Questions tagged [vacuum]
Questions regarding the effects and conditions in a 'partial vacuum' or space with a gaseous pressure significantly smaller than atmospheric pressure.
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Why is the expansion ratio of the nozzle of the 2nd stage larger than the expansion ratio of the nozzle of the 1st stage of a rocket?
As an answer I have two statements, which statement is correct? If one or both are wrong, can you please provide me an explanation?
Statement 1:
The goal is to achieve maximum efficiency in thrust. ...
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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, ...
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Lorentz force space propulsion
While browsing for Space propulsion, I've found the following article
As shown in Figure 2, the conductor I0 gets through the coil L0, and they are fixed together and form a system. a is the main ...
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How to repressurize a vacuum chamber really fast?
There was an accident during a suit test in a vacuum chamber on December 14, 1966. The suit lost pressure and
The chamber – which would normally take 30 minutes to repressurized –
was blasted back to ...
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Vacuum chamber incident during apollo preparation
I've heard of an incident in the mid 60s: someone was testing a space suit in an vacuum chamber, the suit depressurized and the man fainted after feeling the water in his mouth begin to boil.
It's a ...
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Does the Merlin vacuum engine on SpaceX's Falcon 9 gimbal?
SpaceX uses the Merlin Vacuum engine on the second stage of the Falcon 9 launch vehicle. Does the merlin vacuum engine gimbal or does the second stage uses only nitrogen cold gas thrusters for ...
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How do you test-fire vacuum engines in a vacuum chamber? Why doesn't it fill up almost instantly from the exhaust and spray (deluge) water?
How are vacuum optimized engines tested without disintegrating them? is an excellent question as it's attracted quite a number of informative and diverse answers.
@Uwe's answer informs us that there ...
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How unusual is it to test vacuum engines at sea level?
How are vacuum optimized engines tested without disintegrating them? is an excellent question as it's attracted quite a number of informative and diverse answers.
@Uwe's answer informs us that there ...
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How are vacuum optimized engines tested without disintegrating them?
SpaceX recently test fired vacuum optimized raptor engines of starship. Doesn't vacuum optimized engines disintegrate when operated in atmosphere? If yes, what additional modifications are made to the ...
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How do the roll-rings at the ISS work?
I get that on the ISS they need to keep the solar panels constantly rotating to keep them looking towards the sun.
To transmit the electricity and data to and from the Solar panels truss structure ...
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If an astronaut threw a cup of coffee into space, would it freeze, or boil off into gas?
If an astronaut threw a cup of coffee into space somehow, would it freeze into a block, or boil off into gas due to the zero pressure?
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Would a spaceplane be able to softly land on an airless planet?
Assuming the spaceplane has no vertical (hover)engines, is there a possibility to land a spaceplane on a celestial body without atmosphere in a horizontal way as if it had one? One could lower the ...
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What happens if the inner door of a depressurised airlock fails?
What are the consequences of the INNER door of a spaceship airlock system suddenly failing (for whatever reason) when the airlock itself is depressurised? (The ship itself is in space/vacuum and not ...
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What are these white garbage-like things on Falcon 9 vacuum engine? [duplicate]
On recent launch I noticed, that some white things jumping on vacuum engine in space. Something like garbage or condensate. See video at right at times when Earth is at left:
...
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How rover landing is achieved on planets with very low atmospheric pressure?
I would like to understand how safe landing of a rover is achieved on mars or any other planet where the pressure is very low. Is it achieved by releasing gas from high pressure to low pressure. I ...
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Are galvanised steel parts safe to use in space?
Are galvanised steel parts safe to use in space (high-vacuum environment), e.g. washers, fasteners, nuts? I've heard that zinc can sublimate at low pressures.
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Why use nozzle extensions for ULA's Vulcan; why not make them this long in the first place?
This answer to What is the difference between the Vulcan 562 configuration and the Vulcan 5H2 ("Heavy") configuration? explains that the 2nd stage nozzles were modified by extending them, ...
