Information for the launch of the Soyuz MS-23 unmanned spacecraft to the ISS from the Baikonur cosmodrome
On February 24, 2023 at 03:24 Moscow time from the launch complex of the 31st site of the Baikonur Cosmodrome, it is planned to launch the Soyuz-2.1a launch vehicle with the Soyuz MS-23 unmanned spacecraft. Its automatic docking to the Russian Poisk small research module of the International Space Station is scheduled for February 26 at 04:01 Moscow time/01:01 UTC.
Why will Soyuz MS-23 fly unmanned?
This is done in order to replace the Soyuz MS-22 manned spacecraft on the ISS, on which, for technical reasons, its crew consisting of Roskosmos cosmonauts Sergei Prokop’ev, Dmitrii Petelin and NASA cosmonaut Francisco Rubio cannot return to Earth.
Initially, Roskosmos cosmonauts Oleg Kononenko, Nikolai Chub and NASA cosmonaut Loral O’Hara were supposed to fly to the Soyuz MS-23 station on March 16, 2023.
What happened to Soyuz MS-22?
On December 15, 2022, when the ship was on the ISS in a mothballed state, due to a breakdown of the radiator, the external circuit of the ship’s thermal control system was depressurized with a coolant leak into space. As a result, it became impossible to remove heat from the equipment heated during operation in the instrument and assembly compartment of the Soyuz MS-22, to maintain a comfortable temperature and humidity for the crew in the habitable volume of the ship – the amenity compartment and the descent vehicle.
What caused the breakdown of the Soyuz MS-22 radiator?
Russian specialists have found out that a sporadic micrometeoroid got into the radiator of the ship’s instrumentation compartment. They made such a conclusion after conducting a ground experiment.
NASA helped Roskosmos in investigating the cause of the emergency: when the cameras of the station manipulator SSRMS were examined, a damage site on the Soyuz MS-22 was discovered and filmed – a hole in the radiator about 0.8 mm in size.
After analyzing the available information, experts ruled out the version of the Geminid meteor shower particles getting into the radiator. The option of collision in the manufacture of the radiator and its pipelines at the plant was also carefully considered and did not find confirmation.
According to the results of a ground-based experiment, the possibility of a breakdown of the radiator by space debris was recognized as unlikely, taking into account the direction of movement and the too-high speed of the particle in relation to the flight speed of the station, as well as the absence of possible candidates in the space debris catalogs.
How often do such breakdowns occur in space?
Space flights are always associated with a huge risk of emergency situations that threaten the lives of cosmonauts.
Cases of breakdown by a micrometeoroid of a spacecraft or an orbital station have occurred before, but unlike the Soyuz MS-22, they have never led to such serious consequences. At the same time, so far no country in the world has an observation system that allows tracking micrometeoroids of such dimensions – about 1 mm.
Nevertheless, the ships of the Soyuz family, which have been operating in space since 1966, even in this situation have proven their reliability and survivability.
Is it necessary to improve the thermal control system on the next Soyuz spacecraft?
Modernization of the external contour of the thermal control system of the Soyuz spacecraft with the addition of duplicating functions to it will require large financial resources and time, and will lead to an increase in the mass of the spacecraft. However, this case will certainly be taken into account when developing a new generation of manned spacecraft.
What is the current technical condition of Soyuz MS-22?
After the emergency situation, Russian specialists successfully tested the ship’s motion control system. It was confirmed that, except for the depressurized outer circuit of the thermal control system, all other Soyuz MS-22 systems were not affected and were functioning normally.
While in the station, the Soyuz MS-22 systems are turned off, and its crew – Sergei Prokop’ev, Dmitrii Petelin and Francisco Rubio – live and work in the ISS modules, visiting their ship only when necessary. In order to maintain a comfortable temperature and humidity for the crew, cooled air is supplied to the habitable volume of the Soyuz MS-22 from the Russian Segment of the ISS.
Can the crew land on Soyuz MS-22?
Russian specialists analyzed the state of the ship and technical documentation, and also performed mathematical modeling of thermal processes during the descent of the Soyuz MS-22 from orbit. Taking into account their conclusions and guided by the flight rules, the state commission forbade the use of the Soyuz MS-22 to descend to Earth by its crew – Sergei Prokop’ev, Dmitrii Petelin and Francisco Rubio.
In this regard, it was decided to replace the Soyuz MS-22 by sending the next in the series, Soyuz MS-23 spacecraft, to the ISS in unmanned mode with cargo delivery, and after its successful arrival at the station, land the Soyuz MS-22 without a crew but with cargo onboard.
Specialists discussed the option of launching the Soyuz MS-23 in a manned mode with one cosmonaut, but it would require the completion of the ship, the release of documentation and additional training for the cosmonaut, and the launch would not have been possible before the beginning of March 2023. In addition, this would lead to a change in the composition of subsequent ISS crews.
