Wicklow-born Dara Ó Briain, 45, studied maths and theoretical physics at University College Dublin. In the mid-90s he became a children’s TV presenter and standup comic. He has hosted panel show Mock the Week for 12 years, and also presents BBC2’s revival of Robot Wars and astronomy series Stargazing Live. He has now written a children’s book about space.

You’re currently writing your next standup show. How’s it going?

Slowly. I’m two months away from the tour so I’m staring at a wall of scribbles and half-formed ideas. The process is driven by failure and wine. But it basically gets written on stage. I’ve been doing low-key preview shows in Edinburgh, and it’s the prospect of failure that lights the creative fire. The cold, unamused stare of the audience is a great motivator.

Will you include topical material about, say, Trump or Brexit?

Trump won’t make the cut. You tend towards the universal and timeless. Trump is anything but. Events move too fast with him – I could write gags about North Korea, then suddenly it’s overtaken by Charlottesville or the solar eclipse. We cover him on Mock the Week, but it’s also difficult to satirise someone so inherently ridiculous. I’ve written a Brexit routine, though. That’s clearly going to drag on slowly and painfully for years, so that’s fine. [Laughs]

You’re also just about to publish a children’s book about space, Beyond the Sky. My eight-year-old son has been reading it and chortling away…

Oh fantastic, I’m delighted to hear that. I’ve had very little beta testing, as it were. It’s not like I could try it on my own kids. They’d just roll their eyes and walk away.

Kids are as tough an audience as any other. It’s been a fascinating process

Are your children unimpressed by you?

Of course, I’m just embarrassing Dad. The only thing that’s really clicked with them is Robot Wars. Our house is scattered with cardboard cutouts of robots. It’s back on TV in October, and this series there’s a 10-robot battle, so I got the kids along to the studio for that. There were 10 illuminated robots flying around the arena at once. It was by some distance the longest fight ever. By the end there was a huge robot pile-up in the pit, all still clanking and spinning. Even my kids conceded that was pretty cool.

How did the kids’ book come about?

The publishers approached me after seeing me on Stargazing. They thought my style would fit. Obviously I’m not going to write the sort of book that [co-host] Professor Brian Cox would. My job on Stargazing is to help communicate other, cleverer people’s ideas, rather than give my own view of my universe. I know enough to get by. Cox is the real brains.

Was it a challenge to write for children?

Kids are as tough an audience as any other. It’s been a fascinating process. The book’s unrecognisable from the manuscript I delivered. I wrote it, then handed it over for a sort of “kids book-imogrification”. They add cartoons and funny fonts, and suddenly it leaps off the page. It’s like seeing your words performed by an actor. It’s definitely for children, not one of those “for kids of all ages” books. If I saw an adult reading it on the train, I’d give them a stern look. [Laughs]

You’ve met a lot of astronauts on Stargazing. What are they like?

Astronauts are the most fantastic people you’ll ever meet but also the greatest pains in the arse. Whatever anecdote you tell them, they’ll have done a similar thing – but in space. They’re a chore to be around. To be fair, though, I’ve stolen lots of those stories. Like Buzz Aldrin ramming a felt-tip pen into the Apollo 11 control panel to replace a broken switch – he told me that, so I put it straight into the book.

Were you space-mad as a boy?

I used to recreate scenes from Flash Gordon – running around a 70s kitchen with a colander on my head for a space helmet – but my passion for science really took off when I was 14. I read In Search of Schrödinger’s Cat by John Gribbin, then Chaos by James Gleick and later, Stephen Hawking’s A Brief History of Time. That was what fired it all.

‘Pretty cool’: Dara Ó Briain in Robot Wars. Photograph: Alan Peebles/BBC/Mentorn Media Scotland/Alan Peebles

You interviewed Professor Hawking two years ago on BBC1. How was that?

Mind-bogglingly brilliant. A career highlight. There was none of that “never meet your heroes” syndrome because he was a delight. It was difficult in the sense that it’s slow to communicate, with these long pauses while he comes up with a response. I was burbling and floundering around awkwardly, but after it aired I met some people from a motor neurone disease charity and they thanked us for leaving that bit in, because people don’t know how to handle it. It’s important to show that it can be uncomfortable and that’s OK.

Did you stargaze in childhood yourself?

A bit. I had a nerdy little relationship with Ursa Major. Wherever I was, I would look up to it. When I was putting the bins out, it was like a scene from Annie: “Poor little me, made to do chores, but I’ll always have the Plough, my friend in the sky.” There’s a weepy Irish space musical in this. [Laughs] I also remember the first time I saw the Perseid meteor shower. I was studying for my physics finals in the shed one night, went out into the garden to have a think, then looked up and saw shooting stars over my head. That was a nice moment. There’s your rousing finale for the musical.

My son loved the stuff in your book about astronauts’ toilet habits…

The way that wee gets turned back into drinking water and poo gets dispatched back down to Earth? If you ever do a school assembly about space, that’s the first thing kids want to know. How do you do normal things up there? Specifically, how do you poo and wee? There’s real fascination for that stuff. So poo is a gateway drug, then I hit them with the cosmology. Come for the poo, stay for the black holes.

Which children’s books do you rate?

We’ve done all the Wimpy Kids, Tom Gateses, Philip Pullmans and Harry Potters. I’m gently pushing my two towards the classics, so we’ve been reading Oliver Twist recently. The language is dense but we’re ploughing through it. The two things that keep tripping us up are Fagin being repeatedly referred to as “The Jew” – yikes, that was an interesting teaching moment – and the character called Master Bates. It’s like that urban myth about Captain Pugwash.

What are you reading at the moment?

I flit between lit-fic and factual. Right now, it’s A Horse Walks into a Bar by David Grossman, which is excellent, and Robert Webb’s new book, How Not To Be a Boy, which I’m also enjoying. My all-time favourites are Philip Roth and Peter Carey. I bought a signed first edition of Oscar and Lucinda in Dublin last week, then got home and realised I already had two copies. So I’m well served for Oscar and Lucindas. One for every floor of the house.

You’re a guest judge on Channel 4 contest Lego Masters. Are you a big Lego fan?

Hell, yeah. You can’t beat that satisfying brick-to-brick click. I still remember the milestone moment I sold my Lego to buy a Commodore 64. Did you see that story recently about David Beckham making a Lego Disney castle for his daughter? Everyone thought that was cute but he built it when she was in bed! Surely the idea of Lego is that she makes it? The whole point is building. It’s like, “Look, I’ve finished your toy. Oh, and I bought you some paints but I’ve already painted a picture and used them up.” It’s a really weird thing to do.

Speaking of footballers, you’re an Arsenal season ticket-holder. Are you Wenger in or Wenger out?

I’m Wenger shake it all about.

You caused a chip shop controversy recently…

[Laughs] I discovered this place in Dublin that serves chips with peppercorn sauce, which was awesome, and tweeted, “This changes everything.” Except everyone got in a tizz about what I called the chip shop. I always say chipper but apparently in Belfast they say chippy. An Irish newspaper had an online poll and everything. It wasn’t vive la difference, it was “You, sir, are incorrect!” Chips can drive a wedge between us in a way that Brexit never will.

Beyond the Sky by Dara Ó Briain is published on 7 September by Scholastic (£12.99). To order a copy for £11.04 go to guardianbookshop.com or call 0330 333 6846. Free UK p&p over £10, online orders only. Phone orders min p&p of £1.99.