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Times
a day ago
- Science
- Times
Professor Sir Francis Graham-Smith obituary: Trailblazing astronomer royal
While thousands of skygazers stayed awake into the early hours of August 17, 1989, to observe the lunar eclipse, Francis Graham-Smith, the astronomer royal and doyen of British astronomy, was fast asleep. 'I've seen one before, so I didn't sit up into the small hours because it is not as exciting as a total solar eclipse when the sky goes black in the day,' he said. Graham-Smith, a pioneer of radio astronomy, first measured accurate positions of a type of distant galaxies, containing quasars, in the early 1950s. The research he undertook with Sir Martin Ryle, his predecessor as astronomer royal, demonstrated that the universe must have had a definite beginning, demolishing the then-favoured 'steady state' theory of Sir Fred Hoyle and others that the universe had always existed. In the 1970s he contributed to the understanding of pulsars, collapsed stars in which matter is so densely packed that five billion tonnes could be contained in a teaspoon. This was a time when astronomy was booming. 'There were no shortages of positions for young people trying to get into scientific research,' he recalled. By the middle of that decade Graham-Smith was the director of the Royal Observatory Greenwich at Herstmonceux, overseeing the construction of an observatory for British astronomers. 'We didn't have good optical telescopes and we had to go and ask for time on telescopes, mainly in America,' he said. 'I negotiated with Spanish astronomers and the Spanish government that we might build an observatory in the Canary Islands.' To play a better part in the work he learnt to speak Spanish and the resulting Northern Hemisphere Observatory on La Palma is still an important facility for his successors. He went on to be the director of Jodrell Bank Observatory in Cheshire, part of the University of Manchester, and in 1982 was appointed astronomer royal, an office that had been created in 1675 by Charles II, who had a passion for science. 'I didn't have a particular job to do. In fact, by that time it was a purely honorary title,' he said, although he recalled enjoying the state occasions. Despite lacking a formal job description, Graham-Smith was thrust into a debate about astronomy funding after Margaret Thatcher, a scientist by training, decided it was a waste of money after being unimpressed by an over-ambitious live 1986 BBC programme in which he appeared — it was about the European spacecraft Giotto passing through the tail of Halley's comet. 'We have no shortage of excellent students, but they will probably work abroad,' he protested. 'The fact that we will go on populating the world with British astronomers is absolutely splendid, but wouldn't it be nicer to think that just a few would stay at home?' Indeed, Graham-Smith was a great champion of young people in astronomy. 'You can go and look at telescopes, you can go and look through telescopes, you can visit Jodrell Bank, you can read … But the main thing is to introduce school children to astronomy and make it look interesting, fascinating. Which it is,' he said. Rather than indulge in astrology, which he dismissed as a 'ridiculous piece of humbug', he suggested that every child be offered the opportunity to stare into space, adding: 'Like Gerard Manley Hopkins, I should direct them to the real thing. 'Look at the stars! Look up at the skies!'' Francis Graham Smith was born in Roehampton, Surrey, in 1923, the younger of two sons of Claud Smith, a civil servant and hospital administrator, and his wife Cicely (née Kingston); his brother, Derek, a civil nuclear engineer, predeceased him. He was known as Graham but started using Francis in adulthood; similarly, he only adopted the hyphenation after being knighted in 1986, changing his name by deed poll to Graham-Smith. He was educated at Epsom College, Surrey, and Rossall School, Lancashire, before reading physics at Downing College, Cambridge, where his course included a section on electronics and radio. He arrived with conventional beliefs about heavenly bodies, which were discarded 'when I started to think seriously about them', and was later a patron of Humanists UK. His studies were interrupted by service with the Home Guard in Blackpool and work on radar for the Telecommunications Research Establishment at Malvern. Immediately after VE Day he was sent to Bombay, spending six months as part of a support group for the war in the east. 'VJ day came soon after I arrived, so there was nothing much to do,' he recalled. Nevertheless, his wartime experience proved invaluable. 'At the end of the war we went back to our universities and developed the subject of radio astronomy, which was really quite new,' he told Science Café on BBC Wales in 2023. His PhD studies involved research with Ryle at the Cavendish Laboratory, Cambridge, but there was little money and their radio telescopes were either homemade or requisitioned war items. Their early work involved examining radio waves from the outer parts of the sun. 'Then we discovered that among the signals which had been detected before from the Milky Way, there were individual spots,' he said. In 1949 he and Ryle used a pair of Würzburg radio telescopes to make accurate position measurements of Cygnus A and Cassiopeia A, the two brightest radio sources in the sky. These enabled the former to be associated with a distant galaxy and the latter with a supernova explosion that took place about 250 years earlier. 'I had the good luck to be the first to observe that and to measure its position,' he said. Another Cavendish researcher was Dorothy Palmer, known by her middle name Elizabeth. They were married in 1945 and she became a maths teacher, potter and tai-chi expert, writing fitness books for the over-fifties. Keeping radio astronomy in the family Elizabeth's sister, Rowena, and Ryle married in 1947. Gradually Graham-Smith's attention turned from radio waves to astronomy, though with no experience of finding his way around the sky he had to learn the basics by lying on his back on a starlit night. 