When we began the practice of raising a glass to every near-Earth asteroid five years ago, we didn't realise quite what we were letting ourselves in for. This chart gives some idea of what we're up against, even given the fact we don't usually pop the cork for anything over 1.5 million km away.
(There's lots more discovery data at the source: NASA/JPL)
According to Universe Today,
As of May 30, 2014, 11,107 near-Earth objects have been discovered with 860 having a diameter of 1 km or larger. 1,481 of them have been further classified as potentially hazardous.To earn the designation of 'potentially hazardous', they need to approach within 7.48 million km and be at least 150m across; the sort of thing that would make a very nasty mess indeed should one ever turn up here. While every asteroid catalogued is one less unknown, there's something unsettling in the idea that we have only had a few days notice for most of the recent near misses.
While optimists talk of untold riches mining asteroids and plans are afoot to capture one and park it somewhere convenient, we should not forget the words of NASA's chief when asked what we could do if an asteroid were discovered to be heading straight for us: "If it's coming in three weeks, pray."
Anyway, if you're at a loose end with a glass in hand at 9pm (BST) tonight, the virtual telescope will be covering the flyby of the newly discovered 22-metre-wide 2014 KH39, which will be whizzing past 432,000 km above our heads at a decidedly nippy 25,000mph.