The asteroid space scientists feared would hit Earth may now smash into the Moon instead.

Space rock 2024 YR4 was originally calculated to have 3.1% probability of impacting our planet on 22 December 2032.

However, thanks to new observations by NASA's powerful James Webb Space Telescope (JWST), researchers believe there is a chance of impact on the lunar surface.

An international team of astronomers wrote in a research memo: "While an Earth impact by 2024 YR4 on December 22, 2032, has now been ruled out, it continues to have a non-zero probability of impacting the Moon at this time."

They add that additional observations of 2024 YR4 will be made by JWST in May 2025, which will "primarily help refine the orbital and thermal properties" of the asteroid."

A chilling visualisation had shown what might happen if the asteroid hit Earth in 2032, as scientists feared.

If the asteroid were to strike Earth, the energy released could be equivalent to 8 megatons of TNT, capable of devastating an area the size of Washington, D.C.

An 8-megaton explosion would be over 500 times more powerful than the atomic bomb dropped on Hiroshima, which had a yield of approximately 15 kilotons (0.015 megatons).

Online reactions before Earth impact was discounted had included: "I guarantee they are already building bunkers underground" and "That won't happen because obviously Bruce Willis and Ben Affleck are going to go up there, drill a hole in the side and nuke it."