BLACK HOLES curve the fabric of spacetime so extremely that it rends. The superdense objects devour anything—even light—that strays too close, a trip from which there is no escape. Perhaps their most singular power, however, is their hold on our imagination. Learning more about these implacable gluttons offers the same shivery frisson as watching a stalking horror-movie creature while knowing we are safe in our cushioned seats.
As the authors in this special issue explain, black holes offer much more to science than the can’t-look-can’t-look-away spectacle of destruction. The forces they unleash shape the regions around them, providing clues to the evolution of stars and galaxies. For instance, the dark sinkholes reveal a surprising bright side. In their quest to solve an enduring mystery, astronomers have learned that black holes are responsible for some of the most dazzling fireworks in the universe. When a massive star collapses to birth a black hole, it releases a titanic pulse of radiation in a gamma-ray burst that can be seen from billions of light-years away, as Neil Gehrels, Luigi Piro and Peter J. T. Leonard discuss in their article, “The Brightest Explosions in the Universe,” starting on page 34. Greedily feeding supermassive black holes also exist in regions called starbursts, where stars are forming at a phenomenal rate. How? Turn to page 42 for “The Galactic Odd Couple,” by Kimberly Weaver.
Studying black holes yields insights into other mind-bending areas of physics. In the coming years the highest-energy particle accelerators on earth might be able to produce distant cousins of the astrophysical behemoths: microscopic black holes. They would explode immediately after they formed, giving clues about how spacetime is woven together and whether it has unseen higher dimensions, explain Bernard J. Carr and Steven B. Giddings in “Quantum Black Holes.” The article starts on page 20. Still other features in the issue explore what black holes can tell us about time travel, the nature of gravity, the ultimate amount of information the universe can hold and whether our seemingly 3-D reality is actually an illusion. So draw up that comfortable chair and get ready to learn more about one of the most awesome beasts in the universe.