Tracking and Data Relay Satellites (TDRS)

NASA’s Tracking and Data Relay Satellites (TDRS) provide communications services to NASA’s most storied missions. Since 1983, NASA has launched a constellation of TDRS that reside in geosynchronous orbit, which is a high-altitude orbit of about 22,000 miles. With this orbit, TDRS remains above the same relative point on the ground as the planet rotates. This means TDRS have a wider view of Earth and near-Earth space where most spacecraft operate than the lower-orbit-user spacecraft do.  

TDRS serves as a bent-pipe relay system transmitting user data between spacecraft and the ground. As spacecraft orbit Earth, TDRS collects their data and sends it back down to NASA ground stations. It also completes this process in reverse, allowing users on the ground to command their spacecraft.

TDRS is crucial to provide two-way communications 24/7 from Earth to space and back. Increased connectivity ensures the health and safety of humans and spacecraft in space! And with NASA’s upcoming Artemis missions, sending the first woman and first person of color to the Moon, connecting our astronauts to Earth is more important than ever. TDRS will be a critical component during Artemis mission launches. Here, you can learn more about TDRS with these fun activities.