I seem to spend most of my time these days debunking ‘health threats’ of one sort or other: tobacco smoke, alcohol, obesity, global warming, to name a few.
So it’s a bit strange to find myself taking another ‘health threat’ very seriously: the threat of rocks raining down from the sky, and exploding like atomic bombs.
I suppose that I think that atomic bombs really do pose a genuine health threat. Particularly when they start landing everywhere out of the blue.
But apart from the Russians, nobody else seems particularly bothered about them.
You’d think that, in a world in which SHS is perceived as a tremendous threat to human health, that rocks raining down from the skies and exploding like nuclear bombs would be seen as an even bigger threat.
But no, it doesn’t work like that. It seems that when people play up minuscule threats (like that posed by SHS), the flip side is that they’ll play down real threats.
It has seemed horribly complacent of a number of astronomers to compute a possible orbit of the Chelyabinsk asteroid, and conclude that it came from the asteroid belt, and had nothing whatsoever to do with asteroid DA14 that arrived the same day – and ignore all the other fireballs seen in the skies around that time (two in Russia, two in Japan, one in Cuba, one – possibly two – in the USA).
They worked out the orbit by studying the many videos of the Chelyabinsk fireball, and calculating its direction and angle of impact and speed, and then working backwards from there to an asteroid belt origin.
Yet all their estimates would have been imprecise. They would have said that the speed of the fireball was 20 km/sec ± 0.5 km/sec, or something. And the same kinds of ± numbers for the direction, and the angle of descent. They most likely took mid-range values of every variable, and said those were the most likely values, and so that’s where it came from. And now that orbit has been broadcast all around the world, and has become the official story: the Chelyabinsk meteor came from the asteroid belt, and it was a complete coincidence that it arrived the same day as DA14.
I adopted a very different approach. I noted that there’d been 7 or 8 (maybe more) fireball sightings in a 3 day period around 15 February, and supposed that there was a cloud of rocks around DA14, travelling alongside it, and it was some of these that came raining down over those few days.
This possibility was dismissed at the time, both by NASA and ESA, on the grounds that DA14 was approaching Earth from below its South Pole, and so accompanying fragments couldn’t have landed in the northern hemisphere.
But, using my own simple orbital simulation model, I’ve managed to get such fragments to land as far north as 49°N. Chelyabinsk is 55°N. And I think I can see, in principle, how all the reported fireballs could have been Earth-skimming meteors that curved up over the equator, and part way round the Earth’s northern hemisphere.
But a DA14 fragment cloud is a hypothetical entity. Nobody’s actually seen it. And it might not be there. I’ve been testing a hypothesis, and working forward from hypothetical locations and velocities in space to an impact point near Chelyabinsk. But the astronomers who figured out the asteroid belt orbit were working backwards from Chelyabinsk. They might have said that they were doing “evidence-based science”: they looked at the evidence that was available – videos, eyewitness reports, etc – and just used that. They didn’t make any hypothesis at all.
And they’re the experts. I’m just a filthy smoker with a clunky computer simulation model that I wrote myself. So when it comes to who to believe, pretty much everybody is going to believe the experts.
But, once again, I think the experts are wrong. And, worse still, I suspect that – just like lots of other ‘experts’ – they actually came to a pre-determined conclusion. They probably believed from the outset that the Chelyabinsk fireball came from the asteroid belt, and when they found that some combination of their numbers gave them an orbit that passed through it, they picked that one.
And it was a politically convenient orbit, because it meant that it was just another lone rock coming in from the asteroid belt, that nobody could have foreseen. Because if they’d concluded that it came from a rock cloud around DA14, people would have said that it was predictable, because DA14′s close approach was predicted a year back, and that the possibility of a rock cloud around DA14 should have been predicted too, and NASA and ESA and all the other space agencies had let the whole world down. Heads would have rolled. So they couldn’t come to that conclusion, could they? And indeed they didn’t.
I pretty much expect, these days, that almost all health scares (like SHS) are politically motivated. Global Warming too. It’s all pretty soft science, after all. But I’m now beginning to think that the rot goes much deeper, and it has infected the hard sciences as well. And the rot always seems to set in whenever any probabilities are involved, because when numbers become probabilistic, it becomes possible to pick and choose which numbers to use. Given that all numbers are equally probable, you can choose whichever one you like. So you choose the ones that point to secondhand smoking as a health risk, or an asteroid belt orbit for the Chelyabinsk fireball.
It becomes roulette science. You place your chips on number 17. Or odd numbers. They’re all equally likely, or unlikely. And you have to place your money somewhere. And so once the wheel is spinning you’ll be rooting for 17, or for an odd number. Because there’s money riding on that wheel, and you have a deep interest in it. You’re not a disinterested observer any more. It’s win or lose, you or me. And all our scientists have become roulette players, with their money on some number in a roulette game. They have a personal interest in the outcome.
But I have no money down. It doesn’t matter to me whether the Chelyabinsk meteor came from the asteroid belt or not. I’m not going to lose out if it did. But it seems to me that it almost certainly didn’t.