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31

The shuttle (and ISS) EMU (Extravehicular Mobility Unit) has a condensing heat exchanger as part of its ventilation loop. The condensate is stored, used for cooling, and the excess is drained after each EVA (Extravehicular Activity). Reference: Shuttle Crew Operations Manual: https://www.nasa.gov/centers/johnson/pdf/...


18

The US's only "modern, real" space suit, the Extravehicular Mobility Unit (EMU), was designed in the 1970s. It has a very limited sensor suite and no automation at all. The only sensors used in the suit are A biomedical harness (with electrocardiograph electrodes) A carbon dioxide (CO2) partial pressure sensor A total pressure sensor ventilation flow ...


12

It's one of several factors to prevent Earth microorganisms from contaminating the moon. The Apollo Program Summary Report states 8.5.2.1 Lunar-surface contamination.- Nations involved in the exploration of extraterrestrial bodies have agreed to take all steps that are technically feasible to prevent the contam- ination of these bodies during ...


11

I'm sure there are different techniques for different space suits, but here's an example of how it is done for the ISS suits: The key to handling body heat and sweat is the Liquid Ventilation Garment, or LVC. This is essentially what looks like a full body thermal underwear, but it is lined with tubes that pass water through them. If you heat up, cold ...


9

There are two different effects of oxygen toxicity, the Lorrain-Smith-effect and the Paul-Bert-effect. See Wikipedia. The Lorrain-Smith-effect may occur at a partial oxygen pressure above 0.5 bar for more than about 24 hours. It is a lung toxicity. The Paul-Bert-effect may occur at a partial pressure above 1.6 bar for minutes to a few hours. It is a ...


8

The potassium deficiency issues on the Apollo missions were at least to some degree due to exertion during the lunar EVAs. Despite the low gravity, the stiffness of pressurized spacesuits made what would otherwise be moderate activity more strenuous; the astronauts sweated off several pounds each according to Biomedical Results of Apollo: All Apollo ...


8

It's a lot worse in space than on land. Quantitative studies on wound healing in zero g haven't really been done as of about 2013 (the latest paper I could find). However, there are some sources that explain some of the issues. The first one, here, talks about how astronauts say that minor wounds don't heal until they are back on Earth (sorry, the exact ...


8

Surface tension! The short answer is you’re close with your first guess - by squeezing the bottle a drop forms at the tip that is stable due to surface tension, and then steering that drop into an open eye (usually with the help of a partner doing the actual instilling). This means the bottle tip itself never touches the eye if you’re doing it right, ...


7

Yes; NASA selected bok choy, aka "Chinese cabbage", for one of their recent garden experiments, quite possibly because of its high vitamin c content (45mg, half of your daily recommended dose, per 100g). The mission launched in 2014, and as far as I'm aware was a success but I haven't tracked down the specific paper recounting the experiment, if anyone's ...


6

We have an answer for Shuttle, and an answer for ISS. Here is the answer for Apollo. The main strategy was to prevent sweating in the first place. The astronauts wore a Liquid Cooling Ventilation Garment (LCVG), which was essentially long underwear with closed tubes that circulated cooling water. Heat was discarded through the sublimator on the suit's ...


5

The Crew Systems Division postflight report for Apollo 11 states that Suiting was completed at 06:17 with an O2 concentration check at 06:21 indicating 100 % 02 in the suit. Launch was at 08:32 and the crew removed their helmets at ~ 08:45.


5

Well, there are probably several body motions that can exacerbate SAS. Anecdotally, I can tell you that it was well understood by Shuttle flight crew that the act of doffing the Advanced Crew Escape Suit (ACES) (which usually occurred within a few hours of orbital insertion) was considered especially provocative with respect to the SAS problem. This was ...


4

The extremely frank discussion of the post-landing period found in long-duration crewmember Clayton Anderson's "The Ordinary Spaceman" makes it clear that, for him at least, the transition was largely vestibular and regaining habit patterns. Upright for the first time on Earth in over five months, the entire middeck of the orbiter began to spin ...


