This EREP color photograph of the Uncompahgre Plateau area of Colorado was taken in June of 1973 by the Skylab Multi-spectral Photographic Camera (Skylab EREP Experiment S190A) of the Multi-spectral Photographic Facility during the Skylab-2 Mission.

This concept illustrates Skylab Earth observation studies, an Earth Resources Experiment Package (EREP). EREP was designed to explore the use of the widest possible portion of the electromagnetic spectrum for Earth resource investigations with sensors that recorded data in the visible, infrared, and microwave spectral regions. Resources subject to this study included a capability of mapping Earth resources and land uses, crop and forestry cover, health of vegetation, types of soil, water storage in snow pack, surface or near-surface mineral deposits, sea surface temperature, and the location of likely feeding areas for fish, etc. A significant feature of EREP was the ability of man to operate the sensors in a laboratory fashion.

This 1970 photograph shows Skylab's Multispectral Scanner, one of the major components of an Earth Resources Experiment Package (EREP). It was designed to evaluate the on-orbit use of multispectral scanning of Earth resources. Investigators could evaluate the usefulness of spacecraft multispectral data for crop identification, vegetation mapping, soil moisture measurements, identification of contaminated areas in large bodies of water, and surface temperature mapping. The overall purpose of the EREP was to test the use of sensors that operated in the visible, infrared, and microwave portions of the electromagnetic spectrum to monitor and study Earth resources. The Marshall Space Flight Center had program management responsibility for the development of Skylab hardware and experiments.

This EREP photograph of the Uncompahgre Plateau area of Colorado illustrates the land use classification using the hierarchical numbering system to depict land forms and vegetative patterns. The numerator is a three-digit number with decimal components identifying the vegetation analog or land use conditions. The denominator uses a three-component decimal system for landscape characterization.

This 1970 photograph shows Skylab's Infrared Spectrometer Viewfinder Tracking System, a major component of an Earth Resources Experiment Package (EREP). It was designed to evaluate Earth resources sensors for specific regions of the the visible and infrared spectra and assess the value of real time identification of ground sites. The overall purpose of the EREP was to test the use of sensors that operated in the visible, infrared, and microwave portions of the electromagnetic spectrum to monitor and study Earth resources. The Marshall Space Flight Center had program management responsibility for the development of Skylab hardware and experiments.

This EREP color infrared photograph of the Uncompahgre Plateau area of Colorado was taken in June of 1973 by the Earth Terrain Camera (Skylab EREP Experiment S190B) of the Skylab's Multi-spectral Photographic Facility during the Skylab-2 mission. Skylab stereoscopic data provided the best identification of vegetation complexes and delineation of vegetation boundaries, particularly in areas where changes in relief were related to changes in vegetation type (a common occurrence in wild-land vegetation communities).

This 1970 photograph shows Skylab's Microwave Radiometer/Scatterometer and Altimeter, one of the major components for an Earth Resources Experiment Package (EREP). It was designed to study varying ocean surface, soil erosion, sea and lake ice, snow cover, seasonal vegetational changes, flooding, rainfall and soil types. The overall purpose of the EREP was to test the use of sensors that operated in the visible, infrared, and microwave portions of the electromagnetic spectrum to monitor and study Earth resources. The Marshall Space Flight Center had program management responsibility for the development of Skylab hardware and experiments.

S73-34295 (June 1973) --- A vertical view of a portion of northern California reproduced from data taken from the Skylab Multispectral Scanner, experiment S192, in the Skylab space station in Earth orbit. This view is the most westerly one-third of Frame No. 001, Roll No. 518, S192, Skylab 2. Frame No. 001 extends from the Pacific coast at the Eureka area southeasterly 175 nautical miles to the Feather River drainage basin. Included in this view are Eureka, Trinidad, Klamath & Trinity Rivers and the Coastal Range mountains. This non-photographic image is a color composite of channels 2 (visible), 7, and 12 (infrared) from the Earth Resources Experiments Package (EREP) S192 scanner. The scanner techniques assist with spectral signature identification and mapping of ground truth targets in agriculture, forestry, geology, hydrology and oceanography. Photo credit: NASA

This Earth Resource Experiment Package (EREP) photograph of the Uncompahgre area of Colorado was electronically acquired in September of 1973 by the Multi-spectral Scarner, Skylab Experiment S192. EREP images were used to analyze the vegetation conditions and landscape characteristic of this area. Skylab's Earth sensors played the dual roles of gathering information about the planet and perfecting instruments and techniques for future satellites and manned stations. An array of six fixed cameras, another for high resolution, and the astronauts' handheld cameras photographed surface features. Other instruments, recording on magnetic tape, measured the reflectivity of plants, soils, and water. Radar measured the altitude of land and water surfaces. The sensors' objectives were to survey croplands and forests, identify soils and rock types, map natural features and urban developments, detect sediments and the spread of pollutants, study clouds and the sea, and determine the extent of snow and ice cover.

