Russia's main space corporation, Roscosmos, provided updates on Tuesday about its two spacecraft that recently suffered failures to their cooling systems while attached to the International Space Station.
Although there were several items of note in these updates—which are not readily available to Western audiences due to Russian Internet restrictions—perhaps the most surprising claim is that both the Soyuz MS-22 and Progress MS-21 spacecraft were damaged near their heat radiators by "external impacts." This seems highly improbable, to say the least.
For those who haven't been paying attention to the Russian roulette in space in recent months, here's a summary of what has happened since mid-December:
- On December 14, 2022, as two cosmonauts were preparing to conduct a spacewalk outside the space station, the Soyuz MS-22 spacecraft docked nearby began to leak uncontrollably from its external cooling loop. This Soyuz MS-22 spacecraft had been due to bring cosmonauts Sergey Prokopyev and Dmitri Petelin, as well as NASA's Frank Rubio, back to Earth in March.
- On January 11, 2023, Roscosmos confirmed that a micrometeorite had struck the external cooling loop of the spacecraft and deemed it unsafe to fly home. Officials from Roscosmos and NASA said a replacement Soyuz spacecraft would launch to and autonomously dock with the station in February. The crew that would have flown in the damaged Soyuz MS-22 vehicle, including Rubio, will instead fly home in this Soyuz MS-23 spacecraft later in 2023.
- On February 11, 2023, the Progress MS-21 supply ship attached to the International Space Station lost pressure in its external cooling system. Once again, all of the coolant on board a Russian spacecraft leaked into space due to a rupture. This vehicle, which had been docked to the ISS since October, has detached. Before it reentered Earth's atmosphere, the vehicle rotated itself to allow cosmonauts to photograph the damaged area.
Tuesday's updates provide some new information. In one of them, Roscosmos confirmed that the uncrewed Soyuz MS-23 spacecraft would launch to the space station on Friday at 00:24 UTC from Baikonur Cosmodrome in Kazakhstan. It will dock autonomously with the space station about two days later. Prokopyev, Petelin, and Rubio will fly home aboard this Soyuz in September. The Russian space corporation also said it does not plan any upgrades to the thermal control systems on its Soyuz and Progress vehicles, as this would be costly and increase the mass of the spacecraft.
In a second update, Roscosmos draws preliminary conclusions about the failure of the Progress MS-21 ship. "Based on a preliminary assessment of the situation with Progress MS-21 ... the cargo ship experienced an external impact. This conclusion was made based on photos that revealed changes on the exterior of the vehicle." An external impact likely means either a micrometeorite or small fragment of orbital debris must have struck the Progress spacecraft.
As part of the update, Roscosmos released a photograph of the impact site on the Progress vehicle. When this image is compared to a photograph of the Soyuz MS-22 vehicle, there appears to be little commonality in the damaged area:
Although micrometeoroids and specks of orbital debris have periodically damaged the space station and visiting vehicles during more than two decades of operation, impacts have never resulted in "serious consequences" like with the Soyuz and Progress vehicles in the last two months. So what are the odds that two Russian vehicles would be struck in the same general area in two months, with both of these strikes disabling the spacecraft's thermal cooling systems? The odds seem incredibly low.
Moreover, if there are so many micrometeorites intersecting with the space station's orbit, why is the outpost not riddled with holes? NASA does not presently have a sensor or other means of recording hits to the ISS unless they cause notable damage. But given that the Soyuz and Progress vehicles only make up 1 percent or less of the station's footprint in space, the ISS would likely be incurring significant damage if there was a cloud of micrometeorites or debris.
Needless to say, all of this is pretty mysterious.