# Tag Info

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/...

25

This is actually a good question, and one that we really don't have a good answer to. Intuitively it must be better than zero gravity, but the question is, will it be good enough. There are a host of problems associated with long term living in zero gravity, including loss of bone strength and others, it is not currently known if Mars is good enough. The ...

18

If you imagine that in your example the rocket's engine is not initially firing. The rocket and its occupants are falling freely towards the planet below. The occupants will feel weightless, because there is no normal force from any direction. Now, if you point your rocket's nose down and start the engines, the occupants will fall towards the bottom (or ...

16

Nice observation, he is just doing it to show off! Check these out: https://twitter.com/cmdr_hadfield/status/326727757109268481?lang=en

14

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 ...

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

Let's quickly take a glance at the boundaries of the parameter space. As we know, the lower extreme, zero gravity, is pretty unhealthy for humans in the long term. Some effects have been known for some time, like bone and muscle deterioration, and effects linked to changed body fluid dynamics. Other effects were detected more recently, like the epigenetic ...

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

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 ...

9

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 ...

6

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

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

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 ...

5

As a scuba diver I know when to do a Valsalva maneuver to equalize pressure on my ears: only when descending from surface during a fast pressure increase. While ascending from the deepth my ears never needed help in equalizing pressure. For the anatomy of the ears see Wikipedia. The astronauts experienced a fast pressure increase only during the very last ...

5

You can actually experience it yourself. Take for instance an ice-skating athlete, when they perform one of those spinning numbers: the g force in one hand is minus the g force in the opposite hand. And it gradually varies through all their body. What will happen to the human body? With a g force strong enough, it'll get stretched and torn apart.

4

Short answer: No, for several reasons. Longer answer: the apparent gravity from centripetal acceleration was low, and the astronauts likely didn't have enough exposure to get any real benefit. I'm going to have to dig up long unused physics knowledge here. The formula for centripetal acceleration is ac = v2 / r, in other words centripetal acceleration is ...

4

The chapter The Lunar Quarantine Program of Biomedical Results of Apollo (99 Mb pdf, 576 pages) describes the measures taken in the lunar quarantine program. The list of disinfectants that are effective against the virus which causes COVID-19 is provided by the U.S. EPA. Gray tape (duct tape) was used to sweep up and contain dust on the lunar module floor. ...

4

As long as you are in freefall, you don't feel the acceleration of gravity. The reason is that you can't feel force directly, you can only feel force when it doesn't act uniformly on all parts of your body. Example 1: Standing on the ground. Gravity acts uniformly on all parts of your body, but the normal force from the ground acts only on your feet. You ...

4

There are six types of water on the ISS (nothing on the ISS is simple!) Note that the potable water has minerals added "for taste". The shuttle water system added iodine to its potable water by running fuel cell product water through a microbial filter. Minerals were not added to the shuttle potable water. The US iodinated water and the Russian silver-...

4

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 ...

4

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

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 ...

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

I'm not quite sure what the documentary you saw was referring to in particular, but it seems likely that Galina Balashova's design work in the Soviet space program is relevant. From the article: Notably, she integrated a lack of gravity into her design, choosing dark colors for the floor and bright colors for the ceiling. There was an important ...

3

The same way all space electronics are radiation hardened. Shielding it directly is not the only way to protect electronics. Instead, radiation-resistant hardware (such as silicon-on-insulator transistors) and logical systems (EDAC/Error Detection And Correction or ECC/Error Correcting Code). Triple Modular Redundancy is really common as well, where three ...

3

Yes. It's still early when Tsibliyev slips out of the quarantine rooms in the Prophylactorum ... Dragonfly, Bryan Burrough, page 68 This was in preparation for the Soyuz-25 mission to Mir. Crewmembers flying to Mir on the Shuttle went through a normal Shuttle quarantine. "We'd like to thank all the people down on Earth," he continued. "There was ...

3

First of all we are confident enough that special relativity is correct that we know we would not need to worry about the speed as such: everyone is travelling all the time at any speed you like less than $c$ relative to something, and we don't all explode or die or anything. We also know how to deal with the related issues around communication. This is ...

2

The Skylab crew exercised using a bicycle ergometer, not by running around the ring of storage lockers. Image credit - NASA Per the answer to this question Did NASA tell the Skylab astronauts to "Stop running around!"? the crew was directed to not run around the ring of storage lockers any more. They experienced the usual loss of bone minerals. ...

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