Just a few weeks after kicking off a historic journey to Mars, NASA is set to jump-start another mission from Vandenberg Air Force Base — this time with an interest in monitoring the movement of water here on Earth.
The Gravity Recovery and Climate Experiment Follow-On, or GRACE-FO, mission is slated to begin with the launch of a pair of satellites aboard a SpaceX Falcon 9 rocket at 12:47 p.m. May 22 from VAFB’s Space Launch Complex-4E. The rocket had been slated for blast-off at 4:04 p.m. Saturday, but a spokesman for NASA's Jet Propulsion Laboratory confirmed late Tuesday night that the launch had been pushed back to no sooner than May 22.
The rocket, when it does launch, is also slated to carry the latest set of five Iridium NEXT satellites as the communications company continues to fill out its next-generation constellation.
The GRACE-FO mission is a joint effort between NASA and the German Research Centre for Geosciences. GRACE-FO, according to NASA, is expected to provide critical measurements that will be used together with other data to monitor the movement of water masses across Earth and mass changes within Earth itself.
“Monitoring changes in ice sheets and glaciers, underground water storage, and sea level provides a unique view of Earth’s climate and has far-reaching benefits,” read a portion of a statement put out by NASA about the mission.
The mission is scheduled to fly at least five years.
The separate Iridium portion of the launch will mark that company’s sixth in its Iridium NEXT launch series, and the second of this year. The most recent Iridium NEXT launch occurred March 30, while the previous four were all in 2017. All of the launches have been from VAFB.
Iridium has put 50 satellites into orbit through the series of NEXT launches, with another 25 still planned for deployment. The company has said that it intends to complete the constellation this year, likely with just two more launches following the one planned for Saturday.
Iridium NEXT is the company's $3 billion next-generation mobile, global satellite network.
The upcoming launch, if it goes off as planned, would be the first from VAFB since the May 5 InSight Mission to Mars, which was the first ever interplanetary mission to launch from the West Coast. The InSight lander is expected to arrive on Mars in November.
NASA will provide coverage of the launch on NASA Television and on the agency’s website.