A huge Boxing Day asteroid larger than the Empire State building is expected to skim Earth at 27,000mph.
The space rock, estimated to measure up to 2,034ft is potentially bigger than both the Eiffel Tower (1,063 ft) and the Empire State Building (1,453 ft).
Named 2000 CH59 after it was first discovered in 2000 - the closest the asteroid could pass earth is 4,530,666 miles.
In astronomical terms, its passing is very close – just one-twentieth of the distance between Earth and the Sun.
According to Nasa, the space rock will pass Earth at 7.54am without incident.
Nasa categorises these asteroids as "near-Earth objects" making a "close approach", but that doesn't mean they're going to hit us.
While most asteroids pass Earth peacefully as they move through the system, some get sucked into the planets gravitational pull and can be visible.
Asteroids sometimes pass the earth multiple times a day unnoticed.
On November 1, another asteroid, called 'All Saints' passed Earth completely harmlessly.
However, Nasa technology tracks the movements of the rocks as they travel through the solar system.
Nasa officially classes asteroids as a small rocky body that orbit the Sun.
Most are found in the asteroid belt between Mars and Jupiter but they can be found anywhere.
When two asteroids hit each other, the small chunks that break off are called meteoroids - which become meteors when they enter the earth's atmosphere and vapourise.
A comet is classed as an asteroid that orbits the sun however it is made of largely ice and gas which vapourise and leave stunning tails in its wake.
