Questions tagged [design-alternative]
Questions about alternative designs the asker has thought of, such as "why was X built this way and not this way"
322 questions
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In retrospect, should they have provided more RTG fuel and a more powerful radio for Voyager?
Adding extra RTG fuel disks would increase the weight of the entire vessel only slightly, but give it a much, much longer lifetime.
It would also allow for the instruments to still be running, and for ...
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Why do you even need a heatshield - why not just cool the re-entry surfaces from inside?
Is it conceivable to instead of having a heatshield, to just have some sort of material or mechanism on the inside, that can convert the heat into something else?
A back of napkin calculation shows ...
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Is it possible to construct a way to breathe in space without a helmet?
Why you can't just go to space in a dive suit with some additional cooling. In fact what if you had the equivalent of a snorkel for breathing and a ski-mask type visor, well insulated to avoid ...
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Could inflatable habitats be used on an artificial gravity station?
If you take an inflatable module such as the Sierra Space's LIFE, could you arrange them all around the ring of an artificial gravity station? My main question here is regarding the structural ...
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A Mars Sample Return Misson Profile
The first and second modules are both launched to Earth's Orbit. Their iodine ion engines get them on their way to Mars. The first module is in a free return trajectory. The second module is in a ...
user57372
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Could we convert lunar regolith into a trinitite landing pad with an atomic weapon?
My thinking here is that a modern thermonuclear weapon would not weigh very much and that by detonating one an appropriate distance above the lunar surface, the regolith could be melted into a hard ...
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Which rocket engines used this exotic cycle?
A "Hypergolic, Full Flow, and Closed Catalyst" cycle
Left side:
All hydrazine goes through the centrifugal fuel pump
All hydrazine goes through thermal decomposition
Out of it comes hot ...
user57372
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Diagonal ice tunneling rover to reach a safe pressure in Mars?
Is the ice on Mars deep enough to bore down into it to sustain around 10 PSI (69 kPa) air pressure? The device I have in mind is a rover with a reactor that melts through the ice slowly to create a ...
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Reducing required length of a mass driver using loop?
If you had a loop of electromagnets with an encapsulated payload inside vacuum tubes, how fast could you accelerate the capsule to before it reached some maximum velocity?
What effect would scale have ...
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Open air dock to space in a rotating space station?
Suppose you had a very large pipe, say 20 meters in diameter, open to space at the hub of a spinning station, and leading off radially from the hub towards the rim, where the pipe is sealed. After ...
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Could Kessler Syndrome be used to control the temperature of the Earth?
Imagine launching a bunch of tiny reflective particles in orbit. This would reflect sun away from earth. Based on the orbit, you could have a swarm only go over certain parts of the earth. Or only ...
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Has anyone proposed a mission to catch an small asteroid?
The idea here is that you launch a platform into perhaps a medium earth orbit. That platform is equipped with a radar system and an interceptor missile. When the radar detects an asteroid of the ...
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Permanent living on Maglev train on the Moon as a colony
NASA is considering a proposal to build a levitating train system on the Moon.
The Moon's surface is often flat and smooth. Maybe building a mobile train colony similar to the movie Snowpiercer on the ...
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Why do cryogenic fuels want an extra pressure tank?
I do see the need to provide pressurizing gas with non cryogenic fuels (like RP-1) but if you require to have it at very low temperatures anyway to keep it liquid and the pressure in the tank drops, ...
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Exploring DNA-Based Hard Structures for Space Applications—Looking to learn more
I recently had a fascinating conversation with a student about to graduate with a master's in microbiology. He shared that he’s lined up a job where he'll work on developing "hard structures"...
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Choice of Ammonia and oxygen as liquid rocket propellants in vortex combustion
I have been thinking lately about the benefits of using liquid ammonia and oxygen as rocket propellants, where ammonia is difficult to burn, what if in a fuel rich closed cycle, ammonia is used to ...
