X Report 28 Aug 2025
SpaceX continues to break records with the Falcon 9's 30th flight while Starship's successful test flight propels the program forward after recent challenges.
TDRS 4 (19883)
COSPAR: 1989-021B | Alt Name: TDRS 4
Image
Additional Sources
Launch Details
Launch Date
March 13, 1989
Launch Site
Launch Pad
LC39B
Launch Vehicle
Space Shuttle
Orbital Elements
NORAD ID
19883
International Designator
1989-021B
Epoch
Sat, 04 Jul 2026 04:26:28 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
12.81°
Right Ascension
354.93°
Eccentricity
Calculating...
Argument of Perigee
317.25°
Period
1462.16 min
Mean Motion
0.98 rev/day
Latitude
Calculating...
Longitude
Calculating...
Altitude
Calculating...
Velocity
Calculating...
Polar Plot
3D Visualization
Basic Satellite Info
Name
TDRS 4
Alternative Name
TDRS 4
Type
Payload
Status
Non-operational
Owner
GSFC
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 19883U 89021B 26185.18505675 -.00000214 00000-0 00000-0 0 9996
2 19883 12.8094 354.9320 0015859 317.2480 209.4505 0.98484590308210
Source: Celestrak
Summary
TDRS 4, also known as TDRS D, is a communication and data relay satellite managed by GSFC (Goddard Space Flight Center) and manufactured by TRW. Launched on March 13, 1989, from Launch Pad LC39B at AFETR using the Space Shuttle launch vehicle, it achieved stable orbit status on March 14, 1989. The satellite has dimensions of 1.3 meters in length, 2.4 meters in diameter, and a span of 17.4 meters. Its dry mass is 1673 kg, with an initial launch mass of 2245 kg. TDRS 4 features deployable solar arrays for power generation and batteries as backup power sources. The satellite's equipment includes various Ku-band and S-band Traveling Wave Tube Amplifiers (TWTAs) and Solid State Power Amplifiers (SSPAs) used for communication in different bands, including intersatellite links. It has a designed lifetime of 10 years and is equipped with an Attitude and Orbit Control System (AOCS). TDRS 4's shape consists of a box structure with dishes and two panels. The satellite operates primarily for providing communication and data relay services.
Physical Characteristics
Length
1.3
Diameter
2.4
Span
17.4
Dry Mass
1673
Launch Mass
2245
Shape
Box + Dish + 2 Pan
Radar Cross Section
20.9264
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
TDRS D
Purpose
Communication, data relay
Mission
Communication, data relay
Manufacturer
TRW
Life Expectancy
10 years (design)
Bus
TDRS
Configuration
Unknown
Motor
AOCS
Equipment
4 (+2) 25W Ku-band TWTAs for LP (linearly polarized) zone coverage 2 (+2) 1.5W Ku-band TWTAs for CP (circularly polarized) spot coverage 2 (+4) 25W Ku-band TWTAs for LP zone coverage 2 (+2) 1.5W Ku-band TWTAs for CP spot coverage 12 5W TWTAs for LP C-Band up/down 2 (+2) 26W S-band SSPAs (used for intersatellite links) 8 (+4) 3.5W S-band SSPAs (used for intersatellite links)
Power System
2 deployable solar arrays, batteries
ADCS
Unknown
Transmitter Frequency
Unknown
Map
Next Pass
Azimuth Elevation Time (Local)
Start Azimuth
Max Elevation
Stop Azimuth
Time Until
Pass Duration
Satellite Articles
View All Posts »Learn more about satellites and other related topics.
Starship Flight 13 Static Fire, Florida Push, X Report 4 Jul 2026
Starship update July 2026: Flight 13 completed a full six-Raptor static fire as SpaceX targets its first Cape Canaveral Starship launch by year's end.
Starship Flight 13 Set for July 16, Will Deploy Live Starlinks | KeepTrack X Report
SpaceX targets July 16 for Starship Flight 13, testing V3 fixes and deploying functioning Starlink satellites for the first time.
Space Brief 19 Dec 2025
Today's brief highlights significant developments in space defense, innovation fund challenges, and international defense agreements impacting satellite utilities.
Booster 19 Return Imminent as Pad 2 Refinements Continue | KeepTrack X Report
SpaceX is finalizing Pad 2 upgrades at Starbase ahead of Booster 19's return flight, as Starlink's active constellation holds at 10,185 satellites.
Space Brief 4 Apr 2025
Today's highlights include the release of a mystery object by Russian military satellites, SpaceX Fram2 mission insights, Amazon's upcoming satellite launch, and more.
The Day We First Landed on Venus
On December 15, 1970, a battered Soviet probe accomplished something no spacecraft had done before - it survived landing on another world and lived to tell about it.
X Report 15 Dec 2025
SpaceX made significant strides in satellite deployment with successful launches of 27 and 29 Starlink satellites, marking both a milestone in landings and ongoing expansion of the Starlink constellation.