She was 14 years old, a young Lurgan girl with an enquiring mind and a voracious appetite for books. Her dad, she describes as widely read - he'd been the Ulster finalist in the Brains of Britain competition on BBC radio - and when he brought home library books, which he did regularly, Jocelyn was always keen to peruse them too.
That evening he'd brought home a few tomes on astronomy - not such an unusual choice after all for Philip Bell, the architect who helped design the Armagh Planetarium.
"I looked at them and I thought, 'that's for me'," recalls Dame Jocelyn Bell Burnell. "I removed them to my bedroom."
And so began a love affair with astrophysics which was to culminate in what has been described as "one of the most significant scientific achievements of the 20th century".
In 1967, Dame Jocelyn ("Just call me Jocelyn") discovered radio pulsars - a breakthrough for which her male supervisor, but not she, was, highly controversially, to be awarded a Nobel prize for physics.
A pulsar (the word is a contraction of pulsating star) is described as highly magnetised rotating neutron star or 'white dwarf' and Dame Jocelyn, who featured in the BBC documentary series Beautiful Minds, made her first discovery on November 28, 1967.
She and her thesis supervisor Antony Hewish (she was a PhD research student at the time) did not, she later explained, "really believe that we had picked up signals from another civilisation, but obviously the idea had crossed our minds and we had no proof that it was an entirely natural radio emission.
"It is an interesting problem - if one thinks one may have detected life elsewhere in the universe, how does one announce the results responsibly?"
The pulsar was initially dubbed LGM-1, the initials standing for Little Green Men (Who says scientists don't have a sense of humour?).
In the television documentary she described how on a perishing cold December at around 2am/3am she had switched on the high speed camera and recorded another: "Blip, blip, blip."
That she said, was "sweet".
It finally scotched the 'little green men' hypothesis, she added, since it was "highly unlikely there were two groups of little green men at opposite ends of the universe, both deciding to signal to a rather inconspicuous Planet Earth using a daft technique and a commonplace frequency..."
Dame Jocelyn had helped build the radio telescope that made the initial and later discoveries. At first Hewish believed the anomaly she had spotted was man-made interference and she had to convince him that it was something more.
Yet the subsequent paper announcing the discovery of pulsars listed Hewish's name first (her's second) and won for him and the astronomer Martin Ryle the Nobel Prize.
Dame Jocelyn was not cited as a co-recipient of the prestigious prize - an exclusion that still remains deeply controversial with many believing it was down to sexism, pure and simple. She herself, however, is surprisingly magnanimous. Her response, in the gentle Co Armagh accent she still retains, is the equivalent of putting a telescope lens up to a glass ceiling - and looking right through it.
In a previous interview she noted that "demarcation disputes between supervisor and student are always difficult, probably impossible to resolve... it is the supervisor who has the final responsibility for the success or failure of the project".
She added: "We hear of cases where a supervisor blames his student for a failure, but we know that it is largely the fault of the supervisor. It seems only fair to me that he should benefit from the successes too.
"I believe it would demean Nobel Prizes if they were awarded to research students, except in very exceptional cases, and I do not believe this is one of them.
"Finally," she noted in a cheery aside. "I am not myself upset about it - after all, I am in good company, am I not?"
Back in Northern Ireland last week for a series of events to mark the 50th anniversary of the planetarium her father designed, she reiterates that same remarkable lack of rancour.
She's an immensely likeable, quick-witted woman who repeatedly uses the word "fun".
Of the Nobel award she says: "Politically it was very important as there was, there is no Nobel Prize for astronomy, no Nobel Prize for mathematics."
(The prizes which Alfred Nobel had designated in his will were for physics, chemistry, physiology or medicine, literature and peace).
"This was the first time ever then, that the physics prize had gone to astronomy. It convinced the physicists that there was good physics in astronomy.
"So did I feel cheated? No."
Besides, she adds: "I know from another pulsar astronomer who won the Nobel that you get no peace. You're asked about every subject under the sun. It quite wrecks your life."
She says this laughingly.
And if you do win a Nobel she adds, you don't win anything else because nothing can top it. But if you don't win, then you are open to many other honours and awards "with parties where you have much more fun".
Born in 1943, she was educated originally at the Lurgan College Preparatory Department. She failed her 11-plus and went on to a Quaker boarding school in York in England.
At school in Lurgan she, along with all the other girls, had been expected to do needlework and cooking instead of science. Parents protested and the system was changed. In York her interest in - and flair for - physics grew, encouraged by her "really good" physics teacher, Mr Tillott.
She went on to study physics at Glasgow University before getting her PhD from Cambridge. She is a former President of the Royal Astronomical Association and of the Institute of Physics.
She feels that encouraging interest in science subjects, particularly among girls, needs to involve their families and society at large.
"We need particularly to address their parents. There's a view among some parents perhaps that there's more money to be had in other careers," she says.
"I think in terms of getting younger people interested, Professor Brian Cox is helping change all that."
But, she also notes: "Britain has still got rather fewer astronomers than many other countries. The French and the Italians, for example. Why is that? I don't think those countries have better brains."
Her own mother took a keen interest in her daughter's spectacular achievements - she kept a scrapbook of newspaper cuttings which have now been passed on to Dame Jocelyn herself.
Divorced from her husband Martin Burnell in the 1990s, they have one son who is called Gavin. Her brother Adrian and sister-in-law Maeve joined her last week at the planetarium for the celebration which included music by the Ulster Orchestra.
One of Dame Jocelyn's contemporaries at Cambridge was the late Stephen Hawking. When I point out that Hawking, unlike herself, was a famous non-believer (she remains a committed Quaker) she points out in turn: "That's just one person."
Lots of academics and scientists like herself are also religious, she says.
Meanwhile, Dame Jocelyn Bell Burnell's fascination with the mysteries of the universe extends to her down time.
For relaxation she very much enjoys poetry - "poetry with an astronomical field" that is.
She was delighted that the Ulster Orchestra had agreed to take part in last week's anniversary events at the Armagh Planetarium, as an accompaniment to her presentation.
The planetarium which cost £120,000 to build, was opened in May 1968 following years of campaigning by Dr Eric Lindsay.
The building was extended in 1974 to incorporate the Lindsay Hall which bears his name and was refurbished in 2006.
Among the audience at the 50th anniversary celebrations have been political party leaders, government and council representatives and industry experts including visitors from the European Space Agency.