The Shishaldin Volcano on the eastern edge of Alaska’s Aleutian Island chain erupted with activity in January of 2020.

The eruption on the island of Unimak sent an ash cloud five miles into the sky on January 7, forcing ash alerts for aviators, mariners and residents of nearby communities.

Landsat 8 captured both day- and nighttime imagery of the event as it happened. The first image in this series shows the volcano in August of 2019, a period of relative calm after a series of low-level eruptions the previous month.

A more explosive event began shortly after the new year. The island’s northern coast is just barely visible in the cloudy daytime image from January 7, but the satellite’s infrared and shortwave infrared bands capture the intensity of the Shishaldin’s eruptive heat as a flaming burst of red.

The nighttime image collected hours earlier is even more stark. The satellite’s thermal and infrared sensors depict the crater’s heat signature as a colorful orb. Zooming in, the heat signature is apparent.

Satellites such as Landsat are valuable tools to scientists studying volcanic activity from afar.