Tag Archives: black hole

Black hole discoveries win 2020 Nobel Prize in Physics

By Niklas Pollard and Douglas Busvine

STOCKHOLM/BERLIN (Reuters) – Britain’s Roger Penrose, Reinhard Genzel of Germany and American Andrea Ghez won the 2020 Nobel Prize for Physics on Tuesday for their discoveries about one of the most exotic phenomena in the universe, the black hole.

Penrose, professor at the University of Oxford, won half the prize of 10 million Swedish crowns ($1.1 million) for his work using mathematics to prove that black holes are a direct consequence of Albert Einstein’s general theory of relativity.

Genzel, of the Max Planck Institute and University of California, Berkeley, and Ghez, at the University of California, Los Angeles, shared the other half for discovering that an invisible and extremely heavy object governs the orbits of stars at the center of our galaxy.

Ghez – only the fourth woman to be awarded the Physics prize after Marie Curie in 1903, Maria Goeppert-Mayer in 1963 and Donna Strickland in 2018 – said she hoped it would inspire others.

Asked about the discovery of a massive yet invisible object at the heart of the Milky Way, Ghez said “the first thing is doubt”.

“You have to prove to yourself that what you are really seeing is what you think you are seeing. So, both doubt and excitement,” the 55-year-old astronomer said in a call with the committee after receiving the award.

“It’s that feeling of being at the frontier of research when you have to always question what you are seeing.”

Genzel, 68, told Reuters Television soon after hearing he had shared the prize that had been on a Zoom call with colleagues when the phone rang.

“Just like in the movies, a voice said: ‘This is Stockholm’,” he said. He admitted to being flabbergasted by the news: “I cried a little bit.”

WHERE TIME ENDS

Scientists have wondered since the 18th century whether any object existed in the universe that would exert a gravitational pull so strong that light may not be able to escape.

Einstein predicted in 1915, in his general theory of relativity, that space and time could be warped by the force of gravity. Yet he did not actually believe in black holes, and finding a way to prove their existence baffled scientists for another 50 years.

“It was a theory – there was nothing to make black holes visible,” said Genzel.

It was not until a seminal paper in 1965 that Penrose, now 89, proved that black holes can really form – describing them in detail and stating that, at their center, time and space cease to exist.

Illustrating Penrose’s insight at the awards presentation in Stockholm, Ulf Danielsson of the Nobel Committee held a black ball the size of a grapefruit in one hand and pointed at it with the finger of his other hand.

At the ball’s edge, time stands still, Danielsson said, and as his finger pushed into it, its tip moves into the future.

It would be impossible to withdraw one’s finger without tearing it apart. Instead it would be “carried all the way into the center of the black hole, where time ends and the known laws of physics cease to apply”.

‘AWE-INSPIRING’ MYSTERY

Subsequent efforts to find a black hole focused on the clouds of dust in a region of the Milky Way called Sagittarius A*. By observing movements of stars, teams of astronomers led by Genzel and Ghez concluded that around 4 million solar masses are packed into a region the size of our solar system.

“Penrose, Genzel and Ghez together showed us that black holes are awe-inspiring, mathematically sublime, and actually exist,” said Tom McLeish, professor of natural philosophy at Britain’s University of York.

While black holes are now accepted science, much about them remains a mystery.

“What is the black hole? We don’t know, we have no idea what is inside a black hole and that is what makes these things such exotic objects,” said Ghez.

Physics is the second of this year’s crop of Nobels to be awarded, after three scientists won the medicine prize for their discovery of Hepatitis C on Monday.

The Nobel prizes were created in the will of Swedish dynamite inventor and businessman Alfred Nobel and have been awarded since 1901.

