It’s a balmy tropical night south of the equator in the Pacific Ocean, but inside the control room of the E/V Nautilus it’s cold and dark and hushed. Banks of monitors provide the only light. Moving around is treacherous—wires hang along the walls and the space between work stations is narrow. Despite the heat outside, crew members wear fleece to fend off the frigid air. Their voices are barely audible as they speak softly to each other through headsets.

The screens mounted on the black-painted walls provide a vision of another world. One shows a remotely operated vehicle (ROV) floating in shadowy blue light, dwarfed by what looks to be a massive cliff face. Another screen provides a closer view—bedrock and coral rubble occasionally obscured by a flurry of marine snow.

View Images Amelia Earhart strides in front of her Lockheed Electra, the plane in which she disappeared in July 1937 while attempting to become the first woman to fly around the world. Alamy Stock Photo

“We’re looking for colors that aren’t natural to the background,” says Robert Ballard, as he stares intently at the screens from his perch in the back row. The man who found the Titanic is on a mission to find out what happened to Amelia Earhart when she disappeared during her quest to be the first woman to fly around the world.

Earhart would likely have been enraptured by the ship’s space-age display. The aviator always had her eye on the future, whether it was records to be broken in the skies or new paths to be forged by women. She even ventured underwater in an early version of a diving suit.

Yet she would have been astonished at the technological wonders being marshaled to discover her fate.

View Images Inside the control room, crewmembers pilot remotely-operated vehicles (ROVs) and keep round-the-clock vigil in four-hour shifts. Photograph by Spencer Smith, National Geographic

Ballard has directed his state-of-the-art ship, the E/V Nautilus, to the waters off Nikumaroro, an isolated ring of coral and sand surrounding a turquoise lagoon. Only four and a half miles long and one and a half miles wide, the island appears on most maps as a mere speck in the vast Pacific Ocean.

“There are various theories about where Amelia’s plane landed, and some of them are a little wild,” says Ballard, a National Geographic Explorer. Some people believe Earhart and navigator Fred Noonan ended up in the Marshall Islands, some say Saipan or even New Jersey, others that the plane crashed and sank. “We’re going with the one that she actually landed.”

On July 2, 1937, Earhart and Noonan were aiming for Howland Island, which is even smaller than Nikumaroro. After taking off from Lae, New Guinea, on the third to last leg of Earhart’s attempt to circumnavigate the globe, they failed to locate Howland and vanished without a trace.

The International Group for Historic Aircraft Recovery (TIGHAR) has spent the last several decades investigating the hypothesis that Earhart and Noonan landed their Lockheed Electra 10E on Nikumaroro when they couldn’t find Howland.

The researchers base their hypothesis on Earhart’s last radio transmissions. At 8:43 a.m. on July 2, Earhart radioed the Itasca, the U.S. Coast Guard cutter awaiting Earhart at Howland: "KHAQQ [the Electra's call letters] to Itasca. We are on the line 157 337." The Itasca received the transmission but couldn't get any bearings on the signal.

The “line 157 337” indicates that the plane was flying on a northwest to southeast navigational line that bisected Howland Island. If Earhart and Noonan missed Howland, they would fly either northwest or southeast on the line to find it. To the northwest of Howland lies open ocean for thousands of miles; to the southeast is Nikumaroro.

View Images Outfitted with an array of underwater sensors, E/V Nautilus works a grid-like search pattern Ballard likens to "mowing the lawn." Photograph by Ernie Kovacs, National Geographic

The line-of-position radio message was the last confirmed transmission from Earhart, but radio operators received 57 messages that could have been from the Electra. Wireless stations took direction bearings on seven of them. Five of those crossed near Nikumaroro, then called Gardner island.

At the time of Earhart’s disappearance, the tide on Nikumaroro was especially low, revealing a reef surface along the shore long and flat enough for a plane to land. If Earhart sent any of those 57 radio transmissions, the plane must have landed relatively intact.

The TIGHAR researchers theorize that Earhart and Noonan radioed at night to avoid the searing daytime heat inside the aluminum plane. Eventually the tide lifted the Electra off the reef, and it sank or broke up in the surf. The last credible transmission was heard on July 7, 1937.

