Cube satellites, or “cubesats” are small spacecraft built in units of 10x10x10cm cubes. The standard size and form factor was developed in 1999 by researchers at Stanford University and Cal Poly in order to increase the number of spacecraft that were being launched into space. The standardization has been greatly successful, enabling the launch of hundreds of small spacecraft in the past several years, and the number of vehicles being launched continues to increase. The launches per year is being tracked by M. Swartwout and is posted online. The most common sizes are 1U, 3U, and 6U.
The increased access to launch opportunities has provided governments, universities, and corporations the ability to demonstrate developing technologies in space as well enable new types of science experiments. The deployment of a 3U cubesat from the international space station is shown below.