NASA, International Space Station
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From the ISS, NASA astronaut Don Pettit captured rare purple lightning and mysterious upper-atmosphere flashes above massive storms, revealing a hidden electrical world few ever witness from Earth.
For the better part of half a decade, Russian cosmonauts have been searching for the small leaks like a proverbial needle in a haystack. They would periodically close the hatch leading to the PrK module and then, upon re-opening it, look for tiny accumulations of dust to indicate the leak sites.