Earhart Mystery On May 20, 1937, Amelia Earhart and navigator Fred Noonan took off from Oakland, California on the first leg of their historic round-the-world flight. They disappeared 43 days later while trying to locate tiny Howland Island in the remote Pacific. The flight plan After a westbound attempt in March that failed with a crash in Hawaii, Earhart decided on an eastbound route that would cover nearly 29,000 miles. Oakland, Calif. May 20 May 22 May 21 U.S. Saint-Louis June 8 June 1 May 23 June 2 June 4 June 3 June 6 June 7 Saint-Louis June 8 June 19 June 18 June 13 June 20 June 11 June 14 June 17 June 10 June 15 Bangkok SIAM June 20 June 12 June 13 Oakland, Calif. Bangkok SIAM June 20 Honolulu, Hawaii (U.S.) June 21 Lae N.E. NEW GUINEA (AUS.) July 2 June 24,27 Howland I. (U.S.) June 25 Gardner I. (Nikumaroro) (U.K.) June 28 June 29 Missed rendezvous Howland Island, with its rudimentary airstrip, was Earhart’s next stop. U.S. Coast Guard Cutter Itasca was on station, receiving the pilot’s last radio transmissions. In her last heard in-flight message, Earhart reported flying along the 157°/337° line. Nikumaroro is southeast of Howland Island along it. Last reported navigational line Howland I. U.S.C.G.C. Itasca N.E. NEW GUINEA (U.S.) EQUATOR Gardner I. (Nikumaroro) (AUS.) (U.K.) PACIFIC OCEAN Lae New Guinea Enlarged BELOW PAPUA (AUS.) 400 mi AUSTRALIA 400 km Earhart’s final landing? S.S. Norwich City wreck Years of research and many archaeological expeditions strengthen the case that Earhart landed on this isolated atoll. Nikumaroro Beach Reef Castaway camp Aircraft wreckage MATTHEW W. CHWASTYK, NGM STAFF. BOUNDARIES AS OF 1937 ARE SHOWN. SOURCES: THE INTERNATIONAL GROUP FOR HISTORIC AIRCRAFT RECOVERY; NASA, LANDSAT; U.S. STATE DEPARTMENT Earhart Mystery On May 20, 1937, Amelia Earhart and navigator Fred Noonan took off from Oakland, California on the first leg of their historic round-the-world flight. They disappeared 43 days later while trying to locate tiny Howland Island in the remote Pacific. Missed rendezvous Howland Island, with its rudimentary airstrip, was Earhart’s next stop. U.S. Coast Guard Cutter Itasca was on station, receiving the pilot’s last radio transmissions. Saint-Louis FR.W. AFRICA June 8 Calcutta June 18 Karachi June 17 Khartoum June 13 Gao June 11 INDIA (U.K.) Dakar FR.W.AF. June 10 Assab, June 15 Massawa ITALIAN W. AF. June 14 Akyab (Sittwe) BURMA (U.K.) June 19 Oakland, Calif. Oakland, Calif. May 20 Akyab (Sittwe) BURMA (U.K.) June 19 Fort Lamy (N’Djamena) FR.EQUA.AF. June 12 U.S. Saint-Louis FR.W. AFRICA June 8 Tucson, Ariz. May 22 Burbank, Calif. May 21 El Fasher ANGLO-EGYPTIAN SUDAN June 13 Rangoon June 20 Honolulu, Hawaii (U.S.) Miami, Fla. June 1 Bangkok SIAM June 20 New Orleans, La. May 23 San Juan, P.R. June 2 Singapore (U.K.) June 21 Fortaleza June 6 Fortaleza June 6 Caripito VENEZUELA June 3 Bandung NETH. INDIES June 24,27 Howland I. (U.S.) Surabaya June 25 Natal June 7 Gardner I. (Nikumaroro) (U.K.) Paramaribo SURINAME (NETH.) June 4 Darwin June 29 Lae N.E. NEW GUINEA (AUS.) July 2 The flight plan Kupang (PORT.) June 28 After a westbound attempt in March that failed with a crash in Hawaii, Earhart decided on an eastbound route that would cover nearly 29,000 miles. AUSTRALIA BRAZIL Last reported navigational line 500 mi Gilbert Islands Earhart’s final landing? S.S. Norwich City wreck 500 km U.S.C.G.C. Itasca Howland Island (U.S.) Years of research and many archaeological expeditions strengthen the case that Earhart landed on this isolated atoll. (U.K.) EQUATOR Baker Island (U.S.) Nauru (U.K.) Phoenix Islands Bismarck Archipelago N.E. NEW GUINEA (U.K.) Nikumaroro Enlarged at right Gardner I. (Nikumaroro) (AUS.) Beach (U.K.) Lae (U.K.) PACIFIC OCEAN (U.K.) Tokelau Islands PAPUA Reef Santa Cruz Is. Castaway camp (AUS.) (N.Z.) (U.K.) (U.K.) Clues from final radio contact (U.S.) Wallis I. Savaii (FRANCE) In her last in-flight radio message heard by Itasca, Earhart reported flying along the 157°/337° line. Nikumaroro is southeast of Howland Island along it. Aircraft wreckage Samoa Islands Fiji (U.K.) MATTHEW W. CHWASTYK, NGM STAFF. BOUNDARIES AS OF 1937 ARE SHOWN. SOURCES: THE INTERNATIONAL GROUP FOR HISTORIC AIRCRAFT RECOVERY; NASA, LANDSAT; U.S. STATE DEPARTMENT Viti Levu (U.K. & FR.)

