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Become a nitrogen atom in the nitrogen cycle in our Traveling Nitrogen Classroom Activity Kit/Game. See all our games, activity kits and classroom activities.
This is an image of the Earth's moon, along with several other moons for comparison.
Click on image for full size
NASA

A Comparison of Some Major Moons, and the Earth's Moon

This is an image of the Earth's moon, shown in the center, with several other moons for comparison.

The image shows that the Earth's moon is a lot smaller than Ganymede, Callisto, and Titan. The Earth's moon is about the same size as Io, and is a little larger than Europa.

Not shown in this picture is Triton, which is also about the same size as the Earth's moon.


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Traveling Nitrogen Classroom Activity Kit

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

Callisto

Callisto was first discovered by Galileo in 1610, making it one of the Galilean Satellites. Of the 60 moons it is the 8th closest to Jupiter, with a standoff distance of 1,070,000 km. It is the 2nd largest...more

Europa

Europa was first discovered by Galileo Galilei in 1610, making it one of the Galilean Satellites. Europa is Jupiter's 4th largest moon, 670,900 km from Jupiter. With a diameter that is about half the distance...more

Medium-sized Moons of Saturn

Saturn has // Call the moon count function defined in the document head print_moon_count('saturn'); moons. Many of those are tiny chunks of rock or ice only a few kilometers (miles) across. One of Saturn's...more

Large and Medium-sized Moons of Saturn

Saturn has // Call the moon count function defined in the document head print_moon_count('saturn'); moons. Many of those are tiny chunks of rock or ice only a few kilometers (miles) across. One of Saturn's...more

Amalthea

Amalthea was discovered by E Barnard in 1872. Of the 17 moons it is the 3rd closest to Jupiter, with a standoff distance of 181,300 km. Amalthea is about the size of a county or small state, and is just...more

Evolution of Callisto

Most of the moons and planets formed by accretion of rocky material and volatiles out of the primitive solar nebula and soon thereafter they differentiated. Measurements by the Galileo spacecraft have...more

Very Large Impact Crater

Many examples of the differing types of terrain are shown in this image. In the foreground is a huge impact crater, which extends for almost an entire hemisphere on the surface. This crater may be compared...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