This high-resolution color infrared photograph of the Uncompahgre Plateau area of Colorado was taken by the Multi-spectral Photographic Camera (Skylab EREP Experiment S190A) of the Skylab's Multi-spectral Photographic Facility during the Skylab-3 mission.

This interior photograph of Skylab's multiple docking adapter (MDA) flight article, then undergoing outfitting at the Martin Marietta Corporation's Space Center facility in Denver, Colorado, shows the forward cone area and docking turnel (center) that attached to the Apollo Command Module. Designed and manufactured by the Marshall Space Flight Center, the MDA housed the control units for the Apollo Telescope Mount (ATM), Earth Resources Experiment Package (EREP), and Zero-Gravity Materials Processing Facility and provided a docking port for the Apollo Command Module.

Workmen at the Martin Marietta Corporation's Space Center in Denver, Colorado, position Skylab's Multiple Docking Adapter (MDA) flight article in the horizontal transportation fixture. Designed and manufactured by the Marshall Space Flight Center and outfitted by Martin Marietta, the MDA housed the control units for the Apollo Telescope Mount (ATM), Earth Resources Experiment Package (EREP), and Zero-Gravity Materials Processing Facility and provided a docking port for the Apollo Command Module.

At Marshall Space Flight Center, Skylab's Multiple Docking Adapter (MDA) flight article undergoes center-of-gravity testing. Developed and fabricated by MSFC, the MDA housed the control units for the Apollo Telescope Mount (ATM), Earth Resources Experiment Package (EREP), and the Zero-Gravity Material Processing Facility and provided a docking port for the Apollo Command Module.

S73-31845 (3 Aug. 1973) --- Astronaut Jack R. Lousma, Skylab 3 pilot, studies a map of the U.S. during a Skylab EREP pass across the United States, as seen in this photographic reproduction taken from a television transmission made by a color TV camera aboard the Skylab space station in Earth orbit. EREP is an acronym for Earth Resources Experiments Package. Photo credit: NASA

S73-32847 (10 Sept. 1973) --- Astronaut Gerald P. Carr, Skylab 4 commander, changes a dial on the control and display panel for the Earth Resources Experiments package (EREP) during a training exercise in the Multiple Docking Adapter (MDA) one-G trainer at Johnson Space Center. Photo credit: NASA

SL3-40-077 (July-September 1973) --- A vertical view of the Mediterranean coastal area of southeastern France as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. This view of the coast extends from the eastern outskirts of Marseilles easterly to Cannes, and includes the city of Toulon. The S190-A experiment is part of the Skylab Earth Resources Experiments Package. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-27-180 (July-September 1973) --- A vertical view of the Snowy Mountains area of Australian Alps in the States of Victoria and New South Wales, Australia, as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. This picture was taken with type 2443 infrared color film. The lake near the center of the picture is the Eucumbene Reservoir. This area is located immediately south-southwest of the capital city of Canberra. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-22-0214 (July-September 1973) --- A vertical view of southeastern Washington State as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. The Snake River flows into the Columbia River in the most southerly corner of the picture. The Wallula Lake is below the junction of the two rivers. The Yakima Valley is at the southwestern edge of the photograph. The Columbia Basin is in the center of the picture. The Cascade Range extends across the northwest corner of the photograph. This picture was taken with type SO-356 regular color film. The S190-A experiment is part of the Earth Resources Experiments Package. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL2-10-250 (May-June 1973) --- A vertical view of eastern Iowa and northwestern Illinois, as photographed from Skylab space station in Earth orbit. Davenport, Burlington and Muscatine, Iowa; and Rock Island and Moline, Illinois can be delineated on opposite sides of the Mississippi River. The Iowa River and tributaries of it can also be delineated. This photograph was taken with one of six lenses of the Itek-furnished Multispectral Photographic Facility Experiment S190-A mounted in the Multiple Docking Adapter (MDA) of the space station. A six-inch lens, using 70mm medium speed Ektachrome (SO-356) film, was used. Agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce and Interior; the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior's Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-27-224 (July-September 1973) --- A vertical view of the western portion of the Republic of Panama on the Isthmus of Panama as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. This picture was taken with 2443 infrared color film. The large, clear body of water on the north side of the isthmus is Golfo de los Mosquitos, an extension of the Caribbean Sea. The large, partly cloud-covered body of water on the south side of the isthmus is Golfo de Chiriqui, an extension of the Pacific Ocean. Federal agencies participating with NASA on the EREP project are the Department of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observation Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-28-059 (July-September 1973) --- A vertical view of the Lake Mead and Las Vegas, Nevada area as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. Lake Mead is water of the Colorado River impounded by Hoover Dam. Most of the land in the picture is Nevada. However, a part of the northwest corner of Arizona can be seen. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-22-0322 (July-September 1973) --- An oblique view of the Salt Lake City, Utah area as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. Approximately two-thirds of the Great Salt Lake is in view. The smaller body of water south of Salt Lake City is Utah Lake. The Wasatch Range is on the east side of the Great Salt Lake. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

