Nyiragongo in the Democratic Republic of the Congo is one of the world’s most active and dangerous volcanoes. For most of the twentieth and twenty-first centuries, a lava lake has partially filled the 3,470-meter- (11,384-foot-) high summit caldera.
White steam and other volcanic gases (which contribute a bluish tint) rise from the surface of Nyiragongo’s lava lake in this natural-color satellite image. The image was acquired by the Advanced Land Imager (ALI) aboard NASA’s Earth Observing-1 (EO-1) satellite on May 28, 2010. It is likely that the dark gray/black area on the caldera floor is a crust of solidified lava, and the plume is emanating from the molten surface of the lake. Terraces on the caldera walls indicate the height of former lava lakes. Sharehu crater, about 2 kilometers (3 miles) south of the summit was the site of active fissures in both 1977 and 2002.
According to the Global Volcanism Program, 20 eruptions have occurred since 1884. Eruptions on the southeastern flank of the volcano in 1977 and 2002 drained the lava lake. During both eruptions extremely fluid lava flowed downslope at speeds up to 60 kilometers (40 miles) per hour, reaching as far as the city of Goma (population of approximately 250,000) 16 kilometers (10 miles) to the south. Estimates of casualties from both eruptions vary substantially. In 1977 there were from 38 to 70 deaths, and in 2002 there were 70 to 147 fatalities, including dozens killed by an exploding gas station in Goma.
This pair of high-resolution images from the commercial Ikonos satellite shows the craters of Nyamuragira and Nyiragongo, both of which are located at the far eastern edge of Democratic Republic of Congo, north of Lake Kivu.
In central Africa, in the Democratic Republic of the Congo, sit two volcanoes: Nyiragongo and Nyamuragira. Besides their proximity to Lake Kivu in the south, these volcanoes share the capacity for destruction, each having produced its share of catastrophic eruptions since the early twentieth century. Yet these volcanoes differ markedly from each other, one being a low-profiled structure rising subtly from the plain, and the other sporting steep slopes.