Editing GRACE and GRACE-FO (section)

=== Geophysics ===
[[File:15 Years of Freshwater Trends Seen by GRACE.webm|thumb|left|GRACE uses precise measurements of the motions of two spacecraft in Earth's orbit to track the movement of water through the oceans, land, and atmosphere.]]
[[File:Greenland+Antarctica Mass Loss.png|thumb|Change in mass of the Greenland and Antarctic ice sheets as measured by GRACE]]
GRACE also detects changes in the gravity field due to geophysical processes. [[Glacial isostatic adjustment]]—the slow rise of land masses once depressed by the weight of ice sheets from the last ice age—is chief among these signals.  GIA signals appear as secular trends in gravity field measurements and must be removed to accurately estimate changes in water and ice mass in a region.<ref>{{cite journal |last1=Tregoning |last2=Ramillien |last3=McQueen |last4=Zwartz |s2cid=15724840 |title=Glacial isostatic adjustment and nonstationary signals observed by GRACE |journal=J. Geophys. Res. |date=2009 |volume=114 |issue=B6 |pages=B06406 |doi=10.1029/2008JB006161 |bibcode=2009JGRB..114.6406T|doi-access=free }}</ref>  GRACE is also sensitive to permanent changes in the gravity field due to earthquakes.  For instance, GRACE data have been used to analyze the shifts in the Earth's crust caused by the earthquake that created the 2004 Indian Ocean tsunami.<ref>{{cite news |url=https://www.nytimes.com/2006/08/08/science/08find.html |title=Before the '04 Tsunami, an Earthquake So Violent It Even Shook Gravity |work=The New York Times |first=Kenneth |last=Chang |date=8 August 2006 |access-date=4 May 2010}}</ref>

In 2006, a team of researchers led by Ralph von Frese and Laramie Potts used GRACE data to discover the {{convert|480|km|mi|sp=us|adj=mid|-wide}} [[Wilkes Land crater]] in [[Antarctica]], which was probably formed about 250 million years ago.<ref>{{cite web |url=http://researchnews.osu.edu/archive/erthboom.htm |title=Big Bang in Antarctica—Killer Crater Found Under Ice |publisher=Ohio State University |url-status=dead |archive-url=https://web.archive.org/web/20160306140004/http://researchnews.osu.edu/archive/erthboom.htm |archive-date=6 March 2016}}</ref>

{{clear|left}}