Best topo map ever

This item appears on page 76 of the September 2009 issue.

The world’s most accurate topography map is a byproduct of the ASTER (Advanced Spaceborne Thermal Emission) project, a collaboration of NASA, Caltech’s Jet Propulsion Laboratory and Japan’s Ground Data System.

They used a satellite to make a minutely detailed record of Earth’s surface for scientific studies. The resulting topography map can be downloaded for free from NASA’s EOS Digital Archive. You need to register and follow some complex instructions, but it can be found at