A giant asteroid big enough to raze a city is expected to fly between Earth and the moon on Saturday.

The large rock, named 2023 DZ2, was only discovered in late February.

Its estimated diameter is between 40 and 100 meters, the European Space Agency (ESA) said.

Such a fly-by "happens only about once per decade," wrote NASA's Planetary Defense Coordination Office on Twitter, adding that the track of 2023 DZ2 takes it "safely" past Earth.

According to the ESA, at its closest point to our planet – expected at 1950 GMT Saturday – the asteroid will be about 168,000 kilometers away. By comparison, the moon is 384,400 kilometers from Earth.

With a clear sky, the asteroid can be observed with binoculars or a telescope.

"There is no chance of this 'city killer' striking Earth, but its close approach offers a great opportunity for observations," said the ESA's planetary defense chief, Richard Moissl.

The agency put the chance of 2023 DZ2 hitting Earth within the next century at zero.