The only woman in the world to have named a planet has died at the age of 90.

As an 11-year-old schoolgirl Venetia Phair, a retired teacher from Epsom, suggested the name Pluto for the newly found frozen planet in our solar system.

Former Sutton teacher Venetia Burney, was having breakfast as a child with her grandfather, Falconer Madan, on the morning of March 14, 1930, when he drew her attention to a newspaper report detailing then unnamed planet.

Being keen on Greek and Roman myths, Venetia suggested that Pluto, the Roman god of the underworld, would make a good name for the dark and remote world.

The idea so impressed her grandfather that he put it to his friend Herbert Hall Turner, Professor of Astronomy at Oxford University.

Turner agreed that “Pluto” was an excellent choice for the ice-covered world and forwarded it by telegram to the Lowell Observatory in Arizona.

The astronomers there – including 24-year-old Clyde W Tombaugh, who had made the actual discovery – were delighted with Venetia’s suggestion and on May 1, 1930, the name Pluto was formally adopted.

As a reward for her successful suggestion, Madan gave her a white £5 note – a considerable sum at the time.

Years later she told a newspaper: “I was quite interested in Greek and Roman myths and legends at the time.

“At school, we used to play games in the university park, putting – I think they were lumps of clay – at the right distance from each other to represent the distances of the planets from the Sun.

“Some of the distances I can still more or less remember, so it was probably a good lesson to have had.”

Venetia Katharine Douglas Burney was born on July 11, 1918, the daughter of the Reverend Charles Fox Burney, Oriel Professor of Interpretation of Holy Scripture at Oxford, and his wife, Ethel Wordsworth Madan.

Her father died when she was six, and she went to live with her maternal grandparents in north Oxford.

She was educated at Downe House, and read Mathematics at Newnham College, Cambridge.

During the war she qualified as a chartered accountant, and in the late 1950s switched to teaching economics and maths, first at Gloucester House, Sutton, and later at Wallington County Girls’ School, Surrey, before retiring in the mid-1980s.

Mrs Phair, who died on April 30, married, in 1947, Maxwell Phair, a classicist who became a housemaster and head of English at Epsom College.

He died in 2006, and she is survived by their son Patrick Phair, who now lives in Cheltenham.

In 1987, the asteroid 6235 Burney was named in her honour, as was a student-built instrument on board the New Horizons spacecraft during its mission to Pluto in 2006.

The American space agency Nasa invited her to the launch at Cape Canaveral, but she declined on account of her age.

For the last 25 years, she had been a volunteer with the Friends of Epsom Hospital.

Fellow volunteer Joan Harridge, 80, of Epsom, said: “She was an absolutely amazing woman.

“She would come to work every Thursday come hell or high water.

“She just wanted to do something for the community. She made great friends and we all loved her.”

In 2006, Pluto was officially downgraded from planet to dwarf planet, causing much controversy in astronomy circles.

She was quoted as saying: “It’s interesting that as they come to demote Pluto, so interest in it seems to have grown.”

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