Is the Moon larger than the Earth?

Is the Moon larger than the Earth? What is the difference in size? Question posed by Deborah.

The relative sizes of the Earth and Moon to scale
No, the Moon is not larger than the Earth. The diameter of the Moon is actually about 1/4 that of the Earth: it is much smaller.

The Earth measures around 12,742 km across whereas the Moon measures only about 3,476 km across. The photo to the right gives a good idea of the difference in size of the Earth and Moon:

The fact that the Earth is so much bigger than the Moon goes a fair way to explaining why the Earth has an atmosphere while the Moon does not: The Earth is larger and contains more mass (about eighty times as much), which means that the force of gravity produced by it is much greater, allowing it to hold on to its atmosphere.

Note that the image above only shows the difference in size of the two bodies; it does not show how far away from each other they are. If we were to travel far enough away from the Earth and Moon so that we could get them both into the same photograph, it would look something like the one below:

You could fit about 30 Earth-sized objects in the gap. Click for original.


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