So here I am, innocently reading for review a book called What if the Earth had two Moons? when I come across a denouncement of the usual explanation of why the tides are the way they are. As an author, when you can point out a commonly held misunderstanding, it's very satisfying. So, for instance, when I was able to write in The Man Who Stopped Time that most websites and many books got it wrong in ascribing the mechanism for us seeing cinema as moving pictures to 'persistence of vision' (a Victorian concept that was just plain wrong) I felt rather smug. But here was a book denouncing the explanation I'd given for the tides in a book due out this April.
|My version of the tides (not to scale)|
One small consolation. I've just spotted a mistake in What if the Earth had Two Moons? The author says 'We can only see objects today that are within 13.7 billion light years of Earth.' This would be true if the universe weren't expanding. But because of this the objects we can see whose light has been travelling nearly 13.7 billion years are actually getting on for 40 billion light years away. I don't say this to get my own back, just to point out how easy it is to slip up.