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SPACE SHUTTLE EARTH OBSERVATIONS PHOTOGRAPHY
BACKGROUND
Astronauts have used hand-held cameras to photograph the Earth for
nearly 25 years, beginning with the Mercury missions in the early
1960s. Since 1981, Space Shuttle astronauts have taken more than
37,000 photographs with the Hasselblad Model 500 EL/M and the Aero
Linhof Technika 45 hand-held cameras. About 85 percent of these
photographs are Earth-looking views. The rest show satellite
deployments, extravehicular activities, and astronaut activities in
the cabin.
Astronauts are trained in scientific observation of geological,
oceanographic, environmental and meteorological phenomena. They are
also instructed in the use of photographic techniques and equipment.
Training helps the astronauts make informed decisions on which areas
and phenomena to photograph. Specific areas of scientific interest are
selected before each flight by a group of scientists. The astronauts
receive intensive training and in-flight aids to help them locate
these sites.
PHOTOGRAPHIC CHARACTERISTICS
Most of the photographs are in natural color, although a limited
amount of black-and-white film has been used with polarizing filters.
Beginning in 1963, a small about of color infrared film was tested on
some missions.
Three lenses (50 mm, 100 mm, and 250 mm) on the Hasselblad cameras and
two lenses (90 mm and 250 mm) on the Aero Linhof camera offer a wide
variety of both areal coverage and spatial resolution. The Shuttle
flies at different altitudes; for example, on the first 24 missions,
the altitude range was between 204 and 555 km (110 and 300 nautical
miles), which adds to this variation. Table 1 offers a guideline to
the areal coverage provided by the photographs.
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TABLE 1 - APPROXIMATE DISTANCE ACROSS A VERTICAL
PHOTOGRAPH TAKEN FROM AN ALTITUDE OF 296 KILOMETERS
(160 NAUTICAL MILES)
----------------------------------------------------------------------
Camera Lens Distance
Kilometers Nautical Miles
Hasselblad 50 mm 325 175
100 mm 165 90
250 mm 65 35
----------------------------------------------------------------------
Aero Linhof 90 mm 310 x 395 170 x 215
250 mm 110 x 145 60 x 75
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A rule of thumb is that 100-mm lens offers spatial resolution similar
to that of Landsat multispectral scanner (approximately 80 m) and the
25-mm lens has resolution similar to that of the Landsat thematic
mapper (approximately 30 m).
For most Shuttle missions, the orbital tracks cover the tropical and
temperate regions of the Earth between 28 degrees N. and 28 degrees S.
latitude. Nine Space Transportation System (STS) missions have flown
at higher latitudes, with the orbits of STS Missions 9, 41-G, 51-B,
and 61-A extending to 57 degrees N. and 57 degrees S. latitude. Repeat
coverage of an area is obtained by acquiring photography on several
missions and/or by taking photographs from different viewing angles
during a single mission.
As a result of the Earth's rotation and the Shuttle's orbit duration
(approximately 90 minutes), an area may be photographed at different
Sun angles during a single mission.
Stereoscopic coverage is available for a number of areas.
USES OF THE PHOTOGRAPHY
The Shuttle hand-held photography fills a niche between the coverage
provided by aerial photography and that of unmanned satellite scanners
and complements these two familiar formats with additional
information. The ability of the trained astronaut to rapidly identify
and photograph important phenomena on the Earth makes the Shuttle
photographs unique. Near-real-time information exchange with the crew
facilitates the recording of current events of environmental,
geological, oceanographic, and meteorological importance.
Photographing at various Sun angles highlights different geologic
features and takes advantage of sun glint to show intricate ocean
structures and land/water interfaces. Critical environmental
monitoring sites are photographed repeatedly over time; some have
photographic records dating back to the Gemini and Skylab missions.
Earth-limb pictures taken at sunrise and sunset document the changes
in the Earth's atmospheric layering.Volcanic activity is monitored in
cooperation with the Scientific Event Alert Network of the Smithsonian
Institution. Meteorological phenomena are monitored and photographed
during Space Shuttle missions. Documentation of hurricanes,
thunderstorms, squall lines, island cloud wakes, and jet stream,
complements meteorological satellite data by offering better
resolution and stereoscopic coverage of such phenomena. The
photographs can be used in geologic mapping and in updating existing
maps.
OBTAINING INFORMATION ON SPACE SHUTTLE HAND-HELD PHOTOGRAPHY
Each frame of the hand-held Shuttle photography has a set of
descriptors to help the user understand the photographic content. This
information is available in a set of catalogs or through an automated
data base search.
o CATALOGS - Catalogs of the photography for each Space Shuttle
mission can be obtained by contacting the Earth
Resources Observations System (EROS) Data Center.
o DATA BASE - A computerized data base containing more than 15
descriptors for each frame of the Shuttle Earth-
looking photography has been compiled. A data base
query can be made through the EROS Data Center
o VIEWING CENTERS -
The photographs can be viewed on microfilm at
National Cartographic Information Centers: the
Technology Application Center, University of New
Mexico; the Lunar Planetary Institute, Houston, TX,
and the Library of Congress, Washington DC.
o VIDEO DISK - The Earth-viewing photography from the first 24 STS
missions is available on a video disk through the
Smithsonian Institution, Washington DC.
======================================================================
O R D E R I N G P H O T O G R A P H S
Prints, slides, and transparencies of STS Earth-looking photography
are distributed through three agencies. The primary source of the data
is:
EROS DATA CENTER
User Services Section
Sioux Falls, South Dakota 57198
Phone: (605) 594-6151
FTS: 784-7151
Other sources are:
TECHNOLOGY APPLICATIONS CENTER
University of New Mexico
Albuquerque, New Mexico 87131
Phone: (505) 277-3622
and
MEDIA SERVICES BRANCH
Still Photography Library
NASA/Lyndon B. Johnson Space Center
P.O. Box 58425, Mail Code AP3
Houston TX 77258-8425
Phone: (713) 483-4231
A user may contact these agencies for ordering assistance, price
lists, and oder forms. To order a picture, submit the Shuttle mission
number, the film roll number, and the frame number.
If the interest lies in a specific area, a listing of available
photographs can be obtained through the EROS Data Center. submit the
geographic name (i.e. country, island chain, ocean, or sea) and the
latitude and longitude coordinates for the area of interest.
The Space Shuttle Earth Observation Project Office recommends that a
user visit one of the viewing centers to select the photograph best
satisfying his or her requirements before ordering a photograph.
======================================================================
NASA, SPACE SHUTTLE EARTH OBSERVATIONS PHOTOGRAPHY, JSC, Houston, TX,
January 1987