A colorful time-lapse video of Chile’s erupting Calbuco volcano is going viral this week after it was posted to YouTube.

Calbuco has been quiet for 42 years but erupted dramatically this week. The volcano in southern Chile towers over the city of Puerto Montt. (Here’s a photo of the mountain during a quieter period.)

The volcano emitted an ash plume that rose to an estimated 33,000 feet (10 kilometers), according to an observatory in Buenos Aires. Pyroclastic flows—hot, dense clouds of material that blast out of a crater at high speeds—and lava flows have been observed at the top of the volcano.

The volcano erupted with little warning, prompting the Chilean Geological Survey and the Chilean Emergency