Most planes, including the U-2 Dragon Lady, operate in the stratosphere. The stratosphere is much colder and calmer than the troposphere beneath it. Introduced in 1957, the U-2 "still reigns supreme as the leader among manned intelligence, surveillance and reconnaissance systems," according to the U.S. Air Force.

Photograph courtesy U.S. Air Force

Download this file

Our media can be used in a variety of contexts—from media spotlights to encyclopedic entries to lessons. From this page, check out the different ways you can use this .

Other Pages That Use This Item

atmosphere Encyclopedic Entry

Best For
7 - 12 and up

Earth Science, Geography, Chemistry

Appropriate For

  • Educators
  • Families
  • Students

Encyclopedic entry. We live at the bottom of an invisible ocean called the atmosphere, a layer of gases surrounding our planet. Nitrogen and oxygen account for 99 percent of the gases in dry air, with argon, carbon dioxide, helium, neon, and other gases making up minute portions.