What we've done all of these years is very simple, is use the little tool, which is ask three whys in a row. Because the first why you always have a good answer for. The second why, it starts getting difficult. By the third why, you don't really know why you're doing what you're doing.

Well actually I was at home. I was doing some housework. So I was very surprised.

Have more than one idea on the go at any one time. If it’s a choice between writing a book and doing nothing I will always choose the latter. It’s only if I have an idea for two books that I choose one rather than the other. I ­always have to feel that I’m bunking off from something.

The great singer Um Kulthum (actually named Kawkab Elsharq – a superstar of the East) had a major influence on my appreciation of music. On the first Thursday of each month we listened to Um Kulthum's concert – "waslats" (three songs) – for more than three hours. During all of my study years in Egypt, the music of this unique figure gave me a special happiness, and her voice was often in the background while I was studying mathematics, chemistry… etc. After three decades I still have the same feeling and passion for her music.

I was very, very thorough, making sure I really understood how that telescope worked, and that it was working properly. I was quite convinced that I wasn't clever enough to be in Cambridge and would be thrown out at some stage. My policy was to work as hard as I could so that I'd know I'd done my best. We now label this as impostor syndrome, but we didn't recognise, and certainly didn't name it, back then.

They have a lot of extreme physics going on inside them and scientists use them to test theories of relativity on a cosmic scale. Einstein’s theories are checking out pretty well so far.

Yes, in 2018, I was awarded the Breakthrough Prize for the discovery. I was a bit dumbstruck, never expecting that kind of thing to happen. I was keen that the money should be used well and the best way to do that seemed to be to encourage a more diverse research student population from under-represented groups.

It looked like an agricultural frame, something you might grow peas up – a lot of wires and cables strung from posts over a space the size of 57 tennis courts. It was actually built to study radio emission from quasars. I built the prototype and then six of us took two years to build the real thing.

From one particular piece of the sky an unclassifiable signal sometimes recurred and my brain started to say: “You’ve seen something like this before, haven’t you? You’ve seen something like this before from this bit of the sky , haven’t you?” I got out previous recordings from that bit of sky. It often wasn’t there, but when it was, it was keeping its place amongst the stars.

The next generation of telescopes will see millions of events per night with computers that sift through huge amounts of data. If we had had access to a computer, we would never have programmed it to look for something so unexpected. How do you pick up the things you don't know exist, the things you can't tell it to look for? My project was to study quasars, and then we accidentally stumble over these things called pulsars. They were totally unexpected, totally unknown – and it's been huge fun.