Artist’s impression of S2 passing supermassive black hole at centre of Milky Way. Image credit: ESO/M. Kornmesser
Observations made with the European Southern Observatory’s (ESO) Very Large Telescope (VLT) have for the first time revealed the effects predicted by Einstein’s general relativity on the motion of a star passing through the extreme gravitational field near the supermassive black hole in the centre of the Milky Way. This long-sought result represents the climax of a 26-year-long observation campaign using ESO’s telescopes in Chile.
Obscured by thick clouds of absorbing dust, the closest supermassive black hole to the Earth lies 26 000 light-years away at the centre of the Milky Way. This gravitational monster, which has a mass four million times that of the Sun, is surrounded by a small group of stars orbiting around it at high speed. This extreme environment — the strongest gravitational field in our galaxy — makes it the perfect place to explore gravitational physics, and particularly to test Einstein’s general theory of relativity.
New infrared observations from the exquisitely sensitive GRAVITY, SINFONI and NACO instruments on the VLT have now allowed astronomers to follow one of these stars, called S2, as it passed very close to ...