Russia's uncrewed Soyuz rescue spacecraft docks with ISS

Feb. 25 (UPI) -- A Russian spacecraft docked with the International Space Station on Saturday to replace one that leaked coolant after it was struck by a meteoroid last year, stranding two cosmonauts and a NASA astronaut in space.

"Contact and capture. Docking confirmed at 6:58 p.m. CST," NASA spokesman Robert Navias said during a broadcast of the mission. "It could not have gone smoother from launch to docking."

A Russian translator could be heard congratulating the mission control team for the successful docking, which occurred about three minutes ahead of schedule.

The Soyuz MS-23 spacecraft was launched with 948 pounds of supplies for the astronauts from the Baikonur Cosmodrome in Kazakhstan at 7:24 p.m. EST on Thursday and docked with the ISS after two days in space.

"Assuming a nominal docking this evening, the cosmonauts will conduct leak checks at both sides of the docking interface between Soyuz and the Poisk module before opening the hatches later tonight," Navias said ahead of the docking.

"The cosmonauts will then go to work unloading the 946 (sic) pounds of supplies."

Russia flight directors gave approval for the final approach to the space station around 7:47 p.m. EST, Navias said. The final approach was commanded about two minutes ahead of schedule.

"So far, so good. A smooth and steady approach by Soyuz, 65 meters away," Navias said during the NASA broadcast of the mission.

Russia launched the unmanned Soyuz spacecraft to the space outpost to replace the damaged Soyuz MS-22 spacecraft, which carried the astronauts to the space station in September.

The Soyuz MS-22 spacecraft will remain docked at the ISS until late March when it is expected to return to Earth unmanned, arriving in Kazakhstan after a parachute-assisted landing.

Engineers with Russia's space agency Roscosmos are expected to conduct a post-flight analysis.

The dilemma on how to bring the astronauts home began when the Soyuz MS-22 spacecraft was struck by meteoroid on Dec. 15 and started to leak radiator coolant.

Russia originally had planned to send the replacement spacecraft on Feb. 14 but the rescue mission was put on hold after another Russian spacecraft, the Progress MS-21 cargo ship, also docked at the space station, suffered a similar leak.

Roscosmos and NASA officials previously said that the Soyuz MS-22 spacecraft would only be used for return to earth if an emergency evacuation of the space station was needed, with the two cosmonauts. Rubio would have returned on SpaceX's Crew Dragon Endurance in the case of an emergency.

The dock for the Soyuz MS-23 spacecraft only opened up after the Progress spacecraft was able to undock from the ISS, Navias said Thursday. The progress was deorbited last Saturday and burned up over the Pacific Ocean.

The back-to-back leaks raised questions about whether the rescue craft also might start to leak during flight, possibly because of a design defect. However, the Soyuz MS-23 docked without incident.

Sophie Goguichvili, the program associate for the science and technology innovation program with the Wilson Center think tank in Washington, D.C., told UPI last week that meteoroids will continue to be an issue for Roscosmos and other spaceflight operators.

She also noted that the leak was not the first suffered by a Russian spacecraft. In 2018, a "slight drop" in cabin pressure at the ISS was traced back to a small hole in the habitation compartment of the Soyuz MS-09 spacecraft.

"Upon investigating it, Russia blamed NASA astronauts and even alleged that a U.S. crew member 'drilled the hole' deliberately. So even without the war in Ukraine, diplomatic tensions were high," Goguichvili said.

Because of that incident, Goguichvili called it "understandable" that NASA and Roscosmos would want to investigate further after a second consecutive coolant leak in a matter of months to ensure that Soyuz MS-23 will be capable of returning the three astronauts back home.