The asteroid, dubbed Asteroid 2018 FK5, will come flying by on an Earth Close Approach trajectory. The asteroid will arrive close to Earth later tonight (Tuesday, October 1). US space agency NASA expects Asteroid FK5 to make an appearance around 11.56pm BST (10.56pm UTC). When this happens, the rock will shoot by at speeds of around 10.48km per second or 23,443mph (37,728kph).

The speedy asteroid was first observed flying around the solar system on March 28, 2018.

NASA has since calculated the objects size, speed and trajectory based on a total of 33 observations.

The asteroid was determined to be a so-called Near-Earth Object or NEO.

All NEOs are comets and asteroids in the inner solar system that approach Earth from a close distance.

READ MORE: How often do asteroids hit Earth? What is the danger?

Frequently, NEOs of varying sizes cross Earths orbit and sometimes they strike the planet head-on.

NASA said: As they orbit the Sun, Near-Earth Objects can occasionally approach close to Earth.

Note that a close passage astronomically can be very far away in human terms: millions or even tens of millions of kilometres.

Asteroid FK5 is estimated to measure somewhere in the range of 19ft to 42ft (5.8 m to 13m) across.

READ MORE: Watch major asteroid DESTROY Earth in fiery crash simulation

At the upper end of this scale, the asteroid is about as tall as Brachiosaurus dinosaur.

At the lower end of NASAs estimate, the space rock is comparable in size to an adult giraffe.

If an object this small entered the atmosphere, it would safely burn up before striking the ground.

NASA said any object up to 82ft (25m) in diameter is unlikely to survive the fiery descent through the atmosphere.

READ MORE:NASA unveils $600m planetary defence system

Despite its incredibly fast approach today, the asteroid will not come close enough to strike.

At its closest, NASA predicts the asteroid will miss our home planet from a distance of about 0.03405 astronomical units (au).

A single astronomical unit is the distance from Earth to the Sun about 93 million miles (149.6 million km).

In other words, the asteroid will safely fly by from a distance of about 3.16 million miles (5.09 million km).

1. A football field-sized space rock slams into the planet roughly once every 2,000 years, according to NASA.

2. Some of the bigger objects in the asteroid belt measure around 583 miles across.

3. NASA estimates a car-sized asteroid collides with Earth about once a year.

4. Comets are different from asteroids because they are covered in icy layers that sublimate in space.

5. If a meteor survives the descent through the atmosphere it is called a meteorite.

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Asteroid alert: NASA tracked rock about to skim Earth at 23,400mph tonight - Will it hit? - Express.co.uk