both GRACE-1 and GRACE-2 will begin once the dual satellite science phase concludes.

GRACE tracks the movement of water around our planet caused by Earth's changing seasons, weather and climate processes, and human activities. The mission has mapped Earth's ever-changing gravity field in unprecedented detail, showing how water, ice and solid Earth material move on or near Earth's surface. GRACE operates by sensing minute changes in gravitational pull caused by local changes in Earth's mass.

To observe these changes, GRACE uses a microwave ranging system that measures micron-scale variations in the 137-mile (220-kilometer) distance between the spacecraft, along with GPS tracking, star trackers for attitude information and an accelerometer to account for non-gravitational effects such as atmospheric drag. From these data collected over Earth's surface, scientists can infer Earth's gravity field.

GRACE's monthly maps of regional variations in gravity have given scientists new insights into Earth system processes. Among its many innovations, GRACE has been used to monitor the loss of ice from Earth's ice sheets, improve understanding of the processes responsible for sea level rise and ocean circulation, provide insights into where aquifers may be shrinking or where dry soils are contributing to drought, and monitor changes in the solid Earth.

PHYSICS NEWS
Granting weightless wishes
Paris (ESA) Aug 28, 2017
ESA this week helped to provide children with disabilities the opportunity to experience weightlessness and lunar gravity on aircraft flights. Eight children from five ESA member states - UK, France, Germany, Belgium, and Italy -boarded the converted Airbus A310 in Bordeaux, France on 24 August as part of the Kid's Weightless Dreams campaign organised by Novespace and Reves de Gosse. ... read more

Related Links
GRACE at NASA
The Physics of Time and Space


Thanks for being there;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Monthly Supporter
$5+ Billed Monthly


paypal only
SpaceDaily Contributor
$5 Billed Once


credit card or paypal


Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

PHYSICS NEWS
Diet tracker in space

Three astronauts blast off for five-month ISS mission

Crewed Missions Beyond LEO

Voyager Spacecraft: 40 Years of Solar System Discoveries

PHYSICS NEWS
Arianespace announces a new contract, bringing its order book to 53 launches across three rockets

EUMETSAT signs with Arianespace for first Metop-SG satellite launch

MHI to launch first Inmarsat-6 satellite

Proton-M Rocket Launches Spanish Satellite Amazonas-5 Into Orbit

PHYSICS NEWS
45 Kilometers on the Odometry for Opportunity

New tools for exploring the surface of Mars

NASA's Curiosity Mars Rover Climbing Toward Ridge Top

New Gravity Map Suggests Mars Has a Porous Crust

PHYSICS NEWS
Spacecraft passes docking test

China, Russia to Have Smooth Space Cooperation, Says Expert

Kuaizhou-11 to send six satellites into space

Russia, China May Sign 5-Year Agreement on Joint Space Exploration

PHYSICS NEWS
India, Japan Set to Boost Space Cooperation

Bids for government funding prove strong interest in LaunchUK

Blue Sky Network Reaffirms Commitment to Brazilian Market

India to Launch Exclusive Satellite for Afghanistan

PHYSICS NEWS
Dormant, Yet Always-Alert Sensor Awakes Only in the Presence of a Signal of Interest

Air Force activates new satellites for tracking space objects

'Peel-and-go' printable structures fold themselves

Ultrathin spacecraft will collect, deposit orbital debris

PHYSICS NEWS
Hubble observes pitch black planet

The return of the comet-like exoplanet

Does the Organic Material of Comets Predate our Solar System?

X-rays Reveal Temperament of Possible Planet-hosting Stars

PHYSICS NEWS
Hibernation Over, New Horizons Continues Kuiper Belt Cruise

Pluto features given first official names

Jupiter's Auroras Present a Powerful Mystery

New Horizons Files Flight Plan for 2019 Flyby









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.