Four hundred years after Galileo Galilei pointed the first telescope at the stars, astronomers devised instruments that could look beyond what optical telescopes reveal. The Chandra X-Ray Observatory, launched on July 23, 1999, aboard the space shuttle Columbia, is a highly sophisticated descendant of the early X-ray instruments. Orbiting 85,000 miles above Earth and operated by the Smithsonian’s Astrophysical Observatory in Cambridge, Massachusetts, the telescope is designed to detect X-ray emissions from extraordinarily hot regions of the universe. Over nearly two decades, Chandra has revealed a universe of violent and extreme environments. With it, scientists have studied intense gravitational and magnetic fields around black holes, supernova shock waves, and titanic collisions between clusters of galaxies.
Text adapted from Chandra’s Cosmos: Dark Matter, Black Holes, and Other Wonders Revealed by NASA’s Premier X-ray Observatory by Wallace H. Tucker, to be published on March 28, 2017, by Smithsonian Books.
The Spread of Star Stuff
In massive stars, nuclear fusion turns hydrogen into helium, and eventually into heavier elements. Stellar winds and supernova explosions, which occur once the star uses up its fuel, spread these heavy elements out into space. One of Chandra’s greatest successes has been in tracking how those elements spread through and even between galaxies.
Chandra images, like the one above of galaxy M82, show the speed of supernova shock waves spreading oxygen, silicon, sulfur, calcium, and iron. Those elements may eventually coalesce to create new stars with planets. Chandra has even detected oxygen produced in some of the first supernovas, 10 billion years ago, in filaments of gas, millions of light-years long, stretching between galaxies.