The low-orbit Sumbandila-Sat will be launched on top of a Russian Soyuz rocket in Kazakhstan just before 6pm.
The Science and Technology Department invested R26-million in the project which was spearheaded by Stellenbosch University's engineering faculty.
The same engineers created the pioneering SunSat, launched in 1999.
Professor Herman Steyn said the earth observation satellite would be an eye in the sky.
It will provide information for a range of applications from the effective management of disasters to food security and the use of water resources.
Steyn said the satellite would enter our skies about two and a half hours after blast off.
"Tonight the satellite will appear for the first time and it will be visible for about 10 minutes and we will be able to communicate with the satellite during that time."
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