NASA confirmed Thursday that the Russian segment of the International Space Station has begun leaking atmosphere into space again. It's an old problem that NASA recently hoped was resolved.
For more than half a decade, engineers from Roscosmos and NASA have been tracking the leak rate from a small Russian module attached to the space station that leads to a docking port. The source of these leaks, microscopic structural cracks, have been difficult to find and address.
In January, NASA said that after multiple inspections and sealant applications, the pressure inside this segment, known as the PrK module, had reached a "stable configuration." The PrK module is essentially a transfer tunnel attached to the Zvezda Service Module on the Russian segment of the space station.
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