Orbiting over the west coast of the United States, an astronaut took this photograph using the longest lens available (1150 mm) on the International Space Station (ISS). The camera, lens, and teleconverter weigh 6.24 kilograms (13.4 pounds) on the ground, but they weigh nothing in the weightless environment aboard the ISS, allowing freer handling by the astronaut.
The image shows angular gashes in the snow-covered landscape of northeastern Wyoming. The astronaut’s eye was drawn to the open-cast pits of several coal mines that operate out of the small town of Gillette, which appears on the lower right. The coal lies at very shallow depth, making it economical to mine. The steep walls of the overlying rocks cast strong shadows in this snowy scene. Wind distributes coal dust so that the pits appear much darker, especially the largest pit in the view (upper left). For scale, the longer arm of the Gillette airport measures 1.43 kilometers (0.9 miles).
The Powder River Basin, situated between the Bighorn Mountains and the Black Hills, is a major source of low-sulfur coal, helping to make Wyoming one of the largest coal producers in the United States. The county where Gillette is situated has the highest average income in the state of Wyoming, although employment in the energy industry has started to decline slightly in the past few years.
Click here to view another coal mine in the arid landscapes of the Powder River Basin.
Astronaut photograph ISS046-E-3395 was acquired on December 28, 2015, with a Nikon D4 digital camera using an 1150 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 46 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 M. Justin Wilkinson, Texas State U., Jacobs Contract at NASA-JSC.
The United States’ highest rate of coal production is in Wyoming, with almost 4 million short tons extracted in 2004. The majority of this coal is burned to generate electrical power within the United States, but a small percentage is also goes to Spain and Canada. The Powder River Basin in the northeastern portion of the state is the most productive of Wyoming’s coal fields. The extensive coal deposits—ranging in thickness from 21 to 53 meters (70 to 175 feet)—formed over 38-66 million years ago. The source of organic material for the coal originated in swamps, estuaries, and deltas associated with the regression (retreat) of a large inland seaway that occupied central North America during the Cretaceous Period, which spanned the years between about 144 to 65 million years ago.
Since the mid- to late 1990s, the number and size of coal mines known as mountaintop removal mines increased dramatically in parts of Virginia, West Virginia, Pennsylvania, and Kentucky. The final step in processing this coal creates sludge that contains coal dust, sediment, and possibly heavy metals and chemicals. Mine operators contain the coal sludge in nearby valleys, behind huge earthen dams known as valley fills.