S73-32854 (10 Sept. 1973) --- Astronaut William R. Pogue, Skylab 4 pilot, uses the Skylab Viewfinder Tracking System (S191 experiment) during a training exercise in the Multiple Docking Adapter (MDA) one-G trainer at Johnson Space Center. In the background is astronaut Gerald P. Carr, seated at the control panel for the Earth Resources Experiments Package (EREP). Carr is Skylab 4 crew commander, and Gibson is science pilot. Photo credit: NASA

This cutaway drawing details the major characteristics of the Skylab Multiple Docking Adapter (MDA). The MDA, built under the direction of the Marshall Space Flight Center, housed the control units for the Apollo Telescope Mount (ATM), Earth Resources Experiment Package (EREP), and Zero-Gravity Materials Processing Facility, and provided a docking port for the Apollo Command Module (CM).

SL4-92-300 (February 1974) --- A near vertical view of the Mobile Bay, Alabama area is seen in this Skylab 4 Earth Resources Experiments Package S190-B (five-inch earth terrain camera) photograph taken from the Skylab space station in Earth orbit. North of Mobile the Tombigbee and Alabama Rivers join to form the Mobile River. Detailed configuration of the individual stream channels and boundaries can be defined as the Mobile River flows into Mobile Bay, and thence into the Gulf of Mexico. The Mobile River Valley with its numerous stream channels is a distinct light shade in contrast to the dark green shade of the adjacent areas. The red coloration of Mobile Bay reflects the sediment load carried into the Bay by the rivers. Variations in red color indicate sediment load and the current paths within Mobile Bay. The waterly movement of the along shore currents at the mouth of Mobile Bay is shown by the contrasting light blue of the sediment-laden current and the blue of the Gulf predominately. Agricultural areas east and west of Mobile Bay are characterized by a rectangular pattern in green to white shades. Color variations may reflect the type and growth cycle of crops. Agricultural areas (light gray-greens) are also clearly visible in other parts of the photograph. Interstate 10 extends from near Pascagoula, Mississippi eastward through Mobile to the outskirts of Pensacola, Florida. Analysis of the EREP photographic data will be undertaken by the U.S. Corps of Engineers to determine bay dynamic processes. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior's Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota. 57198 Photo credit: NASA

S73-35079 (July-September 1973) --- A near vertical view of the Caribbean coast of Venezuela is seen in this Skylab 3 Earth Resources Experiment Package S190-B (five-inch Earth terrain camera) photograph taken from the Skylab space station in Earth orbit. The large body of water is the Golfo de Venezuela; and the major land mass is the Peninsula de Paraguana. The view is looking northward from the mouth of the Golfete de Coro and Punta Cardon to Punta Macolla. The peninsula is connected to the Venezuelan mainland by the narrow strip of land in the most easterly corner of the picture. The dry, arid climate on the peninsula is indicated by sparse vegetation and the abundance of sand dunes. The highest point is about 2,700 feet above the sea and is the conspicuous black spot. Old raised shoreline features appear as streaks parallel to the Golfete de Coro. Sand dunes and stream erosion have modified these features. Water of the Golfete de Coro is red from the high sediment content. The streaks in the water off the peninsula is apparently an effect of wind which is blowing sand and water offshore. The EREP investigator Dr. Jose Antonio Galavis, of the Ministerio de Mines e Hidrocarburos, will use this information to map geology and coastal sedimentation in the Peninsula de Paraguana. Federal agencies participating with NASA on the EREP projects are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. (Alternate number SL3-83-237) Photo credit: NASA

