Japan observed a national moment of silence Thursday at 2:46 p.m., exactly a decade after a devastating earthquake and tsunami rocked the eastern part of the country and triggered the one of the world's worst nuclear disasters.

The magnitude 9.0 quake was the largest ever to strike the quake-prone nation. The tsunami it triggered drove a surge of water as high as 90 feet in some areas, washing away entire towns along Japan's northeast coast.

The catastrophe killed 18,000 people and left almost 500,000 homeless. Nearly 4,000 more people died later from illness and stress-induced suicide. More than 40,000 people still have not returned to their hometowns.

Debris was swept as far away as Hawaii, 4,000 miles to the east. Small amounts of radiation reached California years later.