Imagery of the Earth is one of the most tangible products from the International Space Station and is among the most easily recognized. The Gateway to Astronaut Photography is one of NASA’s most popular websites, hosting more than 832,000 images taken onboard the ISS and tallying nearly 28 million web hits in the month of March 2012.
The US Laboratory Module, Destiny, hosts an observation window of nearly perfect optical quality that is typically oriented for direct views of the planet below and often used for precision instruments and automatic cameras controlled from the ground. Since the installation of the Cupola on Node 3, the crew onboard has wider viewing angles than ever before. Hovering in the Cupola is the closest thing to floating out in free space without a suit.
The ISS Agricultural Camera (ISSAC) was developed by the University of North Dakota to sit in the US Lab window and take multi-spectral images of the ground to help farmers and ranchers in the United States collect better data about their land. ISSAC has also assisted with disaster relief by taking imagery of the aftermath from the Japanese earthquake and tsunami, volcanic eruptions in Europe and South America, and flooding in the heartland of the US.
ISSAC operated for over 1000 hours in 2011 and the UND team is currently on-task to support the Northern Plains 2012 growing season (April-October) with on-demand remote sensing for agriculture, conservation, and land management. Farmers will be able to monitor their crop canopies with better accuracy and, thus, reduce their use of pesticides and fertilizer. Ranchers can better monitor the condition of their rangelands to prevent overgrazing and erosion.
The Crew Earth Observations program (CEO) trains astronauts in scientific observation and photographic techniques and selects target sites for the crew to observe. Fixed targets include urban areas, glaciers, river systems, impact craters, coral reefs, and analogues to geological features on Mars, such as megafans.
Megafans are created from the solid material deposited when fast-flowing water exits rough, higher terrain and flattens out on a wider plain below. By comparing what we know of the processes that generated these formations here on Earth to similar structures on Mars, we can better understand the changes we see that have taken place on the Martian surface over millennia. The astronauts also have the opportunity to record dynamic events, such as hurricanes and typhoons, dust storms, volcanoes, and fires. Having a human directly in the loop allows imagery to be taken at a variety of angles in a single pass and catch items of interest that an automated sensor might not detect. This isn’t just art, though.
From “The Art of Science”, written by William Stefanov of the CEO team:
While cities represent people’s most visible alteration of Earth’s surface, numerous other regions of the planet are also directly or indirectly impacted by human activities. Photography of glaciers, deserts, coastal regions, and lakes provide data for tracking changes. Astronauts document the advance and retreat of glacial ice due to climate change; location and structure of dune fields related to desertification; changes to coastlines and deltas following hurricanes or human development; and changes to lakes and rivers related to land cover and land use change.
An example here at home is the following image of Houston, TX, taken at night by the Expedition 22 crew. The lighting patterns clearly indicate major highways, developed neighborhoods, and industrial use. The Houston Ship Channel and the numerous refineries stand out from the more typical whites and dull oranges with their golden hues.
The Expedition 22 crew also assisted with overhead surveys of Concepcion, Chile, following a devastating 8.8-magnitude earthquake. Smoke plumes and a collapsed bridge are clearly visible.
The city of Dubai is noted for its grand architecture and ambitious construction projects. In the same view, the Expedition 22 crew was able to observe the artificial islands of Palm Jumeirah (the smallest of the three Palm projects) and The World and the world’s tallest inhabited structure, the Burj Khalifa.
Astronauts have also observed the starkly different algae blooms in the Great Salt Lake of Utah. A railroad causeway restricts the flow of water for the northern arm of the lake, resulting in salinity nearly twice that of the southern arm. Red algae flourish in the northern brine, while green algae dominate to the south.
With the expert photography of the crew on-orbit and automated instruments like ISSAC, the Station is able to provide quality imagery of our planet, its unique phenomena, and our effects on it. This helps policymakers and entrepreneurs alike make informed decisions about city planning, agricultural development, land use, disaster response, and the continuing impact of climate change.