Of all the animals of prey, man is the only sociable one.
Every one of us preys upon his neighbour, and yet we herd together.
The Beggar's Opera: John Gay

Sunday, 22 July 2012

Yippee! It's asteroid time again!


OK, so it's passing by 14 times as far away as the moon, but here at the tavern, a fly-by is always an excuse for a party.

3.2 million miles away may be uncomfortably close on an astronomical scale but 2002 AM31 is unlikely to put a spoke in Lord Coe's plans when it sails past just after midnight tonight, however appealing the prospect.

Still, it's good to see the astronomical establishment considering the apocaholic point of view for once:
Astronomy magazine's Bob Berman says, ‘Near Earth objects are no longer treasures only for the paranoid, or for those who secretly and strangely are rooting for an early apocalypse. [...] These are important entities. Not to mention, there’s always that exciting little hint of danger.
It's one of those odd statistical things; the chances of a substantial asteroid hitting us at any particular time are very small but the consequences if one does are so immense that it becomes a significant risk.

That one will hit Earth some day is a certainty. Recent estimates suggest there are around a thousand lumps of rock measuring over 1km across in orbits that intersect or approach our own, each with the potential to obliterate a country the size of England.

As a rough rule of thumb, a pea-sized fragment hits our atmosphere every 5 minutes, and a football-sized rock every month or so. We can expect something a little larger a couple of times a year and, every few centuries, something in the order of 40-50m across, the last one recorded being the Tunguska impact in 1908 (unless you believe that was an alien spacecraft, in which case you are probably reading the wrong blog).

With all this cosmic pinball going on, it is, perhaps, a shame that our own prophet of astronomical impact, Lembit Opik, has wandered from the true path, drawn into the orbit of some rather more earthly bodies, and abandoned his calls for research into asteroid detection and early warning systems.

Other nations are doing their bit, however; and it turns out that there are plenty of near misses - give or take the odd hundred thousand miles - from rocks we had no idea existed. While those of a nervous disposition might prefer not to know, we have truly entered a golden age for apocaholics, where the hellfire-and-brimstone of religion has been replaced by the strangely comforting ultimate certainly of celestial impact.

So, ladies and gentlemen, please raise your tankards and wish 2002 AM31 many happy returns!

2 comments:

  1. Puts things into perspective doesn't it? Yet once upon a time I'm sure we all knew about risks such as this - natural catastrophes we may plan to mitigate but are powerless to prevent.

    The climate change nutters seem to have skewed our thinking about natural catastrophes.

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  2. Perhaps some of the blame for this can be laid at the door of the BBC-approved line on climate change that now pervades all their natural history and science programming.

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