On September 8, 2012 the San Cristóbal volcano erupted three times, shooting a column of ash and gas high into the sky over Nicaragua, and prompting evacuation of about 3,000 citizens. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite captured this true-color image at 19:20 UTC (1:20 p.m. local time). In this image, tan-colored ash can be seen rising from the area of the volcano in northern Nicaragua and filling the skies to the northwest over Honduras, and then blowing to the southwest over the Pacific Ocean.
The height of the early morning eruption produced an ash column that may have initially risen up to about 32,000 feet (10 km) altitude, or about 8 km above the crater. The ash column later decreased and fluctuated between 1.5 and 5 km in height, according to Volcano Discovery. The ash fall covered an area of about 2,438 sq. km, primarily distributed in the west-northwest and up to approximately 50 km from the caldera. The maximum ash fall deposit was reported to be 5 inches in areas very close to the crater.
Since the eruption San Cristóbal has been relatively quiescent, with intermittent weak explosions and small amounts of steam seen. The SO2 output has also been measured at elevated levels, but additional explosive eruptions are not immediately expected.
The volcano, also known as El Viejo, the highest and one of the most active in Nicaragua, has a history of small to medium-sized ash eruptions dating back to the 16th century.