The near-earth region of space is now our backyard, and our backyard makes money for us. Every moment of the day, there are international telephone and television signals streaming into space, to be relayed back down anywhere on the globe.

But that is not all – there are also earth resources satellites watching the ground.They can record floods, veld fires or other natural disasters, and they also monitor and measure such diverse factors as the position of fish schools in the sea, the extent of desert encroachment, the extent of human settlements, and the nature of developed farmland.

With the aid of filters and electronic gear, satellites can even detect alien vegetation in the Kruger National Park. Plants that are not supposed to be there show up as different colours when different filters are used.

This information streams into the Satellite Applications Centre (SAC), at Hartbeeshoek, not far from Pretoria.

The people at the SAC also send instructions to satellites, and they even assist in the launch of rockets into space.

As a rocket leaves its launch pad somewhere on the other side of the planet, the earth rotates so that the rocket, racing overhead, comes into the area of coverage of the satellite dishes at Hartbeeshoek, which then control the rocket as it roars into space.

But right now folks around the country are waiting with excitement for the launch of the second South African-built satellite, SumbandilaSat. Sumbandila means ‘lead the way’ in the Venda language.

SumbandilaSat is going to be riding up into the heavens on top of a Russian Soyuz rocket. The satellite was carefully transported from Stellenbosch to the Baikonur space base, in Kazakhstan, where it is being installed into the rocket.

SumbandilaSat is important in the history of space in that, like its predecessor, SunSat, it was developed and constructed as a collaborative effort between staff and students at the University of Stellenbosch.

SumbandilaSat was designed and built in record time by specialist South African microsatellite company SunSpace & Information Systems, which is based in Stellenbosch. With support from the Department of Science and Technology (DST), this specialist company was spun off the engineering faculty of the University of Stellenbosch, the same people who built South Africa’s first satellite, SunSat.

SunSat was launched in 1999 and performed better than anyone had hoped for. SumbandilaSat is bigger and better. The new satellite weighs 81 kg and is about 1 m x 0,5 m in size.

Okay, so what can SumbandilaSat do? It has a camera, which is actually a multispectral imager comprising a set of sensors viewing different colours, or wavelengths, of the electromagnetic spectrum, to use the formal wording. This camera can view a stretch of ground some 45 km wide and has a resolution of 6,25 m, which means that it can see something about the size of a car.

As the satellite orbits overhead, each orbit does not cover the same strip of the earth that it would have passed over before, but SumbandilaSat can view the same strip five days later. This means that, if some time-sensitive event is occurring, such as a flood, or something much slower, such as the harvesting of crops, it is possible to look at the same piece of land every five days to monitor what is going on.

SumbandilaSat is designed to orbit at a height of 510 km, and this is rather far, bearing in mind that the satellite is about the size of a fridge. From that distance, it has to constantly communicate with the ground in South Africa.

About two months after the satellite has been launched, the Russians will hand over full mission control to the people at the SAC, where SunSpace will make all the scientific decisions about the mission while the people at the SAC execute the actual command and communications functions. This is done by tracking the satellite using a large dish antenna.

Amateur radio enthusiasts will also be able to tune in to the satellite because it has a special amateur radio transponder on board.

The design and construction of SumbandilaSat is an achievement that all South Africans can be proud of. The DST supported this venture for a variety of reasons. This space mission has helped in the general development and growth of people and institutions in South Africa, at a time when space is a commercial frontier.