Earth from Space: Explosive land
This Envisat radar image features a chain of volcanoes called the Virunga Mountains that stretch across Rwanda's northern border with Uganda and east into the Democratic Republic of the Congo.
While most are dormant, Nyamuragira and Nyiragongo are Africa's two most active volcanoes.
Nyamuragira, to the far east, erupts every few years producing large lava flows - one of which is evident as an elongated red spot. About 10 km to the southeast, Nyiragongo has a large lava lake.
The area pictured is part of the Albertine Rift, one of Africa's most biologically diverse regions. The combination of high human population density, poverty and conflict poses a challenge to conservation. Across the mountain range, however, a series of national parks has been established to protect the fauna and flora.
In particular, these parklands protect the majestic mountain gorilla, endangered by habitat loss, disease, poaching and war. This is where the famous American zoologist, Dian Fossey, carried out her studies of gorilla groups and their behaviour.
Surrounding the parklands are thousands of colourful dots that indicated changes in the land's surface between the three radar scans that make up this composite image. These changes are primarily in vegetation as the land surrounding the mountains is blanketed with agricultural plots. There is even a clear-cut line where agricultural activities end and the protected land begins.
This contrast is also evident along the DR Congo-Rwanda border, where the political boundary can actually be seen running between two volcanoes before turning southwards.
The cluster of white radar reflections along Lake Kivu in the lower-left corner is from the city of Goma in the DR Congo.
This image was created by combining three Envisat radar acquisitions from 27 March 2003, 5 January 2006 and 12 August 2010 over the same area.
View the full resolution image.
Credit: European Space Agency (ESA)