February 26, 2022
The moon is moving farther away from Earth, at a rate of about 1 in (2.54 cm) every year. The gravitational force the moon exerts on the Earth is pulling energy from the Earth’s motion, which slowly pushes the moon further from us. This transfer of energy is also causing both the moon to take longer to orbit Earth, and the Earth to take longer to rotate on its axis. All these changes are incredibly small and unnoticeable in our lifetimes; however, they will add up over billions of years.
This image shows the far side of the moon as it passes between Earth and the DISCOVR spacecraft. For a visualization of the moon moving farther from Earth over time, watch this YouTube video created by NASA scientist Dr. James O’Donoghue. https://www.youtube.com/watch?v=hi8xWqHBk84. Image credit: NASA/DISCOVR
