Here's Looking at You.

The space shuttle maps mysteries of the Andes.

IN AN AGE WHEN SPY SATELLITES CAN read the number off your car's license plate, one would think that scientists had long ago mapped every nook and cranny of the Earth's surface. In truth, many areas of the world are as much a mystery today as when the early explorers first ventured across trackless oceans half a millennium ago.

Excluding the United States, Europe and Australia, most of the world just isn't well-mapped. Among the bigger blind spots: one of Latin America's largest and best-known features, the Andes mountain range.

Cornell University professor Bryan Isacks is part of a team of geologists that has spent the past two decades trying to unravel the mysteries of the Andes. Now they've got an extra tool--high-definition photos taken by National Aeronautics and Space Administration from aboard the U.S. Space Shuttle orbiter Endeavour.

As part of the Shuttle Radar Topography Mission, the Endeavour was outfitted with radar technology sophisticated enough to reconstruct topographical images of the Earth at a resolution of 30 meters, enough to study large land and water features but not quite enough to pick out details on buildings. Over a single, 10-day mission in February 2000, the shuttle collected data from 80% of the Earth's land surfaces.

The data, held by the U.S. government's NASA and the National Imagery and Mapping Agency (NIMA), will be used to create the most accurate and complete high-resolution database of the Earth's topography.

For the first time, geologists will be able to consider the interplay of uplift and other tectonic forces and the eroding effects of climate on a mountain range. They will be able to compare what they know about places like the Sierra Nevada to places for which there are virtually no maps, like the Himalayas.

Isacks and his team want data to better understand how mountain ranges such as the Andes were formed. Getting decent images of the range, until now, has been no picnic.

"In Bolivia and Peru, the east side of the Andes is very wet and rainy, making it extremely difficult to map with aerial photography, which continues to be the standard mapping method," says Isacks. "The Argentinian Patagonia also has very little mapping. These are areas that have cloud cover almost all the time."

Many of the questions puzzling geologists today focus on the Andes. There's controversy, for example, over how the Andes "got bent," as Isacks puts it. Why, in other words, do the Andes--which for the most part run in a vertical northsouth alignment--briefly switch to an east-west orientation at the border of Peru and Chile?

New views. Another enigma is an escarpment running along the western side of the Andes--a steep cliff where elevations rise from one to four kilometers for stretches of only 20 or 30 kilometers long. "We don't really understand what structural features produced this giant rise in topography," says Isacks.

But application of the data doesn't stop at maps, says NASA official Tom Farr, the mapping project's deputy project scientist. Non-scientific uses of the data in business will be far-reaching, as the plethora of re-sellers of limited, private satellite data over the Internet attests. "We're going to be revolutionizing the geosciences," Farr says. "I think we'll really be amazed at the applications they'll come up with for it."

One such application is airline travel safety. Airplane pilots now use satellites in conjunction, the so-called Global Positioning System (GPS), to track their location. But there's still room for error if a pilot is unfamiliar with a particular area's topography. Using the data collected by the NASA mission in conjunction with GPS will make it possible to alert pilots if they fly to close to a mountain that might be obscured by darkness or bad weather.

Business applications also loom, says Farr. Oil and mining companies will be able to analyze the data to determine the likely locations of new oil, silver or gold deposits. Cellular phone companies can use the information to determine the optimal spots for new towers, problematic in hilly countries like Colombia or Ecuador.

Flood control, soil conservation, reforestation, volcano monitoring and earthquake research will also benefit from data. Once it is released to the public, ordinary people around the globe will be able to look at streams and ponds in their home towns by checking the Web site of the U.S. Geological Survey. Backpackers, for example, planning a trip to Aconcagua, the highest peak in the Andes and a popular stop for climbers, will have instant access to the topography of the area they plan to hike.

Risk and reward. That's when--and if--all of the data is released. After nearly 18 months of waiting, Isacks and his colleagues are getting impatient. To be sure, eight terabytes of data takes a lot of time to process. But part of the delay stems from concern in the Department of Defense that making high-resolution data available to anybody and everybody is a risk.

In part, defense officials fear ultra-high-quality maps of the Earth's cities could help terrorists plan bomb attacks and aid rogue nations in fixing missile targets. Nevertheless, full resolution data for the United States will be released when it is ready, NASA says.

For now, however, most of the public will have access to only 90-meter resolution data of areas outside the United States. Scientists will be able to request 30-meter resolution data for small areas of the rest of the world for study until a decision is made by Defense. "At least for now, I think NIMA feels that it's in the U.S.' best interest to withhold that full-resolution data of the whole world," says Farr. "If NIMA needs to respond to an emergency somewhere in the world, they'll have the data on hand."

In other words, a little mystery will remain for now. But Isacks and his team can soon, they hope, get cracking on better understanding the Andes, the world and our place in it.