The Glowing Spiral over Khartoum

At 01:00 UTC on 8 January 2018, a SpaceX Falcon 9 lifted off from Cape Canaveral. On board was Zuma, a classified US satellite catalogued as USA-280. About two hours and fifteen minutes later, something lit up the sky over Sudan.

Peter Horstink was flying Martinair flight MPH8371 from Amsterdam to Johannesburg. A Boeing 747-400 freighter. Just north of Khartoum. 35,000 ft.

"It started with a greenish light in the top of my front window," he wrote. At the centre was "a point of light (like a star but somewhat bigger)". It moved more slowly than a typical satellite, from above the aircraft towards the south. "The object was surrounded by a greenish glow in the shape of spiral arms, like a spiral galaxy." He judged the whole thing at about three times the diameter of the moon. He watched it for two to three minutes. He photographed it.

On the ground, people saw it too. Al Arabiya described a luminous body surrounded by a radiant green light. IBTimes reported that many residents feared an "alien invasion". Abdelrahman Osman said he saw it himself and that a friend took a picture. Sam Cornwell shared a ground photo: "Seen at 515 over Sudan. Timeline matches up for Zuma."

The Sudanese military issued a statement that same morning. Its base at Omdurman had been alerted by nearby stations to "a bright body flying at low altitude" over the Wadi Sayidna military zone. Forces were put on extreme readiness to intercept a possible photographic reconnaissance vehicle. The statement called the object a "suspected" satellite. It admitted the object had not been identified.

On 9 January, Dutch satellite tracker Marco Langbroek of SatTrackCam Leiden published his analysis. Measured against the background stars, the spiral in Horstink's photo was about 11 degrees across and about 8 degrees above the horizon, in the south-south-east near Alpha and Beta Centauri. The waning Moon stood almost overhead. Langbroek placed the sighting at about 03:18 UTC.

The time, direction and shape matched the Falcon 9 upper stage of the Zuma launch. In his reading, it was "almost certainly" the stage venting leftover fuel at the end of its de-orbit burn, at roughly 200 to 400 km. Re-entry was expected 15 to 25 minutes later, over the southern Indian Ocean. He stressed that venting is routine and not necessarily a sign of failure. He compared it to a similar spiral seen after a 2010 Falcon 9/Dragon test launch.

Much of the press reported that the satellite itself was venting fuel. Langbroek's own analysis pointed to the upper stage. The general mechanism is well described. Fuel dumped from a spinning stage freezes into ice crystals that catch sunlight at high altitude while the ground below is still dark. The spin draws the spiral.

Zuma's own fate became a story of its own. Two independent investigations tentatively concluded that the payload never separated from its Northrop Grumman adapter and re-entered with the stage. SpaceX called its rocket's performance "nominal".

The Khartoum spiral now sits in Wikipedia's list of UFO sightings in Africa, and Sputnik Africa included it in a 2023 World UFO Day roundup. It also belongs to a growing family of rocket spirals: the Norway spiral before it, then Falcon 9 spirals over Hawaii and New Zealand in 2022 and over the UK and Europe in March 2025. For one pilot over Sudan, though, it began as a green light at the top of his window.