Educatif issues, par Hubert Reeves
industry issues, by l’ESA
The nanosatellites developed at the University Space Centre are called CubeSats:
What is a nanosatellite?
Compared to a large commercial satellite, a nanosatellite is a small satellite that can test new technologies and collect data in space (environmental observation…) rapidly and at low cost. Once the validated technology is in orbit, it can subsequently be developed without risk for big satellites. In the same way as for mobile phones, miniaturisation linked to the technology’s evolution leads to the development of increasingly efficient applications.
Nanosatellites of the 1Unit CubeSats type
Size: 10cm profile
Mass : 1 kg
Volume : 1 Litre
They rotate as they orbit the Earth (non-stabilised).
These characteristics are compatible with standard CubeSat containers called “deployment systems” which enable them to be propelled into space from launchers.
Nanosatellites of the triple CubeSats 3Units type
or the equivalent of three stacked CubeSats.
These nanosatellites can stabilise to point the solar panels towards the sun, observe a point on the globe or in space, and direct their antennae towards the ground station.
What is a nanosatellite made of?
A CubeSat carries a science experiment called a “payload”.
The rest of the satellite that allows it to operate is called “the platform”.
All the elements that allow the nanosatellite to operate: the mechanical structure, the ‘OBC’ on-board computer (the nanosatellite’s brain), the ‘EPS’ production and energy storage system (solar panels, battery, management card…), and a telecommunications system (antennae, emitter/receiver…). Some CubeSats, especially the 3Units, are also equipped with an attitude control system for precise pointing in space.
The payload, or experiment:
Equipment inside the platform, specific to each mission, that will perform the experiment (test of tolerance to radiation, data transfer, observations…).
Life of nanosatellite in space
Space is a hostile environment. The nanosatellite must survive there during the whole mission. After being subjected to very strong vibrations at the rocket’s take-off, it must also resist very high temperatures from the sun, extreme cold in the shade, extremely aggressive space radiation, and the challenges of the void of space – which prevents thermal exchange by convection and produces degassing (e.g.: the slightest bubble imprisoned in the glue will swell and burst a solar cell).
Its mission over, or in the event of a break-down, no question of it forming debris that could damage other satellites or cause pollution in space. It therefore has to come back down to earth and combust when re-entering the atmosphere. All of our nanosatellites comply with the L.O.S. law relative to space operations, which ensures the sustainable development aspect..