Small Satellites
The Beginning of the Small Satellite Era
Humankind successfully sent its first artificial satellites into the Earth’s orbit in 1957, with the USSR’s Sputnik models. Since then and up until the end of the 20th century, the world’s superpowers, led by their governments, launched hundreds of satellites, competing in a race to explore space in a series of increasingly ambitious and complex projects.
For many years, satellite mass increased: the first Sputnik weighed 80 kg and the second over 500. Today, the International Space Station has a mass of 420,000 kg. However, except for some military, astronomy, and specific communication applications, it seems that the era of massive satellites is over.
New Space is based on a philosophy of creating less expensive satellites in shorter periods of time, thanks to the falling costs and miniaturization of electronic parts. As a result, satellite launches are now accessible even for companies, universities, schools, and people on their own.
Why Nanosatellites
Apart from their size and cost, the biggest advantage of a nanosatellite is the short time period required to develop each model. An average-sized or large satellite requires between 5 and 15 years to identify the need and place it in the right orbit under normal parameters.
Between the start and end of operations, needs may well have changed, which means that the initially planned uses are no longer market-appropriate. What’s more, telecommunications technologies are constantly changing and being updated, which means that conventional satellites eventually end up operating with 15-year-old technologies. It is impossible to constantly update large satellites, which means that they cannot be modified even when a market or technology opportunity arises.
Depending on the specifications, a nanosatellite can be built and placed in orbit for 500,000 euros, while the cost of a conventional satellite can be as high as 500 million euros.
Launching a nanosatellite as part of a constellation, furthermore, allows for the risk involved in any space mission to be divided up amongst smaller segments. In contrast, the failure of a large-scale satellite may well jeopardise the entire mission.
As a general rule, nanosatellites are launched in low circular or elliptical orbits (altitudes of between 400 and 650 km) and travel at around 8 km per second. At this altitude and height, it takes them around 90 minutes to orbit the Earth, completing between 14 and 16 orbits a day. These conditions are ideal for nanosatellites. By orbiting closer to the Earth, they not only guarantee optimum conditions for land observation or communications, but are also better protected from solar and cosmic radiation.
The CubeSat Standard
CubeSats are a class of nanosatellites that use a standard size and form factor. The standard CubeSat size uses a "one unit" or "1U" measuring 10x10x10 cms and is extendable to larger sizes; 1.5, 2, 3, 6, and even 12U. Some companies have produced standards up to 27 U. At the same time, smaller picosatellites, the so-called PocketQubes, about 1/8 the size of a CubeSat, have also been standardized.
Originally they were developed in 1999 by California Polytechnic State University at San Luis Obispo (Cal Poly) and Stanford University to provide a platform for education and space exploration. The development of CubeSats has advanced into its own industry with government, industry and academia collaborating for ever-increasing capabilities. CubeSats now provide a cost-effective platform for science investigations, new technology demonstrations and advanced mission concepts using constellations, swarms disaggregated systems.