A massive asteroid that could wipe out an entire city is making a close approach to earth this weekend. According to CNN, asteroid 2023 DZ2, dubbed "city killer", will harmlessly pass through the orbits of the earth and the moon.

The asteroid will fly past at a distance of 105,633 miles (170,000 kilometers) on the evening of Saturday. Scientists estimate its size to be somewhere between 40 and 90 metres in diameter.

The close encounter will provide astronomers the chance to study a space object from just over 68,000km away. At less than half the distance from here to the moon, the asteroid will be visible through binoculars and small telescopes, Associated Press reported.

“There is no chance of this ‘city killer’ striking Earth, but its close approach offers a great opportunity for observations,” the European Space Agency’s planetary defence chief, Richard Moissl, said in a statement.

"What's unusual about this object is that this is rather rare, that an object of this size passes so close to Earth. That happens about once every 10 years," Moissl added.

According to NASA, astronomers with the International Asteroid Warning Network see it as good practice for planetary defence, if and when a dangerous asteroid is discovered that could hit Earth.

Notably, the Virtual Telescope Project will provide a live webcast of the close approach.

Image courtesy: Twitter/@AsteroidWatch