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In the beginning of the very cool Veritassium video The Bizarre Behavior of Rotating Bodies, Explained, the host Derek Muller says:

In 1985, cosmonaut Vladimir Dzhanibekov was tasked with saving the Soviet space station Salyut-7, which had completely shut down. The mission was so dramatic that the Russian’s made a movie out of it in 2017.

Presumably the movie is called Salyut 7, and it's a clip from the movie rather than historical Salyut-7 spacecraft footage that's showing in the background at around 00:46.

Question: Does the depiction of centimeter-sized water drops floating in front of Dzhanibekov portray an actual event? If so, is that water, and if so, why hasn't it collected on some surfaces somewhere thereby minimizing surface energy?

enter image description here

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  • $\begingroup$ Related: space.stackexchange.com/questions/36287/… and space.stackexchange.com/questions/17439/… $\endgroup$ – Organic Marble Sep 24 at 17:33
  • $\begingroup$ I don't see how collecting on a surface would minimize surface energy $\endgroup$ – Hagen von Eitzen Sep 24 at 17:41
  • $\begingroup$ @HagenvonEitzen you don't see water droplets sticking to hydrophilic surfaces as energy minimization? $\endgroup$ – uhoh Sep 24 at 18:02
  • $\begingroup$ @uhoh The actual minimum would be achieved by the water forming big drops in half-sphere shape (or other calottes - the exact boundary angle depends on the material; for my metal kitchen sink, it seems to be 45° ... 90°) on appropriate surfaces. Many such drops would tend to flow together on said surface to form even larger calottes (with same boundary angle), and by disturbations could (partially) leave the surface and float as water balls, which are slightly worse energy-wise. However, I'd expect the abundance of air volume compared to metal or other surface to shift the equilibrum. $\endgroup$ – Hagen von Eitzen Sep 24 at 20:21
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    $\begingroup$ That move was filled with completely made up events, like major plot points that never happened. So I would not assume anything in it was depicted realistically. $\endgroup$ – Johnny Robinson Sep 25 at 2:40
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This is an artistic exaggeration. Hyperbole.

Salvation of the Salyut-7 station: the cosmonaut Savinykh revealed the details of the feat

The peak moment came when everything began to melt at positive temperature. The regeneration system did not work for two weeks. Plus, a person releases about 800 grams of water through the pores per day. As a result, the entire station was covered with a thin film of water. Sometimes you hit a wall, and from there a swarm of small spray flies out. They cleaned the water with rags. Everything that was at hand went into play. Even things from the previous expedition were torn to pieces. All connectors that docked were thoroughly wiped. A drop of water could get in and a short circuit would occur. A fire could break out at any moment. We were very afraid of this situation. There was a time when Volodya and I slept in turns. Then they turned on ventilation, a refrigeration-drying unit that takes moisture from a large volume.

Пиковый момент наступил, когда при плюсовой температуре все начало таять. Система регенерации не работала две недели. Плюс человек в сутки через поры выделяет примерно 800 граммов воды. В результате вся станция покрылась тонкой пленкой воды. Бывало, стукнешь по стенке, а оттуда вылетает рой мелких брызг. Убирали воду тряпками. В ход пошло все, что было под рукой. Разорвали на лоскуты даже вещи от предыдущей экспедиции. Все разъемы, которые стыковали, тщательно протирали. Могла попасть капелька воды, и произошло бы короткое замыкание. В любой момент мог вспыхнуть пожар. Мы очень боялись такой ситуации. Было время, когда мы с Володей спали по очереди. Потом уже включили вентиляцию, холодильно-сушильный агрегат, который забирает влагу из большого объема. На седьмой день полета восстановить контроль над станцией.

a book is written about these events - the Savinykh memoirs "Letters from the Dead Station" («Записки с мертвой станции»)

Quote from the memoirs:

August 2. The morning of this day began early. The rise at 4.00, and at 4.30 - already medical control. We slept for three hours. The mood is fighting. Two days they were looking forward to this event, since they already wanted not just to make a way out, but rather to quickly complete the necessary work to build up additional solar panels. The station became cold, temperature 13 degrees, a lot of moisture. The moisture appeared already not only on the windows and structures of the station, but also near the berths. In general, how we joked these days, answering the Earth’s question, that we fly in the middle of the station and don’t walk on water, because we don’t touch the walls.

2 августа. Утро этого дня началось рано. Подъем в 4.00, а в 4.30 — уже медконтроль. Спали три часа. Настроение боевое. Два дня с нетерпением ждали этого события, так как уже хотели не просто выход сделать, а поскорее выполнить необходимую работу по наращиванию дополнительных солнечных батарей. В станции стало холодно, температура 13 градусов, очень много влаги. Она появилась уже не только на иллюминаторах и конструкциях станции, но и около спальных мест. В общем, как мы шутили эти дни, отвечая на вопрос Земли, что летаем в середине станции и по воде не ходим, так как не касаемся стен.

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    $\begingroup$ Thank you again for another authoritative and well-sourced answer! $\endgroup$ – uhoh Sep 25 at 6:10
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    $\begingroup$ Your translations are fantastic! Thanks again. $\endgroup$ – Magic Octopus Urn Sep 25 at 17:54

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