ESA's Proba-3 Formation-Flyer Goes Silent | KeepTrack Space Brief
ESA's Proba-3 spacecraft lost contact last month, grounding the dual-satellite solar eclipse mission. Formation flying between both craft is critical for coronagraph science.
SL-8 R/B (04255)
COSPAR: 1969-103B | Alt Name: Kosmos-3M No. 41LM Stage 2
Image
Additional Sources
Launch Details
Launch Date
November 24, 1969
Launch Site
PLMSC
Launch Pad
LC132/1
Launch Vehicle
Kosmos 11K65M
Orbital Elements
NORAD ID
04255
International Designator
1969-103B
Epoch
Fri, 03 Jul 2026 17:04:10 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
74.02°
Right Ascension
275.40°
Eccentricity
Calculating...
Argument of Perigee
175.73°
Period
108.30 min
Mean Motion
13.30 rev/day
Latitude
Calculating...
Longitude
Calculating...
Altitude
Calculating...
Velocity
Calculating...
Polar Plot
3D Visualization
Basic Satellite Info
Name
SL-8 R/B
Alternative Name
Kosmos-3M No. 41LM Stage 2
Type
Rocket Body
Status
Space Junk
Owner
RVSN
Country
USSR
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 04255U 69103B 26184.71123537 .00000036 00000-0 11977-3 0 9992
2 04255 74.0156 275.3986 0010971 175.7286 337.5173 13.29654431746537
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
4.2
Diameter
2.4
Span
4.2
Dry Mass
1434
Launch Mass
1434
Shape
Cyl
Radar Cross Section
4.2506
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
S3M
Purpose
Unknown
Mission
Unknown
Manufacturer
YUZH
Life Expectancy
Unknown
Bus
S3
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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