At first there were the small satellites. The reason was very prosaic: early rockets simply weren't powerful enough to launch more than a few then kilos to Earth orbit. The Sputnik-1 with its 84 kg and 61 cm diameter sphere was a real monster compared to the first American attempts, the 1.5 kg, grapefruit-sized (and mocked) Vanguard-1 or the 14 kg Explorer-1. Capacities expanded rapidly of course and in a short few years launching a human in a spacecraft wasn't a problem any more. Satellites and space probes grew more and more large and complex and entire space stations were orbiting the Earth. But small ones remained throughout to carry out one or two selected experiments or tasks.

But size was the only real difference: be tiny or enormous, they were built slowly and costly, often topped with overcomplicated management. And to assure success and return of investments, specialized and expensive space-rated hardware was used that lagged behind commercial products as much as 10-15 years in capacities. So the question remains: is there another, cheaper and faster way to reach space?

Read our summary written by László Molnár on the development of small satellites here.

By the way, we are considering our own TubeSat project and are working on a feasibility study right now. But more about that later!

CubeSats among themselves: the AeroCube-2 shot this picture of Cal Poly's CP4 with its miniature camera right after ejection to orbit. (Image credit: Aerospace Corp.)