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Purpose of foil on Merlin Vacuum Engines of SpaceX
I want to know what is the purpose of this silvery foil situated above the bell in Merlin Vacuum Engines, and what purpose does it fulfill exactly?
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What would happen if you jumped out of a moving spacecraft?
I've watched a film where one of the characters claimed to have rapidly disembarked a moving spacecraft during a 5g burn (?!) and immediately wondered how he survived.
For example, you're on a ...
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Do vacuum-grade oils and greases trivially solve the "lubricants don't work in space, cold welding happens" problem (for short to moderate duration)?
(Related: How is the unwanted cold welding prevented in space?)
I've often seen talk about fairly simple mechanical devices (hand tools, simple handheld power tools, firearms, etc) being unlikely to ...
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Was the ship decompression scene in the movie Aliens realistic?
I was directed here from Sci-Fi SE to pose this question.
Towards the end of the Aliens (1986) movie, Ripley is forced to override the clearly marked "outer door" control having already ...
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Why do spacesuits have air in the body? [duplicate]
Wouldn’t it be easier to make a space suit that only maintains air around the head, and just has a “tight” insulated and shielded suit around the body?
It seems to me the reasons we need a space ...
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Can we create a vacuum inside an EVA suit when the outside is pressurized, will it implode?
EVA suits are specially designed spacecrafts for astronauts during spacewalks. I can say for sure, it can handle the following cases of pressurization of the system:
Pressurized inside, but vacuum ...
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A question about the feasibility of the Casimir propulsion system [closed]
There is a connection between vacuum energy density and the Casimir effect , see :
https://arxiv.org/abs/quant-ph/0204125
Another reference can be found here:
https://aapt.scitation.org/doi/10.1119/...
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Why were some early interplanetary probes pressurized?
Mariners 2 through 9, and the Soviet spacecraft of that era, sometimes suffered from leaks that impaired or disabled parts of their scientific payloads.
What kinds of sensors couldn't work in vacuum? ...
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Was there a measurable effect on gas concentration on the Moon during the Apollo missions?
Gas was released by the Apollo Lunar Modules during depressurization of the cabin in preparation to an EVA.
Did this release of oxygen had a measurable effect despite the small amount of gas and the ...
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Exit pressure value for vacuum nozzle [duplicate]
What value of exit pressure should I use in the design equations for a small liquid rocket engine nozzle for 200km-500km operating conditions?
Since using zero as a value is not possible or else ...
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Ambient pressure for vaccum nozzle design
How do I find out the ambient pressure for designing a vaccum rocket engine?
I am using the propellant combustion charts from the braeunig website. But I cannot figure out the ambient pressure for ...
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What is the vapor pressure limit of liquid metals in space?
Would liquid metal be stable in space unlike most other liquids like water? Are there any metals that has a high vapor pressure limit?
Side question: Can liquid metal be given an electromagnetic ...
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Spacesuit needed for 1 psi 100% methane atmosphere - 60 Fahrenheit?
What sort of spacesuit would an astronaut need if she were to walk on a planet with a 1 psi (0.07 ATM) 100% methane atmosphere and -60°F (-50°C) temperatures?
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Can I freshen my clothes on the ISS with a clothes line?
There are a number of questions about washing clothes on the ISS, the short answer is that they do NOT wash them.
Nudism in space: Why wear clothes anyway?
Washing clothes in space: are there any ...
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What is currently known as the thinnest combination of material to hold 1 atm in space?
What is currently known as the thinnest combination of material to hold 1 atm in space?
Note: must define what the composing materials are.
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Nozzle skirt in the second stage of Rocketlab's Electron [duplicate]
As we can see, in the first stage of Rocketlab's Electron the nozzles have small nozzle exit area.
Source (all)
But for second stage why are they using nozzle skirt/ extension with huge exit area?