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Using Orbital Rings to Achieve High Escape Velocity
Hoping an astrophysics-calculation-competent person could help confirm this scenario:
Say civilization has established an orbital ring around the Earth with an external launch track (using super-...
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Can infrastructure for generating a protective artificial magnetic field around a planet also be used to propel nearby spacecraft?
This is an attempt at "...maybe you scientists whizzes can visualize what I'm talking about and explain it better." from this closed question.
If a well-established colony on the Moon or ...
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Could we make space roads? Like a space elevator between planets?
We hear a lot about space elevators that could place something in orbit, but what about a space road between planets? Suppose you had a long tube or flat road placed between Earth and Mars by chemical ...
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Solar Reflective Plasma Drive
I understand that solar sails have just recently been progressing to be of use. Could the solar sails be positioned to create a hyperbolic mirror to super heat a substance to produce propulsion along ...
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Why not use containers to clean up small space debris?
Small space debris is a serious problem. I think that if a large container orbits full of space debris and sweeps up small pieces of space debris that fit into the container, the space debris can be ...
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Tether materials considerations for sky hook with jet engine
Suppose a skyhook was deployed with orbital dynamics mechanics such that when its hook side (opposite the counterweight) entered the atmosphere, it was nearly stationary with respect to local air ...
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Would (Dual Concentric inline Powerhead) FFSC Cycle engine be possible to engineer
I,ve been wondering if it was possible engineer and how we would we work it out DUAL preburner inline FFSCC ENGINE with concentric core and individual concentric turbine inside one another and maybe ...
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Could a rotating skyhook use a sail or wing to make orbital corrections to keep the structure in orbit?
Imagine a rotating skyhook with the majority of its length in the thermosphere, but whose hook side (as opposed to the counterweight side) has the ability to deploy wings or sails. Suppose that ...
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An alternative architecture for a mission to Mars
This image, which is supposed to represent the current architecture of the mission to Mars by NASA, raised a wave of emotions. People find it too long and complicated. But is it really possible to ...
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What can possibly accelerate space elevator to these types of extreme velocities?
Is it possible for a space elevator not to just reach speeds of a few hundred km/h, but much faster. Since in the future, people might want to go up to GEO to maybe work there and come back home on ...
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connecting two satellites [closed]
How strong would my bond have to be if I wanted to closely connect (30cm - 1m link) two satellites on the same orbit in LEO? (I can move the satellites however I want to have them close to each other)
...
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Misting/Fogging Nozzles as Rocket Injectors
Misting and Fogging Nozzles are nozzles often used in irrigation and cooling. They basically use high pressure to break the liquid into tiny droplets achieving really great atomization. I think these ...
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In Zero G, can excess heat be used propel a spaceship forward?
In Zero G, can excess heat be used propel a spaceship forward?
I was looking for a similar answers online, and have bounced around a few places, I found this question, and it's responses thread useful ...
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What conferences have technical sessions that cover credible and transformative alternatives to chemical-rocket-based launch?
Constraints
Some examples of such technologies are described on Wikipedia's Non-Rocket Spacelaunch page. But, to clarify a bit further...
I found list of such technologies in Figure 2.1 of a document ...
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Shuttle-era mission profile for a desperation moon mission
It is 1996. For reasons best left to Worldbuilding SE, it has become a matter of civilizational life and death to send humans to the moon and bring them back to earth as soon as possible. Everybody is ...
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Embedding foundations from low lunar orbit?
Reading about Lunar Crater Radio Telescope and Lunar regolith thickness and composition,
(roughly 5-10m of soft soil) and anchoring in soft regolith, would it make sense, in order to anchor large ...
user19132
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Solar Turbines on the moon
Related to other questions about power generation on the moon.
URL's will be added shortly...
Given that force is experienced by objects hit by sunlight, such as a solar sail, would a turbine of some ...
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Hydrogen-propelled space elevator [closed]
I'm working on a space elevator design using kerosene-burning jet engines and dirigibles supporting 1km stages of pipeline and cable stretching up to the end of the stratosphere (~50km), then using ...
