GREENBELT, Md., May 30 (UPI) -- Anyone who's been to the beach -- and seen the ocean's tides -- knows the moon's gravitational effects on Earth are rather obvious. The effects of Earth's gravitational pull on the moon are less apparent.
But a new study by scientists at NASA -- published in the journal Geophysical Research Letters -- shows even the shape of the moon's all-solid surface changes in response to the position of Earth.