Secretary of State Hillary Rodham Clinton is offering her support and encouragement to a privately financed effort to find the final resting place of famed 20th-century aviator Amelia Earhart.


Earhart, the first woman to fly solo across the Atlantic Ocean, disappeared over the Pacific Ocean in 1937 during an attempt to circumnavigate the globe.


"We can be as optimistic and even audacious as Amelia Earhart," Clinton said Tuesday. "There is great honor and possibility in the search itself."


The search is being conducted by The International Group for Historic Aircraft Recovery (TIGHAR), which says it believes Earhart and her navigator, Fred Noonan, crash-landed on the remote Pacific island of Nikumaroro after they disappeared on July 2, 1937. The $500,000 expedition will coincide with the 75th anniversary of their disappearance. The State Department will provide limited logistical support for the quest.


Nikumaroro, also known as Gardner Island, is a coral atoll 3.7 miles long and 1.2 miles wide surrounding a central lagoon. The uninhabited island, which was once claimed by the United Kingdom, is currently part of the Republic of Kiribati, a tiny Micronesian nation comprised of one main island and 31 other atolls.


Theories abound regarding Earhart's disappearance. Some historians believe she crashed into the ocean, but recent analysis of a photograph taken at Nikumaroro in late 1937 show, according to TIGHAR, what appears to be a wheel of a plane sticking up out of the water.


Bone fragments found on Nikumaroro in 2010 have been said by some to belong to either Earhart or Noonan. Some historians believe they could have survived on the island for up to a week after the crash. The island has abundant fish but little fresh water.


TIGHAR's executive director acknowledged that the evidence is "circumstantial," but called Earhart's disappearance "the last great American mystery of the 20th century."


At the time of the crash, Earhart was one of the most famous women in the world — a role model for a world recovering from the Great Depression.


"Amelia Earhart may have been a unlikely heroine for a nation down on its luck," Clinton said, "but she embodies the spirit of an America coming of age and increasingly confident, ready to lead in a quite uncertain and dangerous world. She gave people hope and she inspired them to dream bigger and bolder."


Clinton said that Earhart is still relevant today, three-quarters of a century after her disappearance. "After a long decade of war, terrorism and recession, there are some who are asking whether we still have what it takes to lead, and like that earlier generation, we too could use some of Amelia's spirit."


According to the Official Amelia Earhart website, the 1937 search for the aviatrix was one of the most extensive in history, costing $4 million and covering 250,000 square miles of ocean. It was called off after 17 days, on July 19, 1937.