her time initially banging stakes into the ground and connecting miles of copper wire. Finally, in July 1967, the array was ready.
Accidental
Jocelyn began the job of monitoring the sky for rapid fluctuations in radio waves that might indicate the presence of a quasar at a particular location. She had to read through literally miles of paper, and wade through mountains of data, searching for tell-tale signs of a quasar. On the 6th August 1967, a few weeks after the array came online, Jocelyn noticed something. She described the discovery that would change her life to this reporter in an interview in 2010: “It was totally accidental. I was doing the research project I had been set very conscientiously and happened across something unexpected. The analogy I use is imagine you are at some nice viewpoint making a video of the sunset and along comes another car and parks in the foreground and it’s got its hazard warning lights, its blinkers on, and it spoils your video. Well my project was looking at quasars, which are some of the most distant things in the universe. [quasars] are big, big things like galaxies, but they are incredibly bright and they send out a lot of radio waves, which is what I was pickin g up. [I was] studying these distant quasars and something in the foreground sort of went ‘yo-hoo’! - not very loudly shall we say it was a pretty faint signal, but it turned out after a lot of checking up, and a lot of persistence to be an incredible kind of new star, which we have called a pulsar pulsating radio star.”
“They are tiny as stars go, they are only about 10 miles across, but they weigh the same as a typical star so they are very, very compact. The radio waves were coming naturally from some kind of star. We picked up these pulses and they were so unexpected that the first thing you have to do is suspect is that there is something wrong with the equipment, then suspect there is interference and then suspect something else, gradually force yourself to believe that it is something astronomical and it’s out there in the galaxy. The excitement came when I found the second one, because that really then begins to look like this is a new population we’ve discovered and we’ve just got the tip of the iceberg.” Inside a few weeks Jocelyn had discovered three more radio wave sources that were behaving in the same way. This proved beyond doubt that here was a new, real and probably entirely natural phenomenon, though there was some talk – only partly in jest – about the possibility that these pulsating radio waves were being sent across the Universe by an alien intelligence. A paper in Nature, the renowned scientific journal followed and it was published on the 24th February 1968. The press interest was huge after the paper came out, and Jocelyn and other people in the lab did a series of newspaper, radio and television interviews. Somehow she managed to get back to finishing her PhD, which she did in September 1968. But her life had changed, and she had become an overnight scientific celebrity, still only in her mid twenties. Jocelyn said that the practical importance of her new found fame was that she never found it difficult to pick
up a job when she was travelling around Britain with her husband, Martin Bell. He was a civil servant that regularly moved from city to city. Jocelyn followed him and worked part time for many years raising their son Gavin, who was born in 1973, and is also a physicist. The down-side of achieving fame and success at an early stage was – as Jocelyn said to this reporter – that people expected her to come up with amazing discoveries all the time. A discovery such as finding pulsars comes only about once per decade in the astronomical community as a whole, and so it is a bit hard, she suggested, to live up to such expectations. These days she continues to work as a Visiting Professor of Astrophysics at Oxford University where she is free to conduct research without too many other duties being imposed on her. Whatever she might do before she retires, her scientific legacy is secure. In 2010, a pulsar conference was held in Sardinia to honour her 45 years in science and to ‘christen’ a new radio telescope. A long-time colleague Australian pulsar researcher, Dick Manchester, was asked to deliver a speech at the conference, detailing Jocelyn’s contribution to science. He said: “I think Jocelyn’s fame is greater because she didn’t receive the Nobel Prize in 1974 than it would have been if she had. I believe that the furore that her lack of recognition caused resulted in a change of attitude by the Nobel Committee and I’m sure more widely as well, with a heightened awareness of the role of students in projects and the role of women in science.”
Snowball Earth
COMPAreD to our more recent ice ages, the great freeze between 600 and 700 million years ago was much more severe. The entire globe is thought to have been covered by ice, and for a long time, scientists wondered how life can have survived this event, known as Snowball earth. Geologist, Dr Dan Le Heron, from the University of London, has questioned the assumption that all parts of the earth were in fact covered. In the Australian Flinders Mountain range of Australia, his team has found evidence to suggest that there were ice-free areas where animals were able to survive until conditions improved and they could repopulate the desolate world.
A boulder, scooped up, and then dropped by melting ice into disturbed sediments that have, over millions of years become solid rock. Evidence, such as this, shows that there must have been violent storms over areas of open sea during a time when most of the globe was frozen over. open sea. Dr Le Heron’s results published in the scientific journal, Geology, are taken as clear evidence to show that extensive areas of ocean remained clear of ice during the Snowball earth era. These clear areas, he said, may well have allowed the life we see around now to survive on Earth.
The evidence is in the form of disturbed sediments, showing a feature known to geologists as hummocky cross bedding. This is a feature that can only be formed by violent storms crossing an
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