Speaker 1: Welcome to Brainstuff, a production of iHeart Radio. Hi brain Stuff.
Speaker 1: I'm Lauren Bogelbaum, and today's episode is a classic from
Speaker 1: our erstwhile host, Christian Sager. This one is about one
Speaker 1: of the many amazing observations that researchers have made about
Speaker 1: black holes over the past few years, and how it
Speaker 1: proves Einstein's theory of relativity to be correct once again.
Speaker 1: Hey brain Stuff, it's Christian Sager. Scientists always seem to
Speaker 1: be finding new evidence of Albert Einstein being right. The
Speaker 1: latest example comes from astronomers using the European Southern Observatories
Speaker 1: very large telescope in Chile. Astronomers there have been studying
Speaker 1: the stars at orbit dangerously close to the supermassive black
Speaker 1: hole in the center of our galaxy to find that
Speaker 1: you guessed it. Einstein's landmark theory of general relativity is
Speaker 1: holding strong, even at the doorstep of the most extreme
Speaker 1: gravitate sational field in our galaxy. Most galaxies are known
Speaker 1: to have super massive black holes lurking in their cores.
Speaker 1: In our galaxy, the Milky Way is no different. Located
Speaker 1: approximately twenties six thousand light years from Earth, our black
Speaker 1: hole behemoth is called Sagittarius A, and it has a
Speaker 1: mass four million times that of our Sun. Astrophysicists are
Speaker 1: hugely interested in black holes, as they're the most compact,
Speaker 1: gravitationally dominant objects known in the universe, and therefore an
Speaker 1: extreme test for relativity. By tracking the motion of stars
Speaker 1: orbiting close to Sagittarius A, a team of German and
Speaker 1: Czech astronomers have analyzed twenty years of observations made by
Speaker 1: the Very Large Telescope and other telescopes using a new
Speaker 1: technique that pinpoints the positions of these stars. One of
Speaker 1: the stars, called S two, orbits Sagittarius A every sixteen
Speaker 1: years and zooms very close to the black hole, around
Speaker 1: four times the distance between Neptune and our Sun. Because
Speaker 1: of its racetrack orbit deep inside the black hole's gravitational well,
Speaker 1: S two is treated as a natural relativity probe into
Speaker 1: this mysterious strong gravity environment. By precisely measuring its motion
Speaker 1: around the black hole, the researchers could compare its orbit
Speaker 1: with predictions laid out by classical Newtonian dynamics, and they
Speaker 1: found that the star's actual orbit deviated from Newtonian predictions
Speaker 1: exactly as predicted by Einstein's general relativity, although the effect
Speaker 1: was slight. Here's a quick example of Einsteinian gravity at work.
Speaker 1: If you have a massive object, it will bend space time,
Speaker 1: like the famous example of the bowling ball suspended it
Speaker 1: on a rubber sheet. If another object travels past the
Speaker 1: massive object, the curvature of space time will deflect its
Speaker 1: direction of motion, like a marble rolling past the bowling ball. Now,
Speaker 1: in two thousand and eighteen, S two will swoop to
Speaker 1: its closest point in its orbit around Sagittarius A, and
Speaker 1: astronomers using the Very Large Telescope are preparing a new
Speaker 1: instrument to get an even more precise view of the
Speaker 1: extreme environment surrounding the black hole, called gravity and that's
Speaker 1: gravity in all caps. The instrument is installed on the
Speaker 1: Very Large Telescopes Interferometer, and astronomers not only predict that
Speaker 1: it will get an even more precise gauge on Einstein's
Speaker 1: general relativity, it might even detect deviations away from relativity,
Speaker 1: possibly hinting at new physics beyond relativity. An update the
Speaker 1: research that came out in eighteen was also groundbreaking. It
Speaker 1: was the best evidence would record it yet, but Sagittarius.
Speaker 1: A star is indeed a black hole and not a
Speaker 1: different kind of phenomenon. Today's episode was written by Ian
Speaker 1: O'Neill and produced by Dylan Fagan and Tyler Clang. For
Speaker 1: more and listen lots of other massive topics, visit houstof
Speaker 1: works dot com. Brain Stuff is production of iHeart Radio
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