27 January – A small asteroid will pass within about 60,000km (roughly 37,000miles) of the Earth this afternoon, reaching its closest at about 16.00 GMT. This is one of the closest asteroid approaches ever recorded, but it poses no threat to Earth or to our geostationary satellites (which orbit at a distance of around 20,000km).
The asteroid has been named 2012 BX34 and is estimated to be about 11m (36ft) in diameter. Though it won’t be visible to the naked eye, keen amateur astronomers still have a good chance of sighting it.
Fortunately it’s very rare for large asteroids to strike the Earth – perhaps 60 objects greater than 5 km across have done so in the last 600 million years (or an average of about one every 10 million years). One of the most famous was of course the 10km-wide asteroid that may have led to the extinction of the dinosaurs 65 million years ago.
Smaller objects hit our planet more frequently – about 500 football-sized rocks strike the Earth each year.
Find out more about asteroids: