Abstract: A spacecraft includes: an ejector that ejects an object being a base of a shooting star at a speed of 120 m/s or more; a direction controller that controls a direction in which the object is ejected; and a position controller that controls a position at which the object is ejected. The ejector sequentially ejects objects at a predetermined time interval. The ejector controls a time interval individually for each of the objects. The spacecraft includes an autonomous controller that autonomously controls the ejector, direction controller, and position controller, to eject the object in a predetermined ejecting direction and at predetermined ejecting position and speed. The autonomous controller controls ejection of the object based on a result of determination on measurement data individually performed by each of arithmetic units.