High-Resolution Image

On June 12, 2009, astronauts onboard the International Space Station took a photo of the Sarychev Volcano erupting as it passed overhead. Sarychev Peak is a large Stratovolcano (a highly explosive, multilayered volcano with strata composed of solidified volcanic ash, tephra and lava, that is usually found around subduction zones) that has had its most recent eruptions in 1960, 1965, 1976, 1986 and 1989. The photo on the top left shows the cloud of ash and steam erupting from the volcano. Ash from this eruption has been found up to 2,407 kilometers east-southeast and 926 kilometers west-northwest of the volcano and has disrupted air traffic between Eastern Asia and North America. The photo on the top right shows the concentrations of the SO2 column as the aerosols moved away from the erupting volcano.

The eruption of Sarychev also led to worldwide colorful sunsets. This phenomenon occurs when the ash and fine particles sprayed high into the atmosphere by the volcano scatter light. The sulfur dioxide ejected by Sarychev Peak interacts with gases in the atmosphere to form tiny particles called sulfate aerosols. Usually, particles in the atmosphere scatter short wave blue light, so that people on the Earth’s surface see a blue sky. The excess particles in the atmosphere due to volcanoes make it more difficult for the sun’s rays to travel to our eyes. This allows long wavelength red light to reach us, which intensifies the coloring of the sky that we see. These colors are usually seen post-sunset and are called afterglows.

Submitted by Ashley Griffin (SSAI and University of Maryland College of Computer, Mathematical and Physical Sciences); Lorraine Remer (NASA Mentor).