SKYNET 4D (25134)

COSPAR: 1998-002A | Alt Name: Skynet 4D

Image

Additional Sources

Launch Details

Launch Date

January 10, 1998

Launch Site

Cape Canaveral Space Force Station

Launch Pad

LC17B

Launch Vehicle

Delta 7925-9.5

Orbital Elements

NORAD ID

25134

International Designator

1998-002A

Epoch

Sat, 04 Jul 2026 04:32:50 GMT

Apogee

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Perigee

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Inclination

12.82°

Right Ascension

10.66°

Eccentricity

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Argument of Perigee

162.82°

Period

1452.27 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 4D

Alternative Name

Skynet 4D

Type

Payload

Status

Non-operational

Owner

MOD

Country

United Kingdom

Constellation

N/A

Related Satellites

Major Events

N/A

Latest TLEs

1 25134U 98002A   26185.18947676 -.00000063  00000-0  00000-0 0  9994

2 25134  12.8239  10.6615 0004637 162.8178  11.6193  0.99155355103540

Source: Celestrak

Summary

SKYNET 4D, also known as Skynet 4D, is a military communication satellite operated by the UK Ministry of Defence (MOD). Launched on January 10, 1998, from Cape Canaveral Air Force Station using a Delta 7925-9.5 launch vehicle, it was manufactured by Matra Marconi Space Systems (MMSS) and is based on the ECS-Bus configuration. The satellite measures approximately 2.1 meters in length with a diameter of 1.9 meters and spans up to 16 meters when its solar arrays are deployed. Its dry mass is 720 kg, while it had a launch mass of 823 kg. SKYNET 4D is equipped with four SHF transponders, two UHF transponders, and two C-band transponders for various communication purposes. It uses solar arrays and batteries for power supply and has a reflective surface area (RCS) of about 15.9489 square meters. The satellite was intended to operate for approximately six years as part of the UK's military communication capabilities.

Physical Characteristics

Length

2.1

Diameter

1.9

Span

Dry Mass

720

Launch Mass

823

Shape

Box + 2 Pan

Radar Cross Section

15.9489

Visual Magnitude

Unknown

Color

Unknown

Material Composition

Unknown

Technical Details

Payload

Skynet 4D

Purpose

Military communication

Mission

Military communication

Manufacturer

MMSS

Life Expectancy

6 years

Bus

ECS

Configuration

ECS-Bus

Motor

Star 30E

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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