Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more . CNN  —  The disappearance of pioneering aviator Amelia Earhart more than 87 years ago has remained one of the most captivating mysteries in history, with a handful of explorers devoted to scouring the seas for any clue to her final whereabouts. Sonar imagery captured in January revealed a plane-shaped anomaly on the seafloor about 100 miles away (161