Things were not going well for Amelia Earhart on the morning of 2 July 1937. Around 19 hours earlier, she’d taken off from New Guinea bound for Howland Island, a minuscule, 0.7-square mile (1.8-square kilometre) speck of land situated between Hawaii and Australia. She had already travelled 22,000 miles (35,400 km) around the equator, and just 7,000 miles (11,300 km) of Pacific Ocean stood between her and the record for world’s longest round-the-world flight. But one by one, problems had been accumulating on that fateful flight. Now, it was becoming apparent that not just her goal, but also her life was at stake.

“We must be on you, but cannot see you – but gas is running low,” she radioed to the United States Coast Guard ship assigned to help guide Earhart and her navigator, Fred Noonan, to Howland Island. Due to a series of still-debated misunderstandings and errors, the pair could not hear any of the voice transmissions from the ship, and their attempts to use radio navigation to locate the island failed.

At 8:43 am, reportedly sounding close to tears, Earhart broadcast her last known transmission – “We are on the line 157 337... We are running on line north and south” – indicating that she was following a particular bearing in the hope of stumbling across her destination. As history shows, she never made it.

Few missing persons have inspired such enduring intrigue as Earhart. After her disappearance, the US government offered $4 million – the most ever spent on search and rescue until that time – on a 17-day air and sea mission to find her. Rumours and outlandish theories of what became of Earhart – that she was captured and executed by the Japanese; that her disappearance was a hoax so she could assume an alternate identity as a New Jersey housewife – made their way into popular culture. Most assumed Earhart simply crashed into the ocean and died.

There is another possibility, however.

Some evidence indicates that Earhart may have become a castaway on Nikumaroro Island (formerly known as Gardner Island), an uninhabited atoll about 350 miles south of her intended destination. For five nights after Earhart disappeared, the Navy picked up distress signals originating from bearings crossing Nikumaroro. It took them a week to get a battleship carrying airplanes out to the remote island, and by that time the signals had stopped. When the planes flew over Nikumaroro, the pilots saw no sign of Earhart or of recent habitation. The Navy wrote the signals off as bogus.

‘Skeleton, Human…’

Three years later, a British coconut harvesting expedition to the island found a partial skeleton of what appeared to be a castaway. Giant coconut crabs, apparently, had dismembered and carried off many of the bones, but the crew collected those that remained. They gathered up a few other items found at the scene, including pieces of a woman’s and a man’s shoe and a box that once contained a navigational device. In the spring of 1941, the bones arrived in Fiji, where a local doctor examined them and concluded they came from a short, stocky man. The bones and objects subsequently disappeared, and only a few dozen members of the British colonial administration ever heard about the findings.

Few people believed the whispered, lingering rumours about the mysterious skeleton until, in 1997, the original paperwork turned up. Peter McQuarrie, a member of the International Group for Historic Aircraft Recovery, or TIGHAR, stumbled across a file labeled “Skeleton, Human, finding of, Gardner Island” while conducting research at the National Archive of Kiribati, in Tarawa. Those documents led TIGHAR to the archive of the British Western Pacific High Commission, located at the time in the basement of a secure government communications facility in Hanslope Park, around 60 miles north-west of London. In 1998, TIGHAR secured clearance to enter the Hanslope facility and discovered the remainder of the paperwork related to the bones.

For TIGHAR members, this served as a sort of eureka moment. The group had already been leading excursions to the island since 1989, slowly gathering evidence – a piece of a plane that didn’t match any from World War II, a woman’s shoe heel – that hinted at Earhart’s possible presence but never confirmed it definitively. TIGHAR asked two forensic anthropologists to examine the Fijian doctor’s notes. Both concluded that he had been mistaken in his interpretation. The bones actually belonged to a woman, most likely of northern European descent, who stood around five feet and seven inches tall.

