Astronaut Satoshi Furukawa had a bird's eye view of Tohoku's reconstruction efforts from the International Space Station and said he was happy he could help them in his own small way as the effort took hold.

"Light was gradually increasing and I felt the warmth of human activities," Furukawa, 47, told reporters Wednesday night via a teleconference from Houston.

"I had an opportunity (from space) to communicate with children and I would be happy if that offered some encouragement to them no matter how small," he said.