My parents split up when I was four. I sometimes lived with my mum, sometimes with my dad. At one point my mother lived above a sweet shop, which was exciting – BlackJacks and Fruit Salads were half a penny each – then she married a vicar. My diet changed, from my father’s traditional Nigerian food to the more English cooking of my mother. Maybe because I comfort ate, I put on a lot of weight at my mother’s. When I moved back to my father’s, I lost it.

I went to 13 different schools while I was growing up, which made me very adaptable to most things. I loved hot sweet tea at home, but then went to boarding school aged seven and exclaimed, “This isn’t tea! It tastes like dishwater.” And Nigerians don’t traditionally eat salad or veg, so I’d say, “Some of those leaves, please.”

My father made all the dough for Pizza Express restaurants, then he was the manager at the Hampstead branch. For a while we lived above it – Dad and us four sisters. They’d give us pizzas and we’d leave them a penny and say, “Keep the change.”

At the Gemini observatory, on the summit of the Cerro Pachón in Chile, I was living alone in a bungalow next to the telescope. I had a little sandwich-maker which I could grill meat and fish on. Then I’d go out and eat with the moon. I’d have at least one slice of supermarket lemon meringue pie each night. With Chilean wine, of course. I’d say, to myself, “I won’t have another glass until I’ve seen at least 10 stars.”

I have a very severe dairy allergy. I can cook dairy, but if a splash gets in my eye, for instance, it will swell up. If I ingest even a tiny amount, I’m in real trouble – my throat will swell up and I can’t breathe, or I’ll be violently sick. It began after I gave birth to my daughter Laurie. When pregnant the immune system is suppressed, so your body won’t reject the foetus. It’s supposed to go back to normal afterwards. My whole diet has been modified. I’m usually armed with loads of napkins in case my daughter has a dripping ice-cream cornet.

We made little citrusy cup-cakes the other day with phases of the moon on them – dairy-free, of course. I also make my daughter’s birthday cakes. I’ve made her a Peppa Pig cake, a rainbow cake, one with an ice palace, one based on the film Frozen, with help from YouTube and a mould. That was a blue three-tier cake with icing-like glass on top. I get horribly carried away but it’s a way of expressing love with food.

There may be aliens out there who would find us tasty. But I think most would consume vastly different things to what we’re eating. When we were discovering a lot of Jupiter-like planets – gas giants with no rocky cores – I was asked to come up with the concept of an alien. I came up with these giant silicon-based jellyfish who communicated by light scintillations and sucked in the atmosphere, mainly methane, for sustenance.

There are 200 to 300 billion stars in our galaxy, so I’m convinced there are aliens out there. In the last 12 years, I’ve told this to 300,000 kids in my live shows. One of the other things that’s fascinated them recently is how, like in the film The Martian, you could use your poo on Mars to grow food to survive. It needs verifying.

I think 3D food printers will probably be in our home kitchens within 20 years. I’d take a Jamie or Gordon recipe and punch it into a printer, with the non-dairy variations and substitutions I require, and then dinner would be served. It might be a sad day for real cooks, but you could have both – the retro, real and instinctual, and the modern and “printed”.

At the VLT European telescope facility, there are French chefs with little hats cooking up wonderful things for us astronomers, who are more appreciative and romantic than many people give them credit for.

My favourite things

Food
This year it’s been scallops fried up lightly with a lump of spicy chorizo. A nice combination. It’s surf and turf I suppose.

Drink
I’m addicted to Ribena, but recently I’ve not liked it on its own. So I add crème de cassis on ice, which is delicious. Getting the right proportions is always the key. I suppose that’s true of most cooking.

Place to eat
The Watts Gallery in Guildford . It’s where my husband proposed. It’s so peaceful and beautiful, next to a graveyard, it’s all art deco and they sell fantastic cakes and hot chocolate – for those still un-allergic to them.

Signature dish
Over the years, I’ve often made Jollof Rice. With one ‘f’ I believe, although with my dyslexia I wouldn’t entirely trust that spelling. It’s rice, veg and chicken cooked together and it’s lovely.

The Sky at Night: Book of the Moon by Dr Maggie Aderin-Pocock (£9.99, BBC Books) is out now. To order a copy for £8.59, go to guardianbookshop.com