Looking at Earth from space , we have learned a lot more about our extraordinary satellite . But sometimes we are forget absolutely clueless on the origin of the features we see .
Thelatest such featureis the peculiar scour marks spot by the Operational Land Imager on the Landsat 8 satellite , which is part of NASA ’s Earth Observatory . The trope is a innate - color view of the shallow waters surrounding the Tyuleniy Archipelago in the Caspian Sea . It shows clearly the islands , the dark green flora on the ocean floor , and some inscrutable " scars " .
An image of the Archipelago from January 17 , 2016 , shows the markings present underneath the sparkler . NASA
These mark were first observed in January , and research worker thought they might have been an passing feature , but they before long came to realize they were actual gull on the sea floor . “ you could tell this by the fact that mark laid down in January have not moved by April , ” Norman Kuring said in astatement . “ If those were pee features , they would not persist through one tidal cycle . ”
NASA decided to put the question toTwitter , break the public the chance to figure out the puzzle . Several explanations were put forward , with human activity being a likely defendant . Both propellers and fisheries employing bottom trawling can rip the vegetation from the ocean flooring .
But the solution is in reality a natural phenomenon : the scour marks were created by ice .
The latest image of the Tyuleniy Archipelago with the marking intelligibly visible . NASA
“ Undoubtedly , most of these tracks are the result of ice gouging , ” order Stanislav Ogorodov , a scientist at Lomonosov Moscow State University , who has previously published research on the phenomenon .
This area of the Caspian Sea is very shallow , no more than 3 meters ( 10 foot ) bass . When it freeze over the ice does n’t reach the bottom , but when the sea starts unfreeze ice fragments are tug against each other , shape " hummocks " – which is a bit like a mound come out of the sea . Some pieces rise above the Earth’s surface , and others are pushed down to the bottom . hint and water system currents move these hummocks around , and their seat haul across the sea floor , make the fall guy see by NASA .
