An asteroid headed for Earth's general neighborhood will be closer than the moon Wednesday when it passes -- an estimated 217,000 miles away.
The space rock, called 2014 DX110, is estimated at about 45 to 130 feet wide -- less than the width of a football field, but at least as big as the asteroid that injured hundreds of people when it broke apart above Russia last year. DX110 will be about ninth-tenths of the distance between the moon and Earth and might be visible .
Relatively close approaches like this occur frequently, but DX110 is closer than most asteroids. A much larger asteroid, 2014 CU13, is expected to pass Tuesday within eight lunar distances -- the distance from Earth to the moon, which ranges by tens of thousands of miles over the course of the moon's orbit but averages about 238,900 miles.