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Black hole found eating passing star

Posted at 2:56 PM, Jul 07, 2016
and last updated 2016-07-07 14:56:01-04

A star, caught in the grips of a supermassive black hole.

The immense gravity slowly strips the stellar material from its parent, forming a disc of gas around the black hole as it converts gravitational energy into electromagnetic radiation, producing a bright source of light visible on multiple wavelengths.

Then, even more dramatically, a narrow beam of particles shoots out of the black hole at almost the speed of light.

This galactic phenomenon — known as relativistic jets — was first discovered almost five years ago.

Further clues as to how a black hole feeding on a star produced such outbursts were revealed in March, and now researchers have used an Earth-sized radio telescope network to make record-sharp observations of the phenomenon.

‘Sharpest measurements ever made’

An international team of astronomers, led by Jun Yang at Sweden’s Chalmers University of Technology, used the European VLBI Network (EVN) to study the event known as Swift J1644+57.

First discovered in 2011, Swift J1644+57 is a supermassive black hole slowly swallowing a star. Or rather, was, the galaxy in which the incredible astronomical event is taking place is so far away its light takes 3.9 billion years to reach Earth.

As the ancient star was sucked into the black hole, Yang says it produced jets of light and particles equivalent to the size “of a 2 euro coin on the Moon as seen from Earth.”

“These are some of the sharpest measurements ever made by radio telescopes,” he said in a statement.

Such accuracy was made possible by new technology that uses a network of huge telescopes across our planet, knitting together their observations into an Earth-sized scope that is far more powerful than the sum of its parts.

Next generation telescopes

The team says its findings are likely only the beginning, giving us ever greater insights into one of space’s least understood phenomena.

Earlier this year, gravitational waves created by the merging of two black holes were detected, proving a key part of Albert Einstein’s general theory of relativity, just over 100 years after it was first published.

“Observations with the next generation of radio telescopes will tell us more about what actually happens when a star is eaten by a black hole — and how powerful jets form and evolve right next to black holes,” Stefanie Komossa, astronomer at the Max Planck Institute for Radio Astronomy, said in a statement.

Yang agrees. “In the future, new, giant telescopes like FAST (Five hundred meter Aperture Spherical Telescope) and SKA (Square Kilometer Array) will allow us to make even more detailed observations of these extreme and exciting events.”