S73-35081 (July-September 1973) --- A view of approximately 3,600 square miles of north central Wyoming and southern Montana is seen in this Skylab 3 Earth Resources Experiments Package S190-B (five-inch Earth terrain camera) photograph taken from the Skylab space station in Earth orbit. The Big Horn River following northward crosses between the northwest trending Big Horn Mountains and the Pryor Mountains. Yellowtail Reservoir, named after a former chief of the Crow Indian tribe in the center of the picture is impounded by a dam across the small rectangular crop area along the Big Horn River (upper right) and the strip farming (yellow) practiced on the rolling hill along the Big Horn River and its tributaries (upper left corner and right edge). The low sun angle enhances the structural features of the mountains as well as the drainage patterns in the adjacent basins. Rock formation appears in this color photograph as they would to the eye from this altitude. The distinctive redbeds can be traced along the front of the Pryor Mountains and indicate the folding that occurred during mountain building. EREP investigators, Dr. Houston of the University of Wyoming and Dr. Hoppin of the University of Iowa, will analyze the photograph and use the results in geological mapping and mineral resource studies. Lowell, Wyoming (lower left corner) and Hardin, Montana (upper right corner) can be recognized. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. (Alternate number SL3-86-337) Photo credit: NASA

SL3-87-299 (July-September 1973) --- A vertical view of southeastern New York State is seen in this Skylab 3 Earth Resources Experiments Package S190-B (five-inch Earth terrain camera) infrared photograph taken from the Skylab space station in Earth orbit. An 18-inch, 450mm lens and type 2443 infrared Ektachrome film was used. This picture covers the northern part of New Jersey, a part of northwestern Pennsylvania, and the western tip of Connecticut. The body of water is Long Island Sound. The wide Hudson River flows southward across a corner of the photograph. The New York City metropolitan area occupies part of the picture. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-34-056 (July-September 1973) --- A near vertical view of an 8,000 square-mile area of the Grand Erg Oriental in east central Algeria as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment in the Multiple Docking Adapter of the Skylab space station. The Grand Erg contains vast areas of sand dunes and sand plains. This photograph illustrates the variety of surface features that are characteristic of the Sahara Desert. The dark areas are relatively sand free, and may contain rock outcrops along which travel is considerably easier. Sand dunes are abundant in this picture, and their size, shape, location and pattern are due to the underlying topography and direction of the prevailing winds. Scientists interested in study of dune fields will be able to use this photograph for detailed analysis of the dune features, especially their characteristics adjacent to the sand-free areas. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-45-020 (July-September 1973) --- A vertical view of the Virginia-Tennessee-Kentucky border area as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. This picture was taken with type 2443 infrared color film. The S190-A experiment is part of the Skylab Earth Resources Experiments Package. The long, narrow ridge is Pine Mountain; and it is crossed by U.S. 25E at Pineville near its southernmost end. Some 25 miles south of Pineville U.S. 25E passes through the famed Cumberland Gap which at 1,600 feet elevation crosses Cumberland Mountain. Kingsport, Tennessee is located east of Cumberland Gap near the center of the picture. Bristol, Tennessee-Virginia is further east. Greenville and Elizabethton, Tennessee can also be seen in this photograph. The clouds across the southeast edge of the picture are over the Blue Ridge Mountains. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, 57198. Photo credit: NASA

SL3-33-167 (July-September 1973) --- A vertical view of the Argentina-Paraguay border area of South America as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. This picture was taken with type 2443 infrared color film. The Parana River flows from east to west across the picture. This part of the Rio Parana is located between the towns of Posadas, Argentina, and Resistencia, Argentina. The major body of water in the large swamp area is Laguna Ibera. Note the several fires burning in this area. The largest land mass (Argentina) is south of the river. Paraguay is north of the river. Isla Apipe Grande is near the center of the photograph. The S190-A experiment is part of the Skylab Earth Resources Experiments Package. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-34-336 (July-September 1973) --- A vertical view of a portion of northern California near the Pacific coast as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment in the Multiple Docking Adapter of the Skylab space station. A cloud deck covers the Pacific Ocean. Most of Cape Mendocino is clear of clouds and extends into the Pacific as the westernmost part of California. The sinuous pattern of the Bel River (in center) flows northward into the ocean and is characteristic of the rivers that drain the coastal ranges. This area is immediately southeast of Eureka. During Skylab 3 extensive forest fires occurred near Briceland and the smoke rising from the fires is clearly visible next to the cloud bank. Redwood and fir forests are sources of lumber in this region; and a variety of clear cut (timbering) patterns appear as light against the dark forest. The patterns appear to be related to the topography. Analysis of this photograph will aid Dr. P.G. Langley, Earth Satellite Corporation, in developing methods for forest inventory using space photography. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-33-156 (July-September 1973) --- A near vertical view of the Florence, Italy area as photographed from Earth orbit by one of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. The view extends from the Ligurian Sea, an extension of the Mediterranean Sea, across the Apennine Mountains to the Po River Valley. Florence (Firenze) is near the center of the land mass. The mouth of the Arno River is at the center of the coastline. The city of Leghorn (Livorno) is on the coast just south of the Arno River. This picture was taken with type 2443 infrared color film. The S190-A experiment is part of the Skylab Earth Resources Experiments Package. Federal agencies participating with NASA on the EREP project are the Department of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

