It’s half past eleven when I arrive at Sir Patrick Moore’s rambling house in the village of Selsey, West Sussex – an hour too early for his daily gin and tonic. He looks crestfallen on hearing this and begrudgingly agrees to a glass of orange squash instead. He is not much of a drinker. He proudly tells me that no one has ever seen him drunk in all his 89 years – “Well, once, but that wasn’t my fault. I had some special tablets and I didn’t realise you weren’t supposed to drink with them.”

His modest daily tipple is one of the few pleasures he has left. The renowned astronomer is wheelchairbound and arthritis prevents him from using his telescope.

In the corner of a study festooned with certificates from NASA, the BBC and the Royal Astronomical Society, sits the 1908 Woodstock typewriter on which, until two years ago, he typed the manuscripts for his hundreds of books and articles. “With two fingers, I could do 90 words a minute – not ever so fast but now, when I try to use the computer, I miss the keys. I tend to dictate instead.”

Why he chose to use a typewriter in defiance of the modern world remains a mystery, much like his trademark monocle which, I’ve just noticed, is absent. “It’s for outdoors,” he tells me, somewhat cryptically. He has worn a monocle since he was a teenager – a born eccentric.

“People couldn’t believe a 17-year-old boy had a monocle!

But like the typewriter, it was just right for me.”

We have met to discuss Sir Patrick’s new book, the endearing Miaow! Cats Really Are Nicer Than People, which features dozens of pictures of him and his much-loved cats Jeannie (now deceased) and Ptolemy, who sleeps on his pillow every night. In lieu of family (a regret we will come to later), he lavishes affection on his feline friends.

A sign on the front door announces: “This house is maintained entirely for the convenience of our cat.” It isn’t a joke. “People are never predictable but cats are always the same,” he writes, “and I find it comforting to know that they will always be there waiting for me.”

He grew up with cats and they are a link to his beloved mother Gertrude, to whom he was devoted. When a previous pet, Smudgie, died some years ago he tells me he was so upset he had to be sedated. He remains “heartbroken” over the loss of Jeannie. “I’d like to get another but my vet tells me Ptolemy wouldn’t like it and he comes first.”

Moore has never married.

He was 20 when his fiancée Lorna was killed by a German bomb that fell on an ambulance she was travelling in during the Second World War. Her death crystallised his hatred for Germany, which remains as strong today as it was then. Just recently he warned we should be on our guard in case “they” started another war and expressed his belief that “the only good Kraut is a dead Kraut”.

There was never anyone else for him but Lorna, and not a day goes by when he doesn’t think of her. He “can’t wait” for the day they are reunited in the afterlife, he tells me.

While not religious as such, “It’s just something I’ve always believed in.

When Lorna was killed, I remember saying I wouldn’t ever marry. She and I were devoted to each other – why split up? So we never did.”

Still, the scientist in him has made plans to prove his theory. When he dies, he has left a sum of money towards a great feast for his friends. He has arranged for a candle to be lit and a record played – “and when the right moment comes, I’ll blow it out!” He chuckles.

“I’ll do it if it kills me!”

Sir Patrick will turn 90 in March next year. He says he has had a “varied life”. Lined up for prep school, Eton and then Cambridge, heart problems kept him at home until he was 15.” I was a sickly boy, father. He was very strong, a champion boxer, a county hockey player… but then he swallowed a lungful of German gas. He was the most unlucky man.”

When war broke out, Patrick, then aged 16, “fiddled his way” into the RAF.

“By the time I came out, things were different. I wrote my first book and there we go.” He regrets never having had a family and, lately, he has missed being able to play or write music. He was once a gifted pianist.

Of his many achievements, he is modest. All he will say is that he hopes he has succeeded in drawing people into astronomy – “and especially youngsters”. He has presented the BBC’s Sky At Night for 55 years (latterly from the study we are sitting in), making him the corporation’s “most durable” presenter.

But he puts the programme’s astonishing longevity down to its subject.

“We live in the universe and we can’t help but be fascinated by what’s out there and what it’s all about.”

He points to a collection of small blue books embossed with The Story Of The Solar System. “I was given those when I was seven years old.

I was hooked from that moment on.”

He remains fascinated to this day. There is still so much we don’t know, he says.

“If you ask me how big the universe is, I’d say, ‘I’m sorry, I can’t tell you.’ Neither can Einstein and I know because I asked him!” Sir Patrick once played piano with the world famous thinker.

“I found him exactly what I expected: unworldly, communicative and blissfully unaware of his unique status.”

He also talks fondly of Neil Armstrong, whom he came to know after interviewing him about the 1969 Apollo space mission. That must have been an exciting time? “A worrying time too,”

he adds. “We didn’t know quite what was there. When I heard Neil’s voice saying, ‘The eagle has landed,’ I felt immense relief. There was no provision for things going wrong.” He recalls too the “stand-out moment” when the far side of the moon was first witnessed by William Anders on the Apollo 8 space mission the previous year.

But the world, Sir Patrick says sadly, is no longer what it was. He has always been vocal in his anti-immigration stance and, recently, he has decided the BBC is overrun by women.

“When I started, it was male-dominated, now it is the other way round and that’s equally bad. It presents an unbalanced view.” It’s patently untrue but at 89, it seems unlikely anyone will change his mind. Fortunately, it’s now time for that G&T.

*Miaow! is published by Hubble and Hattie, priced £7.99