SpaceX's next private astronaut launch to ISS, Ax-4, delayed to June 8 Roscosmos cosmonaut Pyotr Dubrov performs a spacewalk in June 2021 at the International Space Station. The Russian Zvezda module appears below him in the picture. To the right is the old Russian Pirs docking port, which was removed to make way for the updated Nauka science and docking module in July 2021. (Image credit: NASA) Cosmonauts recently detected a "new pressure signature" in the Zvezda service module, part of the Russian segment of the ISS, NASA officials announced in an update today (June 12). This development isn't exactly a shock; this area first sprang a leak back in 2019, and cosmonauts have been dealing with it ever since, as the recent spot check shows. The cosmonauts "sealed some additional areas of interest and measured the current leak rate," NASA officials wrote in the update. "Following this effort, the segment now is holding pressure." Still, the agency and Axiom Space, the Houston company that organized Ax-4, decided that grounding the mission for now is the prudent course of action. Get the Space.com Newsletter