S73-32840 (10 Sept. 1973) --- Scientist-astronaut Edward G. Gibson, Skylab 4 science pilot, turns on a switch on the control box of the S190B camera, one of the components of the Earth Resources Experiments Package (EREP). The single lens Earth Terrain Camera takes five-inch photographs. Behind Gibson is the stowed suit of astronaut Gerald P. Carr, commander for the third manned mission. The crew's other member is astronaut William R. Pogue, pilot. The training exercise took place in the Orbital Workshop one-G trainer at Johnson Space Center. Photo credit: NASA

SL2-04-118 (June 1973) --- A color photograph of the San Francisco Bay, California area, taken from the Skylab space station in Earth orbit. (The picture should be held with the clouds and Pacific Ocean on the left.) Note the thickly populated and highly developed area around the bay. Among the cities visible are San Francisco, Oakland, Berkeley and San Jose. This view extends eastward to show a portion of the San Joaquin Valley. This photograph was taken by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment in the Multiple Docking Adapter of the space station. Type SO-356 film was used. The S190-A experiment is part of the Skylab Earth Resources Experiments Package (EREP). Photo credit: NASA

SL2-04-018 (June 1973) --- A vertical view of the Arizona-Utah border area showing the Colorado River and Grand Canyon photographed from the Skylab 1/2 space station in Earth orbit. This picture was taken by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment in the Multiple Docking Adapter of the space station. Type S0-356 film was used. The row of white clouds extend north-south over the dark colored Kaibab Plateau. The junction of the Colorado and Little Colorado rivers is in the southwest corner of the picture. The body of water is Lake Powell on the Colorado River upstream from the Grand Canyon. The lone peak at the eastern edge of the photograph south of Colorado River is the 10,416-foot Navajo Mountain. The S190-A experiment is part of the Skylab Earth Resources Experiments Package(EREP). Photo credit: NASA

SL2-03-118 (June 1973) --- An infrared photograph of the San Francisco Bay, California area, taken from the Skylab 1/2 space station in Earth orbit. THE PICTURE SHOULD BE HELD WITH THE CLOUDS AND PACIFIC OCEAN ON THE LEFT. This photograph was taken by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment in the Multiple Docking Adapter of the space station. Type 2443 film was used. Note the thickly populated and highly developed area around the bay. Among the cities visible in this photograph are San Francisco, Oakland, Berkeley and San Jose. This view extends eastward to show a portion of the San Joaquin Valley. The S190-A experiment is part of the Skylab Earth Resources Experiment Package (EREP). Photo credit: NASA

S73-34295A (June 1973) --- A vertical view of a portion of northern California reproduced from data taken from the Skylab Multispectral Scanner, experiment S192, in the Skylab space station in Earth orbit. This view is the most westerly one-third of Frame No. 001, Roll No. 518, S192, Skylab 2. Frame No. 001 extends from the Pacific coast at the Eureka area southeasterly 175 nautical miles to the Feather River drainage basin. Included in this view are Sacramento River Valley, Oroville Reservoir, Oroville and Chico. This non-photographic image is a color composite of channels 2 (visible), 7 and 12 (infrared) from the Earth Resources Experiments Package (EREP) S192 scanner. The scanner techniques assist with spectral signature identification and mapping of ground truth targets in agriculture, forestry, geology, hydrology and oceanography. Photo credit: NASA

S73-34295B (June 1973) --- A vertical view of a portion of northern California reproduced from data taken from the Skylab Multispectral Scanner, experiment S192, in the Skylab space station in Earth orbit. This view is the most westerly one-third of Frame No. 001, Roll No. 518, S192, Skylab 2. Frame No. 001 extends from the Pacific coast at the Eureka area southeasterly 175 nautical miles to the Feather River drainage basin. Included in this view are Lake Shasta, Sacramento River Valley, Redding and Red Bluff. This non-photographic image is a color composite of channels 2 (visible), 7, and 12 (infrared) from the Earth Resources Experiments Package (EREP) S192 scanner. The scanner techniques assist with spectral signature identification and mapping of ground truth targets in agriculture, forestry, geology, hydrology and oceanography. Photo credit: NASA

