Halloween asteroid to shave past Earth, astronomers say

An image of the far side of the moon as it crosses between a Nasa probe and the Earth, a million miles away.
An image of the far side of the moon as it crosses between a Nasa probe and the Earth, a million miles away.AFP

MIAMI (AFP) - A big asteroid is hurtling towards Earth and will shave past our planet on Halloween, but astronomers say there's no need to be spooked - it's definitely not on a collision course.

The space rock is about the size of a football stadium and is moving at an "unusually high" speed of 126,000 kmh, said Nasa.

Early estimates put the asteroid - called 2015 TB145 - at about 470m in diameter, according to the astronomy website Earth and Sky.

Nasa expects it to be the largest known cosmic body to get near our planet until 2027.

"If the size is correct, the new found asteroid is 28 times bigger than the Chelyabinsk meteor that penetrated the atmosphere over Russia in February 2013," Earth and Sky said.

The good news is this asteroid will pass at a very safe distance of nearly 500,000km, or 1.3 times the span between the Earth and the Moon.

The asteroid will actually pass closer to the Moon than the Earth, skimming by at a distance of nearly 290,000km.

Astronomers may be able to spot it with telescopes, though amateur skywatchers will likely not be able to see it with the naked eye.

The time of the closest pass is 11.14am US Eastern time (1514 GMT) on Oct 31.