Skip to main content

Questions tagged [oxygen]

Questions regarding consumption and production of oxygen

Filter by
Sorted by
Tagged with
24 votes
2 answers
6k views

Why aren't spacecraft and spacesuits pressurised to 2.5 psi (17 kPa) of pure oxygen?

Today 1 atm (101.3 kPa, 14.7 psi) with sea level composition is most commonly used on spacecraft to avoid fire hazards like in Apollo 1 (not that it would have helped the Apollo 1 crew as they couldn'...
user avatar
23 votes
3 answers
7k views

Why would oxygen be stored as a super critical fluid?

Organic Marble just answered a question about Apollo 13 in terms of the storage of Oxygen, and posted some fascinating stuff, including the fact that Oxygen was stored as a super-critical fluid. I ...
Magic Octopus Urn's user avatar
22 votes
4 answers
6k views

Oxygen self-supply by plants

Plants produce oxygen, we know. This might make plants useful in the supply system of possible colonies on other planets or moons. But how efficient they are? Which is the maximum amount of oxygens ...
Zoltán Schmidt's user avatar
20 votes
5 answers
2k views

Is atmospheric skimming for propellant feasible?

A recent comment in a discussion of satellite refueling mentioned the possiblity of a spacecraft dipping into the atmosphere from LEO to obtain oxygen. Similarly, the science fiction RPG Traveller ...
Russell Borogove's user avatar
18 votes
4 answers
4k views

What stages of distress occur to a person when there is a small hull breach in space?

I'm working on a short sci-fi game and I'm curious about how the effects of a hull breach in a confined area play out. For perspective, let's say a very confined space of 100 cubic feet of normal, ...
HAL 9000's user avatar
  • 181
16 votes
2 answers
8k views

What does "stirring tanks" mean?

The Apollo 13 disaster occurred right when the "oxygen tanks were stirred". What does that mean? What benefits does it give? What would happen if they didn't stir the tanks?
Bohemian's user avatar
  • 817
16 votes
2 answers
5k views

Are there any short-term survivable locations in the solar system, outside of Earth?

Are there any known natural locations (i.e. not counting ISS) in our solar system (outside of Earth) where a human being in street clothes (i.e. without a spacesuit or other specialized equipment) ...
Jeremy Friesner's user avatar
15 votes
5 answers
3k views

What concentration of oxygen in a planetary atmosphere would be indicative of life?

Astronomical spectroscopy can be used to determine the chemical composition of distant bodies. In the related question Can we detect atmosphere on exoplanets? we learned that, even now, we are ...
James Jenkins's user avatar
15 votes
1 answer
2k views

What is the advantage of using Helium over Nitrogen when used for pressurising LOx?

In this Twitter post of the plumbing line diagram(left half) by LauncherSpace, one can notice that Helium is used for pressurising LOx while Nitrogen is used for pressurising Kerosene. Why the ...
karthikeyan's user avatar
  • 4,469
15 votes
2 answers
2k views

How long were the Apollo astronauts allowed to breathe 100% oxygen at 1 atmosphere continuously?

This answer explains that from the time they suited up "in the Suit Lab before launch" until the time the capsule started depressurizing during ascent, the Apollo astronauts were breathing 100% oxygen ...
uhoh's user avatar
  • 149k
15 votes
1 answer
2k views

How do they conduct electrolysis in zero gravity?

I'm building an electrolysis cell myself, and got to wondering. On Earth, there is a significant force pushing bubbles of hydrogen and oxygen upward, so your electrodes still contact mainly water. ...
BWG's user avatar
  • 295
14 votes
4 answers
4k views

Do rockets deplete the oxygen on earth?

When we use our rockets in space, are we using up a fraction of the finite oxygen here on earth? I'm assuming that it's a negligible amount at our current rate of space travel, but could this ...
Sid's user avatar
  • 243
14 votes
2 answers
4k views

Why is the EMU space suit pressurized to 4.3 psi specifically?

