Reflector, deployable antenna, and spacecraft

A reflector, comprising:

• a hub having a cross section formed in a circular, elliptical or polygonal shape;
• a plurality of ribs, each of which has an inner side surface facing an outer peripheral side of the hub when folded, and an outer side surface that is a surface opposite to the inner side surface, the plurality of ribs being folded so as to be wound around an outer periphery of the hub such that the inner side surface of each rib and the outer side surface of its adjacent rib partially face each other or the outer side surface of each rib and the inner side surface of its adjacent rib partially face each other, each rib being deployed in a parabolic shape from a bottom end connected to the hub toward a tip end located opposite to the bottom end;
• and
• a sheet installed across each of the plurality of ribs and capable of reflecting radio waves;
• wherein each of the plurality of ribs is formed of at least two flat plates which face each other;
• and
• wherein each of the plurality of ribs includes a plurality of restricting members disposed between the two flat plates at predetermined intervals between the bottom end and the tip end.