'I was always interested in radios and so physics seemed the path to follow. But during my research into radio science it became clear that what we were actually doing was astronomy,' he said. He soon became one of the leading figures in the field, publishing scientific papers and his first book, Radio Astronomy (1960, with JH Thomson). In 1964 he was appointed professor of radio astronomy at the University of Manchester under Sir Bernard Lovell (obituary, August 8, 2012), the founder of Jodrell Bank. A decade later he moved to Greenwich, his tenure coinciding with both the observatory's tercentenary in 1975 and his presidency of the Royal Astronomical Society from 1975 to 1977. In 1981 he returned to Manchester, succeeding Lovell at Jodrell Bank where he helped to develop a visitor centre. For many years Graham-Smith lived in Henbury, Cheshire, where he was among the founders of the village's Millennium Green. Home was the Old School House, an eccentric series of adaptable open spaces with a large, galleried lounge linked to other parts of the complex through an extension built by the astronomer royal himself. The family also had a cottage in the hills behind Caernarfon in north Wales, from where they enjoyed walking and sailing. Elizabeth died in 2021 and Graham-Smith is survived by their three sons: David, a geologist; Andrew, an engineer; and Piers who studied crystallography; and by their daughter, Helen, an artist. A favourite activity for the children when they were young was climbing inside the giant bowl of the Jodrell Bank radio telescope and rolling pennies around inside it. Some years later slots were added to the bowl, meaning future coin-rollers' pennies fell to the ground. Graham-Smith retired in 1990, the same year he lent his name to a campaign for darker skies. He remained active in his own field and in the wider academic world, serving as pro vice-chancellor of the University of Manchester and as physical secretary of the Royal Society. He continued to publish into his nineties. Among his later works is Eyes on the Sky (2016), a remarkable exploration of how technology can give an in-depth picture of the nature of the universe. At its core is the message to keep looking up: you just never know what you might discover. For someone whose eyes were fixed on the stars, Graham-Smith was a down-to-earth character, passionate about bricklaying, furniture-making and tending to his bees. His other interests included the music of Shostakovich and the biography of Primo Levi. The secret to a long life, he said, was 'keeping busy'. He never lost his schoolboy-like enthusiasm and in 1986 was seen giving Anneka Rice a piggy-back in an episode of Channel 4's Treasure Hunt, which was filmed at Jodrell Bank and which his family dug out for his 100th birthday celebrations. 'I've always been interested in publicity, particularly for educational activities,' he said. Although a radio astronomer, Graham-Smith specialised in studying stars that could not be seen by the naked eye. He claimed to know so little about visible stars that he would never be able to find his way home by them. 'I certainly couldn't navigate my dinghy by the stars,' he said. As for getting physically closer to them, he was having none of it. 'Space travel is far too dangerous,' he added. 'Stars are like fireworks. You stand clear and study them from afar.' Professor Sir Francis Graham-Smith FRS, astronomer royal 1982-90, was born on April 25, 1923. He died on June 20, 2025, aged 102
Yahoo
15-06-2025
- Science
- Yahoo
Astronomers discover ultrapowerful black hole jet as bright as 10 trillion suns lit by Big Bang's afterglow
When you buy through links on our articles, Future and its syndication partners may earn a commission. Astronomers have discovered extraordinarily powerful X-ray jets blasting from two supermassive black holes that are so ancient that the jets shine in the afterglow of the Big Bang. "They are transforming the first light of the universe into high-energy jets," Jaya Maithil, a postdoctoral research fellow at the Harvard and Smithsonian Center for Astrophysics, told reporters Monday (June 9) at the 246th meeting of the American Astronomical Society in Anchorage, Alaska. Using data from NASA's Chandra X-Ray Observatory and the Karl G. Jansky Very Large Array (VLA), Maithil and her team found that each jet spans a whopping 300,000 light-years — nearly three times the diameter of our Milky Way galaxy. Each jet emerges from an actively feeding supermassive black hole, known as a quasar, located about 11.6 billion and 11.7 billion light-years away. The researchers observed these immense structures as they appeared when the universe was just 3 billion years old, during a period when galaxies and their central black holes were growing at breakneck speed. "These quasars are like cosmic time capsules," Maithil said. "If we understand them, we can understand how they were impacting the growth of their galaxy and the environment in which they resided." One of the newfound jets, from a quasar known as J1610+1811, is visible in the Chandra image above. A slender, faint purple line extends from the quasar's brilliant white core toward the upper right, ending in a small, bright blob. A second, dimmer jet appears to shoot in the opposite direction, downward and to the left. "It's like looking for candlelight in close vicinity to a flashlight that's blazing toward us," Maithil said. Related: Hungry black hole shoots out bright X-ray jet 60,000 times hotter than the sun What makes these jets particularly noteworthy is that they remain visible across billions of light-years. In a paper accepted for publication in The Astrophysical Journal, Maithil and her team suggested that the jets shine in X-rays thanks to interactions with the cosmic microwave background (CMB) — the faint relic radiation from the Big Bang left over after the universe cooled enough for starlight to travel freely for the first time, marking the end of the "cosmic dark ages." Back when these jets formed, the CMB was far denser than it is today, filling space with a sea of low-energy photons. As electrons in the jets raced outward at near light speed, they slammed into these CMB photons, boosting them into the X-ray range detectable by Chandra, according to the new study. RELATED STORIES —Brightest quasar ever seen is powered by black hole that eats a 'sun a day' —How black-hole-powered quasars killed off neighboring galaxies in the early universe —Distant 'quasar tsunamis' are ripping their own galaxies apart This process makes them visible across cosmic gulfs, despite their proximity to the quasars' dazzling cores, the researchers said. The jet from J1610+1811 clocks in at 92% to 98% light, carrying about half as much energy as all the light emitted by matter spiraling into the black hole — a staggering output equivalent to that from 10 trillion suns, the new study found. The second quasar, J1405+0415, located 11.7 billion light-years from Earth, features a jet just as powerful. By combining Chandra's X-ray and VLA's radio data, the researchers calculated that particles in the J1405+0415 jet are traveling at 95% to 99% the speed of light. "We're finding that some black holes may carry a bigger punch at this stage in the universe than we thought," Maithil said in a statement.
