Chilean Earthquake Shortened Day, Knocked Earth Off Its Axis

The 8.8 magnitude Chilean earthquake was so strong that it literally knocked the earth off its axis – permanently. Richard Gross, a research scientist at NASA’s Jet Propulsion Lab, calculated that the earth’s rotation changed so that the length of our day is now roughly 1.26 microseconds shorter.  A microsecond is equivalent to one millionth of a second.  The Chilean quake also shifted earth’s figure axis (the axis on which our planet’s mass is balanced) by three inches.

By contrast, the 9.1 magnitude 2004 Sumatran earthquake shifted the earth’s axis by 2.76 inches and made the day shorter by 6.8 microseconds.  The larger shift in the earth’s axis as the result of a slightly smaller earthquake is because the Chilean trembler occurred in the earth’s mid-latitudes.  The fault responsible for Chile’s quake also cuts more deeply into the earth and at a steeper angle than in Sumatra.  Haiti’s 7.0 January earthquake, which occurred close to the surface, had no impact on the earth’s rotation.