MICROSAT 2 (21581)

COSPAR: 1991-051B | Alt Name: Microsat 2

DECAYED

Image

Additional Sources

Launch Details

Launch Date

July 17, 1991

Launch Site

AFWTR

Launch Pad

RW04/22

Launch Vehicle

Pegasus/HAPS

Orbital Elements

NORAD ID

21581

International Designator

1991-051B

Decay Date

1/23/1992

Basic Satellite Info

Name

MICROSAT 2

Alternative Name

Microsat 2

Type

Payload

Status

Decayed

Owner

DARPA

Country

United States

Constellation

N/A

Related Satellites

Major Events

N/A

Summary

MICROSAT 2, also known as Microsat 2, is an experimental communication satellite with the OBJECT_ID 1991-051B and NORAD_CAT_ID 21581, launched by DARPA on July 17, 1991, from AFWTR using a Pegasus/HAPS launch vehicle. This US-manufactured Picostar spacecraft has dimensions of 0.2 meters in length and 0.5 meters in both diameter and span, with a dry mass of 19 kilograms and a total launch mass of 21 kilograms. It was equipped with a 1 UHF transponder digital store and forward communications system for its mission purposes. The satellite utilized solar cells and batteries for power and featured cold gas N2 propulsion. Although planned for a four-year lifespan, MICROSAT 2 only achieved an operational life span of one year.

Physical Characteristics

Length

0.2

Diameter

0.5

Span

0.5

Dry Mass

Launch Mass

Shape

Cyl

Radar Cross Section

0.21

Visual Magnitude

Unknown

Color

Unknown

Material Composition

Unknown

Technical Details

Payload

Microsat 2

Purpose

Experimental communication

Mission

Experimental communication

Manufacturer

DSI

Life Expectancy

4 years (planned); 1 year (achieved)

Bus

Picostar

Configuration

PicoStar

Motor

Cold gas N2 propulsion

Equipment

1 UHF transponder digital store and forward communications system

Power System

Solar cellsm batteries

ADCS

Unknown

Transmitter Frequency

Unknown

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