The conspiracy theorists and panic-mongers are having a fine time with NASA’s plan to crash a rocket into the Moon at 12:30 today. Will it be the end of the world as we know it? Hardly. That little world suffers a good dozen similar collisions every year and the craters we see from here show it survives impacts that dwarf one piddly rocket.
Coincidentally, I've just read about the meteorite that hit Chicxulub 65 million years ago, at the end of the Cretaceous Period. That was a crash.
I can only get my head round it this way. Imagine taking a Redditch-size ice-cream scoop out of the planet, preferably Redditch itself. There's your meteorite, more like an asteroid, what? Now fire it out of a great big gun, let's say at South Wimbledon, another shite place where I’ve lived.
On a planetary scale hurling Redditch at a bit of London is pretty small beer – just a pinprick on the globe – but if you were anywhere near it... how near? Most of us have felt that satisfactory thump of something quite big going off, like a huge firework. Imagine a house going off then, or a plane (I’m sure we can all do this), or an office block, then a complete town. You’d get out of the immediate neighbourhood.
So now, how far? Well, the Chicxulub impact threw up instant Himalayas ninety miles away. Curiously, that's Redditch distance. That's Coventry too. See how I've got it in for some places? Actually that's the entire south-east of England done for and it doesn't end there. Wikipedia fills in the next few moments better than I could.
It also posits a tsunami because Chicxulub at that time was on a continental shelf. Look at the height of this wave though – half a mile to a mile. The recent ones in Samoa and more distantly Indonesia, terrible as they were, didn’t even crawl out of the cradle in comparison.
Not much to do with birds but, of the dinosaur family, they may be the only survivors from the mass extinction that followed. The meteorite might not have been the sole culprit: the ecosystem was already under stress from a vast series of volcanoes separating India from Madagascar. In any case the Tertiary Period and large mammals were on their way in. That was the K-T Boundary that was.
I don't think we'll get the same show from NASA’s rocket.