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180

Clothes require laundry because they have accumulated dirt and other materials from the environment and their wearer. If the astronaut was not wearing those clothes then that material they captured would be released to the environment. In the space station it is a closed environment where such dirt and material would contribute to the accumulated hazards. ...


80

Clothing performs essential duties on the station in addition to modesty. They are an easy way to organize stuff. In addition to pockets, clothing is festooned with velcro strips for attaching tools, pens etc. NASA is working on methods for washing clothes in space. Not surprisingly, they've studied the tradeoffs between including a washing machine in the ...


52

Those are jets of water released by the sound suppression systems installed on the pads and the mobile launcher platforms to protect orbiters and their payloads from being damaged by acoustical energy, reflected from the platform during the liftoff stage of a rocket launch. For example, this is the sound suppression system at the NASA Kennedy Space Center's ...


35

Short answer, No different from Earth in floating. Buoyancy in water or any fluid is based on the weight of water displaced. Floating is based on the weight of the item displacing water. This is ultimately ends up in comparing densities. If the density of the displacing object is greater than the density of the fluid it will weigh more and sink, if it's ...


27

Fundamentally, water is water. In its purest form, it is the same anywhere, except perhaps for the isotopes. However, one of the wonderful things about water is the fact that it's a good solvent, and in fact has many things in it that aren't water. For instance, one could not survive off of ocean water: we humans require fresh water. The one potential ...


24

We know from the nuclear power industry that spent fuel storage pools are pretty safe places to be around, radiation-wise. They're actually safe to swim in, to a point, because they're serviced routinely by human divers. They just can't get too close to the spent fuel. We use these pools for short-term storage because water is a really good radiation shield....


23

In addition to capture of contaminants, such as dead skin, hair, sweat, etc, and abrasion/cut protection, clothing forms a basic thermal layer that allows the human body to better regulate its internal temperature and perceived comfort level. Every human has variations in temperature, and even in a perfectly controlled environment once you place two humans ...


16

1) Startup cost. Buying and converting a boat is much more complicated and time consuming than pouring some concrete and welding some steel. 2) Logistics. You will need at least 2 boats. One as the launcher and one as the command centre. You also need to have a reliable comms link to the rocket. You also need to house the personnel and maintain both boats. ...


16

Most US Launchers use a similar water suppression system for the same reasons as the Space shuttle. At some level, if you intend to launch often you do not wish your launcher to destroy the launch pad. A rocket launching usually has between 600,000 lbs thrust (Delta 4's single RS-68) to 7 million lbs thrust (Space Shuttle, or Saturn V range) and that is an ...


16

Capsules like Apollo and Orion are mainly open space internally (the crew cabin); they have no problem floating by themselves (like a metal-hulled boat would). The conical capsule shape by itself will float in either of two orientations: stable 1 (base down, nose up) and stable 2 (nose down). In stable 2, the crew is hanging upside down in their seats and ...


16

Canals on Mars has quite an interesting history, starting with Giovanni Schiaparell. He produced this map of Mars in 1877 It is interesting to compare this map to a more modern map Note that the same general features are labeled, however, the lines that run between them don't show up at the modern image. Giovanni was Italian, and called the lines on these ...


16

Cassini's INMS, the Ion Neutral Mass Spectrometer, is an in situ instrument that measures the neutral and plasma gas composition of what it ingests. It was intended for the measurement of Titan's atmosphere, Saturn's magnetosphere plasma, ring composition, and in fact the composition of icy satellite effluents. Here is a good presentation on the basics of ...


14

We don't know yet exactly what caused it, but all tests so far ruled out everything else but the PLSS (Portable Life Support Unit). In fact, just today (Aug. 27, 2013) Chris Cassidy and Luca Parmitano managed to recreate the water leak that terminated EVA-23: Robotics, Science and Spacesuit Tests Aboard Station - Aug. 27, 2013: Flight Engineer Chris ...


13

Depends how you look at it. Onboard the International Space Station (ISS), water is definitely a precious resource and several measures were taken to consume less of it, such as recycling as much of it as possible, not washing clothes, reducing tap pressure, conserving it under shower and using wet cloths, using liquid waste vacuum tube on toilets, and so on....


13

No the blast clearing technique would not work, it requires gravity and the closed environment filled with one substance (water) of the snorkel to work. Neither are present in Luca's situation. Tidalwave's Video links in his comment, indicate that attempts to blow or shake the water away were counter productive, resulting in water entering Luca's ears ...


