Radioactive materials may have sunk 30 cm into ground

TOKYO (Kyodo) -- Radioactive materials released from the crippled Fukushima Daiichi power plant into the atmosphere were found 5 centimeters beneath the ground three months after the breakout of the nuclear crisis last March, but are now believed to have sunk 10 to 30 cm deep, a study by a research institution showed Wednesday.

The hazardous materials must have seeped into the land with rain, according to the Japan Atomic Energy Agency.

"Further delay in decontamination works will make the radioactive materials sink into the ground deeper, and it will impose more burdens on those involved in the decontamination," said Haruo Sato, researcher at the agency's Horonobe Underground Research Center in Hokkaido.

A group of researchers of the agency examined the penetration of four radioactive materials, including cesium 137, at 11 points in Nihonmatsu, Kawamata and Namie in Fukushima Prefecture, which are within a radius 20 to 60-kilometers from the Fukushima complex, in June. Read More

Moon exploration robots tested on sand dunes in Shizuoka Prefecture, Japan

HAMAMATSU, Shizuoka -- The Japan Aerospace Exploration Agency (JAXA) has conducted tests of prototype moon exploration robots here, that were designed by several institutions to become part of Japan's next-generation lunar exploratory equipment.

On March 13, the agency conducted test runs on a total of eight robot prototypes at the Nakatajima sand dunes in Hamamatsu, Shizuoka Prefecture, a vast undulated land area somewhat resembling the moon's surface.

The eight robot prototypes were made by various research institutions, including Tohoku University, the Aichi University of Technology, Osaka University and Tokyu Construction, which are competing in JAXA's Lunar Robotics Challenge for designing robots to explore the moon's surface.

During the experimental run, the agency tested the robots' drivability and collected various data related to their performance.

Seeking to capitalize on their success with the SELENE (Selenological and Engineering Explorer), a lunar orbiter better known by its nickname Kaguya, JAXA is now looking into the development of next-generation moon exploratory equipment.

The Kaguya probe, after successfully orbiting the moon for approximately a year and nine months from September 2007, ended its mission and was crashed onto the lunar surface in June 2009. Read More

Strong quakes rattle Tokyo, northeast Japan

TOKYO (AP) -- A series of earthquakes rattled Tokyo and northeast Japan late Wednesday evening but caused no apparent damage or injury in the same region hit by last year's devastating tsunami.

The strongest tremor, off Hokkaido, had a magnitude of 6.8 and caused tidal changes that prompted some communities to issue evacuation orders or tsunami advisories to residents nearest the coast.

A swelling of 20 centimeters was observed in the port of Hachinohe in Aomori, northern Japan, about one hour later. Smaller changes were reported in several locations in Hokkaido and Aomori Prefecture.

The Japan Meteorological Agency lifted all tsunami advisories about an hour and half later.

The earthquake felt in Tokyo was magnitude 6.1 and centered just off the coast of Chiba, east of Tokyo, at a rather shallow 10 kilometers below the sea surface. Read More