Chile earthquake last week has effect the Earth’s rotation and made the length of days on our earth shorter, according a scientist from NASA
Richard Gross, NASA researcher scientist said; The Chile earthquake who is recorded as the seventh strongest earthquake in history has shortened the length of an Earth day about 1.26 milliseconds
“Perhaps more impressive is how much the quake shifted Earth’s axis,” NASA officials said in a Monday update.
Gross and his fellow worker use computer model to measure the aftermath from Chile earthquake, they found that the quake also made Earth’s figure axis moved by around 3 inches or 8 cm or 27 milliseconds
He further said that there is no similarity between the Earth figure axis and north-south axis, that twirls once every day at a speed of about 1,000 mph (1,604 kph).
The figure axis is the axis around which the Earth’s mass is balanced. It is offset from the Earth’s north-south axis by about 33 feet (10 meters).
Strong earthquakes have altered Earth’s days and its axis in the past. The 9.1 Sumatran earthquake in 2004, which set off a deadly tsunami, should have shortened Earth’s days by 6.8 microseconds and shifted its axis by about 2.76 inches (7 cm, or 2.32 milliseconds).
One Earth day is about 24 hours long. Over the course of a year, the length of a day normally changes gradually by one millisecond. It increases in the winter, when the Earth rotates more slowly, and decreases in the summer, Gross has said in the past.
The Chile earthquake was much smaller than the Sumatran temblor, but its effects on the Earth are larger because of its location. Its epicenter was located in the Earth’s mid-latitudes rather than near the equator like the Sumatran event.
The fault responsible for the 2010 Chile quake also slices through Earth at a steeper angle than the Sumatran quake’s fault, NASA scientists said.
“This makes the Chile fault more effective in moving Earth’s mass vertically and hence more effective in shifting Earth’s figure axis,” NASA officials said.
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