The earthquake in Japan devastated a country, but it also had a geological effect on the earth, changing the length of our days. According to physicists at NASA’s Jet Propulsion Laboratory, last week’s earthquake actually resulted in our days being shortened by 1.8 microseconds. Dr. Jean Dickey, a physicist with NASA’s Jet Propulsion Laboratory explains that the mass of the earth changed in such a way that the rotation changed. However, she says that the days change fairly often following atmospheric changes and that, while the earthquake had a devastating effect on Japan, the length of the day is not something to be concerned about.