Goce, satellite and earthquake detector
Yesterday (March 11) marked the second anniversary of the Tohoku, Japan, earthquake, a whopping 9.0 on the Richter scale. Scientists now say that its low-frequency acoustic waves were felt at the edge of space.
The Goce satellite, orbiting Earth at a mere 255 kilometers, actually drags through the top of the atmosphere. Because of its low orbit and its senstive accelerometers, Goce detected the acoustic waves.
Scientists are now checking the European Space Agency (Esa) craft to see if it recorded an infrasonic signal when an asteroid exploded last month over Chelyabinsk, Russia.
Goce’s primary purpose is to map subtle differences in the pull of gravity across the Earth’s surface, caused by uneven distribution of mass. In June, Esa will lower its orbit to 230 kilometers in an effort to obtain finer detail.
Goce is running low on fuel and is nearing the end of its mission. Esa will likely command the satellite to fall back to Earth in November.
It’s amazing that a human-built satellite in space can feel a quake on Earth. Even more amazing is that the quietest whisper of prayer is heard by the God of the Universe.
I’ve been sharing links to your articles here on Twitter from time to time. I shared a link to this one. Good stuff Bonnie!
Thanks, Denise. I appreciate your Tweeting. And it’s fun to ferret out all these geek-science tidbits.