A HUGE asteroid is flying past Earth tomorrow and will closer approach in eight years.

Asteroid 99942 Apophis will fly past Earth this Friday (March 5) giving astronomers an opportunity to study the body ahead of the asteroid's closer approach in 2029.

During its 2021 pass Apophis - which is pronounced 'uh-pow-fuhs' and measures 400 metres across - will comfortably skirt our planet at a safe distance of 10,471,577 miles.

However, in April 2029 Apophis will literally shave Earth at a distance of just 23,441 miles - it will be visible to the naked-eye as it passes among the zone where high altitude satellites are present.

As with a number of other asteroids, Apophis has been classified as a potentially hazardous asteroid (PHA) by the International Astronomical Union’s Minor Planet Center.

This means that Apophis (named after an evil snake god who - according to Egyptian mythology - devours the sun every night) is an asteroid whose orbit brings it occasionally near to Earth, and is large enough to cause “significant regional damage” in the event of an impact.

Discovered on June 19 (2004) by American astronomers Roy A. Tucker and David J. Tholen, along with Italian astronomer Fabrizio Bernardi, the asteroid is comfortably larger than the Eiffel Tower and its April 2029 passage will be the closest asteroid of its size in recorded history to pass Earth.

With further passes to follow the asteroid's April 12 (2068) odds of striking the Earth are one in 380,000.

While Apophis is not an imminent threat to Earth scientists are running a simulated planetary defence scenario pretending that they just spotted it in the sky in December, to prepare for a possible situation in the future.