Though the Grand Canyon may receive all the attention due to its tremendous
size, the smaller canyons of the Southwest are arguably more sublime. This
true-color image of Zion Canyon in southwestern Utah was taken by the Enhanced Thematic
Mapper plus aboard the Landsat 7 satellite on October 10, 2001. Zion Canyon is located in the
lower half of the image amidst the crisscross pattern of rock formations. The canyon
walls, made of red and white sandstone, rise
2,000-3,000 feet from the canyon floor and are peppered with hanging
vegetation. Over a period of four million years, the Virgin River cut a path
through the western edge of the Colorado Plateau to form the canyon. The river
and its tributaries resemble branches across the gray-green landscape in the upper
section of the image. They eventually join the canyon, often as spectacular
slot canyons only a few feet wide, and exit at the bottom of the image on
the way to the Colorado River.
This natural-color image of Hells Canyon was captured by NASA’s Landsat-7 satellite on September 19, 2002. The image shows the northern part of the canyon, where the Imnaha River joins the Snake River.