TDRS L in background and TDRS K in foreground of photo.
The next-generation series of Tracking and Data Relay Satellites (TDRS) provides NASA with crucial crosslink communications capability between Earth-orbiting spacecraft and control and data processing facilities on the ground.
NASA has returned to Boeing to build its next-generation series of Tracking and Data Relay Satellites (TDRS). The new Boeing-built TDRS-K series spacecraft will augment the earlier TDRS constellation that serves as NASA's means of continuous, high-data rate communication with the Hubble Space Telescope, the International Space Station and dozens of unmanned scientific satellites in low earth orbit.