Encouraged, the TIGHAR team subsequently carried out three archaeological surveys on the island, uncovering artifacts that speak of an American woman from the 1930s, including a broken compact, personal care products and anti-freckle cream (Earhart reportedly considered her freckles unattractive). A bone fragment that came from a human fingertip raised hope, but geneticists at the University of Oklahoma were unable to recover enough mitochondrial DNA to test it against samples provided by the Earhart family.

Evidence pointed towards Earhart possibly landing in the coral reef surrounding Nikumaroro. It would have been low tide when she landed, meaning her plane could have stayed upright long enough for her to send out distress signals. Eventually, TIGHAR members hypothesise, the tide washed it down the steep reef shelf, engulfing it in several hundred feet of ocean. A photo taken by a British expedition in 1937, three months after Earhart’s disappearance, reveals an object sticking out of the reef that should not exist on an uninhabited island. The US State Department confirmed that the debris could be a piece from a Lockheed Electra 10E, Earhart’s plane, as did independent forensic examiner Jeff Glickman.

“I think the fact that we have a photograph of an object on the reef that was taken 90 days after she was lost and, by every measure, has the right configuration for being Lockheed Electra 10E landing gear is pretty convincing,” says Glickman, who specialises in image analysis.

New clues

Last summer, TIGHAR returned to the island for the tenth time and deployed a Bluefin-21 autonomous underwater vehicle (AUV) to collect sonar imagery of the vertical face of the reef for the first time. The AUV gathered dozens of hours of recordings by scanning from the shallows to the depths in the area near the unknown object pictured in the 1937 photograph. Nothing of note turned up during the trip, but in March, a TIGHAR forum member spotted an anomaly in that data. Further analysis revealed a large object, about the size and shape of the Lockheed Electra’s wing or fuselage. Another $2-3 million dollar expedition will be required in order investigate the anomaly up close, to see whether it is an odd coral formation, a sunken ship or, perhaps, the evidence that solves the Earhart mystery. “What we need is that last piece, the thing that connects all other evidence to Earhart,” says Ric Gillespie, TIGHAR’s founder and executive director.

“I think we’ll find the plane,” Glickman adds confidently. “My goal is to get it back to the Smithsonian [Museum] where we can have an intelligent conversation about the courageousness of this woman and what she accomplished.”

A tin box in New Zealand discovered earlier this month by an archivist at the New Zealand Air Force Museum in Christchurch may also offer vital clues. Containing a slip of paper with the words “Gardner Island”, the box is said to contain 45 aerial photos taken for the New Zealand Pacific Aviation Survey 15 months after Earhart’s disappearance, which could provide detailed views of the area.

If Earhart did crash land on Nikumaroro, her last days were most likely a struggle. “There are a lot of ways to die on that island,” Gillespie says. “I’ve [accidentally] tried several of them.”

No freshwater exists, save that that falls out of the sky. Plenty of fish and marine birds inhabit Nikumaroro and its surrounding waters, but a person could still starve to death if they expended more energy chasing after darting fish and skittish birds than those small snacks would provide. Alternatively, falling on the jagged reef while hunting for food or checking the plane could have resulted in lacerations, making a fatal infection more likely. Gillespie does not know how long the castaway survived, but speculates weeks to months, not a year. Archeological evidence has revealed a campfire pit, animal bones and partially melted broken bottles – perhaps used for sterilising water. “It’s honestly a tragic tale,” Gillespie says. “Someone was really using their imagination, working hard, but ultimately not making it.”

TIGHAR has searched available historical documents – Lloyd’s shipping records, Colonial Service records, newspapers and more – and has not found any accounts of Europeans who went missing in the South Central Pacific between 1933, the date stamped on the glass bottles found at the castaway’s campfire site, and 1940, when the bones were found.

Still, the evidence on Nikumaroro could turn out to be an odd coincidence and wishful thinking, meaning that the castaway’s bones actually belong to some other poor, stranded soul. In this scenario, Earhart simply crashed into the ocean and died on impact – probably a preferable ending to being eaten by giant coconut crabs.

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