Friday, 5 March 2010
It's the Final Countdown
So it’s official. The dinosaurs, along with much of the larger life forms on land and in the air and the seas, were wiped out by a large asteroid colliding with Earth. A panel of experts (heaven help us) have concluded that the Cretaceous-Tertiary mass extinction, around 65 million years ago, was not due to the million odd years of volcanic activity in the Deccan Traps in India, where mega eruptions spewed more than 1,000,000 cu km of basaltic lava out of the earths interior. No, it was a 15 km mountain travelling at 20 kps that messed up the dinosaurs’ long term career plans.
The space missile slammed into what is now Mexico's Yucatan Peninsula. The resulting crater, Chicxulub, which was 180km in diameter, must have been something – an explosion equivalent to 100 trillion tonnes of TNT. Pretty awe-inspiring (or frightening) it has to be said.
Although this can only be described as a catastrophe for the dinosaurs, it was good news for you and I. Wiping out the big nasty lizards, allowed the small mammal-like creatures to move out of their niches and colonise the planet; and, after a time and Darwin, evolve into the likes of Brad Pitt and Angelina Jolie.
Scientists reckon that these interstellar road accidents occur once every 100 million years. Since this one took place 60 million years ago – we’re safe for another 40 million years – right. Not exactly, it could take place within our life-time.
The Americans are particularly keen to ensure that if something like this is going to happen, they’ll be the first to know. I suspect it’s because the last one fell in their backyard, and their homeland is pretty big and relatively densely populated. Also, as we know from any US block buster, if anything bad is going to happen it’s going to happen to the US first.
As well as looking at the pretty stars in the sky the Americans, and others including us, are scanning the sky for early indications of rogue asteroids or comets which might be heading our way. If they find that one is, I’m not sure what can be done. I suppose it depends on how much warning we have, how big the thing is and the level of our technology. In simple terms, we’ll need to stop the thing hitting us at all or as a single massive mountain.
We could divert it by strapping huge rockets to the rock and changing its course. A large explosion let off at a suitable distance from the menace could have a similar effect. Alternatively we could fire a massive laser at it, vapourising part of the rock and the resulting stream of particles and gases would act as a rocket and push it onto a different course. Others suggest going for the big bang approach and smashing the rock into thousands of smaller pieces which will continue to Earth but will burn up harmlessly in the atmosphere.
The trouble is we’re likely to have only one shot and things being what they are – it’ll go wrong and we'll be left staring up at the sky watching this mountain getting closer and closer and closer until…..
It would be a fantastic display: although probably incredibly frightening and messy – especially after land fall or splash down. And of course as top beast on the planet we’re more than likely to be wiped out. Leaving room for other species to colonise all those places we loved so much.