Rocket Fuel Dump Sparks Night-Sky Spiral Seen From U.S. East Coast to Ontario

Skywatchers from Massachusetts to Maryland and as far north as southern Ontario reported a bright, slowly changing white object in the night sky on 12–13 Aug. The sighting, which coincided with the peak of the annual Perseid meteor shower, prompted speculation of a UFO after videos showed a luminous, spiral-shaped cloud lingering high above the horizon. Meteorologists and space scientists said the phenomenon almost certainly came from routine launch activity rather than extraterrestrial hardware. WCVB’s chief meteorologist Cindy Fitzgibbon traced the U.S. East Coast display to a fuel-dump conducted during United Launch Alliance’s Vulcan rocket liftoff from Cape Canaveral earlier that evening. When unburned propellant vents into the upper atmosphere it freezes into ice crystals that reflect sunlight, creating a glowing halo sometimes called a “fuel spiral.” In Canada, York University astrophysicist Jesse Rogerson attributed a similar bow-tie-shaped plume to a spent stage from Europe’s Ariane 6 mission launched from Kourou, French Guiana a few hours earlier. Because both rockets were climbing to high altitudes, their exhaust clouds remained sun-lit long after local sunset and were visible hundreds of kilometres away. The U.S. Federal Aviation Administration said it records any pilot reports of unidentified aerial phenomena but had received no indications of a safety risk.