One of the key predictions of Albert Einstein has passed a rigorous observation test. Thanks to the ESO's Very Large Telescope, researchers were able to track a star through the extreme gravitational field near a supermassive black hole and confirmed that the star behaves as predicted by Einstein's general theory of relativity.
Einstein proposed general theory before the theory of relativity predicted in 1915 and predicted that the light coming from a star would be stretched to longer wavelengths due to the extreme gravitational field of a black hole. As a result, the light shifts to the red end of the spectrum. This effect is called a gravitational redshift. So far, there has been no precise test of this theory on astronomical scales.
"This was the first time that we could test Einstein's General Theory of Relativity directly on a supermassive black hole." Frank Eisenhauer, astronomer at the Max Planck Institute said in a statement.
To test the idea, researchers observed supermassive black hole in the center of the Milky Way. The black hole is 26 000 light-years from Earth and is surrounded by a small group of stars orbiting at high speed. This extreme environment is a perfect place to explore gravitational physics and test Einstein's general theory of relativity.
Using telescopes at the European Southern Observatory in Chile, researchers specifically observed the motion of a star near the supermassive black hole for more than 20 years. The star, called S2, passed very near the Black Hole in May 201
The event delivered extremely accurate measurements that astronomers needed to test Einstein's theory. The new measurements clearly showed the effects predicted by the famous theory.
"This is the second time that we have observed the close passage of S2 around the black hole in our galactic center, but this time we were able to observe the star with unprecedented resolution thanks to much better instrumentation," said Research Director Reinhard Genzel from the Max Planck Institute for Extraterrestrial Physics "We have been intensively prepared for this event over several years. We wanted to use this unique opportunity to observe general relativistic effects."