A US research expedition searching for Amelia Earhart's missing aircraft returned without a breakthrough after examining a suspicious object on Nikumaroro, an uninhabited Pacific atoll in Kiribati.
Purdue University said the object was likely a collection of large trees washed ashore, closing hopes that the find could explain the aviator's fate.
The 17-member team traveled to the remote island after reviewing satellite imagery and aerial footage that appeared to show a metallic reflection in shallow waters near the Taraia Peninsula.
Researchers spent four days conducting investigations, including metal detection, after reaching the coral-ringed atoll following a multiday sea voyage and weather-related delays.
Steve Schultz of Purdue University, which helped support the mission, acknowledged the team had not found conclusive evidence of the missing aircraft.
"Unfortunately, we weren't able to find that smoking gun," Schultz said.
How the Reflection Was Explained
The suspected debris first drew attention through satellite images captured in 2020.
Richard Pettigrew, head of the nonprofit Archaeological Legacy Institute, examined additional imagery, including aerial video, and believed a reflection on the water could indicate a metallic object.
Other researchers who had investigated Earhart's disappearance had previously identified the shape as a fallen tree.
Purdue said its examination indicated the object was probably a natural accumulation of trees deposited along a sandy outcrop.
The reflective appearance that had prompted speculation about aircraft debris also had a geological explanation.
According to the university, a carbonate coating on the fragment produced the metallic-looking surface.
Researchers also found other objects covered with a shiny, hardened mixture of coral sand, offering further context for the misleading visual appearance.
The university described the expedition's findings as a setback but said the work contributed to the continuing investigation into Earhart's disappearance.
"While we know this is disappointing to many, including us, this mission adds a new chapter in the quest to find the ultimate answer to the mystery of what happened to Earhart during her attempt to circumnavigate the globe nearly nine decades ago," the university statement said.
Nikumaroro has remained a significant location in the search because researchers have considered it a possible landing site following the disappearance of Earhart and her navigator, Fred Noonan, in 1937.
The pair vanished while attempting to fly around the world near the equator, triggering one of history's largest air and sea searches.
Previous expeditions to the uninhabited atoll uncovered items that investigators associated with a possible castaway site, including a woman's shoe believed to date from the 1930s and glass from a jar of freckle cream.
Those discoveries have fueled speculation but have not conclusively established what happened to the missing aviators.
Purdue University in Indiana had a historical connection to Earhart, who taught there and mentored young female pilots.
The institution also helped finance her modified Lockheed Electra 10-E, an aircraft she referred to as her flying laboratory.
The latest findings add to the list of unconfirmed explanations for Earhart's disappearance.
Other theories have suggested that Japanese forces captured her or that she survived and lived under an assumed identity.
Earhart, who became the first woman to complete a nonstop solo transatlantic flight, remains one of aviation history's most prominent missing figures.
