Even if you’re not an Astro-nerd, this is pretty dadgum interesting, and I’m’a gonna ‘splain why.
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There’s a supermassive black hole in the constellation Sagittarius called Sagittarius A (always so clever, those astrophysicists). Sag A is surrounded by big, burly stars. One of these stars (called S2) orbits Sagittarius A in a long, elliptical orbit. But unlike under normal celestial circumstances, two unusual things happen as S2 nears the black hole.
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1) Its orbit shifts slightly in advance of its previous pass. Every sixteen years, the same slight “glitch.” So if you were to plot its course, rather than looking like a series of overlying ellipses, it would look like a bent helix. Or a Slinky. Astrophysicists call this phenomenon “orbital precession.”
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2) As S2 nears Sagittarius A (perihelion) its light becomes red-shifted. That is, the light we’re capable of observing from it is being shifted towards the red end of the spectrum. Again, like a Slinky, only stretched instead of bent.
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So why would that be? The standard explanation for red-shifting is when an object is receding from us, its light signature gets stretched. The higher the velocity, the deeper the red-shift. And (normally), the farther away it is. True, true & true. But in this case, Sagittarius A is like a ginormous vacuum cleaner sucking in everything in the neighborhood, including photons of light from stars that pass too close to its gravity well. And every sixteen years, S2 comes within 18B km of this monster.
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So why should anybody care about any of this?
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Because this was predicted by Albert Einstein 105 years ago, though neither have ever been observed in nature before. Until now.
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Link to the story:
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https://www.syfy.com/syfywire/einsteins-hand-reaches-out-from-a-black-hole-and-torques-a-stars-orbit