SA satellite heads to International Space Station


A nanosatellite developed by Stellenbosch University (SU) and CubeSpace, an Innovus incubation company in the Nedbank SU LaunchLab business incubator, is to be launched with 49 other nanosatellites from the International Space Station (ISS) in January.

The South African nanosatellite, ZA-AeroSat, weighing only 2kg, is the only satellite from Africa forming part of an international initiative, the QB50 project, to launch 50 nanosatellites known as ‘CubeSats’ – each about 10cm x 10cm x 20cm (smaller than a shoebox) – from the ISS to gather measurements from the lower thermosphere between 200km and 400km above Earth.

ZA-AeroSat will be taken to Delft in the Netherlands, where it will be packed with the other satellites before being shipped to the US and transported to the ISS in December.

The Electronic Systems Laboratory (ESL) in SU’s Department of Electrical and Electronic Engineering and CubeSpace, which arose from the ESL, have been working on this local nanosatellite for some time.

An event will be held at the LaunchLab on Friday, during which the satellite can be viewed for the last time and a short presentation of its capabilities will be given.

The QB50 project forms part of the atmospheric modelling research carried out by the European Space Agency to predict the results of space objects penetrating the earth’s atmosphere more accurately.

Since the ESL and, more recently, CubeSpace, are already widely recognised internationally for innovative small-satellite orientation control systems, they were asked to supply 15 control units (attitude determination and control systems) to other satellites in the QB50 project, says professor Herman Steyn, head of the project and founder of CubeSpace.
“They’re, therefore, helping out where other participants don’t have enough experience in satellite control systems. It’s a huge challenge to keep a satellite within 10 degrees of the orbiting direction,” he explains.

The 15 control units, fully developed within the ESL, together with some of the control system software developed with the Surrey Space Centre in England, were sent to the Von Karman Institute for Fluid Dynamics in Belgium for distribution to the selected project participants.

The first three control units were delivered to Innovative Solutions in Space, a satellite company in the Netherlands, early in 2014, which launched two QB50 satellites as a test run before the QB50 mission was announced in May 2014. The control units have successfully been operating in space on these test satellites for more than two years.

The funding received for these control units helped to sponsor Africa’s only satellite in the QB50 project. The Cape Peninsula University of Technology was involved in the development of the satellite’s communication modules.

Steyn says ZA-AeroSat will also be used to demonstrate the aerodynamic stabilisation of a satellite in practical terms for the first time.
“The antennas at the back of the satellite will be used like the feathers of a shuttlecock to give the satellite partial passive stability,” he points out. “This will be made possible by the greater atmospheric density in the low orbiting heights of QB50.”

The ESL/CubeSpace developed ZA-AeroSat’s on-board computer (CubeComputer) and the attitude control system (CubeSense and CubeControl) locally for use in space. The CubeSat components are also sold internationally online in the CubeSatShop and in Innovus’s online satellite component shop.

A newly-developed experimental star camera satellite sensor (CubeStar), weighing only 80g, will furthermore be flown to qualify it for use in space. An experimental gravitational wave sensor is also testing whether gravitational wave distortions caused by, for example, the position of the sun and the moon relative to the earth, can be determined.