Earth narrowly dodged another cosmic impact today when an asteroid the size of a small house skimmed past. The chunk of space rock, which was only spotted hours two days earlier, flew by at around a quarter of the distance of the Moon. 

Dubbed 2013 LR6, the asteroid passed only 105,000 km above the Southern Ocean, south of Tasmania, Australia, at its closest approach at 4.42 UT.

With a diameter of around 10 metres, it was only discovered as incoming on Thursday. It was detected by a NASA-sponsored monitoring operation by robotic cameras called the Catalina Sky Survey, based in Arizona. Its mission is to discover as many of the asteroids as possible with orbits that cross the Earth’s.

Most of the hundreds of thousands of asteroids circle the Sun between the orbits of the planets Mars and Jupiter. But more than a thousand are known which jaywalk across the Earth’s path through space. They are described as Potentially Hazardous Objects.

Asteroid 2013 LR6 is around half the diameter of an asteroid that exploded spectacularly over the Russian city of Chelyabinsk on February 15 this year, causing widespread damage.

By coincidence, that collision occurred on the very day that a 50-metre wide space rock labelled 2012 DA14 made the closest near-miss ever predicted in advance for an object so large. It missed us by just 27,650 kilometers (17,150 miles) above the Earth, bringing it inside the orbits of TV and communications satellites.