Operators recently pinpointed an air leak on the International Space Station (ISS) to a Russian module, using an ingenious method involving tea leaves before sealing it effectively.
The ISS, approaching its 20th anniversary in orbit, routinely loses small amounts of air, requiring periodic resupply of oxygen and nitrogen via cargo vehicles. About a year ago, mission control detected a slight uptick in the leak rate, indicating a minor breach aboard the station.
Initially deemed non-critical, the issue was monitored for months. Action ramped up in early September when the leak rate increased fivefold. Astronaut Chris Cassidy and cosmonauts Anatoly Ivanishin and Ivan Vagner systematically isolated modules by closing hatches and using ultrasonic leak detectors. They soon traced the problem to the Zvezda service module, the core of the Russian segment.
On Thursday, Roscosmos confirmed the crew had precisely located the leak through an unconventional test. Cosmonaut Anatoly Ivanishin scattered tea leaves from a tea bag inside Zvezda's transfer chamber. With hatches sealed, the crew observed via video as the leaves floated in microgravity.
The leaves drifted toward the module's communication equipment, signaling a small crack in the hull. The cosmonauts sealed it with Kapton adhesive tape, a material proven reliable across extreme temperatures, per Roscosmos. A more permanent patch is planned soon.
Zvezda and other Russian modules are among the ISS's oldest components. Recent issues include toilet malfunctions and an oxygen generator failure, which the crew repaired this Saturday, according to Roscosmos.
This isn't the first leak in the Russian segment. In August 2018, a 2-millimeter hole was found in a docked Soyuz capsule, initially concealed by paint that later flaked off. Cosmonauts repaired it using epoxy sealant.
