NASA, Japan Release Most Complete Topographic Map of Earth

June 29, 2009

Steve Cole
Headquarters, Washington
202-358-0918


Alan Buis
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-0474


RELEASE: 09-150

NASA, JAPAN RELEASE MOST COMPLETE TOPOGRAPHIC MAP OF EARTH

WASHINGTON -- NASA and Japan released a new digital topographic map
of
Earth Monday that covers more of our planet than ever before. The map
was produced with detailed measurements from NASA's Terra spacecraft.

The new global digital elevation model of Earth was created from
nearly 1.3 million individual stereo-pair images collected by the
Japanese Advanced Spaceborne Thermal Emission and Reflection
Radiometer, or ASTER, instrument aboard Terra. NASA and Japan's
Ministry of Economy, Trade and Industry, known as METI, developed the
data set. It is available online to users everywhere at no cost.

"This is the most complete, consistent global digital elevation data
yet made available to the world," said Woody Turner, ASTER program
scientist at NASA Headquarters in Washington. "This unique global set
of data will serve users and researchers from a wide array of
disciplines that need elevation and terrain information."

According to Mike Abrams, ASTER science team leader at NASA's Jet
Propulsion Laboratory in Pasadena, Calif., the new topographic
information will be of value throughout the Earth sciences and has
many practical applications. "ASTER's accurate topographic data will
be used for engineering, energy exploration, conserving natural
resources, environmental management, public works design,
firefighting, recreation, geology and city planning, to name just a
few areas," Abrams said.

Previously, the most complete topographic set of data publicly
available was from NASA's Shuttle Radar Topography Mission. That
mission mapped 80 percent of Earth's landmass, between 60 degrees
north latitude and 57 degrees south. The new ASTER data expands
coverage to 99 percent, from 83 degrees north latitude and 83 degrees
south. Each elevation measurement point in the new data is 98 feet
apart.

The ASTER data fill in many of the voids in the shuttle mission's
data, such as in very steep terrains and in some deserts," said
Michael Kobrick, Shuttle Radar Topography Mission project scientist
at the Jet Propulsion Laboratory. "NASA is working to combine the
ASTER data with that of the Shuttle Radar Topography Mission and
other sources to produce an even better global topographic map."

NASA and METI are jointly contributing the ASTER topographic data to
the Group on Earth Observations, an international partnership
headquartered at the World Meteorological Organization in Geneva,
Switzerland, for use in its Global Earth Observation System of
Systems. This "system of systems" is a collaborative, international
effort to share and integrate Earth observation data from many
different instruments and systems to help monitor and forecast global
environmental changes.

NASA, METI and the U.S. Geological Survey validated the data, with
support from the U.S. National Geospatial-Intelligence Agency and
other collaborators. The data will be distributed by NASA's Land
Processes Distributed Active Archive Center at the U.S. Geological
Survey's Earth Resources Observation and Science Data Center in Sioux
Falls, S.D., and by METI's Earth Remote Sensing Data Analysis Center
in Tokyo.

ASTER is one of five Earth-observing instruments launched on Terra in
December 1999. ASTER acquires images from the visible to the thermal
infrared wavelength region, with spatial resolutions ranging from
about 50 to 300 feet. A joint science team from the U.S. and Japan
validates and calibrates the instrument and data products. The U.S.
science team is located at NASA's Jet Propulsion Laboratory.

For visualizations of the new ASTER topographic data, visit:

http://www.nasa.gov/topics/earth/features/20090629.html

Data users can download the ASTER global digital elevation model at:

https://wist.echo.nasa.gov/~wist/api/imswelcome

and

http://www.gdem.aster.ersdac.or.jp

For more information about NASA and agency programs, visit:

http://www.nasa.gov

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