CubeSat

A CubeSat (U-class spacecraft) is a type of miniaturized satellite for space research that is made up of multiples of 10×10×11.35 cm cubic units. CubeSats have a mass of no more than 1.33 kilograms per unit, and often use commercial off-the-shelf (COTS) components for their electronics and structure. CubeSats are most commonly put in orbit by deployers on the International Space Station, or launched as secondary payloads on a launch vehicle.

In 1999, California Polytechnic State University (Cal Poly) and Stanford University developed the CubeSat specifications to promote and develop the skills necessary for the design, manufacture, and testing of small satellites intended for low Earth orbit (LEO) that perform a number of scientific research functions and explore new space technologies. Academia accounted for the majority of CubeSat launches until 2013, when over half of launches were for non-academic purposes, and by 2014 most newly deployed CubeSats were for commercial or amateur projects. CubeSats have been built by large and small companies alike, while other projects have been the subject of Kickstarter campaigns.

Uses typically involve experiments which can be miniaturized or serve purposes such as Earth observation or amateur radio. Many CubeSats are used to demonstrate spacecraft technologies that are targeted for use in small satellites or that present questionable feasibility and are unlikely to justify the cost of a larger satellite. Scientific experiments with questionable underlying theory may also find themselves aboard CubeSats as their low cost could justify riskier experiments. Biological research payloads have been flown on several missions, with more planned. Several missions to the Moon and Mars are planned to use CubeSats.

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