LOS ANGELES — NASA has begun releasing the most accurate global map ever created – 3-D images of mountains, valleys and plains that were put together from a trillion measurements of the Earth’s surface collected by a space shuttle crew last year.
The digital topographical maps were crunched from the 8 terabytes of data gathered during the 11-day Shuttle Radar Topography Mission, which ended in February 2000. The data – equal to 160 million pages of text – includes precise measurements of 80 percent of the Earth’s land mass.
“The map is going to be 100 times better than any other global map that we have,” said Tom Farr, the mission’s deputy project scientist at the NASA’s Jet Propulsion Laboratory in Pasadena.
Astronauts collected the data with two large radar antennas, one tucked in the shuttle cargo bay and one on the end of a 197-foot mast. The two simultaneously imaged the surface of the Earth. When combined and processed, the data gathered reveal a stereo view of the topography.
NASA expects maps created from the data – available over the Web – will help pilots dodge remote mountain peaks, scientists study drainage patterns in valleys where they’ve never set foot and the Defense Department – the mission’s main customer – better guide missiles.
More than 160 military and intelligence systems will use the digital terrain elevation data, said Thomas Hennig, the project’s manager at the National Imagery and Mapping Agency, which underwrote much of the $142 million mission.
Other uses include settling border disputes, like those that arose while hammering out the 1995 Dayton peace accord that ended the war in Bosnia.
“They can see immediately if we move it, it does this for me, and it does that for you,” Hennig said.
For now, the data will come at a trickle, with JPL releasing one mapped area each week to scientists. The first, which covers an 8,000-square-mile swath of Colorado, was released Tuesday.
“For many parts of the world that have been poorly mapped this will be a tremendous benefit to lots of people,” said Allen Carroll, chief cartographer for the National Geographic Society.
The first continental map of North America is slated for release next spring. The last of six large releases, showing the world’s islands, should come by the end of 2002. Steve Young, a researcher at NASA’s Langley Research Center in Hampton, Va., works on a project that will use the data to create a synthetic vision system pilots can use for navigation.
Such a virtual reality display would meld global positioning satellite information and topographic data to show pilots their position in three-dimensional space — including the location of obstacles.
“Hopefully, it would help to eliminate accidents due to loss of situational awareness, either in the fog or soup, with respect to where the ground, towers or mountains are,” Young said.
On the Net:
Mission site: http://www.jpl.nasa.gov/srtm