Abstract: A spacecraft for changing an orbit or an attitude of a target in outer space by irradiating the target with a laser, the spacecraft includes: a laser apparatus configured to generate the laser; a focusing unit configured to converge the laser; a detecting unit configured to acquire detection information including a distance between the spacecraft and the target; and an irradiation control unit configured to control the focusing unit on the basis of the distance so that the laser converges on the target.

Abstract: A propulsion strengthening member attached to a surface of an object existing in outer space, the propulsion strengthening member includes: a transparent member that transmits an emitted laser; and an opaque member that is provided between the transparent member and the object and absorbs the laser such that at least a part thereof is evaporated by energy of the laser.