The option of sending the ship in unmanned mode is more preferable, since it does not have the disadvantages listed above. Among its advantages are the positive statistics of unmanned Soyuz dockings (for example, the Soyuz MS-14 in August 2019) and the ability to prepare the ship for launch as early as February 2023.
Russian specialists in the shortest possible time found out the cause of the breakdown, proposed and carefully worked out the necessary solutions, coordinating them with the partners in the ISS project.
How is the safety of landing of the Soyuz MS-22 crew ensured in case of an accident before the arrival of the Soyuz MS-23?
The probability of an accident requiring emergency evacuation of the crew to Earth is very small.
Nevertheless, by agreement between Roskosmos and the space agencies of the partner countries in the ISS program, the following measures were taken to secure the Soyuz MS-22 crew – Sergei Prokop’ev, Dmitrii Petelin and Francisco Rubio.
Francisco Rubio’s lodgement was temporarily transferred from the Soyuz MS-22 and installed in the American Crew Dragon spacecraft, and instead a cargo stowage was placed in the Soyuz MS-22 seat to maintain the centering of the descent vehicle.
According to the calculations of Russian specialists, the descent of two cosmonauts – Sergei Prokop’ev and Dmitrii Petelin – on the Soyuz MS-22 will be safer in terms of temperature and humidity in the ship than the descent of three people on it.
After the arrival of the Soyuz MS-23, the lodgements of Sergei Prokop’ev, Dmitrii Petelin and Francisco Rubio will be transferred to this ship.
When is the Soyuz MS-22 landing planned?
According to the decision of the state commission, the landing of the ship in unmanned mode is planned in March 2023 southeast of the Kazakh city of Zhezkazgan. This is a regular landing area for Soyuz spacecraft with crews.
The landing of the Soyuz in automatic mode has been fully worked out. For example, in September 2019, Soyuz MS-14 successfully returned to Earth.
Why did the Progress MS-22 cargo ship fly in front of the unmanned Soyuz MS-23?
At the end of 2022, as part of the modernization of the launch complex of the 31st site of the Baikonur Cosmodrome, new ground control system equipment was installed and tested, which replaced the old, obsolete one.
Before being used for launches of Soyuz spacecraft, it had to be checked at the launch of a cargo spacecraft. This was successfully accomplished on February 9, 2023 with the launch of Progress MS-22.
Is there a Soyuz spacecraft at the Baikonur Cosmodrome ready to urgently fly to the ISS in a few days?
There is no such Soyuz rescue ship and never has been in the history of Russian manned cosmonautics. There is no need to have the ship in constant readiness so that, if necessary, urgently send it to the ISS within a few days.
First, the probability of an accident at a plant requiring such steps is extremely low. Secondly, it is financially costly and technically difficult. In particular, it is necessary to store a refueled spacecraft for a long time and keep it constantly ready for the installation of individual cosmonaut sets and cargoes of various weights.
It is also necessary to have a launch vehicle in a high degree of readiness for urgent assembly and docking with the ship and a launch complex at the cosmodrome for emergency rocket reception, refueling and launch. At the same time, it is still necessary to ensure the implementation of the planned launch schedule, and not only for manned launches, each of which has its own schedules for the preparation of its components.
That is why, in such a case, it would be more correct to speed up the preparation of the next Soyuz spacecraft in the series. If necessary, it can be launched to the ISS as early as 45 days after the accident at the station and the adoption of appropriate decisions.
An example is obvious – the accelerated preparation of the Soyuz MS-23 at Baikonur. The ship arrived at the cosmodrome in September 2022, and by the time of the emergency situation with the Soyuz MS-22, it had already passed part of the pre-flight checks, preparing for launch on March 16, 2023. Training was extended over time and included many spare days. Due to this, the schedule was reduced by almost a month and ensured the launch on February 24, 2023.
When is the Soyuz MS-22 crew expected to return to Earth?
Initially, Sergei Prokop’ev, Dmitrii Petelin and Francisco Rubio were supposed to land on the Soyuz MS-22 on March 28, 2023. Now this is planned to be done on Soyuz MS-23 in September 2023.
In modern manned cosmonautics, there were space flights lasting about a year. For example, in 2021, the flight of Roskosmos cosmonaut Pyotr Dubrov and NASA cosmonaut Mark Vande Hei was extended from six months to a year, when they were already in space. The extension itself is positively perceived by the cosmonauts and does not pose a danger to their health.
How will the ISS flight program change due to the situation with Soyuz MS-22?
No tasks of the ISS Russian Segment flight program are canceled, but only shifted “to the right.” Roskosmos cosmonauts Oleg Kononenko, Nikolai Chub and NASA cosmonaut Loral O’Hara will travel to the station in September 2023 on Soyuz MS-24. For about half a year – from the fall of 2023 to the spring of 2024 – the flight on the Soyuz of the first cosmonaut of the Republic of Belarus will be moved.
Linked from ISS Soyuz missions