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-43922
                                                   April 16, 1994
                                              Raco vegetation map

This is a vegetation map of the Raco, Michigan area produced from
data acquired by the Spaceborne Imaging Radar C/X-Band Synthetic 
Aperture Radar (SIR-C/X-SAR) onboard space shuttle Endeavour. 
The radar image, taken on April 9, 1994,  has been used by
science team members at the University of Michigan to produce
detailed map of land cover.    The imaged area is approximately
24 by 32 kilometers (15 by 20 miles).  The Raco airport, which is
a decommissioned military base, is easily identified by its
triangular runway structure.  An edge of Lake Superior,
approximately 44 kilometers (27 miles) west of Sault Sainte
Marie, appears in the top right of the image..  In this land
cover map each 30- by 30-meter (98- by 98-foot) spot is
identified as either a water surface, bare ground, short
vegetation, deciduous forest, lowland conifers or upland
conifers.  Different types of ground cover have different effects
on Earth's chemical, water and energy cycles.  By cataloguing
ground cover in an area, scientists expect to better understand
the processes of these cycles in a specific area.

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Spaceborne Imaging Radar-C and X-Synthetic Aperture Radar 
(SIR-C/X-SAR) is part of NASA's Mission to Planet Earth. 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), with the
Deutsche Forschungsanstalt fuer Luft und Raumfahrt e.v. (DLR),
the major partner in science, operations and data processing of
X-SAR.

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