Imagine standing on the edge of a giant crater, knowing nothing about how this massive hole in the ground came to be. Or figuring out that a cataclysmic event like an asteroid hitting the Earth killed the dinosaurs, but having no visible evidence on the planet of a collision of that magnitude. Scientists and explorers have faced such puzzling moments in our history. They may have had inklings that giant collisions happened in the universe, but where and how and whether they still happened are things that modern scientists are…
