Astronomers spot star dancing around black hole according to Einstein's theory

Astronomers in Chile using one of the world's largest telescopes have found a star "dancing" around a black hole in the Milky Way just as Albert Einstein might have predicted more than a century ago.

30 years of measurements reveal rosette-shaped orbit around supermassive black hole

Observations made with ESO’s Very Large Telescope (VLT) have revealed for the first time that a star orbiting the supermassive black hole at the centre of the Milky Way moves just as predicted by Einstein’s theory of general relativity. Its orbit is shaped like a rosette and not like an ellipse as predicted by Newton's theory of gravity. This effect, known as Schwarzschild precession, had never before been measured for a star around a supermassive black hole. This artist’s impression illustrates the precession of the star’s orbit, with the effect exaggerated for easier visualisation. (L. Calçada/ESO)

Astronomers in Chile using one of the world's largest telescopes have found a star "dancing" around a black hole in the Milky Way just as Albert Einstein might have predicted more than a century ago.

Einstein's General Theory of Relativity, published in 1915, is a foundation of modern physics. It has long helped scientists understand the forces of gravity.

But Thursday's announcement from the European Southern Observatory (ESO), an intergovernmental group of European astronomers that operates in Chile, proves the theory applies even to a star some 26,000 light years from the Sun.

This visible light wide-field view shows the rich star clouds in the constellation of Sagittarius (the Archer) in the direction of the centre of our Milky Way galaxy. The entire image is filled with vast numbers of stars — but far more remain hidden behind clouds of dust and are only revealed in infrared images. This view was created from photographs in red and blue light and forming part of the Digitized Sky Survey 2. The field of view is approximately 3.5 degrees x 3.6 degrees. (ESO and Digitized Sky Survey 2)

Nearly 30 years of measurements, ESO scientists said in a statement, allowed them to follow the star as it traced a rosette-shaped orbit around the "supermassive" black hole in the Milky Way. Their discovery proved Einstein, and not his predecessor Isaac Newton, was right. Newton believed it would travel in an ellipse-like pattern.

"This long-sought-after result was made possible by increasingly precise measurements over nearly 30 years, which have enabled scientists to unlock the mysteries of the behemoth lurking at the heart of our galaxy," the observatory said in a statement.

WATCH | Star dances around a black hole

Star dances around a black hole

1 year ago
Rosette-shaped orbit predicted by Einstein's theory of general relativity 1:37

More evidence of black hole's existence

The discovery also provides further evidence of the existence of a black hole called Sagittarius A*, which is believed to have 4 million times the mass of the Sun, the statement said.

This simulation shows the orbits of stars very close to the supermassive black hole at the heart of the Milky Way. (ESO/L. Calçada/

The ESO's Very Large Telescope, pivotal in the finding, sits atop a mountain at nearly 2,700 metres in Chile's vast and sparsely populated Atacama desert.

The region's low humidity and smooth airflow create unrivaled visibility for the high-tech telescopes that scientists use to shed light on the formation of the universe and the possibility of extraterrestrial life.

In the past 30 years, Chile has carved out a niche as the global hub for observational astronomy.


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