Earth is pushing the moon away faster now than it has for most of the past 50 million years, mostly a result of tides, a U.S. researcher says.
Matthew Huber of Purdue University says his models of the influence of tides on the moon's orbit help solve a longstanding mystery concerning the moon's age, NewScientists.com reported Wednesday.
The moon's gravity creates a daily cycle of low and high tides that dissipates energy between it and Earth, slowing the planet's spin on its axis and causing the moon's orbit to move farther away by about an inch and a half a year.