Abuja, Nigeria, 2021
Abuja, the capital of Nigeria, is one of the fastest growing cities in Africa. It was developed as a planned city, replacing Lagos, the country's most populous city, as the capital in 1991. By 2000, the population was about 800,000; by 2020, the city, and its adjoining urban area of Karu to the east, had grown to over 6 million. The images were acquired December 2, 2003 and March 5, 2021. They are located at 9.1 degrees north, 7.5 degrees east, and cover an area of 25.5 by 37.5 km.
With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of about 50 to 300 feet (15 to 90 meters), ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched Dec. 18, 1999, on Terra. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and data products.
The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping and monitoring of dynamic conditions and temporal change. Example applications are monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.
The U.S. science team is located at NASA's Jet Propulsion Laboratory in Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate, Washington.
More information about ASTER is available at http://asterweb.jpl.nasa.gov/.