The M9-class solar flare was observed by Nasa's Solar Dynamics Observatory and erupted from a sunspot on Monday at 05:59, SpaceWeather.com reported.
The coronal mass ejection or CME is travelling to Earth at 2 200km/s which means that it could potentially cause communications disruptions to networks on the planet that could include disabling satellites in its path.
In the polar regions people could observe spectacular auroras, that may even be visible at lower latitudes.
The CME may have a particular impact in South Africa because of the South Atlantic Anomaly where the Earth's magnetic field is weakest.
The CME is scheduled to hit at about 16:18 on Tuesday and South Africans should take care to avoid being exposed directly to the sun.
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