Members of TIGHAR have traveled to the island 13 times, but never with the technological tools that Ballard has at his disposal. The Nautilus is equipped with a multi-beam sonar on the hull, two ROVs with high definition cameras, an autonomous surface vehicle (ASV), and multiple drones—plus Ballard’s years of experience finding treasures under the sea.

On this expedition he’s aiming to discover where Earhart’s plane ended up after it tumbled off the reef.

It’s painstaking work. The Nautilus didn’t approach the island directly but took a sweeping path that allowed the sonar to map the underwater terrain. But the ship couldn’t get too close; the reef is extremely dangerous, as demonstrated by the wreckage from the S.S. Norwich City that still dominates the northeastern shore of the island.

View Images Ballard's search centers on Nikumaroro Island, an uninhabited atoll that's part of the Micronesian nation of Kiribati. Some researchers believe Earhart and navigator Fred Noonan landed here and died as castaways. Photograph by Rob Barrel, NAI'A Fiji

Once the Nautilus arrived at the island, a routine quickly developed: Send out the ASV (essentially a robot boat) to map the terrain near the surf. When it returns, analyze the data to see what, as Ballard puts it, “comes out of the soup.” Ballard and his colleagues are looking for targets—anomalies—though a lack of them doesn’t mean nothing interesting lies below the waves.

Ballard puts great stock in laying eyes on his quarry. “Everything I ever found was found visually,” he says.

Expedition Amelia Ocean explorer Robert Ballard, discoverer of the Titanic, is searching for Amelia Earhart’s airplane. Watch a preview of the two-hour National Geographic special premiering October 20, 2019.

That’s where the ROVs come in. Usually launched at night, they can go as deep as 4,000 meters. Hercules, a bright yellow box with a metal base, offers the first-person view, while smaller Argus keeps a camera pointed at Hercules.

The ROV pilots operate on four-hour shifts day and night, and mostly they don’t see much. But on the first night they found wreckage—items that looked to be a propeller, a boiler, a crank shaft, and much more—all from the Norwich City.

It wasn’t the wreck Ballard was looking for, but it answered an important question: How deep could the plane go? The Norwich City debris clustered at depths between 100 to 300 meters. “Anything of similar mass—part of a plane or part of a ship—would have been sliding down slope in that zone,” explains expedition leader Allison Fundis. “We’re really focusing on that zone with the ROV dives.”

