This is an image of the Earth.
Click on image for full size
NASA

The Cooling of Earth

Planets cool off for many different reasons.

When Earth formed about 4 Billion Years ago, it became relatively large and warm. Earth also contains many warming elements such as the radioactive minerals, so it has not cooled as rapidly as some other planets.

Earth has had a long a complicated cooling history. An understanding of the Earth's history might begin with the record of geologic time.


You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

How a proto-planet sweeps up nearby material

As shown in this picture, while they were forming in the solar nebula, the nucleii of the planets-to-be (called protoplanets) drew material to themselves from the cloud of gas and dust around them. The...more

Element (Chemical Element)

An element (also called a "chemical element") is a substance made up entirely of atoms having the same atomic number; that is, all of the atoms have the same number of protons. Hydrogen, helium, oxygen,...more

Magma

If you could travel to the center of the Earth, you would find that it gets hotter and hotter as you travel deeper. The heat is naturally produced by decay of radioactive elements. Within the Earth’s...more

Volcanic Ash

Ash is made of millions of tiny fragments of rock and glass formed during a volcanic eruption. Volcanic ash particles are less than 2 mm in size and can be much smaller. Volcanic ash forms in several ways...more

Cinder Cones

Cinder cones are simple volcanoes which have a bowl-shaped crater at the summit and rarely rise more than a thousand feet above their surroundings. They usually are created of eruptions from a single vent,...more

Flowing Lava

Lava can move in broad flat lava flows, or it can move through constrictive channels or tubes. Lava flows have a large surface area so they tend to cool quickly and flow slowly. The fastest unconstricted...more

How Do Plates Move?

Earth’s center, or core, is very hot, about 9000 degrees F. This heat causes molten rock deep within the mantle layer to move. Warm material rises, cools, and eventually sinks down. As the cool material...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA