[SatNews] A month and a half of continuous eruption has left the caldera of Veniamanof Volcano, one of the largest on the Alaskan Peninsula, coated with ash. Variable winds carried ash away from the eruption vent, leaving a radial pattern of dark streaks. The ash carpeted the ice-filled caldera and the surrounding glaciers and snowfields. Three separate small plumes—one ash-rich and two steam-rich—rose from a 300-meter (1,000-foot) high cinder cone near the western rim of the caldera and the aptly-named Cone Glacier. This natural-color Landsat 8 image of Veniamanof (top) was collected on July 25, 2013.

Sixteen days earlier (lower image), on July 9, much less ash was visible. It is likely ash from earlier stages of the eruption was hidden by fresh, brilliant white, snow. Over the next two weeks much of the snow melted during the long summer days (accelerated by the presence of the ash itself), and additional ash accumulated as the eruption continued.

The Alaska Volcano Observatory originally detected an eruption at Veniamanof on June 13, 2013. On July 25 the observatory reported volcanic tremor, high surface temperatures, and nighttime glow. These signals indicated “an ongoing low-level eruption characterized by intermittent effusion of lava and emission of minor amounts of ash and steam.”