The Russian space agency Roscosmos is investigating a coolant leak that has occurred on one of its modules on the International Space Station. This incident adds to the growing list of mechanical problems that the agency has encountered in low-Earth orbit throughout the past year. In a notice posted on the messaging site Telegram on Monday, Roscosmos indicated that the coolant leak has impacted a radiator circuit on the Nauka module, situated within the Russian-controlled section of the ISS.
The Nauka module, which was added to the space station in July 2021, experienced a leak on an external backup radiator. This radiator had been delivered to the ISS during a space shuttle mission in 2010, as confirmed by NASA. A translated version of the message stated that the module's main thermal control circuit continues to function normally, ensuring comfortable conditions in the living area. The crew and the station remain unharmed and there is no imminent danger.
NASA announced on Monday afternoon that officials in Houston observed flakes coming from one of the two radiators on the Nauka module at 1 p.m. ET. The flight control team informed the crew on the space station about the potential leak, and NASA astronaut Jasmin Moghbeli confirmed the presence of the flakes from the cupola windows. As a precaution against contamination, the crew was then instructed to close the shutters on the windows of the U.S. segment.
NASA confirmed that the primary radiator is operating as expected, ensuring the safety of the ISS crew. Meanwhile, the ground teams will carefully investigate the cause of the leak.
The Russian space agency has been focusing on restoring the efficiency of its crew transportation missions for almost a year. This effort began following a significant coolant leak incident in late 2022, which occurred while one of their Soyuz spacecrafts was docked at the space station. The affected vehicle was responsible for transporting NASA astronaut Frank Rubio, as well as Russian cosmonauts Sergey Prokopyev and Dmitri Petelin, to the International Space Station (ISS) in September 2022.
During a news conference in July, Joel Montalbano, NASAs International Space Station program manager, stated that an investigation conducted by Russian officials, which was later reviewed by NASA, concluded that a small object probably collided with the spacecraft, resulting in the leak. Additionally, Montalbano mentioned that a separate NASA team also examined the incident independently and, based on the information provided by their Russian colleagues, they were unable to find any other possible cause for the incident, apart from some form of external force, debris, or similar factors.
The issue of debris in orbit is becoming increasingly problematic. In recent years, the number of uncontrolled garbage pieces in Earth's orbit has experienced significant growth, partly due to previous collisions among orbiting objects and anti-satellite weapons tests.
After identifying a coolant leak on the Soyuz spacecraft, Roscosmos concluded that the vehicle was no longer safe and opted to launch a replacement capsule in order to bring the crew back to Earth.
The launch of the replacement spacecraft was further postponed following a coolant leak reported by Roscosmos on February 11. This leak occurred on a Russian Progress vehicle, which is responsible for transporting supplies to the ISS. Roscosmos speculated that the leak in the Russian Progress vehicle was also a result of external influences.
A replacement Soyuz finally launched to the ISS in late February. That vehicle safely returned Rubio, Prokopyev and Petelin to Earth on September 27.