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Windmills in Space [closed]
What if we put a windmill like we use now in space like on moon or a space station so its attached to the surface and since we have no wind we use air tanks in the blades to rotate, everytime it slows ...
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Deorbit ISS vs. Preserve ISS as raw materials for ISM?
Recent news:
NASA Seeks Proposals from US Industry for Station Deorbit Spacecraft (ISS)
NASA has released a request for proposal from U.S. industry for the U.S. Deorbit Vehicle (USDV), a spacecraft ...
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Would orbital ring platforms affect the orbit of a planet?
If we built an orbiting platform of sufficient mass (let's say, made from harvested asteroids) that was anchored at both poles of the planet it surrounded, would such an addition to the planet's mass ...
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How does SpaceX prevent fuel from cluttering together in zero G [closed]
What is the solution to stop fuel inside starship collecting in center of the tank during zero G flight? Here is a rough sketch of starship with rudimentary diaphragm system to control flow of fuel ...
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Could a skyhook with double pendulum catch a payload with zero velocity?
It's my understanding the the tip of a rotating skyhook would be travelling at ~3.6 km/s (Mach 10), which presents a major problem.
Could this be overcome by attaching a second, smaller, also rotating ...
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Semi-Cryogenic HTP/LH2 engine?
Also see HTP as oxidizer for main propulsion
(for more info on history of H2O2/HTP in rocketry)
Note: HTP and H2O2 will be used interchangeably
I know the Black Arrow LV (The first orbital lipstick) ...
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space is a vacuum there is no drag, so would hydrogen harvesting from space to use as fuel be possible once in orbit? [closed]
If space is a vacuum and there is no drag, would hydrogen harvesting from space to use as fuel be possible?
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Inflatable tank/balloon use for recovery
Hopefully this idea makes sense.
Basically if you've seen the space-truck (ROOST), you'll get where I'm going with this.
I'm wondering whether an inflatable tank/tank lining could be used to produce ...
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Would a laser seismometer work from lunar orbit?
Lasers today have become extremely sensible, they can detect sub-millimeter movements of a surface from a distance. Could this feature be exploited to create a lunar seismometer working from a probe ...
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SSME/RS-25: why seal between LOX pump and preburner?
Both the the fuel and oxidiser preburners ran fuel rich. In order to prevent the preburner gas from entering the LOX pump and blowing it up, they had this complex double seal with a gas purged void in ...
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Higher density medium tube from sea level to space for travel
Is it theoretically possible to build a strong sealed tube from Earth's sea level all the way to Space, fill it with a medium (such as water) that has a higher density than humans. And then humans ...
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Why can't buoyancy of air be used to support a mega structure as an alternative to a space elevator?
The reason for asking this question stems from recent articles about large loss of strength of carbon nano tubes with even single atom movement, tested samples showing high vulnerability to space ...
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Wouldn't it make sense to use parachutes for aborting test flights rather than destroying the whole rocket?
Recently, a SpaceX test flight was aborted by blasting the whole device.
Wouldn't it make sense to have parts of such rocket be equipped with parachutes when test flights are performed, so at least ...
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Why wasn't Buran mounted on top of Energia?
Since unlike the Shuttle, the Buran did not carry the main engines, why was it not mounted on top of the external tank equivalent - Energia's core stage?
And even better, why wasn't Energia's second ...
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Why didn’t the N1 use detachable boosters like the Soviet’s did on Soyuz?
Why did the N1 (to my inexperienced eye) have a massive rework? Soyuz, Vokshod, Vostok, Sputnik all showed that detachable side boosters worked. If side boosters work, why wouldn’t the N1 just had ...
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If a spacecraft's double hull filled with water is hit by a micrometeorite, could the water freezing or surface tension stop the leak?
I'm thinking about the possibilities of water storage also serving radiation shielding for long space journeys (months to years).
Assume within the solar system but outside of upper earth orbit. ...
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