martes, 12 de marzo de 2013

Japan quake 'heard at edge of space'

Image credit: CC 2.0 Jeremy Lock

Scientists have stated that the Tohoku earthquake in 2011 was so big that it was picked up from space. The magnitude 9.0 quake caused such a disturbance that it sent a ripple of sound through the atmosphere and was picked up by the orbiting Goce satellite more than 255km above the Earth's surface. It is the first time a spacecraft has been able to pick up the low-frequency acoustic waves from a tremor occurring on the ground.
"We've looked for this signal before with other satellites and haven't seen it, and I think that's because you need an incredibly fine instrument," said ESA's Dr Rune Floberghagen. "Goce's accelerometers are about a hundred times more sensitive than any previous instrumentation and we detected the acoustic wave not once, but twice - passing through it over the Pacific and over Europe." The great Tohoku earthquake in Japan two years ago was so big its effects were even felt at the edge of space.

source and credit unexplained-mysteries