'Surprise' bus-sized asteroid skims past Earth at 21,000mph

A "surprise" asteroid which NASA only spotted on Christmas Day has skimmed past the Earth.

The asteroid, named 2017 YZ4, came its nearest to Earth at 3:56pm GMT on Thursday, missing us by a mere 140,000 miles (224,000km).

In comparison the moon is 238,000 miles (384,000km) away.

It was travelling at approximately 21,000mph (34,000kph) - 16 times faster than a rifle bullet, covering the distance between London and New York in roughly 10 minutes.

It is the 52nd asteroid to skim past the Earth by a distance less than that of the Moon this year.

Lindley Johnson, Planetary Defense Officer at NASA's Science Mission Directorate in Washington DC told Newsweek that there are thousands of similar objects in space.

"As of December 25, there are 17,506 known Near-Earth Objects (NEOs), in orbits around the Sun that could come close to our planet; 17,400 are asteroids and 106 are comets."

Asteroids and comets are differentiated based on what they are mad of. Asteroids are composed of metals and rocks, while comets are mostly made up of ice and dust.