HOUSTON, May 21 (UPI) -- The crew of space shuttle Atlantis spent Thursday preparing for the journey back to Earth and the Kennedy Space Center in Florida.
The crew completed a test of the reaction control system steering thrusters that will help control the space shuttle's attitude and speed after Friday's de-orbit burn. They also tested the shuttle aerosurfaces and flight control systems that will be used once the shuttle enters the Earth's atmosphere.
The STS-125 crew performed five spacewalks during their mission to repair and upgrade the Hubble Space Telescope.
The space center landing is scheduled to occur at 10:00 a.m. EDT, weather permitting, with a second landing opportunity available at 11:39 a.m.