A passive satellite developed by the Japan Aerospace Exploration Agency (JAXA) and Kawasaki Heavy Industries that is used in long-range geodetic measurements aimed at rectifying Japan’s geodetic triangular network. The satellite is a hollow sphere, 2.15 m diameter and 685.2 kg mass, covered in 318 mirrors and 120 laser-reflective surfaces. It was launched on 12 August 1986, from Tanegashima Space Center, Japan.