Skip Navigation

Thermosphere and Beyond

The outer atmosphere is very thin; it contains the aurora.

Atoms Practice
Estimated3 minsto complete
Practice Thermosphere and Beyond
This indicates how strong in your memory this concept is
Estimated3 minsto complete
Practice Now
Turn In
Off the Top

Off the Top

Credit: NASA
Source: http://en.wikipedia.org/wiki/File:Top_of_Atmosphere.jpg
License: CC BY-NC 3.0

We are losing our atmosphere out to space! But don’t worry; it’s happening very slowly. How does gas escape Earth’s gravitational and magnetic fields?

Amazing But True!

  • Even gas has trouble escaping from Earth’s gravitational field.
  • Tiny amounts of hydrogen and helium escape from the top of the atmosphere.
  • One way to escape is to absorb energy from the sun.
  • Similar processes may have helped Mars to lose its atmosphere billions of years ago.

Explore More

With the links below, learn more about atmosphere loss. Then answer the following questions.

  1. Why do hydrogen and helium, but not oxygen and nitrogen, escape from the atmosphere?
  2. What does a gas molecule need to escape from Earth’s gravity?
  3. How does a gas particle escape from Earth’s magnetic field?
  4. Mars has a smaller magnetic field that Earth so it can lose gases from the atmosphere. Why?
  5. If Mars lost its hydrogen from the top of its atmosphere, why would that make it the dry rocky planet it is today?

Notes/Highlights Having trouble? Report an issue.

Color Highlighted Text Notes
Show More

Image Attributions

  1. [1]^ Credit: NASA; Source: http://en.wikipedia.org/wiki/File:Top_of_Atmosphere.jpg; License: CC BY-NC 3.0

Explore More

Sign in to explore more, including practice questions and solutions for Thermosphere and Beyond.
Please wait...
Please wait...