When the US aerospace agency brings a plane to zig-zag over a fault line that could conceivably bring doom to the American West Coast, there must be a reason. But which one exactly? Internet users are getting suspicious.

A NASA aircraft spotted flying over California last week has sparked fears that the aerospace agency knows something that it is not telling, The Daily Star reported Monday.

According to the report, Internet users surprised at the sight of a registered NASA plane NASA817 – a venerable Douglas DC-8 – transiting the skies above California, took to air traffic tracking websites to discover the plane’s route is closely matching the notorious San Andreas Fault.

The plane’s track has zig-zagged back and forth along the fault line multiple times, leaving no room for a coincidence.

The heck? NASA flying low over California fault lines??https://t.co/0SFjAruhcd — Christopher Mantei (@mantei4) July 23, 2019

​The San Andreas Fault is a 750 mile-long boundary between two massive tectonic plates: the Pacific Plate and the North American Plate. For years, fears have circulated that a particularly big earthquake – nicknamed ‘The Big One’ - will erupt along the fault line, sparking a large tsunami that could drown entire swathes of the US West Coast.

NASA has not commented on the movement of the aircraft in the area, the Star report says.

Internet conspiracy enthusiasts did not miss an opportunity to make wild guesses as to the purpose of the overflight, with one YouTuber – Tyler Glockner of “secureteam10” channel - floating the possibility that the agency knows something about the dreaded monster earthquake that it is no hurry to disclose.

“A registered NASA aircraft was noticed doing zig-zag flying patterns near and over the San Andreas Fault line,” he said on a video. “It’s almost as if it is scanning the ground as if to try and get more data about what is happening underneath. What is going on? Is something occurring? What do they know, are they gearing up for something?”

Crazy flight path.



Call sign NASA817



Slow and low...like a snake over the fault and then BOOM fast as lightning to Boise, ID. https://t.co/Siyqh6Cy9h — Whats in a name (@Rustygirl2000) July 26, 2019

​Recently, California sustained two earthquake of approximate magnitude of 7. While no major injuries were reported in the wake of the incidents, the quakes did damage infrastructure, with the governor declaring a state of emergency to release funds to make quick repairs.

One commenter responding to Glockner’s video suggested NASA was surveying the fault line to check whether the two quakes caused any changes that the US government should be worried about.

Others, however, were more dramatic:

“The government has brought NASA in to see if they can predict when she will erupt because supposedly we are overdue for a Big One,” a commenter wrote.

At the time of the writing, however, the plane left California and is currently conducting a mission over Helena-Lewis and Clark National Forest in Montana.