Cooling History, part 1



This is an image the ocean floor of the Earth, showing mountain ranges, subduction trenches, tectonic plastes, and mid-ocean ridges.
Click on image for full size version (40K GIF)
Image from: U.S. Geological Survey

A planetary body, whether the body is a planet or a moon, cools slowly by radiating energy away into space. The warmth remaining inside a body controls what sort of surface activity, atmospheric activity, and interior activity which the body has. As planetary bodies cool slowly, heat diminishes, and the activities diminish to nothing. Examination of a body for various kinds of activities tells scientists what stage a body is in it's history of cooling.

The heat of a body comes from

  • 1.) leftover heat from it's formation
  • 2.) radioactive material found in the body
  • 3.) outside forces on the body as a whole, such as those which cause tides
  • 4.) heat brought to the atmosphere by energetic particles in space
  • 5.) warming by the sun
The terrestrial planets have internal heat due to (2) above, and this source of energy drives continental drift on the surface. The giant planets have internal heat due to (1) above, and this source of energy drives the motions of the atmosphere.


Return to Earth's Surface & Interior


Cooling History



This is an image the ocean floor of the Earth, showing mountain ranges, subduction trenches, tectonic plastes, and mid-ocean ridges.
Click on image for full size version (40K GIF)
Image from: U.S. Geological Survey

A planetary body, whether the body is a planet or a moon, has to cool off. The warmth contained inside a body controls what sort of surface activity, atmospheric activity, and interior activity which the body has. As planetary bodies cool slowly, heat diminishes, and the activities diminish to nothing. Examination of a body for various kinds of activities tells scientists what stage a body is in it's history of cooling off.

The heat of a body comes from

  • 1.) leftover heat from when it formed
  • 2.) radioactive material found in the body
  • 3.) outside forces on the body as a whole, such as those which cause tides
  • 4.) heat brought to the atmosphere by energetic particles in space
  • 5.) warming by the sun
The Earth-like planets have internal heat due to (2) above, and this source of energy causes continental drift on the surface. The giant planets have internal heat due to (1) above, and this source of energy causes the motions of the atmosphere.


Return to Earth's Surface & Interior


Cooling History



This is an image the ocean floor of the Earth, showing mountain ranges, subduction trenches, tectonic plastes, and mid-ocean ridges.
Click on image for full size version (40K GIF)
Image from: U.S. Geological Survey

A Planet or a moon cools off slowly in time, just like the sidewalk cools off in the evening after a sunny day. The warmth contained inside a planet or moon controls what sort of activity the planet or moon has in the atmosphere or surface. As planetary bodies cool slowly, heat diminishes, and the activities diminish to nothing. Examination of a planet or moon for various kinds of activities tells scientists what stage a body is in it's history of cooling off.

Planets or moons get energy from

Energy from item (2) in this list causes the continents to drift slowly around the surface of the Earth.


Return to Earth's Surface & Interior



Last modified January 15, 1997 by the Windows Team

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