© Nasa/JPL
2011 GP59 orbit.
Amateur astronomers across the world have fallen for a cheeky asteroid that passed the Earth on Monday night.

Asteroid 2011 GP59 was caught winking at our planet from a distance away barely 10 times that of the moon.

The "winking" bit which is getting spacefans so hot and bothered stems from the fact that the asteroid is cigar-shaped and spinning madly end-to-end, comparatively speaking.

"Usually, when we see an asteroid strobe on and off like that, it means that the body is elongated and we are viewing it broadside along its long axis first, and then on its narrow end as it rotates," said Don Yeomans, manager of NASA's Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, California.

"GP59 is approximately 50m long, and we think its period of rotation is about seven-and-a-half minutes.

"This makes the object's brightness change every four minutes or so."

Don't believe Don? Check out Essex star-botherer Nick James's video of 2011 GP59 cruising past some 3,356,000km away.

That's about 10 lunar distances - our moon is 384,400km away - but tomorrow morning, about 5am, things get a little crazy.

For start, Monday's night's discovery of GP 59 was just that - a discovery.

It was picked up by astronomers at the Observatorio Astronomico de Mallorca in Andalusia, Spain, who've since determined that it's heading towards us.

Tonight, it will pass just outside the moon's orbit - again, comparatively speaking because this is space, folks - at a distance of 533,000km.

However, Mr Yeomans, whose office is responsible for a program called Spaceguard, which tracks and characterises asteroids and comets and is supposed to protect us from this sort of thing, says there's no need to be concerned.

"Although newly discovered, the near-term orbital location of asteroid 2011 GP59 can be accurately plotted," he said.

"There is no possibility of the small space rock entering Earth's atmosphere during this pass or for the foreseeable future."

Which is good news, because although 50m might sound smallish, it's still five times bigger than an asteroid that exploded 15km above Indonesia in October, 2009.

That blast released as much energy as three atomic bombs, according to New Scientist, who are supposed to know about such things.

Take comfort in the fact that in 2009, no one saw that asteroid coming. At least we were given three days' notice this time around.

So that's something.