Space Force Orders 14 GPS 3F Satellites for $514M | KeepTrack Space Brief
Space Force awards Lockheed Martin $514M for two additional GPS 3F satellites, bringing total orders to 14. New satellites add anti-jam features and upgraded civilian signals.
SL-6 R/B(2) (21121)
COSPAR: 1991-012D | Alt Name: Blok-ML No. 185
Image
Additional Sources
Launch Details
Launch Date
February 15, 1991
Launch Site
PLMSC
Launch Pad
LC43/3
Launch Vehicle
Molniya 8K78M
Orbital Elements
NORAD ID
21121
International Designator
1991-012D
Epoch
Sat, 04 Jul 2026 22:26:01 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
64.65°
Right Ascension
164.11°
Eccentricity
Calculating...
Argument of Perigee
253.26°
Period
699.69 min
Mean Motion
2.06 rev/day
Latitude
Calculating...
Longitude
Calculating...
Altitude
Calculating...
Velocity
Calculating...
Polar Plot
3D Visualization
Basic Satellite Info
Name
SL-6 R/B(2)
Alternative Name
Blok-ML No. 185
Type
Rocket Body
Status
Space Junk
Owner
RVSN
Country
USSR
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 21121U 91012D 26185.93473606 -.00000515 00000+0 00000+0 0 9990
2 21121 64.6491 164.1142 6467505 253.2631 30.6333 02.05805920 97491
Source: Celestrak
Summary
A rocket body, also commonly referred to as an upper stage or spent rocket stage, is the structural shell left behind after a rocket has delivered its payload to orbit. These large and often heavy pieces of space hardware can remain in orbit for years, posing significant collision hazards as part of the growing space debris problem. If left uncontrolled, rocket bodies have the potential to reenter Earth's atmosphere unpredictably, which can lead to falling debris in populated areas. Additionally, they risk colliding with operational satellites or the International Space Station, creating more debris and putting human life at risk.
Physical Characteristics
Length
3.3
Diameter
2.3
Span
3.3
Dry Mass
900
Launch Mass
4500
Shape
Cyl
Radar Cross Section
7.5708
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Blok-ML No. 185
Purpose
Unknown
Mission
Unknown
Manufacturer
NPOE
Life Expectancy
Unknown
Bus
Blok-L
Configuration
Unknown
Motor
Unknown
Equipment
Unknown
Power System
Unknown
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.
X Report 10 Feb 2025
SpaceX prepares for Starship Flight 8 with successful booster static fire; Starlink continues its expansion.
Vulcan Booster Anomaly Under Scrutiny After USSF-87 Launch | KeepTrack Space Brief
ULA Vulcan faces scrutiny after solid booster anomaly on USSF-87 mission. ThinKom wins portable satellite ground station contract. Space Force starts Project Hecate for GPS past 2040.
Space Brief 13 Dec 2025
Today's briefing covers a new naming system by Space Force, China's space advances, drone defense at Cape Canaveral, and more military updates impacting space operations.
STS-30 | When Atlantis Sent a Radar to Venus
On May 4, 1989, Space Shuttle Atlantis lifted off from LC-39B carrying Magellan, NASA's first interplanetary mission since 1978. The eleven-year drought ended in a payload bay, and the radar that emerged would map ninety-eight percent of Venus through clouds that no camera could ever see through.
SpaceX Hits 10,000 Starlink Satellites in Orbit | KeepTrack Space Brief
SpaceX surpassed 10,000 simultaneous Starlink satellites in orbit after Starlink 17-24 deployed 25 satellites from California. Milestone reached in under 7 years.
Space Brief 3 Jan 2025
Today's brief covers the recent surge in SpaceX launches, Eutelsat's resolution of a OneWeb software issue, and various strategic previews for U.S. military branches in 2025.
Space Brief 24 Nov 2025
Today's highlights include a record number of launches from Florida's Space Coast, Germany's new military space strategy, SpaceX's Starlink deployment, and more.