KEY LARGO -- In 1962, seven years before astronaut Neil Armstrong stepped on the moon, Albert Falco and Claude Wesly captured the world’s imagination by becoming the first humans to live under the sea in a strange steel cylinder developed by Jacques Cousteau.

Conshelf I, heralded as the world’s first underwater habitat, was basically a big yellow oil drum with a hole in the bottom — but it had the comforts of home with a TV, radio, library and bed. For one week, Falco and Wesly lived and worked 33 feet under the sea off the coast of Marseilles, France.

The mysterious deep blue oceans became more exciting and more inviting, beginning a new era of exploration and research. Soon, more than 60 underwater habitats from 17 countries would take the plunge, including the U.S. Navy’s SEALAB, the General Electric-developed Tektite, the U.S. government’s Hydrolab and La Chalupa Research Laboratory — developed by ocean explorer and entrepreneur Ian Koblick, who lives in Key Largo.

But over the decades, the excitement for offshore underwater research habitats died down as the money dried up. Today, there is just one operating in the world: Aquarius, anchored for the past 20 years in waters 3½ miles off the shore of Key Largo.

By the end of this year, there could be none.

“It’s a bit disheartening that Aquarius could go away — the last underwater habitat,” said Craig Cooper, who retired two years ago after 19 years as Aquarius’ operations director. “When I was young, I thought we’d all be living down in the sea in condos. But I found out the ocean is a tougher place than it looks to be from the surface.”

In its proposed $5 billion 2013 budget, the National Oceanic and Atmospheric Administration, which owns Aquarius, has called for termination of the one-of-a-kind reef base program despite its minimal operating cost of $1.2 to $3 million.

“That amount is what people at the Pentagon call decimal dust — a number way too small its past the decimal point in the budget,” said Mark Patterson, professor of marine science at the College of William and Mary. “For that little amount, it could be the end of an era.

“But we all hope not,” he added. “Aquarius is too valuable to lose.”

Leading the battle in Washington is U.S. Rep. Ileana Ros-Lehtinen, who represents the Keys and has made four dives to Aquarius. She and fellow Congress members Mario Diaz-Balart and David Rivera took a boat ride out to Aquarius in mid-July, applauding the aquanauts when they finished their long decompression after a week living in the sea.

“There is no other underwater facility like it,” Ros-Lehtinen said in a phone call from Washington. “It deserves our support.”

The three Congress members will meet Wednesday in Washington with NOAA’s head, Jane Lubchenco, to urge her to divert $2 million to fund Aquarius for next year.

Lubchenco, who SCUBA dived a reef in Key Largo two years ago for a pioneering coral reef restoration project, said in a statement that the Aquarius program has been a “vital part” of ocean research, “but unfortunately our budget environment is very, very challenging and we are unable to do all that we would like.”

Renowned ocean explorer and former NOAA chief scientist Sylvia Earle, known as “Her Deepness,” called the decision to end the underwater research program “stupid.”