What is a CubeSat?

The 'U' Form Factor

CubeSats are a class of nanosatellites (satellites with masses between 1 and 10 kilograms) that use a standardized size and form factor called a "U" (a cube measuring 10 x 10 x 10 cm). A standard cubesat is 1U (10 x 10 x 10 cm), but using "U's" as a building block, larger sizes and arrangements can be achieved, such as 2U (10 x 10 x 20 cm), 3U (10 x 10 x 30 cm), 6U (10 x 20 x 30 cm), and so on.

Common CubeSat configurations (image: NASA)

Missions

CubeSats were originally developed by California Polytechnic State University at San Luis Obispo (CalPoly) and Stanford University in 1999 as an educational tool for students to learn about space systems engineering. Although initially conceived as a purely academic tool, the low-cost, standardization, and flexability of CubeSats has lead to their adoption by academia, the private sector, and governments for a variety of missions. Common applications include low-cost science missions, technology demonstrations too risky to justify a larger satellite, amateur radio communication, and remote-sensing of the Earth's surface.

Some examples of past CubeSat missions (Left to Right): The Vermont Lunar CubeSat, a 1U technology demostration CubeSat from Vermont Technical College (image: VTC); a PlanetLabs SuperDove satellite, a commercial 3U-CubeSat for Earth imaging (image: PlanetLabs); Mars Cube One A and B (MarCO-A and MarCO-B), two 6U-Cubesats from JPL that flew by Mars in support of NASA's InSight mission (image: NASA).

Since the first missions launched in June 2003, over 1600 CubeSats have been placed into orbit. Unitl recently, CubeSats were restriced to Low Earth Orbit (LEO). However in 2018, the two-CubeSat Mars Cube One (MarCO) mission became the first CubeSat mission to move beyond LEO, flying by Mars in support of the NASA's InSight mission. NASA's Artemis 1 mission will carry ten CubeSats to the Moon and beyond on the maiden flight of the SLS.

Launch

Due to their small size, CubeSats are typically carried into orbit as secondary (or rideshare) payloads on a launch. The Poly-PicoSatellite Orbital Deployer (P-POD) provides a mechanism for CubeSats deployed from the rocket's upper stage after orbital insertion. Alternatively, the NanoRacks CubeSat Deployer (NRCSD) allows for CubeSats to be carried to the the International Space Station inside Commercial Crew Resupply Vehicles (SpaceX Dragon and Northrup Grumman Cygnus) and deployed into orbit from the station's scientific airlock. In the last few years, several dedicated rocket launchers have been developed in which launch CubeSats as the primary payload, including the RocketLab Electron and Virgin Galactic LauncherOne.

(Left) Virgin Galactic's LauncherOne, (Right) RocketLab's Electron (images: NRO, Virgin Galactic).

Further Information

NASA

CalPoly CubeSat Laboratory

Canadian Space Agency