Antarctica from space (NASA image) |
The news keeps getting stranger from Antarctica. First there was the iceberg (and maybe two) shaped like a perfect rectangle or parallelogram. Then there was a scientist-on-scientist stabbing at a remote Russian station that was blamed on the stabbee spoiling book endings for the stabber. Now comes word that NASA data from a satellite which died five years ago shows multiple lost continents underneath the frozen one. Dead men may tell no tales but it looks like dead satellites can.
“In East Antarctica we see an exciting mosaic of geological features that reveal fundamental similarities and differences between the crust beneath Antarctica and other continents it was joined to until 160 million years ago.”
Commenting in a statement *with map) about a new study in Scientific Reports titled “Earth tectonics as seen by GOCE – Enhanced satellite gravity gradient imaging,” co-author Fausto Ferraccioli reveals what he and a team of researchers from Kiel University and the British Antarctic Survey found after five years of studying data from the European Space Agency’s GOCE (Gravity field and Ocean Circulation Explorer) mission – a gravity-mapping satellite in operation from March 17, 2009, until October 21, 2013, when the very thing it was mapping pulled it to its atmospheric demise. Nicknamed “‘the Ferrari of space” — possibly because of its sleek silver design or its supply of xenon propellant which allowed it to resist drag while it dipped down to a 225 km altitude for highly accurate gravity measurements – the GOCE measured Earth’s gravity more precisely than any satellite ever.
“These gravity images are revolutionising our ability to study the least understood continent on Earth, Antarctica.”
Specifically, those high-resolution images showed gravity gradients – measurements of how rapidly the acceleration of gravity changes – allowed them to search the lithosphere – the solid crust and molten mantle hidden underneath Antarctica’s thick ice – for remnants of ancient ocean beds and cratons, which are highly folded orogen (belt of the earth’s crust involved in the formation of mountains) regions left from previous lost continents that Antarctica was once connected to.
The team released a short video (see it here) showing how these long-lost continents may have looked as they moved around Antarctica – bumping into it, breaking off and floating away.
Is this a big deal?
“Overall, we emphasise that satellite data such as from the GOCE mission, provide novel datasets with a global homogenous coverage that can significantly advance our understanding of the Earth structure and tectonic setting.”
That’s a ‘yes’. Understanding the early history of Earth’s tectonic plates helps predict future earthquakes … and it’s just plain interesting. Perhaps someday, another “Formula One” satellite will tell us once and for all if Antarctica was once occupied by humans … or aliens.
And studying Antarctica from space seems to be safer than a surface look with colleagues who are book spoilers.
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