Family and friends gathered to bid a poignant farewell to a “seemingly straightforward man” who was one of the leading science journalists of his age.

It was with both great joy and great sadness that Dr Tom Margerison’s family said a final goodbye last Thursday to the man they movingly described as “our encyclopaedia of life”.

During a service at Highgate’s United Reformed Church, which was filled with poetry and music, they remembered “an inspirational father and a great man”.

Dr Margerison had been at the top of his profession. He came to prominence as the co-founder of the New Scientist magazine and was the voice of science on the BBC’s Tonight programme and science editor of The Sunday Times.

He was later involved in the bid for London Weekend Television and took over as managing director before the involvement of Rupert Murdoch as an investor led to Dr Margerison’s departure in 1971, when he magnanimously said: “You cannot have two people running a ship.”

Starting in the late 1990s, Dr Margerison faced the last great challenge of his life, a 15-year battle with Parkinson’s disease.

Not even this cruel and crippling illness diminished his enduring love for his partner of 40 years, the journalist and campaigner Marjorie Wallace, as was remembered eloquently in eulogies by her sons Sacha and Stefan Skarbek, 41 and 38.

Tom was, Sacha said, “a man of strong passion and huge heart” and “it was with this passion that Tom loved my mother, who remained his marvellous star”.

“I passionately believe he fought his disease and age with dogged determination that they would stay together,” he said.

Sacha, a successful songwriter whose hits include James Blunt’s You’re Beautiful, also spoke of Dr Margerison’s “extraordinary influence and achievement” as he quoted the late Sir David Frost, who said of him: “I loved his brains, brains in the plural.”

Particularly noted was Dr Margerison’s ability to explain complex scientific matters in a way that people could relate to – with just such pithy wordplay he once portrayed the moon as a “cosmic snowball”.

Also reading at the funeral service was actor Tom Conti, who attended with wife Kara Wilson, and in the congregation were author and former MEP Stanley Johnson, Kinks frontman Ray Davies, and the journalist and writer Valerie Grove.

White lilies and roses sat among purple and yellow floral bouquets decorating the church and a five-voice choir sang Bach and Mozart, as well as Cole Porter’s True Love and Rodgers and Hammerstein’s Hello, Young Lovers, a tribute to Marjorie and Tom’s shared passion for musical show tunes.

Later, champagne toasts were led at the family home in Bisham Gardens by Mr Johnson, Marjorie and the couple’s daughter Sophia, 30, said to be her father’s “beloved angel child”.

During one of the most moving parts of the church service, Marjorie, who founded the mental health charity SANE after a successful career as an investigative writer and journalist, read a poem, The Final Port, that she had composed for Tom after taking him in his wheelchair to a performance of High Society at the Open Air Theatre.

In it, she said: “I will tie red ribbons to the deck,

“Of your departing yacht,

“And all will see your sails unfurled,

“But none the final port.”

In her eulogy, she added: “Tom was simply the most brilliant man I have ever met, and I’ve met quite a few in my rather colourful career.

“Being with Tom was like being plugged into a light socket and, during those moments of profound love, it was like the world lit up for both of us.”

Dr Margerison died on February 25, aged 90.