SL2-05-102 (June 1973) --- A black and white photograph of the San Francisco Bay California area, taken from the Skylab 1-2 space station cluster in Earth orbit. THE PICTURE SHOULD BE HELD WITH THE CLOUDS AND PACIFIC OCEAN ON THE LEFT. This photograph was taken by one of six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment in the Multiple Docking Adapter of the space station. Note the thickly populated and highly developed area around the Bay. Among the cities visible in this photograph are San Francisco, Oakland, Berkeley and San Jose. This view extends eastward to show a portion of the San Joaquin Valley. The S190-A experiment is part of the Skylab Earth Resources Experiments Package (EREP). Type SO-022 film was used. This station covered the spectral region from 0.6 to .07 micrometers. Photo credit: NASA

SL2-06-102 (June 1973) --- A black and white photograph of the San Francisco Bay California area, taken from the Skylab 1-2 space station cluster in Earth orbit. THE PICTURE SHOULD BE HELD WITH THE CLOUDS AND PACIFIC OCEAN ON THE LEFT. This photograph was taken by one of six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment in the Multiple Docking Adapter of the space station. Note the thickly populated and highly developed area around the Bay. Among the cities visible in this photograph are San Francisco, Oakland, Berkeley and San Jose. This view extends eastward to show a portion of the San Joaquin Valley. The S190-A experiment is part of the Skylab Earth Resources Experiments Package (EREP). Type SO-022 film was used. This station covered the spectral region from 0.5 to 0.6 micrometers. Photo credit: NASA

SL3-88-053 (July-September 1973) --- A near vertical view of the Tennessee-Virginia-Kentucky border area is seen in this Skylab 3 Earth Resources Experiments Package S190-B (five-inch Earth terrain camera) photograph taken from the Skylab space station in Earth orbit. The clock is in the most southerly corner of the picture. Interstate 81 under construction extends northeast-southwest across the bottom portion of the photograph. The larger urban area nearest the center of the picture is Kingsport, Tennessee. On the southern side of I-80 and east of Kingsport is the city of Bristol, Tennessee-Virginia. Johnson City, Tennessee is the urban area near the edge of the picture southeast of Kingsport. The Holston River, a tributary of the Tennessee River, meanders through the Kingsport area. The characteristic ridge and valley features in the Cumberland Plateau of Kentucky, Tennessee and Virginia are clearly visible. Forests (dark green) occur on the ridges and clearly outline the folded and faulted rock formations. The valleys (light) were formed in the softer rocks as a result of erosion. Agricultural areas are indicated by the characteristic rectangular patterns. Coal production is an important industry of this area; and it is mined by surface open pit operations. The irregular light areas in the Kentucky-Virginia border area are the strip mines which follow the contour of the land. Reclamation of the strip mine areas is aided through accurate knowledge of the mine and drainage systems. Dr. Ronald Brooks of the Wolf Research and Development Corporation can use this photograph in study of strip mine areas in the east central U.S. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior’s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-88-222 (18 Sept. 1973) --- The metropolitan area of Chicago is encompassed in this Skylab 3 Earth Resources Experiments Package (EREP) S190-B photograph taken on Sept. 18, 1973 from the Skylab space station cluster in Earth orbit. The surrounding major cities of Aurora and Joliet, Illinois; Hammond, Gary and East Chicago, Indiana, are easily delineated. The photograph reveals the following: (1) Cultural differentiation of commercial, industrial and residential areas for use in population and social studies in micro-macro community planning and in cultural pattern studies in the improvement of urban areas. (Aurora is one of 27 census cities of interest to Robert Alexander, a principal investigator. Alexander is with the U.S. Geological Survey). (2) The transportation network with major corridors and their interchanges, primary and feeder streets for use in network analysis and in the development of models for population movement and land use projection. (3) The agricultural lands for land use identification on crop inventory analysis; airports for use in delineation of service and infringement of major man-made features that affect ecosystem balance (support to environmental impact studies). (4) Air and water plumes for use in case studies, natural and man-made differentiation of pollution sources, in support of model development and in ecosystem research studies on the effects of pollution. (5) Recreational centers for use in relating recreational centers to population centers, establishing possible demands and in development of possible future recreational centers to support the demand. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-88-004 (July-September 1973) --- A vertical view of the Salinas River Valley area south of Monterey Bay, California area is seen in this Skylab 3 Earth Resources Experiments Package S190-B (five-inch Earth terrain camera) photograph taken from the Skylab space station in Earth orbit. The valley is an irrigated agricultural area, and is indicated by the dark-green and light-gray rectangular patterns in the centre of the picture. The city of Salinas is barely visible under the cloud cover at the top (north) end of the valley. The dark mass on the left (west) side of the valley is the Santa Lucia mountain range. The Big Sur area is on the left and partly covered by clouds. The Diablo Range forms the dark mass in the lower right (southeast) corner of the photograph. The town of Hollister is the gray area in the dark-green rectangular farm tracts which occupy the floor of the San Benito Valley in the upper right (northeast) corner of the photograph. The Salinas River flows northwestward toward Monterey Bay. The towns of Soledad, Greenfield and King City appear as gray areas along U.S. 101 in the Salinas Valley. The geology of the area is complex, and has been racked by several earthquakes resulting from movement along the San Andreas and subsidiary faults. Here, the surface expression of the San Andreas Fault can be traced from a point just west of Hollister at the contrast of dark brown and tan to a point about one inch left of the lower right (southeast) corner of the picture. Subsidiary faults are indicated by the curving trend of the rocks along the right side. The photograph will provide detailed information on land use patterns (Dr. R. Colwell, University of California, Berkeley) and fault tectonics (Dr. P. Merifield, Earth Science Res., Inc. and Dr. M. Abdel-Gawad, Rockwell International). Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior’s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-87-355 (July-September 1973) --- A vertical view of the eastern coast of Sicily area is seen in this Skylab 3 Earth Resources Experiments Package S190-B (five-inch earth terrain camera) infrared photograph taken from the Skylab space station in Earth orbit. Mount Etna, the highest volcano in Europe (10,958 feet), is still active as evidenced by the thin plume of smoke emanating from its crest. (The altitude is approximate because the height of the volcano changes with each eruption). On the flanks of Etna recent lava flows appear black in contrast to the older flows and volcanic debris that are red. Numerous small, circular cinder cones on the flanks represent sites of previous eruptions. Catania, on the Mediterranean coast south of Etna, is the largest of several cities and villages which appear as light-gray patches on the lower slopes of the volcano. Plano de Catania, south of the city of Catania, is outlined by polygonal light and dark agricultural tracts. Several lakes, the largest of which is Lake Pozzillo, show up as dark blue in the photograph. The unusual colors in the picture are due to the use of color infrared film in which vegetation appears red. This is very evident on the slopes of Etna, in the Monti Nebrodi area at upper let, and in the local areas in the lower part of the picture. Studies of Mount Etna and related volcanic features will be undertaken by Professor Roberto Cassinis of Servizio Geologio d?Italia, Rome. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observation Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

