This view of Earth comes from NASA's Moderate Resolution Imaging Spectroradiometer aboard the Terra satellite.
The Feb. 27 magnitude 8.8 earthquake in Chile may have shortened the length of each Earth day.
JPL research scientist Richard Gross computed how Earth's rotation should have changed as a result of the Feb. 27 quake. Using a complex model, he and fellow scientists came up with a preliminary calculation that the quake should have shortened the length of an Earth day by about 1.26 microseconds (a microsecond is one millionth of a second).
Perhaps more impressive is how much the quake shifted Earth's axis. Gross calculates the quake should have moved Earth's figure axis (the axis about which Earth's mass is balanced) by 2.7 milliarcseconds (about 8 centimeters, or 3 inches). Earth's figure axis is not the same as its north-south axis; they are offset by about 10 meters (about 33 feet).
By comparison, Gross said the same model estimated the 2004 magnitude 9.1 Sumatran earthquake should have shortened the length of day by 6.8 microseconds and shifted Earth's axis by 2.32 milliarcseconds (about 7 centimeters, or 2.76 inches).
Gross said that even though the Chilean earthquake is much smaller than the Sumatran quake, it is predicted to have changed the position of the figure axis by a bit more for two reasons. First, unlike the 2004 Sumatran earthquake, which was located near the equator, the 2010 Chilean earthquake was located in Earth's mid-latitudes, which makes it more effective in shifting Earth's figure axis. Second, the fault responsible for the 2010 Chiliean earthquake dips into Earth at a slightly steeper angle than does the fault responsible for the 2004 Sumatran earthquake. This makes the Chile fault more effective in moving Earth's mass vertically and hence more effective in shifting Earth's figure axis.
Gross said the Chile predictions will likely change as data on the quake are further refined.
The Feb. 27 magnitude 8.8 earthquake in Chile may have shortened the length of each Earth day.
JPL research scientist Richard Gross computed how Earth's rotation should have changed as a result of the Feb. 27 quake. Using a complex model, he and fellow scientists came up with a preliminary calculation that the quake should have shortened the length of an Earth day by about 1.26 microseconds (a microsecond is one millionth of a second).
Perhaps more impressive is how much the quake shifted Earth's axis. Gross calculates the quake should have moved Earth's figure axis (the axis about which Earth's mass is balanced) by 2.7 milliarcseconds (about 8 centimeters, or 3 inches). Earth's figure axis is not the same as its north-south axis; they are offset by about 10 meters (about 33 feet).
By comparison, Gross said the same model estimated the 2004 magnitude 9.1 Sumatran earthquake should have shortened the length of day by 6.8 microseconds and shifted Earth's axis by 2.32 milliarcseconds (about 7 centimeters, or 2.76 inches).
Gross said that even though the Chilean earthquake is much smaller than the Sumatran quake, it is predicted to have changed the position of the figure axis by a bit more for two reasons. First, unlike the 2004 Sumatran earthquake, which was located near the equator, the 2010 Chilean earthquake was located in Earth's mid-latitudes, which makes it more effective in shifting Earth's figure axis. Second, the fault responsible for the 2010 Chiliean earthquake dips into Earth at a slightly steeper angle than does the fault responsible for the 2004 Sumatran earthquake. This makes the Chile fault more effective in moving Earth's mass vertically and hence more effective in shifting Earth's figure axis.
Gross said the Chile predictions will likely change as data on the quake are further refined.
Do you like this article? Share It!
0 comments to "Chilean Quake May Have Shortened Earth Days"
Popular Posts
-
NASA is providing up to $20 million over the next five years to support a national program to inspire student interest in science, technolo...
-
Even though there are many advancement in technology, keeping foods fresher in space for a long period has been impossible. Research has b...
-
Though the sun's brightness was once thought to be constant, NASA has launched a series of satellite instruments that have helpe...
-
NASA technologists will get a opportunity next summer time to experience the good old days when Organization technical engineers would conn... -
X-24B Precision Landings Proved That Shuttle Could Land Unpowered NASA research pilot John Manke worked through his prelaunch checklist wh... -
The mars rock touches the NASA curiosity this time it touches the more different from before Tasks. The mars rock is looks like some odd... -
Leaner, greener flying machines for the year 2025 are on the drawing boards of three industry teams under contract to the NASA Aeronautics ... -
Images from NASA's Wide-field Infrared Survey Explorer (WISE) reveal an old star in the throes of a fiery outburst, spraying the cosm... -
The argument that the moon is a dry, desolate place no longer holds water. Secrets the moon has been holding, for perhaps billions of years,...