Wikipedia claims that space suits that use pure oxygen are pressurized to 4.7 psi, instead of 3.0 psi, to account for carbon dioxide and water vapor pressure as per the alveolar gas equation (although ...
Nakedible's user avatar
  • 855
14 votes
1 answer
1k views

How does it feel to breathe 100% oxygen at low pressure?

Some space suits are designed to provide an atmosphere of 100% oxygen but at a reduced air pressure about 20% that of sea level. Is breathing in such a suit uncomfortable? It seems like having such a ...
Cory Klein's user avatar
13 votes
2 answers
672 views

Decision Factors for using 100% $ O_2 $ cabin atmosphere in early US space program

What are the reasons for deciding to use a 100% $ O_2 $ cabin atmosphere in the early US space programme? Was danger of nitrogen narcossis a factor? Did all missions prior to Apollo 1 use a 100% $ ...
My Other Head's user avatar
12 votes
4 answers
6k views

Is oxygen present in the sun? [closed]

If there is no oxygen in the sun, then how is it burning? My question may be weird but I need a realistic answer for that.
user20760's user avatar
  • 121
11 votes
2 answers
702 views

Why is the surface of Mars oxidized?

Before 2.5 to 2Gya, Earth's surface was a chemically reducing environment (evidence includes reduced forms of iron, sulfur, and uranium in rocks before that time). It is believed to have become ...
Dr. G's user avatar
  • 111
11 votes
1 answer
1k views

Function of the RL10 Oxygen Turbopump's Splined Shaft End

The oxygen turbopump in the RL10 upper stage engine has been openly discussed by NASA for some decades now, in publications like SP-8107. On page 8 of this document is a drawing of this turbopump. The ...
Rikki-Tikki-Tavi's user avatar
10 votes
2 answers
1k views

Self-sustainable Hermetically Sealed System: Humans & Plants

Somewhat related to How many plants would be needed to produce oxygen enough for 20 humans? Suppose a number of humans are closed in a large hermetically sealed room on Earth with a glass (or other ...
Jan Stuller's user avatar
10 votes
2 answers
696 views

Are there enough oxygen molecules in space that they could be compressed into breathable oxygen?

There is stuff floating around in space - everything from asteroids to planets to molecules. I was thinking - would it be possible to harvest stray oxygen molecules, compress them, and get breathable ...
user avatar
10 votes
2 answers
2k views

What is required to produce rocket quality methane fuel and oxygen from Mars' atmosphere?

Turning $\require{mhchem}\ce{CO2}$ and some hydrogen into $\ce{O2}$ and $\ce{CH4}$ seems pretty straightforward and has been known since early chemistry in the 19th century. But what about the quality,...
LocalFluff's user avatar
10 votes
1 answer
8k views

How much oxygen and hydrogen are in the soil of Mars?

Current knowledge suggests there is plentiful water ice at the Martian poles. The same knowledge says it gets cold enough at the poles for carbon dioxide to freeze out of the air. If creating a ...
James Jenkins's user avatar
9 votes
1 answer
210 views

Has solidifying liquid propellant been considered for space exploration?

Liquid hydrogen is $0.071 g/cm^3$ Solid hydrogen is $0.086 g/cm^3$ Since denser fuel is desirable, has solid hydrogen been considered for use in space exploration? I suspect the very low ...
Antzi's user avatar
  • 12.6k
9 votes
1 answer
370 views

Is the hybrid sulfur cycle a good way of making hydrogen and oxygen on Venus?

Assuming we collect sulfuric acid from Venus clouds using some sort of airship, what would be the best way of turning this into hydrogen and oxygen? I came across something called the hybrid sulfur ...
Erik Engheim's user avatar
8 votes
2 answers
2k views

Can a machine process and run on $CO_2$ and $H_2O$ for an $O_2$ by product?

