NASA confirms renewed ISS leak in Russian PrK module

NASA has confirmed that the International Space Station's Russian PrK module—a transfer tunnel on the Zvezda Service Module—has resumed leaking atmosphere into space. After months of inspections and sealant applications that had stabilized the pressure in January, the leak returned three weeks ago. On May 1, following cargo unloading from a Progress spacecraft, Roscosmos detected a slow pressure drop. NASA's Josh Finch stated the leak rate is about one pound per day, and the area is now maintained at a lower pressure with small repressurizations as needed. There are no impacts to crew operations, and both agencies are coordinating next steps.

Internally, NASA has classified the risk as a 5 on both likelihood and consequence in its 5×5 risk matrix, with potential for catastrophic failure discussed in meetings. Roscosmos has managed the problem by keeping the hatch closed, but the reemergence of cracks—some modules are nearly three decades old—calls into question long-term viability. The U.S. is considering extending ISS operations beyond 2030, but this leak underscores the need for commercial station replacements. Former NASA director Phil McAlister argues the incident confirms the wisdom of retiring the ISS by 2030 in favor of safer, modern commercial platforms.