SKYNET 4C (20776)

COSPAR: 1990-079A | Alt Name: Skynet 4C

Image

Additional Sources

Launch Details

Launch Date

August 30, 1990

Launch Site

FRGUI

Launch Pad

ELA2

Launch Vehicle

Ariane 44LP

Orbital Elements

NORAD ID

20776

International Designator

1990-079A

Epoch

Fri, 03 Jul 2026 23:43:20 GMT

Apogee

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Perigee

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Inclination

13.33°

Right Ascension

349.70°

Eccentricity

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Argument of Perigee

129.80°

Period

1460.79 min

Mean Motion

0.99 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

SKYNET 4C

Alternative Name

Skynet 4C

Type

Payload

Status

Operational

Owner

MOD

Country

United Kingdom

Constellation

N/A

Related Satellites

Major Events

N/A

Latest TLEs

1 20776U 90079A   26184.98842789  .00000000  00000-0  00000-0 0  9993

2 20776  13.3328 349.7038 0003350 129.7984  57.7942  0.98576530   208

Source: Celestrak

Summary

SKYNET 4C, also known as Skynet 4C, is a military communication satellite launched by the UK's Ministry of Defence on August 30, 1990. It was manufactured by BAES and uses an ECS-Bus configuration with a total launch mass of 1430 kg and a dry mass of 655 kg. The satellite measures 2.1 meters in length, has a diameter of 1.9 meters, and spans up to 16 meters when its solar arrays are deployed. Its equipment includes 4 SHF transponders, 2 UHF transponders, and 2 C-band transponders. SKYNET 4C was launched from ELA-2 at the Guiana Space Centre using an Ariane 44LP launch vehicle with a TE-M-700-19 motor and is designed for a six-year lifetime. It uses two deployable solar arrays and batteries for power, and its shape consists of a box with two panels. The satellite's purpose is to support military communication needs.

Physical Characteristics

Length

2.1

Diameter

1.9

Span

Dry Mass

655

Launch Mass

1430

Shape

Box + 2 Pan

Radar Cross Section

11.1055

Visual Magnitude

Unknown

Color

Unknown

Material Composition

Unknown

Technical Details

Payload

Skynet 4C

Purpose

Military communication

Mission

Military communication

Manufacturer

BAES

Life Expectancy

6 years

Bus

ECS

Configuration

ECS-Bus

Motor

TE-M-700-19

Equipment

4 SHF transponders (all), 2 UHF transponders (all), 2 C-band transponders (#D-F)

Power System

2 deployable solar arrays, batteries

ADCS

Unknown

Transmitter Frequency

Unknown

Map

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Latitude

Longitude

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