An asteroid roughly the size of a school bus will fly by Earth tonight, coming 30 percent closer to our planet than the moon – and scientists have only just noticed it.

Nicknamed ‘Rerun,’ asteroid 2017 BX will approach just before midnight (ET) on Tuesday night, travelling 16,600 miles per hour (about 26,700 km/hr).

Scientists discovered the object this past Friday, and they say it will be a ‘close shave’ when the asteroid passes within 162,000 miles of Earth.

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An asteroid roughly the size of a school bus will fly by Earth tonight, coming 30 percent closer to our planet than the moon – and scientists only just noticed it. Nicknamed ‘Rerun,’ asteroid 2017 BX will approach just before midnight (ET) on Tuesday night. Stock image

THE 'NEW' ASTEROID The ‘Rerun’ asteroid is roughly 13-46 feet wide. It’s moving at a speed of more than 16,600 miles per hour (about 26,700 km/hr), or 4.6 miles per second. The object was just discovered on January 20, and will make its closest approach to Earth at 4:54 UTC on January 25th (11:54 EST, January 24th). It will pass between our planet and the moon, coming 30 percent closer than our lunar neighbour at 162,000 miles away from Earth. Advertisement

While it may sound alarming, ‘Rerun’ isn’t likely to pose any threat to our planet.

Measuring between 13 and 46 feet across, it’s relatively small, and is expected to safely pass between Earth and the moon late tonight.

Slooh astronomers will be live broadcasting the event starting at 5:30 p.m. (EST), and they say ‘Rerun’ will make the closest approach at 4:54 UTC on January 25th (11:54 EST, January 24th).

The researchers will also be answering questions about the new near-Earth object (NEO), and explaining further details about its size, speed, and makeup.

And, on Twitter, they revealed they’ll be addressing a question that many are likely to be wondering: ‘How could something this size have gone undiscovered for so long?’

The asteroid was only discovered on January 20, and is an example of just how little we know about the potentially deadly NEOs flying through space.

Just weeks ago, an asteroid as big as a 10-story building passed by Earth at a distance half that of the Moon.

While it may sound alarming, ‘Rerun’ isn’t likely to pose any threat to our planet. Measuring between 13 and 46 feet across, it’s relatively small, and is expected to safely pass between Earth and the moon late tonight

The asteroid, dubbed 2017 AG13, was only spotted only days before by the University of Arizona's Catalina Sky Survey.

It is between 50 and 111 feet (15 to 34 meters) long, and when it passed by Earth on January 9, 2017, AG3 was moving at 9.9 miles per second (16 kilometers per second).

'This is moving very quickly, very nearby to us,' Eric Feldman, an astronomer with Slooh, said during a live broadcast of the flyby at 7:47 a.m. ET on January 9.

'This one has a particularly elliptical orbit.

Scientists discovered the object this past Friday, and they say it will be a ‘close shave’ when the asteroid passes within 162,000 miles of Earth. In the simulation above, asteroid 2017 BX can be seen approaching Earth in its orbit late last year

'It actually crosses the orbits of two planets, Venus and Earth.

Slooh's broadcast said 2017 AG3 was 'roughly the same size as the asteroid that struck Chelyabinsk, Russia in 2013,' meaning had it hit, the effects would have been similar.

Its next close approach to Earth is expected on December 28, 2017.

'It is not that uncommon of an event, which is one of the reasons it is interesting,' Mark Sykes, director and CEO of the Planetary Science Institute, told Business Insider in an email.

About 38 more 'close approaches' like asteroid 2017 AG3's are expected within the month of January alone, according to NASA's Near Earth Object Program.