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Chicxulib Crater Yucatan Peninsula, Mexico
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This is a radar image of the southwest portion of the
buried Chicxulub impact crater in the Yucatan Peninsula,
Mexico. The radar image was acquired on orbit 81 of space
shuttle Endeavour on April 14, 1994 by the Spaceborne
Imaging Radar C/X-Band Synthetic Aperture Radar (SIR-C/X-
SAR). The image is centered at 20 degrees north latitude
and 90 degrees west longitude. Scientists believe the
crater was formed by an asteroid or comet which slammed into
the Earth more than 65 million years ago. It is this
impact crater that has been linked to a major biological
catastrophe where more than 50 percent of the Earth's
species, including the dinosaurs, became extinct.
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Chicxulib Crater Yucatan Peninsula, Mexico
SIR-C Radar Image April 14, 1994
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The 180-
to 300-kilometer-diameter (110- to 180-mile) crater is
buried by 300 to 1,000 meters (1,000 to 3,000 feet) of
limestone. The exact size of the crater is currently being
debated by scientists. This is a total power radar image
with L-band in red, C-band in green, and the difference
between C- and L-band in blue. The 10-kilometer-wide (6-
mile) band of yellow and pink with blue patches along the
top left (northwestern side) of the image is a mangrove
swamp. The blue patches are islands of tropical forests
created by freshwater springs that emerge through fractures
in the limestone bedrock and are most abundant in the
vicinity of the buried crater rim. The fracture patterns
and wetland hydrology in this region are controlled by the
structure of the buried crater. Scientists are using the
SIR-C/X-SAR imagery to study wetland ecology and help
determine the exact size of the impact crater.
Spaceborne Imaging Radar-C and X-band 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. Research on the
biological effects of the Chicxulub impact is supported by
the NASA Exobiology Program.
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