Ominous cloud seen over Alaska sparks conspiracies.

A large worm-like cloud materialized this week over Alaska’s Lazy Mountain, igniting conspiracy theories and prompting an investigation — and explanation — from Alaska State Troopers. It happened around 7 a.m. Thursday, April 7, and photos show the streak of smoke resembled everything from a falling meteor to a burning aircraft. Social media explanations included talk of an eruption, a crashing UFO and a Russian weapon linked to the ongoing conflict over Ukraine.

“We saw this on the way to school this morning as well. Very eerie!” Christy Hronkin Swift wrote on the Palmer Alaska Buzz Facebook page. “Looks like a meteor. I wonder where it landed,” Cassi Joi posted.

“Could it be a satellite? It’s so strange,” Shannon Del Vecchio Watson said. “No wings,” Susie Kuke Martin noted.

Rumors of a possible plane crash eventually caught the attention of Alaska State Troopers and the Alaska Rescue Coordination Center. “There have been no reports of overdue aircraft or ELT activations indicating an aircraft crash. A rescue team on a helicopter flew a mission around the Lazy Mountain area this morning and located nothing suspicious and there were no signs of crashed aircraft,” Alaska State Troopers reported in a release.

Instead, officials offered a rather simple explanation for the jaw-dropping sight. “Further investigation revealed that a large commercial jet was flying in that area around the time that the photos and video were taken. The aircraft was contacted and reported normal flight operations on its way to JFK airport in New York. Troopers believe that the photos and videos showed a contrail from the commercial jet combined with the rising sun which together caused the unique atmospheric sight.” Commenters on social media immediately began trying to poke holes in that explanation, with some suggesting a government cover up of an UFO crash and/or secret weapons testing. “The old swamp gas reflecting light from Venus story,” one man wrote. “Mermaid Man and Barnacle Boy could have come up with a better story than this,” another said.

But Eddie Zingone, a meteorologist with the National Weather Service in Anchorage, told the Anchorage Daily News that his best guess is “it was just a very vivid contrail.” “First of all, how thick it is on one side — the bottom left part is much thicker, which is what we’d expect,” he told the newspaper.