The remote-controlled robot, Packbot, now has its readings from reactors No. 1 and No. 3 at the Fukushima nuclear plant and was scheduled to investigate reactor No. 2 later Monday night. The readings indicate that the environment is still too radioactive for workers to enter.

Packbot is capable of maneuvering through buildings, storing images, measuring radiation levels, and also opening a door at the No. 3 reactor building in Fukushima. The readings are the first in more than a month. Nuclear officials say the readings will not alter TEPCO's roadmap for stabilizing the complex.