One of my favorite songs from the 1960s is The Zombies’ “She’s Not There,” a blast of anxious pop music about a girl whose most fascinating quality is that she is nowhere to be found. One of my favorite themes from the January meeting of the American Astronomical Society in Long Beach, California, might be called “Discoveries That Aren’t There”: Several major teams of researchers presented studies that definitively did not find what they were looking for, and that were all the more fascinating for it.