Earhart’s custom- built aircraft For her flight around the world in 1937, Amelia Earthart chose one of the most advanced aircraft of her time, the Lockheed Electra 10E. Modifications included additional fuel tanks, an autopilot, and special windows for the navigator. Radio direction finder Antenna Navigator's station 2 Toilet 3 3 Auxiliary battery 1 Transmitter Pratt & Whitney Wasp S3H1 Engine 1 The engine Earhart's airplane was only the fifth Electra equipped with new and more powerful 550- horsepower engines. 2 Navigation aids The Electra had a radio direction finder coupled to a manually-rotated loop antenna located over the cockpit. 3 Extra fuel tanks Earhart removed the plane's seats to add six fuel tanks, making it necessary to crawl over the tanks to reach the cockpit. 6 Extra tanks 6 Regular tanks Total capacity 1,151 gallons Cabin materials Aluminum thickness U.S. quarter (for comparison) 0.069” A B C A Cloth headliner Thicker part (belly) 0.040” Thinner part (nose, tail) 0.025” Foil moisture barrier B Aluminum C Radio problems Earhart reported her progress to the Coast Guard cutter Itasca, awaiting her arrival at Howland Island. But she was unable to hear their replies, perhaps due to the loss of an antenna. 38’7’’ 1. Ventral antenna 2. Trailing wire antenna 1. The lost antenna On its last takeoff, the plane's ventral antenna suffered damage, a possible cause of the communication failure experienced later. 2. Trailing wire antenna To reduce weight, Earhart removed this antenna used for the international distress frequency. It could be extended 250 feet. Reef landing Some think Earhart landed on the flat reef at Nikumaroro Island during low tide. The plane may have remained there several days before rising tides washed it into the ocean. The plane may have broken up in the surf or floated away to sink in deep water. Nikumaroro Island 3,281 ft (1,000m) AREA ENLARGED Plane Reef 2,297 ft (700 m) Terrain profile Possible remains Center section The plane was made of thin aluminum and unlikely to remain intact after 82 years. Its center section, landing gear, and engines were the heaviest and most durable parts. Engines and propellers MONICA SERRANO AND FERNANDO BAPTISTA, NG STAFF. KAYA BERNE. SOURCE: RICHARD GILLESPIE, THE INTERNATIONAL GROUP FOR HISTORIC AIRCRAFT RECOVERY. Earhart’s custom-built aircraft For her flight around the world in 1937, Amelia Earthart chose one of the most advanced aircraft of her time, the Lockheed Electra 10E. Modifications included additional fuel tanks, an autopilot, and special windows for the navigator. Radio direction finder Aluminum thickness U.S. quarter (for comparison) 0.069” Antenna Navigator's station Thicker part (belly) 0.040” Thinner part (nose, tail) 0.025” Toilet Transmitter Auxiliary battery Transmitter Cloth headliner Foil moisture barrier Aluminum Extra fuel tanks Pratt & Whitney Wasp S3H1 Engine 6 Extra tanks 6 Regular tanks Total capacity 1,151 gallons Navigation aids The engine Earhart's airplane was only the fifth Electra equipped with new and more powerful 550- horsepower engines. The Electra had a radio direction finder coupled to a manually-rotated loop antenna located over the cockpit. Earhart removed the plane's seats to add six fuel tanks, making it necessary to crawl over the tanks to reach the cockpit. Radio problems Reef landing Earhart reported her progress to the Coast Guard cutter Itasca, awaiting her arrival at Howland Island. But she was unable to hear their replies, perhaps due to the loss of an antenna. Some think Earhart landed on the flat reef at Nikumaroro Island during low tide. The plane may have remained there several days before rising tides washed it into the ocean. The plane may have broken up in the surf or floated away to sink in deep water. 38’7’’ Nikumaroro Island 3,281 ft (1,000m) AREA ENLARGED Plane Reef 2,297 ft (700 m) Terrain profile The lost antenna Trailing wire antenna Possible remains On its last takeoff, the plane's ventral antenna suffered damage, a possible cause of the communication failure experienced later. To reduce weight, Earhart removed this antenna used for the international distress frequency. It could be extended 250 feet. The plane was made of thin aluminum and unlikely to remain intact after 82 years. Its center section, landing gear, and engines were the heaviest and most durable parts. Center section Engines and propellers MONICA SERRANO AND FERNANDO BAPTISTA, NG STAFF. KAYA BERNE. SOURCE: RICHARD GILLESPIE, THE INTERNATIONAL GROUP FOR HISTORIC AIRCRAFT RECOVERY. Earhart’s custom-built aircraft For her flight around the world in 1937, Amelia Earthart chose one of the most advanced aircraft of her time, the Lockheed Electra 10E. Modifications included additional fuel tanks, an autopilot, and special windows for the navigator. Aluminum thickness Radio direction finder U.S. quarter (for comparison) 0.069” Antenna Navigator's station Thicker part (belly) 0.040” Thinner part (nose, tail) 0.025” Toilet Auxiliary battery Transmitter Cloth headliner Foil