Of course, when I say close, I mean a mere 960,000 km away - two and a half times as far as the moon - but, when you're talking about a lump of rock up to 250m across, that's just a whisker in astronomical terms.
If there seem to have been a lot of the things about lately, that's largely because of the recent efforts of a number of observatories; of the ten close approaches last week (less than 30 million km away), five were by asteroids discovered in 2013.
The aim is to ensure that, should the Big One be headed our way, we get enough notice to do something about it. Former astronaut Ed Lu, CEO and co-founder of the B612 foundation dedicated to this cause, is optimistic that, given time, human intervention could deflect an earthbound asteroid.
After all, as he points out in an interview for Slooh.com, it's not as if we have any alternative:
"If you only have weeks or months, our only real practical thing we can do is evacuate the area. Now, if it's a large enough asteroid, we can't evacuate the earth. It's tough luck. And I personally think that as citizens of planet Earth we can do better than that."Unfortunately - at least for those of a cynical disposition - Dr Lu seems to be of the opinion that that answer lies in global cooperation in the face of a mutual threat to humanity. To a scientist, it makes perfect sense:
"When something big - half a kilometer across - is going to hit the Earth, it's in everybody's best interests to move it."I wish I shared his faith in human nature and the ability of politicians to see reason and act in concert for the good of mankind. The threat of global thermonuclear warfare may have abated but it's a sobering thought that we could all go the way of the dinosaurs because our political masters can't agree.