Optical Intersatellite Link (OISL)
The laser-based crosslinks that turn Starlink into a mesh, anchor the SDA Transport Layer, and just made their GPS debut on GPS III SV10 - quietly rewriting how data moves through space.
FLOCK 4S-21 (47456)
COSPAR: 2021-006AV | Alt Name: Flock 4s-21
DECAYED
Image
Additional Sources
Launch Details
Launch Date
January 24, 2021
Launch Site
Launch Pad
LC40
Launch Vehicle
Orbital Elements
NORAD ID
47456
International Designator
2021-006AV
Decay Date
8/23/2024
Basic Satellite Info
Name
FLOCK 4S-21
Alternative Name
Flock 4s-21
Type
Payload
Status
Decayed
Owner
PLAN
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Summary
FLOCK 4S-21, also known as Flock 4s-21, is a CubeSat (3U) satellite manufactured by PLAN and launched on January 24, 2021, from the Cape Canaveral Air Force Station Launch Complex 40 using a Falcon 9 launch vehicle. The satellite has dimensions of 0.3 meters in length, 0.1 meters in diameter, and a span of 0.3 meters. It weighs 5.7 kilograms both at launch and dry mass. Equipped with PS0, PS1 or PS2 imaging payload (Dove 245c), the satellite's primary mission is technology demonstration. Its power source consists of solar cells and batteries, while its shape is described as a box with two panels. The expected lifetime ranges from about one year in International Space Station orbit to two to three years in Sun-Synchronous Orbit (SSO).
Physical Characteristics
Length
0.3
Diameter
0.1
Span
0.3
Dry Mass
5.7
Launch Mass
5.7
Shape
Box+2 pan
Radar Cross Section
Unknown
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Dove 245c
Purpose
Technology
Mission
Technology
Manufacturer
PLAN
Life Expectancy
~ 1 year (ISS orbit); 2-3 years (SSO)
Bus
Cubesat 3U
Configuration
CubeSat (3U)
Motor
None (most); FEEP (#Flock-3p')
Equipment
PS0, PS1 or PS2 imaging payload
Power System
Solar cells, batteries
ADCS
Unknown
Transmitter Frequency
Unknown
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