4

How this is managed is a bit complex. The short answer is there may well be some clever ticks but weight constraints mean an effective radiation shield is not really a feasible option and apollo-style steel/aluminum capsules are near guaranteed, with the addressing being left to management things like returning crews near their limit of exposure. As for the ...


3

Sadly, they aren't really, except after the fact by looking at filters. Particulate matter is removed from the air by HEPA filters located in the Common Cabin Air Assemblies (a fan/heat exchanger device). When my information was current, the filters were cleaned approximately every 90 days. Some problems caused by accumulation of particles/dust are listed ...


3

Airborne dust was observed, which caused great concern among the crew and medical personnel. However, actual post-flight respiratory results were normal. The Apollo Program Summary Report describes dust problems and their mitigation: A troublesome and ever-present problem that was corrected only partly during lunar surface missions was that of dust, On ...


3

A partial answer: according to Garret Erin Reisman, professor of astronautical engineering and former SpaceX human spaceflight developer, the current state of knowledge is that you can get around a loss of bone mass almost entirely by proper exercise. The key to this is that bone loss is basically an issue of a lack of stimulation, and not a lack of ...


3

How will Starship ... accommodate micro-gravity? As of today, it won't. Making non-micro gravity by spinning about its long axis is impractical because the ship's radius is only 15 feet. Others have made detailed calculations for spinning about other axes. This is the kind of thing that helps SpaceX cultivate its bonkers-but-works reputation, but SpaceX ...


3

I don't consider this answer to be definitive, but it's most likely the best we will do here... I remember hearing some stories around NASA's Astronaut Office, probably in the ~1998 time frame, about STS-51-D (Jake Garn's flight - which happened in April, 1985). The running joke, at the time, was that the second-highest Garn level ever achieved, to that ...


3

Immune system of Russian cosmonauts after orbital space flights Rykova M.P. Human Physiology. 2013. Т. 39. № 5. С. 557-566. The article is an overview of the results of studies of the immune systems of cosmonauts. The use of a system approach to the evaluation of the various components of the immune system made it possible to identify a number of ...


3

Yes. They have little in common, beyond both resulting in a mismatch between vestibular data input to the brain and what’s actually going on, resulting in symptoms that impair performance. In SAS, our best theory is that the shift from 1G to microgravity environment essentially results in a dropoff from baseline vestibular input that the brain seeks to ...


2

The answer appears to be "yes", even for those astronauts who stayed in LEO, shielded by earth's magnetic field. Examples are weakened tumor defences: https://www.physiology.org/doi/abs/10.1152/japplphysiol.00761.2018 Reacticated virusses from stress exposure: https://www.frontiersin.org/articles/10.3389/fmicb.2019.00016/full#h1 And more when searching "...


2

Your last sentence hits the major point. Other than Apollo, no humans have been outside of the Van Allen radiation belts. All of the astronauts on the nine space stations have been largely spared the radiation that they would be subject to for the months-long trip to Mars and back. The Apollo astronauts did get such an exposure, but their missions lasted ...


2

First off, I'd caution the jump to conclusion in title: There's a reason we re-named VIIP to Spaceflight Associated Neuro-Ocular Syndrome (SANS) - because while we suspect there's elevations of ICP going on, there's still little direct evidence of it and a suspicion that if there is, the ICP elevation alone is likely not sufficient to explain the syndrome ...


2

First we must compare the surface gravities of Earth and Mars. Planet Earth has 2.63 g if we consider Martian gravity 1 g. So a Martian going to Earth is similar to an Earthling visiting Jupiter a bit closer to its poles. Humans live in the Earth's gravity for (almost) their entire lives and I think they couldn't spend days on floating cities on Jupiter ...


1

From here (images too sloppy to copy text from) The link has some statistical results. A more recent (1985) description can be found on pages 23-25 of this paper; again, the text is not readily copy-able. It does say, in reference to the Mercury tests The 15 tests used for astronaut selection primarily examined the neuropsychological and ...


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