Coordinates, and the fact that they know the exact layout of the ship, among other things.
"Keeping her location a secret, Bob Ballard used GPS to find the Titanic again when he returned the next year. He hoped to prevent treasure seekers from finding her and plundering the ship for booty such as coffee cups inscribed with RMS Titanic."
From above link.
I don't know that the name is still on the ship- it has been underwater rusting for nearly 96 years now. I tried to find that out, but couldn't.
gsngirl7 answered Wednesday December 5 2007, 9:52 pm: Yes the ship that they found was the Titanic. They were able to identify the ship by the name on it's side and recover objects from the ship. They were able to prove it to by the way it was broken in two. Hope my advice helps! ♥ Jenny [ gsngirl7's advice column | Ask gsngirl7 A Question ]
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