× This page contains archived content and is no longer being updated. At the time of publication, it represented the best available science.

Baltimore is located along the mid-Atlantic coastline of the United States, at the terminus of the Patapsco River into Chesapeake Bay. It is the largest seaport along this part of the coast, and the subject of this astronaut photograph from the International Space Station. Like many large U.S. metropolitan areas, the most brightly lit areas correspond to the highest density of buildings and typically indicates the urban core—including, in this case, the “Inner Harbor” tourist and commercial area.

Highways and large arterial streets appear as bright yellow-orange lines extending outwards into the surrounding suburbs (light violet and reddish brown regions of diffuse lighting). Dark areas beyond the suburban zone are rural or, to the southeast, indicate the waters of Chesapeake Bay. Small, dark patches are open spaces, including parks, cemeteries, and the Baltimore Zoo (within Druid Hill Park). Two large, brightly-lit areas along Chesapeake Bay are commercial/industrial regions and include the major port facilities for Baltimore.

The City of Baltimore was incorporated in 1796, after serving as the de facto capital of the nascent United States of America during the Second Continental Congress (December 20, 1776, to March 4, 1777). Today, the Baltimore metropolitan area (as defined by the Baltimore Metropolitan Council) includes more than 2.5 million people and parts of five Maryland counties—Anne Arundel, Baltimore, Carroll, Harford, and Howard. The region is also a focus of urban ecological research through the Baltimore Ecosystem Study that is part of the National Science Foundation’s Long Term Ecological Research network.

Astronaut photograph ISS033-E-14186 was acquired on October 16, 2012, with a Nikon D3S digital camera using a 400 millimeter 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 33 crew. It has been cropped and enhanced to improve contrast, and lens artifacts have been removed. The International Space Station Program supports the laboratory as part of the ISS National Lab 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, Jacobs/ESCG at NASA-JSC.