Brought to you by: Hermanus Times
01/10/2009 02:01 PM – (SA)
South Africa and more particularly, the HMO (Hermanus Magnetic Observatory) have been engaged in an exciting space technology programme which resulted in the launch of the second SA satellite, Sumbandilasat, on 17 September from the Baikonur Cosmodrome in Russia.
This satellite was designed and built in SA by South Africans from the specialist microsatellite company SunSpace and Information Systems based in Stellenbosch. The R26 million satellite was funded by the department of science and technology. It is an 81 kg, 1×0.5 metres micro-satellite, and will orbit 500 kilometres above the Earth in polar orbit. It goes around the Earth in 100 minutes and will pass over South Africa four times a day. It is an imaging satellite and will produce images for agricultural and environmental use by the government, primarily tracking climate change, human migration, crop estimates and forestry.
One of the key components in the successful operation of a satellite is the ability to control its attitude and orientation so that it’s imaging cameras and antennas are accurately pointed towards the Earth at all times. On Sumbandilasat orientation sensing is effected by, among other things, a combination of a star camera and a three-axis fluxgate magnetometer.
The magnetometer allows the satellite control system to align the satellite with the Earth’s magnetic field at each point in its orbit. The HMO built the sensors for the Sumbandilasat magnetometer and performed the final calibration of the magnetometer, after integration of the sensors with the electronics built by SunSpace. The same sensor design, developed by HMO, was used for South Africa’s first satellite, Sunsat-1, launched in February 1999. For the first launch the HMO also built the electronics for the magnetometer. The same type of sensor has also been used on several other satellites since then. The HMO also has a VLF (very low frequency) wave experiment designed by Dr Andrew Collier, a research scientist at HMO, on board Sumbandilasat. This space weather instrument is a tool for space physics research and will enable scientists to listen to radio signals in space caused by lightning. Listen to VLF signals from space and read more about them at: http://spaceweather.com/glossary/inspire.html .
As part of World Space Week from 4 to 10 October, Jan-Albert Koekemoer, chief systems engineer at SunSpace, the company in Stellenbosch that designed and built Sumbandilasat, will give a public lecture at the HMO on Thursday, 8 October at 19:00. Call 0n 028-312 1196 to confirm your attendance.