SL-4 R/B (12617)

COSPAR: 1981-068B | Alt Name: Soyuz-U 39-421 Blok-I

DECAYED

Image

Additional Sources

Launch Details

Launch Date

July 29, 1981

Launch Site

PLMSC

Launch Pad

LC41/1

Launch Vehicle

Soyuz-U

Orbital Elements

NORAD ID

12617

International Designator

1981-068B

Decay Date

7/31/1981

Basic Satellite Info

Name

SL-4 R/B

Alternative Name

Soyuz-U 39-421 Blok-I

Type

Rocket Body

Status

Space Junk

Owner

RVSN

Country

USSR

Constellation

N/A

Related Satellites

Major Events

N/A

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

6.7

Diameter

2.7

Span

6.7

Dry Mass

2350

Launch Mass

2350

Shape

Cyl

Radar Cross Section

22.3211

Visual Magnitude

Unknown

Color

Unknown

Material Composition

Unknown

Technical Details

Payload

11S510

Purpose

Unknown

Mission

Unknown

Manufacturer

PROG

Life Expectancy

Unknown

Bus

Blok-I

Configuration

Unknown

Motor

Unknown

Equipment

Unknown

Power System

Unknown

ADCS

Unknown

Transmitter Frequency

Unknown

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