Tokyo has been operating spy satellites for four years that have not been registered with the United Nations, despite having signed an international treaty that requires it to report them.
The Convention on Registration of Objects launched into Outer Space, adopted in 1974 and proclaimed in 1976, required signatories to identify the artificial satellites and other objects they put in space. Japan signed that treaty in 1983. Treaty violations are not subject to punishment.
"We cannot make detailed information public because of security," said an official of the Cabinet Satellite Intelligence Center, which owns the satellites. "Besides, there are many European and U.S. military satellites that are unregistered."