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How far/much time could a fleshy appendage extend outside of the ISS before succumbing to severe damage?
I was reading the question asked here in regards the Alexander Gerst's patching of a small (5mm) hole with his thumb temporarily. This got me wondering, if his thumb was only fine because the majority ...
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How come we don’t put a huge windmill-like machine in space? [closed]
I am new to this sight, but since space being a vacuum there is little to no air resistance at all making a windmill spin forever. There is no wind in space however, if you spin it once, it should ...
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Pool on the Moon?
Hypothetical scenario: There is a dome on the moon containing an Olympic-size swimming pool. Our intrepid hero is receiving a scuba diving lesson at the bottom of the pool (3m) when a hull breach ...
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Cooking in Space
Someone in the Worldbuilding SE asked How to Build a BBQ for the ISS.
My first through was: Why not just stick it in a sealed container out in direct sunlight for a bit? It'll get plenty cooked ...
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In the absolute vacuum of Space, will an electric dynamo still work? [duplicate]
In the absolute vacuum of Space, will an electric dynamo still work? Can it produce an electric current if it is not inside (or being affected by) a magnetic field (like earth's magnetosphere)?
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What type of electrical wiring provides the longest life in space?
It sound like standard electrical wire as you would use in earth bound transportation would have a significantly shorter life in the vacuum of space. (See related Do plasticizers evaporate in space?) ...
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Do plasticizers evaporate in space?
A recent statement in an answer got me wondering. I looked and could not find an answer on space.se
Polymers (think plastic cladding on wires) has "plasticizers", which make it elastic instead of ...
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Mars Vacuum-blimp Feasability
There's an article published by NASA in which they discuss the practicality of using an evacuated blimp or airship on Mars. Their main points are that since the exterior pressure is so much lower, ...
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Could there be any use with importing vacuum from space to Earth?
Space exploration pessimists say that there's nothing to import from space to Earth. So why not begin with doing exactly that?! :-)
It's commonly claimed that the vacuum of space is harder (emptier) ...
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Flight Suit Pressurization
I'm curious about the pressurization of a full pressure flight suit (such as). For example, the linked suit has an operating pressure of 3.5 psi, but my assumption would be that during normal flight ...
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near space vacuum balloon
OK we know that due to air pressure a vacuum balloon would not be possible on earth.
But would it be possible to create one that floated near space with almost no air pressure?
If so how much ...
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How are electrical and other utilities interfaces added to an operating pressurised spacecraft?
How are extra utility lines and pipes, like data, electrical, ?or gasses and fluids, added to a manned, pressurised and operating vehicle or habitat, in space?
A spacecraft may be launched with, ...
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What is the ring at the bottom of the Merlin vacuum engine?
When watching SpaceX launches, around 2-3 seconds after the Merlin Vacuum ignition a ring can be seen breaking in 2 from the bottom of the nozzle and then falling away from the second stage. My ...
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Do electronics and mechanical components work in a vacuum or require a sealed controlled atmosphere?
I'm curious about the electronics and other instruments on Voyager and similar spacecraft. Are the electronic components kept in open vacuum or in a sealed atmosphere? I imagine cooling gets tricky ...
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Why does there appear to be a 180-degree stereo microphone array outside the ISS?
I was watching a feed on the latest footage of Hurricane Matthew as seen from the ISS just now, relayed from NASA TV. Suddenly, I spotted something poking out of the ISS hull in the footage that ...
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Has any living thing been directly exposed to the vacuum of space
In our several decades of spaceflight have we ever exposed any living organism to space? I'm pretty sure this hasn't happened to Humans, but have we jettisoned some lab rats into space ("for science") ...
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What happens to a body, that has been exposed to vacuum, once brought back onboard?
You are on a ship in the cold vacuum of space. You find a body of an astronaut exposed to vacuum (for this instance just assume human, but you never know).
The body was essentially freeze dried and ...
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