Wreck of the RMS Titanic research. The stern section, which had previously received relatively little attention from explorers, was specifically targeted for analysis. The microbial colonies aboard "Titanic" were also a key focus of investigation. The second expedition, from 27 May – 12 June 2004, saw the return of Robert Ballard to "Titanic" nearly 20 years after he discovered it. The expedition spent 11 days on the wreck, carrying out high-resolution mapping using video and stereoscopic still images. 2005 saw two expeditions to the "Titanic". James Cameron returned for the third and last time to film "Last Mysteries of the Titanic". Another expedition searched for
Wreck of the RMS Titanic than liquid water, would float to the surface and could be towed to shore. The BOC Group calculated that this would require half a million tons of liquid nitrogen to be pumped down to the sea bed. In his 1976 thriller "Raise the Titanic!", author Clive Cussler's hero Dirk Pitt repairs the holes in "Titanic"s hull, pumps it full of compressed air and succeeds in making it "leap out of the waves like a modern submarine blowing its ballast tanks", a scene depicted on the posters of the subsequent film of the book. Although this was an "artistically stimulating" highlight