The Amelia Earhart disappearance hasn't actually been a mystery so much as a jumping-off point for as many fantastical theories as possible. Earhart had often been credited as a better self-promoter and daredevil than a pilot. Her last stunt, in 1937, was an attempt to make the record books as the first woman to circumnavigate the globe in an airplane. During the final leg of her journey she, her navigator, and her plane all vanished.
Some people thought she was captured, tried, and executed as a spy by the Japanese. Some people thought she actually was a spy and went into hiding after returning from her last mission. There are probably some alien abduction theories floating around.
Most sane theories hold that she crashed. These theories seem to be supported by the discovery of a woman's corpse on an island in 1940. The three year time lapse did not do the body good. Much of it was carried off by wildlife, but the basic description matched Earhart, and some debris found near the body indicated that it might be her. Unfortunately, in 1940 there was a lot going on in the Pacific, and all but an incomplete bone was lost.
That the bone is hers is unlikely. For a body that could be anywhere in the Pacific Ocean to wash up on an island, and for only the famous Earhart (but not her relatively unknown navigator) to be found, and for anything that might prove the body belonged to someone else to subsequently be lost, is pretty fishy. And people have been burned when it comes to 'genuine' Earhart memorabilia in past. A lock of her hair belonging to the International Woman's Air and Space Museum turned out to be thread.
Scientists have come up with a new way to check the DNA of the bones against known Earhart DNA. Amelia Earhart corresponded with a lot of people. This was before envelopes with adhesives that don't require wetting, and she would have licked the envelopes. Since she was famous during her time - thanks to that gift for promotion - people kept her letters. What's more, many of them opened the letters by slitting the side with a letter opener instead of tearing open the whole thing like modern barbarians. The saliva on the letter, held by adhesives for three-quarters of a century, may be extractable. If it is, then it can be checked against the bones, and end the conspiracy theories altogether.
Via National Geographic.