Japan earthquake shifted Earth on its axis
Friday’s magnitude 8.9 earthquake in Japan shifted Earth on its axis and shortened the length of a day by a hair. In the future, scientists said, it will provide an unusually precise view of how Earth is deformed during massive earthquakes at sites where one plate is sliding under another, including the U.S. Pacific Northwest.
The unusually rich detail comes from an extensive network of sensors that were placed at sites across Japan after that country’s Kobe earthquake of 1995, a magnitude 6.8 quake that killed more than 6,000 people because its epicenter was near a major city.