SL-12 R/B(2) (21129)

COSPAR: 1991-010F | Alt Name: Blok DM-2 No. 38L

Image
SL-12 R/B(2) Satellite Image
Additional Sources
Launch Details

Launch Date

February 14, 1991

Launch Pad

LC200/39

Launch Vehicle

Proton-K/DM-2

Orbital Elements

NORAD ID

21129

International Designator

1991-010F

Epoch

Sat, 04 Jul 2026 04:23:21 GMT

Apogee

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Perigee

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Inclination

13.14°

Right Ascension

342.25°

Eccentricity

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Argument of Perigee

232.59°

Period

1437.81 min

Mean Motion

1.00 rev/day

Latitude

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Longitude

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Altitude

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Velocity

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Polar Plot
3D Visualization
Basic Satellite Info

Name

SL-12 R/B(2)

Alternative Name

Blok DM-2 No. 38L

Type

Rocket Body

Status

Space Junk

Owner

RVSN

Country

USSR

Constellation

N/A

Related Satellites

Major Events

N/A

Latest TLEs
1 21129U 91010F   26185.18289007 -.00000136  00000-0  00000-0 0  9994
2 21129  13.1412 342.2484 0017237 232.5902 294.5644  1.00152557129843

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

6.3

Diameter

3.7

Span

6.3

Dry Mass

2440

Launch Mass

17490

Shape

Cyl

Radar Cross Section

3.124

Visual Magnitude

Unknown

Color

Unknown

Material Composition

Unknown

Technical Details

Payload

11S861 No. 38L

Purpose

Unknown

Mission

Unknown

Manufacturer

NPOE

Life Expectancy

Unknown

Bus

Blok DM

Configuration

Unknown

Motor

Unknown

Equipment

Unknown

Power System

Unknown

ADCS

Unknown

Transmitter Frequency

Unknown

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