An astronaut aboard the International Space Station centered this photograph on the largest group of lights in the northeastern United States. New York City and Newark, New Jersey, lie at the center of a string of city lights stretching roughly 300 kilometers (200 miles) from Philadelphia to Hartford. The characteristic shape of Long Island, during night and daylight overpasses, is one of the most recognizable features to an astronaut looking at the Northeast coast.
Night-light intensity indicates population densities, a phenomenon well-known to urban geographers. An important pattern is the progressive decline of population density away from the cores of the largest cities. Lower population densities appear in the southern counties of New Jersey, though the barrier islands are defined by narrow shoreline developments. Some rural areas in the photo have fewer lights than shipping lanes of the North Atlantic Ocean.
A network of thin lines indicates highways and main roads—which can be difficult to discern in daylight images—radiating from the major cities. One of the brightest lines is Interstate 95, which crosses the entire image from a point west of Philadelphia through New York—where it is overwhelmed by city lights—and along the coast of Connecticut.
Astronaut photograph ISS050-E-29655 was acquired on January 10, 2017, with a Nikon D4 digital camera using a 45 millimeter lens, and is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. The image was taken by a member of the Expedition 50 crew. The image 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 Andi Hollier, Hx5, JETS Contract at NASA-JSC.