Indonesia’s Sinabung volcano erupted on the morning of Monday, February 19, sending a cloud of ash and steam over part of the Karo Regency in North Sumatra.

Indonesia’s Center for Volcanology and Geological Hazard Mitigation (CVGHM) issued a warning notice to aviators, saying that the ash cloud had reached almost 24,000 feet and was expected to blow east-southeast. Credit: Dindasurel26 via Storyful