SpaceX launched the SAOCOM 1A satellite from California Sunday night, most likely responsible for sending a bright streak of light across the Valley sky.
Watch the launch in the player below.
The launch happened at the Vandenberg Air Force Base in California around 7:30 p.m. The launch was reported as successful.
Los Angeles Mayor Eric Garcetti was among those trying to clear up the speculation, tweeting a photo of the launch and writing: "Nope, definitely not aliens."
The primary purpose of the SpaceX mission was to place the SAOCOM 1A satellite into orbit, but SpaceX also wanted to expand its recovery of first stages to its launch site at Vandenberg.
SpaceX had previously flown first-stage rockets back to land after Florida launches but had not done so on the West Coast.
SpaceX also has successfully landed Falcon 9 first stages on so-called drone ships off the coasts of Florida and California, all as part of its effort to decrease the cost of space launches by reusing rockets rather than allowing them to fall into the ocean.
The satellite is the first of two for Argentina's space agency, the Comision Nacional de Actividades Espaciales, and will work in conjunction with a constellation of Italian space agency satellites. Its acronym is short for Satelite Argentino de Observacion Con Microondas.