S73-35082 (July-Sept. 1973) --- A near vertical view of a portion of west Africa ravaged by drought for the past five years is seen in this Skylab 3 Earth Resources Experiments Package S190-B (five-inch Earth terrain camera) photograph taken from the Skylab space station in Earth orbit. The semi-desert scene is in southeastern Niger about 200 nautical miles east-northeast of the capital city of Niamey. A polygonal-shaped area (dark) in the lower right corner of the picture represents a range-management ranch. The dry stream beds trending diagonally across the photograph locally contain some water or vegetation (green). The beds are sources of water through shallow drilling and contain soils suitable for production of crops. The variety of tans, browns and grays are typical desert colors that represent barren rocks and soil or sand-filled ancient stream valleys. Absence of vegetation is the singular feature of the area. Dr. G. Stuckmann of the Geographic Institute, University of Technology, Mannover, Federal Republic of Germany, will use this photograph in the study of the hydrologic regime of the region through analysis of fossil drainage patterns, geological structures and accumulations of surface water. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. (Alternate number SL3-86-166) Photo credit: NASA

SL4-93-167 (February 1974) --- A vertical view of the Kennedy Space Center and the Florida Atlantic coast area is seen in this Skylab 4 Earth Resources Experiments Package S190-B (five-inch earth terrain camera) infrared photography taken from the Skylab space station in Earth orbit. This photograph shows the major land-ocean features of the Florida coast near Vero Beach northward to Cape Canaveral and the KSC complex. The launch pads for the Skylab missions are clearly visible. Identification of living vegetation is possible through the use of the color infrared film. Various shades of red portray differences in the vegetation such as shown in the patterns in the agricultural area near Vero Beach. In the Kennedy Space Center, the nearly continuous and uniform red color shows that most of the land areas are heavily vegetated. The white coastal beach areas are strongly contrasted to the red land and the blue Atlantic Ocean. Old dunal areas in KSC are visible on Merritt Island which is separated from the Launch areas by the Banana River and the mainland by the Indian River. Federal and state highways and numerous causeways over the rivers are easily identified. The Florida mainland is partly shadowed by small white clouds which cast a pronounced shadow to the east of each cloud indicated the Sun is west of solar noon. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Core of Engineers. All EREP photography is available to the public through the Department of Interior's Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

