The was developed by the Avionics and Supersonic Aerodynamics (AVSA) research group in the early days of the Japanese space program. A prominent engineer on the project was Hideo Itokawa. The rocket was first launched on 12 April 1955. The dimensions were 23 cm in length by 1.8 cm in diameter, weighing 200 grams. Bibliography External links Space program of Japan Japanese inventions