SL-4 R/B (12578)

COSPAR: 1981-063B | Alt Name: Soyuz-U 26-663 Blok-I

DECAYED

Image

Additional Sources

Launch Details

Launch Date

July 2, 1981

Launch Site

PLMSC

Launch Pad

LC43/3

Launch Vehicle

Soyuz-U

Orbital Elements

NORAD ID

12578

International Designator

1981-063B

Decay Date

7/8/1981

Basic Satellite Info

Name

SL-4 R/B

Alternative Name

Soyuz-U 26-663 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

Unknown

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

Satellite Articles

View All Posts »

Learn more about satellites and other related topics.

The Dog They Never Planned to Bring Home

On April 14, 1958, Sputnik 2 burned up over the North Atlantic, carrying the remains of a stray dog from Moscow who had been dead for five months. The Soviet Union told the world she survived for days. It took forty-five years for the truth to come out.

Starship V3 Debut Slips as Booster 19 Rolls to Pad 2 | KeepTrack X Report

Starship V3's maiden flight is delayed as SpaceX rolls Booster 19 to Pad 2 for Flight 9, while Falcon 9 completes its 30th mission of 2026.

X Report 3 Mar 2025

SpaceX gears up for Starship Flight 8, with a launch set for Monday as final preparations are underway.

FCC Shuts SpaceX Out of Key D2D Spectrum, X Report 25 Apr 2026

FCC dismisses SpaceX spectrum challenges, blocking key D2D frequencies. A $57M Golden Dome crosslink demo and software group seat soften the blow.

X Report 13 Mar 2025

SpaceX scrubs Crew-10 launch due to hydraulics issue; successful Falcon 9 launch for NASA missions, and Texas supports SpaceX expansion.

STARLINK-4621 Faces Critical Conjunction as Eight Satellites Reenter | KeepTrack X Report

A HIGH-risk conjunction between STARLINK-4621 and the defunct SL-18 rocket body leads the July 11 safety picture, with eight Starlink satellites set to reenter through July 14.

X Report 29 Aug 2025

SpaceX celebrates a record-breaking Falcon 9 launch while Starship demonstrates strong performance in its recent test flight, fueling excitement for upcoming projects.

Space Brief 16 Sep 2024

Highlights of the day include the Polaris Dawn mission's splashdown, advances in space traffic management, and intriguing astronomy insights from the cloud's edge.