More than a billion years ago, a day on Earth lasted just 18 hours, a new study reports. The distance from our planet to the moon, scientists say, is one major reason for the extra six hours we have today.
Office of Strategic Communication
More than a billion years ago, a day on Earth lasted just 18 hours, a new study reports. The distance from our planet to the moon, scientists say, is one major reason for the extra six hours we have today.