OKEAN-3 (21397)

COSPAR: 1991-039A | Alt Name: Okean

Image

Additional Sources

Launch Details

Launch Date

June 4, 1991

Launch Site

PLMSC

Launch Pad

LC32/2

Launch Vehicle

Tsiklon-3

Orbital Elements

NORAD ID

21397

International Designator

1991-039A

Epoch

Sat, 04 Jul 2026 02:07:45 GMT

Apogee

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Perigee

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Inclination

82.51°

Right Ascension

223.99°

Eccentricity

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Argument of Perigee

295.69°

Period

95.66 min

Mean Motion

15.05 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

OKEAN-3

Alternative Name

Okean

Type

Payload

Status

Unknown

Owner

RGMS/YUZH

Country

USSR

Constellation

N/A

Related Satellites

Major Events

N/A

Latest TLEs

1 21397U 91039A   26185.08871712  .00002434  00000-0  16762-3 0  9998

2 21397  82.5143 223.9915 0012142 295.6867  64.3106 15.05398118882549

Source: Celestrak

Summary

OKEAN-3, also known as Okean, is an ocean observation satellite with the NORAD catalog ID 21397 and object identifier 1991-039A. Launched on June 4, 1991, from the Plesetsk Missile and Space Complex (PLMSC) using a Tsiklon-3 launch vehicle, OKEAN-3 was manufactured by YUZH for RGMS/YUZH. The satellite is part of the Okean series and carries an ocean observation payload called Okean-O1 No. 6L. It has dimensions of approximately 5 meters in length, 2.4 meters in diameter, and a span of 21.5 meters when its solar arrays are deployed. Its dry mass is 1907 kg, which matches the launch mass as well. The satellite's mission was to observe ocean conditions, utilizing equipment such as RLSBO (3.2 cm), RM-0.8, MWP (3.2 cm), RTVK, MSU-SK, and Kondor. It featured two deployable solar arrays for power generation along with batteries. Its shape is described as cylindrical with two panels and antennas, and it had an operational lifetime of approximately 2 years.

Physical Characteristics

Length

Diameter

2.4

Span

21.5

Dry Mass

1907

Launch Mass

1907

Shape

Cyl + 2 Pan + Ant

Radar Cross Section

8.213

Visual Magnitude

Unknown

Color

Unknown

Material Composition

Unknown

Technical Details

Payload

Okean-O1 No. 6L

Purpose

Ocean Observation

Mission

Ocean Observation

Manufacturer

YUZH

Life Expectancy

2 years

Bus

Okean

Configuration

Unknown

Motor

Unknown

Equipment

RLSBO (3.2 cm), RM-0.8, MWP (3.2 cm), RTVK, MSU-SK, Kondor

Power System

2 deployable solar arrays, batteries

ADCS

Unknown

Transmitter Frequency

Unknown

Map

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