The UN Action Team on near-Earth objects, which has taken note of the 460-ft asteroid, placed the odds of its hitting the earth at one-in-625, though that could change nearer the time.
Scientists have not yet been able to work out much more about it than its size as they have only been able to observe it for half its orbit. But between 2013 and 2016 they will be able to monitor from the ground and will make a more detailed assessment.
In 2023 the rock will make a 'keyhole pass' of Earth, which is an area it passes through on the orbit before it would hit Earth. This will be within a mere 0.02 astronomical units of our planet, or 1.86 million miles, according to NASA's Jet Propulsion Lab.
NASA's infrared sky-scans track space objects such as asteroids. A recent scan with the NeoWISE instruments found that there were 19,000 'mid-sized' asteroids within 120 million miles of Earth, the Daily Mail reports.
According to NASA, among the ways of deflecting it are putting a probe onto the rock and using the extra gravity the craft generates to steer the asteroid away over millions of light years. Another option would be sending a probe into it so that the impact has the same effect.
Nuclear weapons have also been discussed, but this would create a shower of rocks instead of just one.
Mid-sized refers to asteroids in a size range between 330 and 3,300 feet wide, which could destroy a city-sized area were they to hit Earth.