TOKYO — The Japan Aerospace Exploration Agency (JAXA) will use a Ukrainian Dnepr rocket to launch a long-delayed experimental laser communications satellite this summer, according to documents released Dec. 27 by Japan’s Space Activities Commission .

The Optical Inter-orbit Communications Engineering Test Satellite (OICETS) was built by NEC Corp., now NEC Toshiba Space Systems Ltd., Yokohama, in the late 1990s.

OICETS was designed to test laser communications links between its own low Earth orbit and the geostationary orbit location of the European Space Agency’s Artemis satellite.

The OICETS flight was postponed after Artemis was deposited in the wrong orbit during a July 2001 launch aboard an Ariane 5 rocket. Artemis reached geostationary orbit using its onboard fuel in January 2003.

According to the documents , JAXA will reactivate launch preparations for OICETS and will use the Dnepr rocket because there is no suitable Japanese alternative .

The price of the launch and other contract details were not disclosed.

OICETS needs to be launched this summer if it is to have enough time to conduct its communications experiments with Artemis before the European satellite reaches the end of its expected service life, according to the Space Activities Commission.

The commission announcement report outlined a number of reasons why JAXA could not use a Japanese launcher.

The report noted that there are no H2A launchers available to launch OICETS this summer, and another launcher, the Mu-5, is unsuitable because the satellite was not configured to cope with that vehicle’s the high acceleration .

The planned U.S.-Japanese rocket also will not be ready on time, according to the report.

The Dnepr launch vehicle is based on the SS-18 intercontinental ballistic missile developed by the Soviet Union. It was designed by the Yushnoye State Design Office of Dnepropetrovsk, Ukraine, and is marketed by Moscow-based International Space Company Kosmotras. Dnepr vehicles are launched from Baikonur Cosmodrome in Kazakhstan.