SOUTH PORTLAND, Maine (AP) — An expedition team using sonar imaging and robots has created what's believed to be the first comprehensive map of the entire Titanic wreck site.

The map shows where hundreds of objects and pieces of the ship landed, and provides new evidence on what happened when the supposedly unsinkable ship violently ripped apart on its maiden voyage 100 years ago.

Details are not being released yet. But researchers tell The Associated Press that the map suggests, for instance, that the stern rotated like a helicopter blade as the ship sank instead of plunging straight down.

The mapping took place during a 2010 scientific expedition to the wreck site. The History channel is airing a documentary on the expedition and the map on April 15. That's the anniversary of the sinking.