The Story Behind the Mysterious Fireball Spotted in Western US

— -- A mysterious white light seen streaking across the night sky in the western U.S. was revealed to be debris from a Russian rocket, according to military officials.

When the bright fireball was first caught on camera in areas in Nevada and California, some speculated it was a meteor or shooting star.

The fireball was actually an SL-4 rocket booster from Russia that launched Monday, U.S. Strategic Command spokeswoman Julie Ziegenhorn told the Associated Press. The debris was caught on camera when it re-entered the atmosphere.

In November, another mysterious streak of light seen in southern California was revealed to be an unarmed missile test. The Pentagon said it was a scheduled missile test flight conducted at sea from the USS Kentucky. The missile was not armed and the tests were part of a scheduled and ongoing system evaluation test.

The Associated Press contributed to this report.