On Mars studies have shown that carbon dioxide solidifies to dry ice at the poles. During the winter months can electrolysis be applied to collected and then contained liquid $CO_2$ to replenish ...
Muze's user avatar
  • 1
8 votes
2 answers
3k views

Oxygen toxicity vs Apollo mission preparation

In the article on Apollo command module design, I read: The cabin atmosphere at launch was changed to 60% oxygen and 40% nitrogen at sea-level pressure: 14.7 psi (10.1 N/cm2). During ascent the cabin ...
SF.'s user avatar
  • 55k
8 votes
2 answers
1k views

How feasible is it to grow algae on Mars to use as food, plastic and oxygen production?

I am currently researching the idea of growing spirulina algae on Mars for as a renewable source of oxygen, food and material. So the question arises: How feasible would it be to grow spirulina in an ...
Awesomepotato29's user avatar
7 votes
2 answers
289 views

How much oxygen can MOXIE produce?

So MOXIE is using solid oxide electrolysis to produce Oxygen. I assume the amount of oxygen MOXIE can produce is limited so how much can it produce before the solid oxide electrolyzer cell stops ...
neubert's user avatar
  • 235
7 votes
1 answer
241 views

Iron Oxidation Mechanism on Mars

My question relates more to the possibilities of life on Mars than to mining mineral deposits. QUESTION: Is it possible to have oxidized iron in the quantities that we see on Mars with only available ...
John Brittain's user avatar
6 votes
1 answer
735 views

How much algae would you need to fully support a person?

Recently, I saw a video on Cody'sLab, where an “algae panel” was constructed. This is set up like a solar panel and uses algae to convert light and air into food and oxygen. This got me wondering how ...
Topcode's user avatar
  • 893
6 votes
1 answer
483 views

What effects did the different air pressure and air composition in certain spacecraft have on astronauts?

The Mercury and Gemini spacecraft, and in space the Apollo spacecraft, didn't pressurize their cockpits to 1 atm with Earth-like atmospheric composition; instead, they used pure oxygen at much lower ...
user avatar
6 votes
1 answer
697 views

How cryogenic oxygen was heated up for CM cabin repressurization?

In related question How was temperature and humidity maintained inside the Apollo mission capsules? the basic concept of conditioning Apollo mission capsules environment is described. After ...
Sergiy Lenzion's user avatar
6 votes
1 answer
2k views

Supply of liquid oxygen (LOX) maintained on the ISS? Kept cold using "space", or refrigerator?

One can transport and store oxygen more efficiently (volume and weight of tank) if it is liquid under the order of 1 atmosphere. Liquid oxygen (LOX) is kept cryogenic in insulated tanks for short ...
uhoh's user avatar
  • 149k
6 votes
2 answers
363 views

Where can I breathe for free? [closed]

There ain't no such thing as a free lunch was often a plot point in the works of Robert Heinlein, particularly in regards to air. We know that Air in International Space Station comes at price, in ...
James Jenkins's user avatar
6 votes
1 answer
550 views

Could the Moon be terraformed by outgassing its oxygen?

The majority of the Moon's mass is oxygen. With energy it could chemically be liberated from its silicon et cetera compounds and be turned into oxygen gas. Given its low gravity, lack of magnetosphere ...
LocalFluff's user avatar
5 votes
3 answers
332 views

What is the reason for a LACE rocket to dump fuel?

The concept of LACE sounds awesome, especially the part "fuel is hard to come by in the atmosphere but there's some oxidizer available". The inefficiency due to the heat exchange ...
Vorac's user avatar
  • 499
5 votes
2 answers
600 views

Oxygen for manned missions

What are some techniques/ways to provide enough oxygen for some manned mission that would last, say, years? edited I mean some arbitrary mission departing from earth to infinity and beyond... No ...
rodrigo-silveira's user avatar
5 votes
1 answer
326 views

How many square meters of solar panel to power a MOXIE-like oxygen source per person?

