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The Satellite Centre at Surrey has 8 microsatellites that orbit above the equator at 970 km above the Earth. They are equally spaced and their 'footprints' overlap to ensure the whole Earth is covered. Find out more about six of our missions...
Some satellites are in Low Earth Orbit (LEO) at a height of only about 700 km above the Earth's surface. They orbit over the pole once every 100 minutes approximately and can see a different segment of the Earth as it spins beneath the satellite. All of the satellites are continuously monitored by Mission Control at Surrey Space Centre as they pass over head at 7.5 km/s. This makes sure each one is in the correct orbit and attitude (orientation) and allows the scientists to download any data the satellite has taken in its journey around the earth. Each pass lasts only 10 - 20 minutes before the satellite is again out of reach. Communications satellites such as those that transmit television signals, are in geostationary orbit. They go round the equator once in 24 hours. This is how they remain above the same spot on the Earth all the time. These travel much more slowly than LEO satellites and are about 36000km above the Earth's surface. |
Orbit: Store and Forward microsatellite uploads an email from a small terminal on the ground. This could be a Doctor in a remote location or an automated terminal monitoring an oil pipeline. The microsatellite can also deliver messages to remote users. The terminals are small and can be readily accommodated in a boat, truck or car. Inexpensive fixed-groundstations are used to relay messages via networks or the Internet for faster delivery. SSTL's Store and Forward system has been used to quickly route messages between Doctors in Africa and hospitals in the UK and the US. The SSTL Store and Forward System uses Low Earth Orbits to provide global coverage and short periods between revisits. It is suited to provide Electronic Mail Services for remote regions and military and national security. |
