The International Space Station (ISS), a flagship of human collaboration in space, is showing signs of aging after 25 years in orbit. Among the challenges it faces, one of the most concerning concerns cracks and leaks detected in the PrK module, a compartment essential to its operations. How do space agencies and crew manage these issues to extend the life of this unique scientific platform?
The PrK module: a weakened nerve point
The module PrKwhich is part of the Russian segment of the ISS, plays a crucial role. Built to accommodate cargos Progress which supply the station, it serves as a passage to transport equipment and waste. However, cracks have appeared on this module, which causes air leaks. NASA and Roscosmos, the Russian space agency, have classified these leaks at the maximum risk level in their assessment matrices: both highly probable and having serious consequences.
The potential causes of these cracks are numerous. Roscosmos attributes them mainly to the cyclic fatigue caused by microvibrationsan inevitable phenomenon in orbit. For its part, NASA believes that the cracks are the result of a complex mix of factors (internal pressure, mechanical stresses, material properties and exposure to the rigors of the space environment). Despite several repairs, the leaks could not be completely eliminated. While contained for now, they raise questions about the durability of the structure and how operations can continue safely.
Divergent views on risks
PrK leaks also reveal differences in risk management between agencies. For Roscosmos, the situation is under control and catastrophic disintegration of the module is considered unlikely. NASA shows itself on the other hand more careful and raises concerns about the long-term structural integrity of PrK. This disagreement has practical implications: at what point will the leakage rate become unsustainable? When will it be necessary to permanently seal the PrK hatch, which will condemn one of the four Russian docking ports on the ISS?
Despite these differences, collaboration remains essential. Roscosmos shares metal samples and analysis reports with NASA, while independent experts are called in to determine the causes of the cracks and propose solutions.
Measures to guarantee crew safety
Faced with uncertainty, strict precautions have been put in place to limit risks. The crew keeps the PrK hatch closed when not in use. During unloading or repairs, cosmonauts inspect the module and try to seal any cracks. As a precaution, American astronauts also close the hatch that separates the Russian segment from the American segment during these operations.
These precautions affect the crew's daily life, but they are necessary. As NASA astronaut Michael Barratt explains: “It is not a comfortable situation, but it is the best compromise to ensure the safety of everyone on board. »
An aging station, but essential
The ISS was launched in 1998, and some of its modules, such as the PrK and Zvezda, have been in service since July 2000. With age, material wear becomes inevitable and the PrK illustrates this challenge well. Despite this, the'ISS remains irreplaceable. It is in fact today the only platform allowing large-scale research in microgravity, thus contributing to advances in fields as varied as medicine, materials physics and space technologies. In addition, it plays a key role in the preparation of future manned missions to the Moon and Mars. Its scientific, strategic and diplomatic importance is therefore immense.
This is why NASA wants to extend its operation at least until 2030, supported by several international partners. Roscosmos, the Russian space agency, has however expressed reservations and plans to withdraw from operations as early as 2028, which leaves uncertainty over the future of the station. This discrepancy reflects different priorities and constraints between the partners, but it also highlights a reality: keeping an aging station in operation requires considerable technical and financial efforts.
Faced with these challenges, the question is not only how long the ISS can remain operational, but also how it can continue to play a central role in space exploration and scientific research despite the growing challenges of its age.
