MOBILE OBJECT CONTROL DEVICE, MOBILE OBJECT CONTROL METHOD, AND PROGRAM

Provided is a mobile object control device configured to: recognize a surrounding situation of a mobile object; set, based on the recognized surrounding situation, a risk area in which positions of the surrounding situation are associated with risk values that are indicator values indicating degrees to which the mobile object is to avoid traveling; generate a target trajectory indicating a route along which the mobile object is to travel in future; cause the mobile object to travel along the generated target trajectory; and set at least one observation point in each of three or more provisional trajectories branching at a specific location ahead of the mobile object, and generate the target trajectory based on the risk area and the at least one observation point.