The Japan Aerospace Exploration Agency successfully launched an optical communications test satellite and a piggyback satellite from a launch site in Kazakstan early Wednesday Japan time.

The Optical Inter-orbit Communication Engineering Test Satellite and the Innovative Technology Demonstration Experiment Satellite separated from the Ukrainian-made Dnepr rocket about 15 minutes after liftoff from Baikonur Cosmodrome and entered orbit at an altitude of about 610 km, JAXA said.

The OICETS mission is the world's first optical intercommunications experiment between a geostationary satellite and a low-Earth-orbit satellite. It is aimed at developing new technologies to improve data transmission rates and capacities in future space activities.

After the liftoff, the agency detected problems with some of the positioning sensors on the OICETS, nicknamed Kirari, and in a subsystem for the precise measurement of the distance from Earth.

Officials said the malfunctions won't affect the satellite's positioning control, but the agency is investigating whether it could pose problems for planned experiments.

The main planned in-orbit experiments include testing high-precision acquisition and tracking technologies, optical interorbit communication, and optical components and studying satellite microvibrations.

Kirari, which means "gleam" in Japanese, cost 12.7 billion yen to develop and the piggyback satellite, known as INDEX, cost about 400 million yen. JAXA commissioned a private Ukrainian company for the launch at a cost of some 1 billion yen.