Tags: European Space Agency, GOCE, Earth Observation, Japan
Publication: News.Discovery.com
Publication Date: 03/11/2013

Strongest air density perturbation was felt by the GOCE satellite approximately 29 minutes after the 2011 Japan eathquake. Image credit: ESA

The European Space Agency’s (ESA) Gravity Ocean Circulation Explorer (GOCE) satellite was able to detect the 2011 earthquake that killed approximately 16,000 people in Japan, caused widespread destruction, and almost triggered a nuclear crisis. The discovery gives seismologists a new tool to get germane data to study and understand the Earth’s movements.

Scientists claim that large quakes make the surface of the planet vibrate, which produces sound waves that travel upwards through the atmosphere. According to a report published in Geophysical Research Letters, the atmospheric infrasounds created by the earthquake in Japan affected the air density and vertical acceleration of the GOCE platform.

The report indicates that the satellite observed perturbations up to 11 percent of air density and a vertical acceleration of air waves after the earthquake. "These perturbations were due to acoustic waves creating vertical velocities up to 130 meters per second," the report noted. GOCE first recorded the signal as it passed over the Pacific Ocean almost 30 minutes after the quake, and then again 25 minutes later as it moved across Europe.

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