home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
PC Media 4
/
PC MEDIA CD04.iso
/
nasa
/
sc-oetzt.txt
< prev
next >
Wrap
Text File
|
1995-02-23
|
3KB
|
62 lines
PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIFORNIA 91109. TELEPHONE (818) 354-5011
PHOTO CAPTION P-43890
April 13, 1994
Oetztal, Austria
This image is a false-color composite of Oetztal, Austria located
in the Central Alps centered at 46.8 degrees north latitude,
10.70 degrees east longitude, at the border between Switzerland
(top), Italy (left) and Austria (right and bottom). The area
shown is 50 kilometers (30 miles) south of Innsbruck, Austria.
This image was acquired by the Spaceborne Imaging Radar-C and
X-Band Synthetic Aperture Radar (SIR-C/X-SAR) aboard the space
shuttle Endeavour on its 14th orbit. Oetztal is a SIR-C/X-SAR
hydrology supersite. Approximately one quarter of this image is
covered by glaciers, the largest of which, Gepatschferner, is
visible as a triangular yellow patch in the center of the scene.
The summits of the main peaks reach elevations between 3,500 and
3,768 meters (11,500 and 12,362 feet) above sea level. The
tongues of the glaciers are descending from elevated plateaus
down into narrow valleys which were formed during the last ice
age. This color image was produced in C-band using
multi-polarization information (red=CHV, green=CVV,
blue=CVV/CHV). The blue areas are lakes (Gepatsch dam at center
right; Lake Muta at top right) and glacier ice. The yellow areas
are slopes facing the radar and areas of dry snow. Purple
corresponds to slopes facing away from the radar. Yellow in the
valley bottom corresponds to tree covered areas. There is 30 to
50 centimeters (12 to 20 inches) of dry, fresh snow on the
glaciers, and about 10 centimeters (4 inches) in the valley at
the city of Vent, Austria (center). At these data were taken,
the weather was cold, with snow and thick fog. The entire area
would appear white to an optical sensor because it is all covered
under a winter snowpack. Researchers are interested in Oetztal
because knowing how glaciers shrink and grow over time is an
important indication of climatic change.
-----
Spaceborne Imaging Radar-C and X-Synthetic Aperture Radar
(SIR-C/X-SAR) is part of NASA's Mission to Planet Earth (MTPE).
The radars illuminate Earth with microwaves allowing detailed
observations at any time, regardless of weather or sunlight
conditions. SIR-C/X-SAR uses three microwave wavelengths:
L-band (24 cm), C-band (6 cm) and X-band (3 cm). The
multi-frequency data will be used by the international scientific
community to better understand the global environment and how it
is changing. The SIR-C/X-SAR data, complemented by aircraft and
ground studies, will give scientists clearer insights into those
environmental changes which are caused by nature and those
changes which are induced by human activity. SIR-C was developed
by NASA's Jet Propulsion Laboratory. X-SAR was developed by the
Dornier and Alenia Spazio companies for the German space agency,
Deutsche Agentur fuer Raumfahrtangelegenheiten (DARA), and the
Italian space agency, Agenzia Spaziale Italiana (ASI).
#####