Group to revisit Earhart mystery     (copy)

This undated file photo shows Amelia Earhart, the first woman to fly solo across the Atlantic Ocean.

If you’ve ever searched the house for car keys or scoured a backyard for a missing wedding ring, the immensity of Robert Ballard’s task comes into focus.

A wheel or a piece of sheet metal might seem hard to miss, but the Pacific Ocean’s massive size makes the search for Amelia Earhart’s plane a thousand times harder than any needle in a haystack.

The Pacific Ocean covers 60 million square miles — larger than the landmass of all the continents combined. It extends to an average depth of 13,000 feet, including 36,000 feet in one spot.

Somewhere in this vastness lies the answer to an enduring question that is of no small consequence in these parts: What happened to Earhart and her navigator, Fred Noonan? They were last seen on July 2, 1937, as their Lockheed Electra 10e aircraft took off for Howland Island, a speck some 2,556 miles away.

The disappearance of Earhart, who was born in Atchison, Kansas, spawned decades of theories and speculation about crashing into the ocean, surviving for a short time on a small island or reef or even being captured by the Japanese as tensions started to build in the years before World War II.

Ballard zeroed his search on the four-and-a-half-mile-long Pacific island of Nikumaroro on the theory that Earhart crash landed there or on a nearby reef. Some of the past clues found on Nikumaroro include a jar of freckle cream, a mysterious piece of sheet metal and human bones that could be subject to additional testing.

Details from Ballard’s latest quest were unveiled Sunday night in a special program, “Expedition Amelia,” on the National Geographic Channel. The TV program did not reveal any new physical evidence of Earhart’s plane, but it offered a compelling summary of why Nikumaroro is a possible key to this mystery. It also ended with a tantalizing hint that testing on bone fragments could advance knowledge on Earhart’s fate.

So the search continues, and if anyone can find out what happened to Amelia Earhart, Ballard would seem the ideal choice for this effort.

The deep-sea explorer famously uncovered the Titanic in 1985, leading to a renewed fascination with that doomed ship. Ballard’s other deep-sea discoveries include the German battleship Bismarck in 1989 and the missing patrol boat PT-109 that John F. Kennedy commanded during World War II.

More than anything, this latest search reminds us why Earhart’s pioneering and adventurous life continues to hold us in sway.

The Pacific Ocean still conceals the answer to what happened to this well-known native of Atchison. Ballard may yet unlock it, but until then the mystery remains part of the allure.