A leak was discovered in the cooling system of the Soyuz MS-22 spacecraft, as a result, Russian cosmonauts were unable to leave the International Space Station. Roscosmos said that the cause of the damage was a meteorite impact. As Vitaly Yegorov, a popularizer of astronautics and author of the Zelenyikot blog, told The Insider, the probability of being hit by a meteorite is very small, and all previous breakdowns on the ISS were associated with internal malfunctions. He also named options for the safe return of the crew home in this situation.
Roscosmos claims that the damage was due to a meteorite impact or space debris. As a result of breaking through the living compartment, the refrigerant leaked out, which is located in the external cooling circuit of the instrument-aggregate compartment of the Soyuz. The instrument and assembly compartment is a technical and non-residential part, and therefore such damage does not pose a direct threat to the crew. The task is to maintain the desired temperature in this compartment so that the fuel does not overheat and freeze.
The station has anti-meteorite protection, as well as on the Soyuz spacecraft, but it protects only the residential part, and the instrument and assembly compartment is not protected, because there is no life there and it is believed that hitting it is not as dangerous as the living compartment. In the International Space Station, too, almost all residential parts are protected, but mostly from the “windward” side. In photographs, the ISS looks like such an amorphous structure with antennas and solar panels that stick out in different directions, but in fact the ISS has a front and aft. The bow section, which meets the entire flow, is protected. There is a protection system - the so-called Whipple shields - these are several layers of aluminum spaced a short distance, and they can hold a nut or meteorite up to 1 cm in size at a speed of about 8 km / s, that is, the first space speed at which space debris can fly . Our segment is in the stern, so only parts of it are covered with protection, but in general the hull itself with modules is not covered, because it is believed that the probability of being hit is very small.
We have not yet seen photographs of the leak itself, only footage taken from the American Canadarm manipulator has been published. This manipulator cannot see everything, but he managed to see that a stream of liquid is really gushing out of the Soyuz, but from the reverse side - and from which place exactly, it is not clear.
Just out of scientific interest, I would like to look at the site of the defeat by a large piece of space debris (at least a centimeter in diameter, judging by the fountain that whipped there). I would wait for the final photos from Roskosmos so that we can accurately see this place and determine if a natural bullet actually flew there or if this is an internal malfunction.
I would not rule out an internal malfunction simply because this system is under pressure, the option of some kind of marriage or rupture of some line or pump is quite possible. It is easiest to blame the meteorite, but in almost all previous emergency situations in space, it was still man, not nature, who was to blame. You can remember the previous hole on the Soyuz, and there, too, at first they said: “Perhaps a micrometeorite.” And when NASA published images that clearly show the holes from the drill, Roscosmos said: “Well, yes, it was an impact from the inside, apparently.” If NASA had not published, they would still be talking about the meteorite. We do not know exactly what happened, which caused the coolant line to break, and we will wait for the results if Roscosmos makes them public.
It is practically impossible to repair such damage in orbit if it is a penetration with a violation of several layers of skin and pipeline. There are no such technologies to brew, solder and twist with electrical tape. Not in a spacecraft, which is completely unsuitable for such work in space - there are no handrails, nor the necessary elements for opening bulkheads. It all looks like a gamble, and the coolant has already flown away. If we repair the pipeline, there will still be a vacuum inside it, so there is no point in this anymore.
If anything, the next spacecraft, the Soyuz MS-23, is already being prepared at Baikonur, it can be launched in an unmanned mode so that it reaches the station and the crew can return home safely. But I would suggest that they work until the end of the next expedition, so as not to waste the spaceship. It's just that the guys would have an expedition not for six months, but for a year. It is hard, but feasible, such expeditions have already been.
The most extreme option is to ask the Americans for help to send their Crew Dragon to SpaceX, and he, too, could perform such a rescue mission. Elon Musk would not refuse, and maybe NASA would even pay for this expedition, because the expedition includes the American Frank Rubio. NASA is certainly interested in its safe return and maybe could pay for such an emergency Crew Dragon flight, but ours will do everything to avoid this scenario for political reasons.
The riskiest and easiest option is to get on a ship now and fly home. It doesn't take that long to get back from space, about three hours, and the engines don't need to run all that time, and that temperature range that the propellant needs to stay in is easy to maintain in space because the sun is shining. The main thing here is to maintain a balance between cooling and heating. And in general, I think they can afford to take such a risk. It is not known whether the American will agree, but they trust our specialists. This scenario is especially beneficial for Roskosmos, because this instrumental-aggregate compartment will burn up in dense layers of the atmosphere, separating from the descent capsule, and no one will know what actually happened on it. But this is all guesswork and various scenarios.