An asteroid is expected to whip past Earth in the closest approach ever for an object of this size on Friday afternoon.
Here's what you need to know:
What is the asteroid named?
Why is it such a big deal?
This is the largest asteroid to pass this close to Earth since humans have started watching the skies.
Is there a chance that it will smash into Earth?
How big is it?
The asteroid is 150 feet wide, or about half the size of a football field. It weighs 286,000,000 pounds (143,000 tons), or about the heft of 18,000 full-grown elephants.
How big is that compared to other asteroids?
This is considered a small to medium-sized asteroid, compared to what we know is out there.
When will the asteroid fly by Earth?
Asteroid 2012 DA14 will pass over Indonesia on Friday, Feb. 15, at 2:25 p.m. EST.
How far away will the asteroid be?
17,200 miles above Earth's surface. This is about one-tenth of the distance between the Earth and the moon, and about 5,000 miles closer than the orbit of most communication and weather satellites around Earth.
How fast is the asteroid moving?
It's moving at 17,450 mph, or about 5 miles per second.
Will I be able to see the asteroid?
Yes, if you are in the right place at the right time. It will be visible over parts of Europe, Asia and Africa, but you'll need a pair of binoculars or a telescope to see it.
But what if I'm stuck inside?
What will it look like in the sky?
It will look like a very faint dot moving pretty fast from south to north, between the constellations of Leo and the Plough.
When was it discovered?
It was discovered almost exactly one year ago, on Feb. 23, 2012, by amateur astronomers in southern Spain.
What kind of impact would 2012 DA14 have if it did slam into Earth?
Scientists think that if the asteroid were to hit land, it would produce a similar blast to one that may have hit Siberia in 1908, known as the Tunguska Event. The object caused an explosion that flattened an area the size of Tokyo. If it hit the ocean, it would cause a tsunami.
When will this asteroid make its next close approach?
Not for another 33 years. 2012 DA14 will come within 620,000 miles of Earth on Feb. 15, 2046.