The first picture ever captured of a black hole, one situated in the center of another galaxy, was pretty blurry. Seen in silhouette, it appeared fuzzy, as did the ring of hot gas surrounding it. The reaction of the public did not necessarily match the unalloyed joy of astronomers accustomed to extracting cosmic wonders from lines in a graph. To anyone more familiar with black holes from epic space films, this one mostly looked like a flame-glazed donut.
But that portrait is one of the most extraordinary achievements in modern science, a display of humankind’s capacity to reach across light-years. Not so long ago, scientists couldn’t say with much confidence that black holes existed, nor did they know that a giant one sits at the center of our own galaxy.
Yesterday, the Nobel Committee recognized decades of black-hole research by awarding its physics prize to three scientists. Half the prize went to Roger Penrose, of the University of Oxford, who showed that black holes could exist, and half went to Reinhard Genzel, of the Max Planck Institute for Extraterrestrial Physics and UC Berkeley, and Andrea Ghez, of UCLA, who provided the most convincing evidence that a particular black hole—the supermassive one at the center of our Milky Way—did. (Ghez, it’s worth noting, is only the fourth woman to receive the honor in nearly 120 years of Nobel history.)
Black holes are among the most mysterious phenomena in the universe. Forged from the cores of dead stars, they are so dense that nothing can escape their gravitational pull, not even light, which renders them invisible. Entire stars, once luminous, can be extinguished if they cross a black hole’s boundary, and pass the point of no return. [Continue reading…]