moisture barrier Aluminum Extra fuel tanks Pratt & Whitney Wasp S3H1 Engine 6 Extra tanks 6 Regular tanks Total capacity 1,151 gallons Navigation aids The engine Earhart's airplane was only the fifth Electra equipped with new and more powerful 550- horsepower engines. The Electra had a radio direction finder coupled to a manually-rotated loop antenna located over the cockpit. Earhart removed the plane's seats to add six fuel tanks, making it necessary to crawl over the tanks to reach the cockpit. Radio problems Reef landing Earhart reported her progress to the Coast Guard cutter Itasca, awaiting her arrival at Howland Island. But she was unable to hear their replies, perhaps due to the loss of an antenna. Some think Earhart landed on the flat reef at Nikumaroro Island during low tide. The plane may have remained there several days before rising tides washed it into the ocean. The plane may have broken up in the surf or floated away to sink in deep water. Nikumaroro Island AREA ENLARGED 3,281 ft (1,000m) 38’7’’ Reef Plane 2,297 ft (700 m) Terrain profile Center section The lost antenna Trailing wire antenna Possible remains On its last takeoff, the plane's ventral antenna suffered damage, a possible cause of the communication failure experienced later. To reduce weight, Earhart removed this antenna used for the international distress frequency. It could be extended 250 feet. The plane was made of thin aluminum and unlikely to remain intact after 82 years. Its center section, landing gear, and engines were the heaviest and most durable parts. Engines and propellers MONICA SERRANO AND FERNANDO BAPTISTA, NG STAFF. KAYA BERNE. SOURCE: RICHARD GILLESPIE, THE INTERNATIONAL GROUP FOR HISTORIC AIRCRAFT RECOVERY. Earhart’s custom-built aircraft For her flight around the world in 1937, Amelia Earthart chose one of the most advanced aircraft of her time, the Lockheed Electra 10E. Modifications included additional fuel tanks, an autopilot, and special windows for the navigator. Aluminum thickness U.S. quarter (for comparison) 0.069” Radio direction finder Antenna Thicker part (belly) 0.040” Thinner part (nose, tail) 0.025” Navigator's station Toilet Auxiliary battery Transmitter Cloth headliner Pratt & Whitney Wasp S3H1 Engine Foil moisture barrier Aluminum Extra fuel tanks 6 Extra tanks 6 Regular tanks Total capacity 1,151 gallons Navigation aids The engine Earhart's airplane was only the fifth Electra equipped with new and more powerful 550- horsepower engines. The Electra had a radio direction finder coupled to a manually-rotated loop antenna located over the cockpit. Earhart removed the plane's seats to add six fuel tanks, making it necessary to crawl over the tanks to reach the cockpit. Radio problems Reef landing Earhart reported her progress to the Coast Guard cutter Itasca, awaiting her arrival at Howland Island. But she was unable to hear their replies, perhaps due to the loss of an antenna. Some think Earhart landed on the flat reef at Nikumaroro Island during low tide. The plane may have remained there several days before rising tides washed it into the ocean. The plane may have broken up in the surf or floated away to sink in deep water. Nikumaroro Island AREA ENLARGED 3,281 ft (1,000m) 38’7’’ Reef Plane 2,297 ft (700 m) Terrain profile The lost antenna Trailing wire antenna Possible remains Center section On its last takeoff, the plane's ventral antenna suffered damage, a possible cause of the communication failure experienced later. To reduce weight, Earhart removed this antenna used for the international distress frequency. It could be extended 250 feet. The plane was made of thin aluminum and unlikely to remain intact after 82 years. Its center section, landing gear, and engines were the heaviest and most durable parts. Engines and propellers MONICA SERRANO AND FERNANDO BAPTISTA, NG STAFF. KAYA BERNE. SOURCE: RICHARD GILLESPIE, THE INTERNATIONAL GROUP FOR HISTORIC AIRCRAFT RECOVERY.

When the pilots do spot something, their reactions tend to be muted (unless it’s a charismatic creature such as a dumbo octopus). During a recent watch a tube-shaped metallic object hove into view. The Hercules pilot murmured, “It looks anthropogenic. Should I pick it up?”

The answer was yes. After a moment of hesitation, Hercules stretched out its arm and very slowly closed its pincers around the tube and delicately placed the item into a white storage container on its side.

What was it? The answer would have to wait until the ROVs were recovered and the box could be opened, which wouldn’t be until the next day.

View Images Earhart and navigator Fred Noonan consult a map of the Pacific that shows the planned route of their round-the-world flight. Photograph from Bettmann Archive/Getty images

Spoiler alert: It was not part of Earhart’s plane. Instead, it appeared to be a piece of oceanographic equipment—a sign that other explorers had been here before Ballard.

Ballard shrugs off false alarms, especially this early in the search. “We did this nine days for the Titanic,” he says.