This year’s awards are taking place under the long shadow of the COVID-19 pandemic that has curtailed much of the usual festivities surrounding the prizes. ($1 = 8.9108 Swedish crowns)

(Reporting by Niklas Pollard and Douglas Busvine; Additional reporting by Johannes Hellstrom, Supantha Mukherjee, Simon Johnson, Colm Fulton and Anna Ringstrom; Editing by Alex Richardson)

Caught in the act: a black hole rips apart an unfortunate star

After passing too close to a supermassive black hole, a star is torn apart into a thin stream of gas, which is then pulled back around the black hole and slams into itself, creating a bright shock and ejecting more hot material, in this artist's conception released on September 26, 2019. Illustration by Robin Dienel/Courtesy of the Carnegie Institution for Science/Handout via REUTERS

By Joey Routlette

WASHINGTON (Reuters) – Scientists have captured a view of a colossal black hole violently ripping apart a doomed star, illustrating an extraordinary and chaotic cosmic event from beginning to end for the first time using NASA’s planet-hunting telescope.

The U.S. space agency’s orbiting Transiting Exoplanet Survey Satellite, better known as TESS, revealed the detailed timeline of a star 375 million light-years away warping and spiraling into the unrelenting gravitational pull of a supermassive black hole, researchers said on Thursday.

The star, roughly the same size as our sun, was eventually sucked into oblivion in a rare cosmic occurrence that astronomers call a tidal disruption event, they added.

Astronomers used an international network of telescopes to detect the phenomenon before turning to TESS, whose permanent viewing zones designed to hunt distant planets caught the beginning of the violent event, proving effective its unique method of surveilling the cosmos.

“This was really a combination of both being good and being lucky, and sometimes that’s what you need to push the science forward,” said astronomer Thomas Holoien of the Carnegie Institution for Science, who led the research published in the Astrophysical Journal.

Such phenomena happen when a star ventures too close to a supermassive black hole, objects that reside at the center of most large galaxies including our Milky Way. The black hole’s tremendous gravitational forces tear the star to shreds, with some of its material tossed into space and the rest plunging into the black hole, forming a disk of hot, bright gas as it is swallowed.

“Specifically, we are able to measure the rate at which it gets brighter after it starts brightening, and we also observed a drop in its temperature and brightness that is unique,” Holoien said.

Observing the oscillation of light as the black hole gobbles the star and spews stellar material in an outward spiral could help astronomers understand the black hole’s behavior, a scientific mystery since physicist Albert Einstein’s work more than a century ago examined gravity’s influence on light in motion.

(Reporting by Joey Roulette; Editing by Will Dunham)

Scientists confirm Einstein’s supermassive black hole theory

Communication Lab in Kiel Germany, released on July 12, 2018. Courtesy DESY, Science Communication Lab/Handout via REUTERS

BERLIN (Reuters) – A team of international scientists observing a star in the Milky Way have for the first time confirmed Einstein’s predictions of what happens to the motion of a star passing close to a supermassive black hole.

Einstein’s 100-year-old general theory of relativity predicted that light from stars would be stretched to longer wavelengths by the extreme gravitational field of a black hole, and the star would appear redder, an effect known as gravitational redshift.

“This was the first time we could test directly Einstein’s theory of general relativity near a supermassive black hole,” Frank Eisenhauer, senior astronomer at the Max Planck Institute for Extraterrestrial Physics, told journalists.

“At the time of Einstein, he could not think or dream of what we are showing today,” he said.

A team of scientists at the European Southern Observatory started monitoring the central area of the Milky Way using its Very Large Telescope to observe the motion of stars near the supermassive black hole 26 years ago.

The black hole is 26,000 light years away from Earth and has a mass 4 million times that of the Sun.

The scientists selected one star, S2, to follow. With an orbit of 16 years, they knew it would return close to the black hole in 2018.

Over 20 years, the accuracy of their instruments has improved and so in May 2018, they were able to take extremely precise measurements in conjunction with scientists from around the world.

This showed the star’s orbital velocity increasing to more than 25 million kph (15.5 million mph) as it approached the black hole.

The star’s wavelength stretched as it sought to escape the gravitational pull of the supermassive black hole, shifting its appearance from blue to red, Odele Straub from the Paris Observatory said.

The scientists now hope to observe other theories of black hole physics, she said.

“This is the first step on a long road that the team has done over many years and which we hope to continue in the next years,” MPE’s Reinhard Genzel, who led the international team, said.

(Reporting by Victoria Bryan, editing by David Evans)