While problems in electricals, oxygen leak, and unfavourable weather conditions were initially behind the delays of Axiom-4 space mission, it was an issue related to pressurisation in one of the modules of the International Space Station (ISS) that has now led to the mission being delayed indefinitely. “The revised launch schedule will be announced by Nasa and Axiom after the activities and technical reviews are satisfactorily completed,” the Indian Space Research Organisation (Isro) said in a statement.
Indian astronaut Group Captain Shubhanshu Shukla is set to travel to space on board the Axiom-4 mission, making him the country’s second astronaut in space and the first on the ISS. Shukla will spend nearly 14 days at the ISS, conducting science experiments.
On Friday, Isro provided a timeline of what led to the delays. The launch was initially targeted for May 29 but was deferred due to an “observation in the electrical harness” of the SpaceX Dragon spacecraft — the module where the crew is seated for their journey to the ISS. The launch was then pushed to June 8 and then again by another day due to the delay in preparedness of the SpaceX Falcon 9 launch vehicle.
The space agency said the launch was again pushed for a day due to unfavourable weather conditions on the ascent path of the rocket.
In parallel, when the engines were test-fired on ground on June 8, an oxygen leak was observed in addition to an anomaly in one of the actuators. “Anticipating the quick resolution of LOX (liquid oxygen) leak issue, the launch was rescheduled to June 11, 2025,” the space agency said, adding that it had suggested that the repairs and replacements could be carried out without moving or disassembling the vehicle. The Indian space agency suggested a low temperature leak test — a test that could assess the integrity of the components at very low temperatures — to validate the performance before moving for the final launch.
On June 11, however, Nasa informed that it was working with the Russian space agency to evaluate a “new pressure signature” that could indicate a leak in the back section of one of Russian modules of the space station — ISS Zvezda. This comes after a recent repair effort.
The leak in the Zvezda module was first detected in 2019 and the space agencies have been working for years trying to fix it. Now, cosmonauts on board the space station have conducted inspections of the pressurised interior surfaces of the module, sealed off some “additional areas of interest”, and measured the current leak rate. “The segment now is holding pressure,” Nasa said in a statement.
Story continues below this ad
The Axiom-4 mission was postponed, nonetheless, to provide additional time to Nasa and Roscosmos to evaluate the situation and determine if any additional troubleshooting might be needed.
