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Ger Deering is Ombudsman and Information Commissioner for Ireland.
*****
Call me a nerd, I went to see the eclipse.
None of your 94 per cent stuff, I went to Spain for the total eclipse, I found a spot at in a mountain village in Catalonia, silly glasses and all, and watched while the moon slowly took a chunk out of the sun, like a bite from a cartoon biscuit, and the bite got bigger and bigger.
I had been planning to see this for about three years, and booked the flights and accommodation well ahead of the rush.
And I can confirm that a total eclipse of the sun is a completely different thing to anything short of 100 per cent. Apparently it’s because your eyes adjust to the untimely twilight, so even with an almost total eclipse, things on the ground don’t look so different. But then in an instant when the moon totally blocks out the sun, the Mediterranean evening went pitch black. The street lighting in my mountain village was either dumb enough, or smart enough not to switch on.
This left the only thing dominating the sky a black circle where the sun should be, surrounded by the flaming corona, the atmosphere of the sun that is normally invisible, washed out by the light of our home star. You can well understand why a prehistoric hunter-gatherer or medieval peasant would fall to their knees in terror if they witnessed this unexpectedly.
The celestial light switch was flicked on again, and normal service was resumed one minute and 39 seconds later. This tells us a lot about science – and I don’t mean the specific sciences of astrophysics and orbital mechanics, I mean about the first principles of science. Three years ago, I was able to look up the exact locations where the eclipse would fall. For any point on the Google maps overlay, you could see the exact time, accurate to one tenth of a second, that the eclipse would begin and end. For any point on the map you could look up the exact time, accurate to one tenth of a second, that the blackout of totality would begin and end, as it swept in a wide arch from Iceland down the Atlantic, missing Ireland and crossing Iberia from the Basque country to Catalonia.
I looked up that information three years ago, and you can go on the same website now and look it up for the eclipse that will cross the Antarctic in 2030 if you feel like long-range planning an exotic holiday.
What strikes me about that is the sheer accuracy of it. It takes an incredibly precise measurement of the rotation of the earth, and the orbit of the both the earth and the moon to calculate, years in advance, the exact tenth of a second when this exact spot on the surface of the earth will be line up with that exact spot on the surface of the moon 400,000km away just as it perfectly obscures the sun 150 million km away.
And that’s science. Not the calculation – that is a specific scientific endeavour, and a fantastic one. But science as a concept is making predictions. Any shaman or priest can tell a prehistoric hunter-gatherer or a medieval peasant that that eclipse meant that god was warning them, the shamans and priests can have all sorts of opinions, sometimes convincing, about the meaning of past events.
But only science can predict the future and tell you that this spot on the side of this hill in Catalonia, or the coast of Antarctica will fall into darkness at an exact time, accurate to one tenth of a second, years before the event, and get it right.
Or get it wrong and scrap that hypothesis and start work on another. If it doesn’t make testable predictions, then it’s not science; and if those predictions don’t come true, then it’s wrong science. That’s something to remember in the days of alternative facts, and our own personal truths, or as we used to call them, lies.
