Airlines and Astronomers Grapple to Share Africa’s Skies


Skift Take

There’s a dark irony in the fact that, when planning the world’s largest radio telescope, nobody thought to look up. Now, astronomers and airlines in South Africa are battling to find a way to keep the skies quiet and air traffic flowing smoothly.

The construction of the Square Kilometre Array (SKA) in South Africa has become a feather in the cap of the country’s scientific community. When completed in the mid-2020s the SKA will become the world’s largest radio telescope, with 197 dishes searching for faint radio signals from distant stars and galaxies. South Africa’s sparsely populated Northern Cape province, near the town of Carnarvon, seems like the perfect location for this international scientific endeavor: sprawling sheep farms separate towns that are small and far-flung, keeping radio interference to a minimum. Except, ironically, nobody thought to look up. Above Carnarvon at 35,000 feet is the busiest patch of airspace in Africa. Flights between Cape Town and Johannesburg — the world’s 11th-busiest domestic route — travel overhead more than 50 times a day, along with private aircraft, cargo jets, and international traffic from the Middle East and East Africa. All of which adds up to a cacophony of ra