![]() Ground-based telescopes, which monitor the brightness of millions of stars in the rich star fields toward the central bulge of our Milky Way, look for a tell-tale sudden brightening of one of them when a massive object passes between us and the star. However a black hole warps space, which then deflects and amplifies starlight from anything that momentarily lines up exactly behind it. Telescopes can't photograph a wayward black hole because it doesn't emit any light. Because the self-detonation is not perfectly symmetrical, the black hole may get a kick, and go careening through our galaxy like a blasted cannonball. These stars explode as supernovae, and the remnant core is crushed by gravity into a black hole. The nearest star to our solar system, Proxima Centauri, is a little over 4 light-years away.īlack holes roaming our galaxy are born from rare, monstrous stars (less than one-thousandth of the galaxy's stellar population) that are at least 20 times more massive than our Sun. However, its discovery allows astronomers to estimate that the nearest isolated stellar-mass black hole to Earth might be as close as 80 light-years away. The newly detected wandering black hole lies about 5,000 light-years away, in the Carina-Sagittarius spiral arm of our galaxy. Stellar-mass black holes are usually found with companion stars, making this one unusual. Until now, all black hole masses have been inferred statistically, or through interactions in binary systems or in the cores of galaxies. Following six years of meticulous observations, NASA's Hubble Space Telescope has, for the first time ever, provided direct evidence for a lone black hole drifting through interstellar space by a precise mass measurement of the phantom object. But, statistically, this detection means that the nearest wandering black hole to Earth could be no more than 80 light-years away.Īstronomers estimate that 100 million black holes roam among the stars in our Milky Way galaxy, but they have never conclusively identified an isolated black hole. No need for us to worry because the black hole is 5,000 light-years away. The black hole's powerful gravitation left a unique fingerprint on the deflection of starlight, eliminating other potential gravitational lensing candidates. This was a long and painstaking measurement that the Hubble Space Telescope's exquisite resolution is well-suited for. The light from a star far behind the black hole was momentarily brightened and deflected by the black hole passing in front of it. Now, astronomers have at last come up with clear evidence for finding one in a needle-in-a-haystack search among a blizzard of stars seen toward the galactic center. But since black holes emit no light of their own, they are extremely difficult to detect. And this is how the phantom black holes are found.Īstronomers estimate that there should be 100 million black holes roaming among the 100 billion stars in our galaxy. Starlight passing near this gravitational pothole in space is deflected. ![]() The intense gravity from something so dense warps the fabric of space around it, like a bowling ball rolling across the skin of a trampoline. The black hole is typically several times the mass of our Sun. That only begins to describe the infinite density locked away into a black hole left over from a stellar explosion. Imagine crushing the mass of a fleet of battleships into something no bigger than a baseball. Like legendary wandering ghosts, their presence can only be deduced by seeing how they affect the environment around them. These black holes cannot be directly seen because their intense gravity swallows light. The vast gulf of space between the stars is plied by the dead, burned-out and crushed remnants of once glorious stars. Four Successful Women Behind the Hubble Space Telescope's Achievements.Characterizing Planets Around Other Stars.Measuring the Universe's Expansion Rate.
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