Falcon Heavy Returns After 18-Month Hiatus for ViaSat-3 | KeepTrack X Report
SpaceX's Falcon Heavy lifts off for the 12th time after 18 months grounded, delivering the final ViaSat-3 satellite from LC-39A at 10:21 a.m. EDT.
SL-6 R/B(2) (21429)
COSPAR: 1991-043D | Alt Name: Blok-ML No. 186
Image
Additional Sources
Launch Details
Launch Date
June 18, 1991
Launch Site
PLMSC
Launch Pad
LC43/4
Launch Vehicle
Molniya 8K78M
Orbital Elements
NORAD ID
21429
International Designator
1991-043D
Epoch
Mon, 22 Jun 2026 05:28:23 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
63.64°
Right Ascension
247.68°
Eccentricity
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Argument of Perigee
262.15°
Period
732.21 min
Mean Motion
1.97 rev/day
Latitude
Calculating...
Longitude
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Altitude
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Velocity
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Polar Plot
3D Visualization
Basic Satellite Info
Name
SL-6 R/B(2)
Alternative Name
Blok-ML No. 186
Type
Rocket Body
Status
Space Junk
Owner
RVSN
Country
USSR
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 21429U 91043D 26173.22804958 .00000620 00000-0 00000-0 0 9990
2 21429 63.6441 247.6774 6840356 262.1475 21.7116 1.96663885251468
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
7.1655
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Blok-ML No. 186
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
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