The new GRACE-FO satellites are replacing a previous pair of satellites that dutifully monitored global changes for over 15 years.
NASA's twin GRACE Follow-On spacecraft (top) and five Iridium Next communications satellites are stacked like a cake before being loaded onto a SpaceX Falcon 9 rocket for a May 22, 2018, launch into orbit from California's Vandenberg Air Force Base.
Live coverage of the countdown and launch of a SpaceX Falcon 9 rocket from Vandenberg Air Force Base in California with five next-generation Iridium communications satellites and two U.S. It will also mark the eleventh time the company has re-used its first stage rocket boosters, including the two that were part of the Falcon Heavy.
Sadly for fans of the Falcon 9 party trick of landing fiery-end down, SpaceX does not intend to attempt to recover the rocket for a second time. The result is a monthly map of the Earth's gravity field and gives clues as to how mass (normally water) is moving around the planet.More news: Gas prices continue to climb at unofficial start of summer
SpaceX also plans to use the Block 5 to ferry astronauts to the International Space Station, a plan that awaits certification and approval by NASA.
He said SpaceX had tried but failed to catch the payload fairing, a nose cone used to protect the rocket, as it plunged into the ocean. The work has been ongoing for over a decade now, and these two new satellites are replacements for older ones that served a similar objective. After a rest, the rocket's upper stage reignited its engines and adjusted its orbit for the release of five Iridium Next communications satellites. Second burn and Iridium orbit good.... GRACE-FO, a collaborative mission of NASA and the German Research Centre for Geosciences (GFZ), continues the work of the original GRACE mission in observing the movement of water and other mass around our planet by tracking the changing pull of gravity very precisely.
The Iridium Next satellites are less interesting: They will join the 50 Iridium Next satellites already floating in space that, according to Space.com, will eventually make up part of the 75-satellite communications constellation. If needed, an additional launch opportunity is available on Wednesday, May 23.
Once the Earth-facing satellite has put a safe distance between itself and its sibling, it will thrust back up into a higher orbit, so that one follows the other on the same trajectory. GRACE-Fo is a joint project between NASA and Germany's GFZ German Research Center for Geosciences. "You can't manage it well until you can measure it. GRACE-FO provides a unique way to measure water in many of its phases, allowing us to manage water resources more effectively".