Yellowstone National Park has long captured the imagination of scientists and the public alike, particularly due to its supervolcano, which has featured prominently in disaster films and existential musings.

A park scientist noticed it about two weeks after a hydrothermal explosion along a boardwalk during the park’s overactive summer.

According to the Associated Press, scientists first saw the column of steam in the summer of 2024. Upon closer inspection, they determined that the plume’s temperature was 171℉, and that it was relatively new based on a thin layer of gray clay surrounding it.