If I wanted to live in a box on Mars to write my screenplay about living in a box on Mars, how many square meters of solar panels would I need to power a MOXIE-like CO2-to-O2 converter in order to ...
uhoh's user avatar
  • 149k
4 votes
3 answers
2k views

Isn't electrolysis of water less efficient for a space craft than pressurized oxygen tanks?

Isn't electrolysis of water less efficient for a spacecraft than pressurized oxygen tanks? The ISS uses electrolysis but to do this you have to send water to space which weighs more than oxygen and ...
Aaron M's user avatar
  • 456
4 votes
1 answer
2k views

What are the odds of finding a lifeless planet with breathable air?

As I understand it, our current breathable atmosphere on Earth is the result of early lifeforms transforming huge amounts of CO2 into O2. Before early life, even Earth's atmosphere wasn't livable for ...
Nerrolken's user avatar
  • 467
4 votes
2 answers
281 views

In principle, could the oxygen tanks of an 'air breathing' rocket, be filled during ascent?

(Thinking of SABRE and it's heat exchanger). As I understand it, Skylon would take off with full oxygen tanks. Putting aside engineering difficulties, is there a thermodynamic reason why a hybrid ...
InkWiring's user avatar
4 votes
1 answer
439 views

Did the Space Shuttle crew have to worry about monatomic oxygen?

Comments below this answer tell us that the Space Shuttle always remained in Earth's atmosphere. When it visited the Hubble Space Telescope or the ISS or Mir it was still in the thermosphere and ...
uhoh's user avatar
  • 149k
4 votes
1 answer
176 views

Measuring Oxygen Quantity

How did the Apollo program measure Oxygen Quantity? The Command Module had a Pressure Gauge and a Quantity Guage for the oxygen bottles. Measuring pressure is simple, but I don't see how quantity is ...
James Rix's user avatar
4 votes
1 answer
176 views

Experience of breathing regular air vs. Nitrox vs pure oxygen at 4.3 psi?

Has any astronaut/cosmonaut described a difference in the feeling of breathing pure oxygen at 4.3 psi in a spacesuit compared breathing regular air at sea level or even to Nitrox used in the Neutral ...
Bob516's user avatar
  • 6,959
4 votes
1 answer
331 views

Could the sulfuric acid in the atmosphere of Venus be heated enough by concentrated sunlight to create water and oxygen?

The atmospheric pressure and temperature at about 50 to 60 km above the surface of Venus is nearly the same as that of the Earth, making its upper atmosphere the most Earth-like area in the Solar ...
Cornelis's user avatar
  • 7,535
4 votes
1 answer
1k views

How to produce oxygen out of Venusian atmosphere's carbon dioxide?

What are the possible methods of in-situ extraction of oxygen from the atmosphere of Venus, which is mostly carbon dioxide?
Keyla's user avatar
  • 53
4 votes
1 answer
292 views

How is CO₂ scrubbed from the air in a space vessel?

Within a space vessel such as the ISS for example, how do the astronauts regulate the level of CO₂ they are breathing and how is the air scrubbed exactly?
aitía's user avatar
  • 277
4 votes
1 answer
387 views

Can the cryogenic expansion of liquid oxygen and liquid hydrogen be used to pump a rocket engine?

A common fuel amongst rockets is that of the combination of cryogenic liquid hydrogen and liquid oxygen. I looked at the design of a simple rocket using this cocktail that is the propellant and found ...
Steve Mucci's user avatar
4 votes
2 answers
347 views

How is it proposed to extract oxygen from lunar regolith?

Futurism's news item NASA Pumps Funding into Startup That Says It Can Harvest Oxygen From Lunar Regolith says: NASA just awarded substantial funding to Pioneer Astronautics, a company that claims it ...
uhoh's user avatar
  • 149k
4 votes
1 answer
140 views

What transportation energy “currency” would be most suitable for mobile machinery on the Martian surface?

What transportation energy “currency” (methane, H2, electricity) would be most suitable for mobile machinery on the Martian surface? Photovoltaic (PV) cells or nuclear energy will likely be the only ...
Woody's user avatar
  • 22.1k