A waning crescent moon is featured in this image photographed by an Expedition 24 crew member on the International Space Station.
The moon, or any object, can be measured by diameter or mass. The moon is 3,476 kilometers in diameter. This is small compared to the Earth, which has a diameter of 12,756 kilometers.
The moon’s mass is about 7.35 X 10 to the 22 power (735 with 20 zeroes after it) kilograms while the Earth weighs 5.97 X 10 to the 24 power (597 with 22 zeroes after it) kilograms.
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