Astronomer;

Born: March 4, 1923; Died: December 9, 2012.

Sir Patrick Moore, who has died aged 89, was to space what Sir David Attenborough is to nature: a huge authority on his subject but also a massive television personality with the ability to make a complicated subject popular.

For more than 50 years, Sir Patrick presented The Sky at Night, becoming the longest-serving television presenter of any programme in the world, but he was just as famous for his colourful, eccentric personality: the monocle forever perched on his cheek, his high-pitched, high-speed delivery and his feverish love of the xylophone.

However, at the centre of it all there was always Sir Patrick's skill and passion for astronomy, a passion fired at the age of six when he read a book called Guide To The Solar System, published in 1898. "I picked up that book by sheer luck and sat down by the armchair and read it through," he said. "I understood most of it – which wasn't bad for a six-year-old.".

Patrick Caldwell Moore was born in Middlesex and was educated privately, because of illness. At 11, he was nominated as a member of the British Astronomical Association, becoming the youngest-ever member. He published his first paper, on small craters on the Moon, at the age of 13 – 50 years before he was to be president of the association.

He served with the Royal Air Force from 1940 to 1945, as a navigator in Bomber Command; the girl he was due to marry was killed in an air raid. "My whole life ended in one day," he said. "These things happen. You accept them. As far as I was concerned, that was that. It's the reason I have never married. But I don't like living alone." Nevertheless he did live alone for most of his life at his beloved Selsey in Sussex.

After the war, Sir Patrick's career as an astronomer blossomed. Whereas hardly anybody could name the Astronomer Royal, Sir Patrick became a household name. His years on television began while space travel was "bunk" in the unguarded words of Britain's then Astronomer Royal in 1956. But within six months, Sputnik I was beeping in the heavens. Within three years men were in space and within 12 years they were on the Moon.

As Sir Patrick's popularity as an astronomer, presenting The Sky at Night from 1957, grew, it incurred the jealousy of those who regarded themselves as superior. One Fellow of the Royal Society once said: "We would never elect Patrick Moore as a Fellow, not even for his achievement in science education." Was this, the Fellow was asked, because he had no degree? "No," came the reply, "because he makes science popular."

One of his great triumphs was to explain, on TV, the existence of a giant black hole at the centre of our Milky Way galaxy. Various scientists tried to do it, unsuccessfully, in a variety of weird and wonderful ways. Sir Patrick had a map of the Milky Way drawn on the floor of the studio. He walked towards the centre and then, by some feat of conjuring, disappeared.

One of his more frustrating moments as a broadcaster was recalled when he said: "We'll hear the voices of the first men round the Moon in 20 seconds. This is one of the great moments in human history. And at that moment they switched over to Jackanory."

But he remained loyal to the BBC throughout, even though he had tempting offers from others. "I have no contract with the BBC at all, but I do have a gentleman's agreement, which is totally unbreakable," he once said.

Away from astronomy, he was an accomplished player of the xylophone and composed music for the instrument. He was also a zestful cricketer, who remained a useful and occasionally dangerous medium-pace bowler well beyond his youth.

Sir Patrick was also an ardent fan of Margaret Thatcher, whom he once described as the living woman he most admired, and some of his views attracted criticism. He claimed, for example, to have been bored by anti-South African propaganda.

In 2000, he suffered a paralysis in his right hand which considerably restricted his activities as a musician and a writer. This disability even prevented him from opening the letter telling him he was being considered for a knighthood (he was duly knighted in 2001).

In July 2004, at the age of 81, by his own admission, he nearly died after a severe bout of food poisoning but battled on and in 2007 presented a special 50th anniversary episode of The Sky at Night from his back garden.