CAT 4 (13011)

COSPAR: 1981-122B | Alt Name: CAT 04/Thesee

Image
CAT 4 Satellite Image
Additional Sources
Launch Details

Launch Date

December 20, 1981

Launch Site

FRGUI

Launch Pad

ELA1

Launch Vehicle

Ariane 1

Orbital Elements

NORAD ID

13011

International Designator

1981-122B

Epoch

Sat, 04 Jul 2026 01:33:50 GMT

Apogee

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Perigee

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Inclination

10.50°

Right Ascension

117.06°

Eccentricity

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Argument of Perigee

356.14°

Period

435.93 min

Mean Motion

3.30 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

CAT 4

Alternative Name

CAT 04/Thesee

Type

Payload

Status

Non-operational

Owner

ESA

Country

European Space Agency

Constellation

N/A

Related Satellites

Major Events

N/A

Latest TLEs
1 13011U 81122B   26185.06516928  .00006854  00000-0  95057-3 0  9991
2 13011  10.5034 117.0610 6522465 356.1427   0.5733  3.30326632361427

Source: Celestrak

Summary
CAT 4, also known as CAT 04/Thesee, is an ESA-owned satellite with the OBJECT_ID 1981-122B and a NORAD_CAT_ID of 13011. Launched on December 20, 1981, from ELA1 at FRGUI using an Ariane 1 launch vehicle, this spacecraft was designed for vehicle evaluation purposes. It has dimensions of 2.5 meters in length, 1.5 meters in diameter, and a span of 4 meters. The satellite weighs 661 kilograms both at launch and dry mass. Its shape consists of a cylindrical body with a conical section. CAT 4 is powered by batteries and was manufactured by AERIT/CNEST. It operated for only 6 days in orbit.
Physical Characteristics

Length

2.5

Diameter

1.5

Span

4

Dry Mass

661

Launch Mass

661

Shape

Cyl + Cone

Radar Cross Section

2.6809

Visual Magnitude

Unknown

Color

Unknown

Material Composition

Unknown

Technical Details

Payload

CAT 04/VID

Purpose

Vehicle evaluation

Mission

Vehicle evaluation

Manufacturer

AERIT/CNEST

Life Expectancy

6 days

Bus

CAT

Configuration

Unknown

Motor

None

Equipment

Unknown

Power System

Batteries

ADCS

Unknown

Transmitter Frequency

Unknown

Map
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