TDRS
Operated by NASA
Data current as of 2026-07-20.
The Tracking and Data Relay Satellite System is NASA's network of geostationary relay spacecraft. It carries communications between low-orbiting missions, including the International Space Station, and the ground.
TDRS accounts for 12 cataloged objects, of which 12 are in orbit and 8 are active. The first launched in 1983, the most recent in 2017. The busiest year was 2002, with 2 added. Most fly near a 13-degree inclination with an orbital period around 1436 minutes.
TDRS launched per year
Typical specifications
Most common values across cataloged TDRS satellites.
| Manufacturer | TRW |
|---|---|
| Purpose | Communication, data relay |
| Launch mass | 3454 kg |
| Dry mass | 1673 kg |
| Length | 1.3 m |
| Diameter | 2.4 m |
| Span | 17.4 m |
| Shape | Box + Dish + 2 Pan |
| Power | 2 deployable solar arrays, batteries |
| Propulsion | R-4D-11-300 |
| Design life | 10 years (design) |
| Equipment | ? |
| Typical orbit | 1436 min period, 13° inclination |
Spacecraft buses
The platforms TDRS satellites are built on.
Launched on
TDRS satellites
Track any of them live in KeepTrack.
| Name | NORAD | COSPAR | Bus | Launched | Orbit | Status | Track |
|---|---|---|---|---|---|---|---|
| TDRS 13 TDRS 13 | 42915 | 2017-047A | BSS-601HP | Aug 18, 2017 | 1436 min, 3.5° | Active | ◉ |
| TDRS 12 TDRS 12 | 39504 | 2014-004A | BSS-601HP | Jan 24, 2014 | 1436 min, 4.0° | Active | ◉ |
| TDRS 11 TDRS 11 | 39070 | 2013-004A | BSS-601HP | Jan 31, 2013 | 1436 min, 3.6° | Active | ◉ |
| TDRS 10 TDRS 10 | 27566 | 2002-055A | HS-601 | Dec 5, 2002 | 1457 min, 10.2° | Inactive | ◉ |
| TDRS 9 TDRS 9 | 27389 | 2002-011A | HS-601 | Mar 8, 2002 | 1455 min, 12.2° | Inactive | ◉ |
| TDRS 8 TDRS 8 | 26388 | 2000-034A | HS-601 | Jun 30, 2000 | 1436 min, 12.7° | Active | ◉ |
| TDRS 7 TDRS 7 | 23613 | 1995-035B | TDRS | Jul 13, 1995 | 1436 min, 13.4° | Active | ◉ |
| TDRS 6 TDRS-6 | 22314 | 1993-003B | TDRS | Jan 13, 1993 | 1436 min, 14.2° | Active | ◉ |
| TDRS 5 TDRS 5 | 21639 | 1991-054B | TDRS | Aug 2, 1991 | 1436 min, 14.1° | Active | ◉ |
| TDRS 4 TDRS 4 | 19883 | 1989-021B | TDRS | Mar 13, 1989 | 1462 min, 12.8° | Inactive | ◉ |
| TDRS 3 TDRS 3 | 19548 | 1988-091B | TDRS | Sep 29, 1988 | 1436 min, 12.6° | Active | ◉ |
| TDRS 1 TDRS 1 | 13969 | 1983-026B | TDRS | Apr 4, 1983 | 1458 min, 8.6° | Inactive | ◉ |
Frequently asked questions
How many TDRS satellites are in orbit?
12 TDRS objects are currently in orbit, out of 12 ever cataloged. 0 have reentered.
How many TDRS satellites are active?
8 TDRS satellites carry an active status in the catalog.
When did the first TDRS satellite launch?
The first cataloged TDRS object launched in 1983, and the most recent in 2017.
Who operates TDRS?
TDRS is operated by NASA.
How can I track TDRS satellites?
You can track the TDRS fleet live in the KeepTrack 3D tracker, or open any individual satellite from the list on this page.