13

Indeed the presence of water has been confirmed. The late 1980s mission Giotto confirmed the existence of water on a comet well-known to mankind - Halley's Comet. Wikipedia states: Measured volume of material ejected by Halley 80% water, 10% carbon monoxide 2.5% A mix of methane and ammonia. Other hydrocarbons, iron, and sodium were ...


13

A picture might be worth a thousand words. Just imagine this situation without clothes:


12

I'll have to dig through the decadal survey and LPI proceedings a few times, so I decided I have to make this answer a community wiki anyway. As soon as there is a decent answer by anybody else, I'll accept it. Three basic mission modes: getting inside the ocean getting onto the surface doing research from low orbit The main goal: determining habitability ...


11

Depending on exactly what temperature the water on Enceladus is, the answer is yes. Bacteria are an obvious choice. But there is a higher lifeform which can almost certainly survive: Tardigrades (Water bears) can survive for days at −200 °C - longer at higher temperatures, and can cope with extremely acid or alkaline environments. They can even survive in ...


11

In fact, the Soyuz is designed to make an emergency water landing, and has done so once by accident, when Soyuz 23 landed by accident on a frozen lake. The landing didn't go particularly well, the parachute filled with water and caused the escape hatch to be covered in water. A complete account can be found here, but let's just say the experience was less ...


11

Shortly after this question was asked, it was answered (in the case of the moon, not Mars) on XKCD's what-if. Summarizing that article, for most average people swimming would be the same, as the buoyancy effects are an order of magnitude more dominant than the gravitational effects. Extraordinarily skilled swimmers would notice small difference, but the ...


11

Plants don't just need carbon dioxide; like most organisms, they need oxygen to survive as well. They can produce oxygen from carbon dioxide, but that doesn't help cells that aren't exposed to sunlight; if you put a plant in a very low-oxygen environment, it will die. There are organisms that can survive on little to no oxygen (e.g. cyanobacteria, which can ...


11

I guess the generic answer for any mass separation system would be that you spin it, but mass separation isn't really effective for electrolysis since that requires larger separation between anode and cathode which leads to protonic ohmic losses, i.e. increased internal resistance. So a more optimal species separation is done not by their mass but by their ...


11

The ball of water in that picture is in orbit; it's just surrounded by (presumably) the ISS. But a ball of water like that definitely cannot survive in the vacuum of space. Below a certain pressure, water can only be water vapor or ice. So a ball like that would immediately start to boil if it were surrounded by a vacuum. The water vapor would quickly ...


10

The major reasons for Sea Launch's approach is to be able to launch on the equator, and not to have to worry about overflying any territory, where stages might drop. The cooling aspect is probably the least interesting part. But the main argument against it is the infrastructure costs, and salt water corrodes everything, it would seem. No matter how well ...


10

Probably the closest thing to that environment on Earth would be Lake Vostok, which is 4 kilometers below the antarctic surface. Very little, if any, light gets down there, and it's really really cold, but still liquid. Scientists recently found bacteria living there, so it stands to reason that bacteria would survive on Enceladus, but the really amazing ...


10

Edgar Andreas made a nice chart for water sublimation in a vacuum at various temperatures: At 270 K it looks like a square centimeter of water ice surface sublimates 100 grams per hour. A typical snow flake masses 3 milligrams. Unless the snowflakes were cryogenic, they'd quickly sublimate Root square mean speed of water molecules at 270 K would be ~.618 ...


10

Ice sublimates. So does rock. Yet the planet Mercury is still there. The reason Mercury still exists is because even though rock does indeed sublimate, the rate at which rock sublimates is extremely low, even at temperatures at the surface of Mercury. The same applies to water ice at the very low temperatures in those permanently shadowed craters on the ...


9

Yes, and we are. The focus now is on the four ingredients for life, raw materials, energy, water, and favorable conditions. Water is always there, but is not the primary focus. We now seem to be able to find places on Mars where water once flowed using orbital data. It is the job of the surface missions to first confirm that (Curiosity has) and then look ...


9

Based on your comment stating you're question is irrespective of if the water is liquid/snow etc. I'd suggest reading about tungsten dust. Tungsten dust has been proposed as a solution to this problem, in fact you can even read the patent for it. The general concept is to release a collection of tungsten dust into a specific orbit to more quickly de-orbit ...


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