In just over 15 minutes from Space Launch Complex-3 at Vandenberg Space Force Base in California, the United Launch Alliance Atlas V 401 rocket carrying Landsat 9 will rumble to life, sending the NASA-U.S. Geological Survey (USGS) Earth-monitoring satellite on its mission. The fuel fill sequence has been initiated, and the rocket is being fueled with liquid oxygen (LO2) and rocket-grade kerosene (RP-1).
Prior to launch, targeted for 11:12 a.m. PDT (2:12 p.m. EDT), several sequences will be performed to ensure launch success. The fuel fill sequence will be completed, water deluge system actuation pressure adjustment will be performed, the LO2 in the Atlas booster and Centaur second stage will reach flight levels, as well as the liquid hydrogen fuel levels in the Centaur. Final launch polls are conducted and before a go to continue countdown, at which time the spacecraft transfers to internal power and an automatic computer sequencer takes control for all critical events through liftoff. Fuel tanks reach flight pressure, and the Atlas first stage and Centaur second stage switch to internal power. The launch control system is enabled, and ‘go’ for launch is verified before entering terminal countdown.
Landsat 9 will join its sister satellite, Landsat 8, in orbit, collecting images from across the planet every eight days. This calibrated data will continue the Landsat program’s critical role in monitoring the health of Earth and helping people manage essential resources, including crops, irrigation water, and forests. To learn more about how NASA’s Earth science work makes a difference in people’s lives around the world every day, follow @NASAEarth on Twitter, NASA Earth on Facebook, and NASAEarth on Instagram.