SL3-83-166 (July-September 1973) --- A vertical view of the Washington D.C. and the Baltimore, Maryland area is seen in the Skylab 3 Earth Resources Experiments Package S190-B (five-inch Earth terrain camera) photograph taken from the Skylab space station in Earth orbit. The Chesapeake Bay is on the right (east) side of the picture. The Potomac River flows through the Washington area in the lower left (southwest) corner of the photograph. Several transportation routes and major highways stand out very distinctly. Especially conspicuous are the beltways around the cities, Interstate 95 between Baltimore and the nation?s capitol and Interstate 70N leading west from Baltimore. The tunnel and harbor facilities in Baltimore show clearly, also. Identifiable features in the Washington area include the Capitol Building, the Mall area, Robert F. Kennedy Stadium (white circle), the five bridges across the Potomac, Andrews Air Force Base (on east loop), and the smaller Anacostia River. The extent of the urbanization in this area is dramatically illustrated in this picture. The photograph has sufficient resolution that the housing patterns for individual suburban areas are clearly defined with the houses shown as pink gray, wooded areas as dark green and cleared areas light green. Chesapeake Bay circulation patterns are indicated by contrast of dark and light blue. Sediment plumes (red) are seen entering the bay north and east of Baltimore. The bay bridge stands out white against the blue water. The detailed information contained in this one photograph will be of direct use to several EREP investigator teams in land use analysis, sedimentation and circulation patterns in the bay, and resource surveys of Maryland. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

S73-35080 (July-September 1973) --- A vertical view of northeast Oklahoma and the metropolitan Tulsa area is seen in this Skylab 3 Earth Resources Experiments Package S190-B (five-inch Earth terrain camera) photograph taken from the Skylab space station in Earth orbit. THE PICTURE SHOULD BE HELD WITH THE CLOCK ON THE LEFT AND THE LAKE IN THE CORNER ON THE RIGHT. THE LONG STRETCH OF HIGHWAY (U.S. 75) RUNS STRAIGHT NORTH FROM TULSA. Tulsa, a rapidly expanding city in the heart of the mid-continent oil field, has a population of approximately 330,000. The Arkansas River meanders across the southern (lower) portion of the photograph passing through Tulsa as it flows southeastward. Oologah Reservoir, the long body of water, is located northeast of Tulsa. Lake Hudson is the body of water in the right corner of the picture. Keystone Reservoir is to the west and upstream from Tulsa. Westward from Tulsa U.S. 64 makes a 45 degree bend as it turns northwest to cross the Keystone Reservoir. The thin white line over the Oologah Reservoir is a highway bridge. Bartlesville is on U.S. 75 near the north (top) corner of the picture. The Tulsa International Airport is immediately northeast of downtown Tulsa. Several smaller airfields are visible in the surrounding area. The toll roads and other major highways are clearly visible in the picture. Claremore is northeast of Tulsa on U.S. 66 with the Will Rogers Turnpike passing nearby. Sapulpa is southwest of Tulsa on the Turner Turnpike which leads toward Oklahoma City. The detailed information contained in this photograph can be extracted by direct observation and applied to updating land use and cultural maps of Tulsa and to numerous surrounding satellite cities. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. (Alternate number SL3-83-206) Photo credit: NASA

SL4-93-153 (February 1974) --- A vertical view of the Birmingham and central Alabama area is seen in this Skylab 4 Earth Resources Experiments Package S190-B (five-inch earth terrain camera) infrared photographed taken from the Skylab space station in Earth orbit. Illustrated here is the utility of color infrared film in depicting distribution of living vegetation in the 3,600 square mile Birmingham region. The Birmingham industrial complex, with a population of nearly 850,000, is the light gray area nestled in the valley between the northeast-trending ridges that are prominent topographic features in the southern Appalachian Mountains. The narrow ridges and adjacent valleys reflect folded and faulted sedimentary rocks, indicating the complex geological history of the region. Two major rivers and several reservoirs are easily distinguished in this photograph. Bankhand Lake, formed by a dam on the Black Warrior River, appears as bright blue west of Birmingham. Two lakes are formed by dams on the Goosa River east of Birmingham. Federal and state highways appear as thin white lines and are easily identified. Interstate 65 to Montgomery is the prominent white line extending southward from Birmingham. Power line clearings are visible in the center of the picture along the Goosa River, and can be traced northwestward to northern parts of Birmingham. The predominant deep red color of the picture is due to the reflections from living vegetation. In contrast are the light tan areas that commonly occur as rectangular patterns in the east part of the photograph and represent mature agricultural crops or grazing lands. Analysis of the photographic data from the earth terrain camera will be conducted by Dr. H. Jayroe of the Marshall Space Flight Center in developing analytical techniques. All EREP photography is available to the public through the Department of Interior's Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA