You know how people who spend too much time in the sun look older than they are? It's the same for Earth's only natural satellite: A few billion years of exposure with no atmosphere to block the sun's radiation, and suddenly passing asteroids are calling you "the old dude." I kid, of course. Asteroids aren't nearly that rude. But it does appear that scientists were slightly off in their initial estimates of the moon's age. From Phys.org:
Improved age data for the Moon suggests that it is much younger than previously believed according to scientists presenting at a Royal Society discussion meeting entitled Origins of the Moon this week. Professor Richard Carlson of the Carnegie Institution of Washington will say that Earth's Moon is more likely between 4.4 and 4.45 billion years old rather than 4.56 billion years old, as previously thought.
So the moon may be about 100 million years younger than we first believed. Granted, that's like finding out your mother is two weeks younger than you thought. But still! Besides requiring the moon to change its date of birth on its Facebook page, does this matter? Yes, according to Professor Richard Carlson of the Carnegie Institution of Washington, who explains to Phys.org: "There are several important implications of this late Moon formation that have not yet been worked out," Carlson says. "For example, if the Earth was already differentiated prior to the giant impact, would the impact have blown off the primordial atmosphere that formed from this earlier epoch of Earth history?" Beats me, professor. Let me check Wikipedia and I'll get back to you. Now read this: