15 June

2002: On 15 June 2002, an asteroid the size of a football pitch made one of the closest ever recorded approaches to the Earth. It is only the sixth time an asteroid has been seen to penetrate closer than the Moon's orbit, and this was the biggest rock to have done so.

The space object was only detected on 17 June. It was found by astronomers working on the Lincoln Laboratory Near Earth Asteroid Research (LINEAR) search programme in New Mexico, USA.

Catalogued as 2002MN, the asteroid was travelling at over 10 kilometres a second when it passed Earth at a distance of around 120 000 km. The asteroid has a diameter of between 50 and 120 metres. This is actually quite small when compared with many other asteroids and incapable of causing damage on a global scale. Nonetheless, an impact from such a body would still be dangerous.

The last time such an object is recorded to have come this close was in December 1994.

Space-based telescopes, such as NASA/ESA Hubble Space Telescope and the future ESA Gaia mission, are at the moment, the only means of searching for asteroids in the daytime sky.