HOUSE OVERSIGHT 028510 Farther south in Mountain View, Skybox captures high-resolution imaging data from its first satellite in orbit as it prepares another 23 to launch in the coming years. Some things, though, can be shrunk only so far and larger satellites are needed for a telescope to obtain the higher resolutions required for the firm's analysis. While Skybox's minisatellites weigh around 100kg, a fairly common size for small satellites, the firm proved its concept to investors using CubeSats. "Being able to put something in space at very low cost allows you to demonstrate the technology to get more money," says Dan Berkenstock, one of the company's founders. The CubeSat specification came out of the academic world in the late 1990s. Bob Twiggs, then at Stanford University and now at Morehead State University, was frustrated by long delays on a large-satellite programme and set about thinking how much satellite capability might be crammed into a much smaller craft that could be launched cheaply. Space launches usually comprise one or more primary payloads and require ballast to balance the rocket. CubeSats, reasoned Mr Twiggs, could take the place of some of this ballast, so long as they did not jeopardise the main mission. The optimum size Mr Twiggs came up with was based on a box used to display Beanie Babies. Later, with Jordi Puig- Suari of California Polytechnic State University, it was turned into a full specification. Mr Twiggs also developed the 5cm PocketQube, which has a maximum weight of 180 grammes. Small satellites benefit from the constant improvements in price and performance being achieved by the consumer- electronics industry, particularly in smartphones. A typical phone is now likely to contain an accelerometer to measure how fast it is moving, a magnetometer to detect magnetic fields and provide a compass reading, a GPS receiver to pick up satellite data, multiple radios, a gyroscope to measure its position, a barometer to det