In 1996, NASA sank a 132-foot shuttle booster training device off Port Canaveral to become an artificial reef; marine life was expected to establish itself there within four months

In 1996, a retired piece of NASA's Space Shuttle training equipment found an unusual second life. Instead of being scrapped or left on land, the 132-foot structure was sunk on purpose in the Atlantic Ocean to become an artificial reef. The object was an obsolete Solid Rocket Booster recovery training device called the Ocean Training Fixture, or OTF, according to a news release from NASA's Kennedy Space Center, issued six days after the sinking, on April 17, 1996.

A space training device heads underwater

The OTF was used to train divers for recovering the Space Shuttle's two Solid Rocket Boosters from the Atlantic after launches. By 1996, NASA said the OTF no longer served any useful purpose for land-based training. On April 11, 1996, NASA's recovery ship Liberty Star towed the 132-foot-long OTF to an area 22 miles southeast of Port Canaveral, Florida. It was then disposed of using six charges in 122 feet of water, the agency's release detailed.


The OTF was repurposed as part of an artificial reef project. The agency explained that the OTF was meant to be a key component of an artificial reef, where there would be conditions favorable to marine organisms. In addition, the Canaveral Port Authority had been working on such a reef construction project since 1994 by sinking four railway cars into the same spot. NASA also said it planned to add more retired space hardware, including parts from the Apollo era.

It was designed to become a new underwater habitat

Artificial reefs can provide structure in areas where the surrounding seafloor offers little three-dimensional habitat. Research off southeastern Florida shows that fish communities can begin using such structures quickly. In the peer-reviewed study, "Effects of Reef Size on Colonization and Assemblage Structure of Fishes at Artificial Reefs Off Southeastern Florida, U.S.A.," James A. Bohnsack, Douglas E. Harper, David B. McClellan and Mark Hulsbeck studied 16 artificial reefs made from concrete modules. The researchers reported that colonization was rapid and that artificial reefs supported diverse and abundant fish communities. They also found that the size of the reef affected the number of species, individual fish, and biomass associated with the reefs. The study was not of the artificial reef built from the OTF, later named the Thomas William Hart Reef, so the results cannot be used to say exactly how the NASA structure formed, but it does offer useful scientific context for why adding a large structure onto the seafloor can create habitat for marine life.

The four-month timeline was an expectation

NASA said in 1996 that it expected marine life to establish on the reef in about four months. That prediction should not be read as confirmation that the reef was established four months later. Other research from a separate Florida artificial reef project also indicates why marine communities should not be viewed as static. In the peer-reviewed paper "Fish assemblages associated with artificial reefs of concrete aggregates or quarry stone offshore Miami Beach, Florida, USA," Brian K. Walker, Bruce Henderson, and Richard E. Spieler compared fish communities around different artificial reef materials. The study looked at 12 reefs off Miami Beach and found differences in fish communities among the reef types, demonstrating that the material and structure of an artificial reef can matter. The researchers followed the reefs every two months from October 1998 to February 2001, recording fish species, abundance and length, plus spiny lobster abundance with SCUBA surveys. In all, they documented 146 fish species, found strong seasonal swings with summer peaks and winter lows, and reported no significant differences in fish abundance, richness, or biomass among the three reef materials.

A reef with a NASA connection

The OTF reef would serve more than one purpose, the agency noted. Its site was opened to recreational divers and fishermen, while NASA divers were to use part of the reef for certification exercises. The site was also named for a personal link to the Space Shuttle recovery program. The reef was named the Thomas William Hart Reef on navigational charts after Thomas William Hart, a recently deceased former diver on a Solid Rocket Booster recovery team. A plaque affixed to the front of the OTF serves as a memorial. The result was an unusual transition for a piece of space hardware.