"Black holes are intrinsically interesting," says Robert Irion, "because they're just so strange and exotic and seem like something out of science fiction." But they're quite real. "There's no longer a debate that they exist. What people may not realize is that it appears as if all major galaxies—our Milky Way, the neighboring Andromeda and all the other galaxies that the Hubble telescope can see—have these giant black holes at their centers, millions of times or even a few billion times as massive as our sun. That's something that came as a surprise in the last decade even to astronomers and is only now becoming broadly accepted by the astronomy and astrophysics communities. It has profound implications for our understanding of how galaxies themselves arose and how they evolved over time."
Much of this new research has been made possible by the laser system at the W. M. Keck Observatory in Hawaii. Because of this technology, Irion says, "astronomers can see stars close to the center of our galaxy that dive very close to the black hole and then orbit out again. It's like looking at comets orbiting around our sun, except they're not comets—just ten miles across—but stars ten times bigger than our sun orbiting at up to 3 percent of the speed of light." Irion, who wrote our cover story, has written about astronomy for more than a decade. But this assignment marked his first trip to Keck. That's where he was, standing outside waiting for technicians to get the system up and running, when the laser came on. "I quite literally gasped," he says, "and it wasn't from a lack of oxygen. It was such a stunning sight, almost like viewing a work of art."
For our probing piece about how the assassination of Martin Luther King Jr. and the urban riots that followed not only affected Lyndon Baines Johnson's presidency but also reshaped the American political landscape, Clay Risen spent many hours in Johnson's presidential museum and archives in Austin, Texas, and at the National Archives branch in College Park, Maryland. He also talked to quite a few LBJ staffers—not only key decision makers like Joseph Califano, Harry McPherson and Roger Wilkins, but more junior staffers who, Risen says, "were actually doing a lot of the grunt work and advising the advisers." But Risen's eureka moment came when he ran across a memo that Califano had written to Johnson after King's assassination advising the president to appear before a joint session of Congress to push for social programs. On the memo, Johnson had scrawled: "I promised nothing. I stated my intentions only. Since changed by riots."
Risen says, "This is the kind of moment every researcher lives for, when you find that document that embodies perfectly the argument you're trying to make."
The 50 finalists of our 5th Annual Photo Contest go on display at Smithsonian.com April 1 (no April Fools' jokes, please). This year, in addition to the usual winners in each of five categories and a Grand Prize winner chosen by our judges, readers will be able to select a seventh, Readers' Choice winner, by voting online at Smithsonian.com. All seven winners will be announced in early summer.