Lake Ilopango, El Salvador Astronaut photograph ISS021-E-23475
was acquired on November 11, 2009, with a Nikon D2Xs digital
camera fitted with a 400 mm lens, and is provided by the ISS
Crew Earth Observations experiment and Image Science & Analysis
Laboratory, Johnson Space Center. The image was taken by the
Expedition 21 crew. The image in this article has been cropped
and enhanced to improve contrast. Lens artifacts have been
removed. The International Space Station Program supports the
laboratory to help astronauts take pictures of Earth that will
be of the greatest value to scientists and the public, and to
make those images freely available on the Internet. Additional
images taken by astronauts and cosmonauts can be viewed at the
NASA/JSC Gateway to Astronaut Photography of Earth. Caption by
William L. Stefanov, NASA-JSC. The Central American country of
El Salvador occupies a land area nearly the same size as the
U.S. State of Massachusetts, and it includes numerous
historically active volcanoes. This de