Space Brief 28 Aug 2025
Today's briefing covers collaborations enhancing defense capabilities, new satellite technologies entering the market, and strategic shifts in military satellite applications.
MICROSAT 7 (21586)
COSPAR: 1991-051G | Alt Name: Microsat 7
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
21586
International Designator
1991-051G
Decay Date
1/23/1992
Basic Satellite Info
Name
MICROSAT 7
Alternative Name
Microsat 7
Type
Payload
Status
Decayed
Owner
DARPA
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Summary
MICROSAT 7, also known as Microsat 7, is an experimental communication satellite owned by DARPA and manufactured by DSI. It was launched on July 17, 1991, from AFWTR using a Pegasus/HAPS launch vehicle from pad RW04/22. The satellite uses a Picostar configuration, measures 0.2 meters in length with a diameter and span of 0.5 meters each, and has a dry mass of 19 kg. Equipped with solar cells and batteries for power, it includes a 1 UHF transponder digital store and forward communications system for communication purposes. The satellite uses cold gas N2 propulsion and is cylindrical in shape. Its planned lifetime was four years but only achieved one year.
Physical Characteristics
Length
0.2
Diameter
0.5
Span
0.5
Dry Mass
19
Launch Mass
21
Shape
Cyl
Radar Cross Section
0.3175
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Microsat 7
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
Satellite Articles
View All Posts »Learn more about satellites and other related topics.
Neil Gehrels Swift Observatory
Designed for a two-year mission to catch gamma-ray bursts in the act, Swift is now 21 years old, slowly falling out of the sky, and the subject of an unprecedented private rescue mission. Nobody planned for it to be this hard to let go.
The Day Space Station Crews Gained Their Window on the World
Fifteen years ago, Space Shuttle Endeavour launched on a mission that would give International Space Station astronauts their most spectacular view of Earth through the innovative Cupola observatory
Artemis 2 Delayed by Upper Stage Issue, Falcon 9 Hits 33rd Flight | KeepTrack Space Brief
NASA delays Artemis 2 for SLS upper stage fix and pad rollback. SpaceX Falcon 9 booster shatters reuse record with 33rd flight. Tory Bruno joins Blue Origin for defense work.
SpaceX Starfall Reentry Capsule Makes Debut Flight | KeepTrack X Report
SpaceX's secretive Starfall reentry demo launched June 23 as Starmind AI constellation targets 1M orbital compute nodes.
Starship Flight 12 Targets May 19 with Redesigned Ship | KeepTrack X Report
SpaceX targets May 19 for Starship Flight 12 debut, while CRS-34 delivers 6,500 lbs of cargo to ISS aboard a Falcon 9.
The Dog They Never Planned to Bring Home
On April 14, 1958, Sputnik 2 burned up over the North Atlantic, carrying the remains of a stray dog from Moscow who had been dead for five months. The Soviet Union told the world she survived for days. It took forty-five years for the truth to come out.
X Report 31 May 2025
SpaceX successfully launched the latest GPS satellite for the U.S. military, while the FAA has initiated a mishap investigation on a recent Starship test flight. CEO Elon Musk provided updates on the future of the Starship program, indicating ambitious plans ahead.