>> this is fantastic. this is the path of the vehicle. the robot is heading in this direction, sending out pings to either side. the side comes and bounces off objects. it is a hard return. a shadow behind it. this is a ship sitting on the bottom and you can see it went over the top of the ship. it leaves a gap beneath the vehicle. why they call it a side scan or side-looking sonar. >> when you get an image like this it is actually two images with the center. >> it is two beams on either side of the vehicle. exactly. port side and starboard side. >> it is not from a plu fin but on a search you were involved. this is actually the "titanic." >> "titanic" split in two. looking at a mile across. these lines here are the path of our vehicles, back and forth, mowing the lawn or plowing. >> i see. you can actually see lines in the image itself. >> exactly right. that is many images. that's a mile across.