Anaglyph, Landsat overlay Honolulu, Hawaii
Honolulu, on the island of Oahu, is a large and growing urban area with limited space and water resources. This anaglyph, combining a Landsat image with SRTM topography, shows how the topography controls the urban growth pattern, causes cloud formation, and directs the rainfall runoff pattern. Red/blue glasses are required to see the 3-D effect. Features of interest in this scene include Diamond Head (an extinct volcano on the right side of the image), Waikiki Beach (just left of Diamond Head), the Punchbowl National Cemetary (another extinct volcano, left of center), downtown Honolulu and Honolulu harbor (lower left of center), and offshore reef patterns. The slopes of the Koolau mountain range are seen in the upper half of the image. Clouds commonly hang above ridges and peaks of the Hawaiian Islands, and in this rendition appear draped directly on the mountains. The clouds are actually about 1000 meters (3300 feet) above sea level. High resolution topographic and image data allow ecologists and planners to assess the effects of urban development on the sensitive ecosystems in tropical regions.
This anaglyph was generated using topographic data from the Shuttle Radar Topography Mission, combined with a Landsat 7 satellite image collected coincident with the SRTM mission. The topography data are used to create two differing perspectives of a single image, one perspective for each eye. Each point in the image is shifted slightly, depending on its elevation. When viewed through special glasses, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and cover the right eye with a blue filter. The United States Geological Survey's Earth Resources Observations Systems (EROS) DataCenter, Sioux Falls, South Dakota, provided the Landsat data.
The Shuttle Radar Topography Mission (SRTM), launched on February 11, 2000, uses the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. The mission is designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, an additional C-band imaging antenna and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) and the German (DLR) and Italian (ASI) space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.
Size: 18 by 28 kilometers (11 by 17 miles)
Location: 21.3 deg. North lat., 157.9 deg. West lon.
Orientation: North toward upper left
Original Data Resolution: SRTM, 30 meters (99 feet); Landsat, 15 meters (50 feet)
Date Acquired: SRTM, February 18, 2000; Landsat February 12, 2000