Olympic-class ocean liner
When "Titanic" sank in 1912 and "Britannic" sank in 1916, their sinkings did not receive the same attention, due to the death toll (1,517 on "Titanic" and 30 on "Britannic"). Because the exact position of the sinking of the "Britannic" is known and the location is shallow, the wreck was discovered relatively easily in 1975. "Titanic", however, drew everyone's attention in 1912. After several attempts, the wreck was finally located by Jean-Louis Michel of Ifremer and Robert Ballard following a top secret mission for the US Navy to investigate the wreckage of two nuclear submarines, USS Thresher (SSN-593) and the USS Scorpion (SSN-589), that sank in the North Atlantic in the 1960s. The discovery of the wreck occurred on 1 September 1985, at 25 kilometres from the position given of the sinking. The wreck lies about 4,000 metres deep, broken in two. The bow is relatively well preserved, but the stern partially imploded, and to a large extent disintegrated during the descent and impact on the seabed.
Wreck of the RMS Titanic
The most dramatic deterioration has been caused by biological factors. It used to be thought that the depths of the ocean were a lifeless desert, but research carried out since the mid-1980s has found that the ocean floor is teeming with life and may rival the tropical rainforests for biodiversity. During the 1991 IMAX expedition, scientists were surprised by the variety of organisms that they found in and around "Titanic". A total of 28 species were observed, including sea anemones, crabs, shrimp, starfish, and rattail fish up to a yard (1 m) long. Much larger creatures have been glimpsed by explorers. Some of "Titanic"s fauna has never been seen anywhere else; James Cameron's 2001 expedition discovered a previously unknown type of sea cucumber, lavender with a glowing row of phosphorescent "portholes" along its side. A newly discovered species of rust-eating bacterium found on the ship has been named "Halomonas titanicae", which has been found to cause rapid decay of the wreck. Henrietta Mann, who discovered the bacteria, has estimated that the "Titanic" will completely collapse possibly as soon as 2025. The Canadian geophysicist Steve Blasco has commented that the wreck "has become an oasis, a thriving ecosystem sitting in a vast desert". In mid 2016, the facilities of the Institut Laue-Langevin 
used neutron imaging to demonstrate that a molecule called ectoine is used by "Halomonas titanicae" to regulate fluid balance and cell volume to survive at such pressures and salinities. Analysis by Henrietta Mann and Bhavleen Kaur, both of Dalhousie University in Halifax, Nova Scotia, in conjunction with other scientists and researchers of the University of Seville in Spain, has determined that the wreck of "Titanic" will not exist by 2037 and that preservation of "Titanic" is impossible. "Unfortunately, because Titanic is 2.3 miles down, it is very difficult or impossible to preserve. It is film which will preserve it for history now," says Mann. "It has already lasted for 100 years, but eventually there will be nothing left but a rust stain on the bottom of the Atlantic... I think Titanic has maybe 15 or 20 years left. I don't think it will have too much longer than that." Other scientists have estimated that "Titanic" will last no longer than 14 years, as of 2017.