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Antony Hewish, a pioneer of radio astronomy, who discovered a surprising class of stars known as pulsars, for which he won the Nobel Prize, died Monday. He was 97 years old.
His death announced by Cambridge University in England, where he taught for many years. The announcement did not say where he died.
Pulsars, or pulsating radio stars, are embers of massive stars that explode as supernovae. Dr. Hewish built a radio telescope with the right features for detecting rapidly changing radio waves—the signature emission of pulsars—although it was designed for other purposes.
he shared 1974 Nobel Prize in Physics with another radio astronomer, Martin Ryle, his longtime friend and Cambridge colleague. However, the Nobel committee’s Dr. Hewish was criticized for citing his “decisive role in the discovery of pulsars.” astronomer Fred Hoyle signals from the first two pulsars are actually Spotted and analyzed by Jocelyn Bell, a 24-year-old Cambridge graduate student working on the new telescope. Dr. Hewish was his advisor and doctoral dissertation advisor.
Dr. His finding was kept secret for six months, Hoyle wrote in a letter to The Times of London, “while his superiors were “heavyly busy seizing the girl’s discovery, or that’s what it meant”.
Other astronomers noted that Ms. Bell’s assigned task was to plan for glowing radio sources, but she noticed and followed a different type of signal.
Dr. Hewish in 1975. “Jocelyn was a very nice girl, but she was just doing her job,” she told an interviewer for Science magazine after Hoyle’s criticisms went public. “He realized that this source was doing this thing. If he hadn’t noticed, he would have been negligent.”
Antony Hewish was born on May 11, 1924, in the small seaside town of Fowey in Cornwall, England. His father was a banker. He began studying science at Cambridge in 1942, but after World War II.
The team leader, Dr. John, who began a distinguished career in developing radio astronomy at Cambridge after the end of the war. It was Ryle. Dr. He joined the Hewish group and Dr. He became interested in determining which of the thousands of radio-emitting galaxies Ryle had discovered were quasars.
Quasars, now known as supermassive black holes, were then considered point sources of radio waves, as opposed to large sources like radio galaxies. The radio signals of quasars vibrate with intensity as they pass through the solar wind. Dr. Hewish designed a special type of radio telescope to detect these flashes, which was completed in 1967.
He set Ms. Bell to scan the recordings produced by her telescope and to distinguish real stellar flares from artificial sources of interference, such as pirate radio stations or aircraft altimeters.
The telescope produced paper charts of about 400 feet for each full coverage of the sky. In October 1967, Mrs. Bell noticed a half-inch gap that looked neither man-made nor stellar. He remembered seeing a sign with the same shape on a recording almost 24 hours ago. Further analysis showed that the bumps consisted of highly regular pulses spaced for a little over a second.
The extreme regularity of the pulses indicated some sort of fabricated source. However, Dr. Hewish later determined that the source appeared every 56 minutes, not every 24 hours, but every 23 hours. It was keeping up with the rotation of the stars, not the Earth, and so it must have been extraterrestrial.
Astronomers realize that if there is intelligent life beyond Earth, they will likely be the first to know. With its precisely timed signal, this asterisk was so unexpected that no explanation could be ruled out, including the possibility of an intentional signal.
Only partly as a joke, the source was nicknamed LGM-1 for “little green men.” Dr. Hewish later said in an interview He said he believed, over a two-month period, “it’s possible that the signal may have come from aliens.”
While the elders were debating how they could publish the discovery without any idea of what it was, Ms. Bell came to a decisive finding. He detected a second such source, which emits regular pulses but at a different speed. It seemed unlikely that the two extraterrestrial groups would be sending signals to Earth at different frequencies, so the source was more likely to be a new type of star.
Dr. Hewish confirmed that nothing happened. doppler shift in the signal, as would be expected if the source were on a planet orbiting the sun. (Doppler shift is the phenomenon that, for example, causes a train whistle to appear to change in frequency as it passes by an observer.)
The discovery of pulsars, kept a closely guarded secret by the Cambridge radio astronomy group, Published in the journal Nature February 24, 1968 According to Scientific rule, when a student discovers that a professor’s intellect and tools are possible, the student’s name is written first on the authorship line and at the end of the professor, along with other assistants.
Had this convention followed, Ms. Bell and Dr. Hewish would be presented as co-explorers of extraordinary new stars. However, as the first author of the journal Nature, Dr. Hewish was followed by Mrs. Bell, who made a few minor contributors. Convincing for the Nobel committee, the result was Dr. Hewish was the only discoverer. (Dr. Ryle, who shared that year’s NobelHe is credited with developing the revolutionary radio telescopes that paved the way for the discovery of pulsars.)
Unlike the Nobel committee, the Franklin Institute of Philadelphia was honored in 1973 by Ms. Bell and Dr. Hewish jointly awarded an award. This decision was followed by many other explanations. In 2018, Ms. Bell was named at the time Dr. Bell Burnell was awarded the $3 million prize. Breakthrough Award In Fundamental Physics for his work on pulsars. (The foundation that sponsors the award was founded by Google co-founder Sergey Brin and Facebook co-founder Mark Zuckerberg, among others.)
Hewish was professor of radio astronomy at the Cavendish Laboratory in Cambridge from 1971 to 1989 and Dr. He was president of the Mullard Radio Astronomy Observatory near Cambridge, founded by Ryle.
Among the survivors is his wife, Marjorie, whom he married in 1950.
Mathew Brownstein contributed to the reporting.
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