HOUSTON (Kyodo) Astronaut Koichi Wakata has reported a problem with the robotic arm on the International Space Station, according to fellow astronaut Satoshi Furukawa, who is observing the mission from Earth.

Wakata, on his second day aboard the ISS, was operating the robotic arm to bring aboard large solar power generation equipment that had been unloaded from the space shuttle Discovery by other astronauts, Furukawa said.

Wakata reported to ground control that a camera on the shuttle showed that wires on the robotic arm were in the wrong position. The control center sent an instruction to crew members, who fixed the problem, Furukawa said.

Earlier Wednesday, Wakata transferred kidney and liver cells taken from frogs to an experiment unit in the Kibo laboratory module, Japanese scientists said.

The cells will be used in an experiment proposed by Makoto Asashima, a biologist and executive vice president of the University of Tokyo.

The experiment unit will be run by remote control from the Japan Aerospace Exploration Agency's Tsukuba Space Center in Ibaraki Prefecture.

The cells, which will be frozen after about 10 days of cultivation, will be carried back to Earth by Wakata, the scientists said.

Wakata was one of seven crew members aboard the Discovery, which lifted off Sunday from the Kennedy Space Center in Florida. He is scheduled to return to Earth at the end of June on a U.S. shuttle after completing assembly of the Kibo module.