Will Titanic vanish right before our eyes?

>>> almost a century after it went down in the north atlantic , our fascination with the " titantic " endures. now there's a new twist and a new danger to the " titantic ." a natural predator if you will that threatens the old ship wednesday begun. nbc's kerry sanders recently traveled to the site of the " titantic " has more for us tonight.

>> reporter: in the north atlantic two miles below the sea the so-called unsinkable " titantic " rests in darkness. the water temperature a cool 29 degrees. since the wreckage was first discovered in 1985 scientific teams have wonldz erred could the 99-year-old graveyard one day turn to dust? now experts at the university in halif halifax, canada have concluded a unique species of microscopic bacteria is eating away at the titantic . the bacteria consume iron creating so-called rusticles. it's devouring the debris here faster than ever seen on a wreck before.

>> it's getting beaten up by currents in the deep sea , but also there's bacteria, actually microbial colonies eating away at the hull.

>> reporter: the cable from the remotely operated vehicle accidentally snagged the ship's railing. scientists say those crusty trails and the dust you see kicking up there is what the bacteria leaves behind after eating.

>> part of what i'm hearing this time that shocks me is in 20 or 25 years we may start to see the decks of titantic collapsing.

>> reporter: because the pictures are so stunning, people may not realize 40% of debris field remains mostly undocumented and unstudied. the first mapping of the area just took place five months ago.

>> iceberg straight ahead.

>> reporter: experts say the movie only tells one version why it sank. it may be the iceberg collapsed at the hull plating flooding the lower deck. but another popular theory is the iceberg caused rivets to pop allowing a whole section of the hull to give way. the unsinkable titantic now with the new foe. kerry sanders , nbc news, miami.