Shop Windows to the Universe

Arches National Park Geology Tour provides an extensive, visually rich description of the geology of Arches, by Deborah Ragland, Ph.D. See our DVD collection.

Exploratour - Comparing the Surfaces of Earth and Mars

Craters

The table below contains information about the distribution of craters on Earth and Mars.

Earth


This image shows ocean temperatures (red=warm, blue=cold).
Click on image for full size version (55K GIF) Image courtesy of the U.S. Geological Survey

Two-thirds of the surface of the Earth is covered with water. The rest of the land surface is lightly cratered. On Earth, craters are erased from the surface by the action of wind and water erosion, as the surface gradually changes with time.

Mars


Close examination of these images shows numerous craters on the surface of Mars. Colors represent altitude of terrain (blue=low, red-white=high).
Click on image for full size version (160K GIF)
Image from Mars Global Surveyor, NASA/JPL

There are no oceans on Mars! Almost the entire surface of Mars is cratered to various degrees. The Tharsis Ridge, where the volcanoes of Mars are located, is lightly cratered. The lowlands of Mars are moderately cratered, but the highlands of Mars, in the southern hemisphere (seen in the upper image above), are heavily cratered.


Shop Windows to the Universe Science Store!

Learn about Earth and space science, and have fun while doing it! The games section of our online store includes a climate change card game and the Traveling Nitrogen game!

You might also be interested in:

Cool It! Game

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

ExploraTour - Looking at the World in a Different Light

Even though the sleeping man is no longer on the bed, you can still see where he was lying down. The heat from his body warmed up the bed sheets which are now radiating infrared light toward your eyes....more

ExploraTour - Looking at the World in a Different Light

All warm objects radiate in the infrared. The warmer the object, the higher the frequency and intensity of the radiation. Very hot objects give off other types of radiation in addition to infrared. Click...more

ExploraTour - Looking at the World in a Different Light

Your eye is a wonderful detector of visible light. Different frequencies of light produce different sensations in the eye which we interpret as colors. Our eyes detect light by using light sensitive components...more

ExploraTour - Looking at the World in a Different Light

Imagine you found a pair of special glasses that not only gave you telescopic vision but gave you the ability to see all forms of radiant energy. The universe in visible light contains all the familiar...more

ExploraTour - Looking at the World in a Different Light

This is a volcano on the island of Miyake in Japan. It has erupted, sending hot lava and ash into the air, a total of ten times. The time after one eruption until the next occurred was about twenty years...more

ExploraTour - Looking at the World in a Different Light

The awesome power of a giant black hole was revealed by looking at this galaxy in three different types of light. The picture that you see is of Centaurus A, a very peculiar galaxy. A galaxy is just a...more

ExploraTour - Looking at the World in a Different Light

This is a plant in Gary, Indiana where power is made. We use power to run things like television sets, radios, lights, and microwave ovens. The picture looks very strange because it was taken in infrared....more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF