The joint Gravity Recovery and Climate Experiment (GRACE) mission between Nasa and German Aerospace Centre (DLR) has come to an end after 15 years of operation.

Launched on 17 March 2002 aboard a Rockot launcher from the Russian cosmodrome in Plesetsk, the mission includes a pair of satellites, namely GRACE-1 and GRACE-2.

During their operation, both satellites orbited the Earth in close formation to precisely record the changes occurring in the planet’s gravity field.

The mission also provided data on the effects of climate change.

“The two GRACE satellites have delivered scientific data that has reshaped our understanding of Earth’s geophysical processes.”

DLR executive board chair Pascale Ehrenfreud said: “The GRACE mission was planned to last five years but has been working very successfully for more than 15 years, three times longer than originally planned.

“The two GRACE satellites have delivered scientific data that has reshaped our understanding of Earth’s geophysical processes.

“The mission has demonstrated what satellite-supported Earth observation can do for climate research and the observation of climate change.”

Using its two ground stations in Germany, DLR’s German Space Operations Centre has been operating the two GRACE satellites.

According to DLR, failure of eight of the 20 battery cells onboard GRACE-2 has reduced the capacity of the probe’s ageing battery to an extent to which the satellite will no longer able to support its scientific mission.

In 2013, GRACE-2’s battery cells began showing the first signs of ageing.

With no fuel, the satellite is expected to quickly lose altitude due to the resistance of the residual atmosphere, but will not pose any risk of a collision with GRACE-1, which is set to go through some final tests before being put out of operation over the coming weeks.

Both Nasa and DLR will jointly monitor GRACE-2’s re-entry and burning up in the atmosphere.

A successor mission GRACE Follow-On is expected to be launched from Vandenberg in California, US, on a SpaceX Falcon 9 rocket next year.