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Earth 'near miss' with asteroid the size of a mini bus explained - all you need to know

An asteroid passed within 2,200 miles of Earth's surface on Friday. Here's all you need to know about this special space event.

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An asteroid has passed very close to Earth, passing just a few thousand kilometres above the planet's surface.

The relative near miss was streamed live using robotic telescopes - here's what you need to know about the asteroid and how you can watch it.

What do we know about this asteroid?

The asteroid was first spotted on 21 January and has been named asteroid 2023 BU.

NASA said before the event "a small near-Earth asteroid will have a very close encounter with our planet" as it "zooms over the southern tip of South America".

It was due to whizz past Earth shortly after midnight on Friday 27 January.

At its closest point it was 2,200 miles above Earth's surface. That's less than 3% of the average distance between the Earth and the moon.

It may sound like a long way, but this asteroid was the fourth closest to pass by Earth since records began.

By comparison, some satellites orbit at an altitude of more than 21,000 miles.

Should I be worried about the asteroid crashing to Earth?

In short, no. The asteroid is between 3.8 and 8.4 metres in size - small enough to incinerate on entering Earth's atmosphere.

Apparently it's roughly the size of an elephant.

According to NASA, asteroids smaller than 25m are likely to burn up, leading to little or no damage on the ground.

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Asteroid near miss was streamed live

The Virtual Telescope Project started broadcast the close encounter live from 7.15pm on Thursday 26 January.

Astronomer Gianluca Masi hosted a free livestream on the project's website and YouTube channel.

The Virtual Telescope Project is run by the Bellatrix Astronomical Observatory in Italy and consists of several robotic telescopes that are accessible online.

What is an asteroid?

An asteroid is a "relatively small, inactive body orbiting the Sun", according to NASA. It's normally made of rocky, dusty, and metallic materials.

Most orbit within the main asteroid belt, between the orbits of Mars and Jupiter, but some follow paths that circulate into the inner solar system (including near-Earth asteroids).

A NASA website displays the next five asteroid approaches expected near Earth, showing how they are typically extremely far away. Sizes of asteroids range from around the footprint of a house, to a bus or plane.