Space-based technology is changing the way in which Earth is mapped. Instruments and cameras flown on spacecraft or satellites can gather data and images of areas that have been difficult to map in the past. For example, remote areas of Earth, like rugged mountain chains and rocky deserts, are difficult to map from the ground.

In February 2000, Space Shuttle Endeavor completed a mission in which radar was used to map Earth's topography from space. The mission was called the Shuttle Radar Topography Mission (SRTM). The shuttle orbited Earth for ten days, and the mission mapped over 80% of Earth's surface.

The SRTM data are being processed for building a digital topographic database of Earth. SRTM elevation data can be combined with Landsat images to produce breathtaking views of Earth.

  !   Explore these links to find out more about SRTM.

SRTM at NASA
SRTM Mission
Why Use Radar?
Santa Barbara SRTM Image

Topographic maps provide just one method for visualizing the shape of Earth's surface. Other methods, such as raised relief images and three-dimensional renderings, also show topography.

  !   Follow these links to explore sites that show more topographic maps, images, and mapping information.

Relief Maps, Topographic Maps, and Aerial Photos for the U.S
Topographic and Aerial Map FlyOvers
Topographic Mapping
Topographic Maps