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^ Propulsion is too broad to cover in 3 minutes. Picking a specific process or system in propulsion (such as injectors) may be a possibility but, now you're running with a topic that is seemingly irrelevant against competitors. If your goal is to explain as much as possible, solar winds is the route. Solar radiation can be summed up in a few sentences. Your ...


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We don't know exactly how much krypton starlink satellites have, but some guesswork based on the orbital maneuvers performed says that they would need ~2.5 kg of fuel. See https://space.stackexchange.com/a/36471/40045 for more information.


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Here's how I see it: Spacecraft propulsion is an incredibly broad subject, and you might run into some issues when putting it into a 3 min video. Gravitational time dilation is really a stroke of genius on Einstein's part, and has to do with some fairly complex 4D math to do with spacetime. Special relativity (time dilation due to velocity) on the other hand,...


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What you're asking here is how to take into account waste variables such as gravity loss, aero-forces, and ISP loss at sea level. These all depend on your rocket's specific flight profile. For example, rockets with high thrust to weight ratios will experience less loss due to gravity, but much greater loss due to air resistance. Your thrust to weight ratio ...


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A quick way to remember this is thrust is force. Assuming that the thermal blackbody radiation is isotropic it averages to zero so we can ignore that. Then for a spacecraft emitting EM radiation in one direction we can say that the thrust is just: $$T_{EM} = \frac{dp}{dt}$$ where $dp/dt$ is the amount of momentum per unit time produced in one direction as ...


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The rocket equation is meant to work with constant specific impulse. If you want to stay with the Rocket Equation, you can 'split' any stage into more 'virtual' stages (where the initial mass of the next stage is equal arbitrarily chosen dry mass of the previous one), find what delta-V you need to reach roughly 10km altitude and generate a 'virtual' stage ...


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If your propulsion system has a better specific impulse, then you can travel farther from your initial orbit. So as CubeSat/smallsat propulsion systems improve their efficiency, the range of orbits that can be reached while being launched as a secondary payload will be increased. Theoretically, a solar sail has infinite specific impulse and therefore could ...


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Could humans use it? Unlikely, but maybe. At high accelerations, what ends up killing people is the difference in density between cavities like your lungs and the rest of your body. People have theorized that with liquid breathing, humans could survive continuous accelerations of up to 1000G.


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If you use 100 times the electric power for 1/100 of time periodically, you win nothing. You get 100 times the thrust for 1/100 of time, mean thrust per time does not change. You can't fool energy conservation, each try is in vain.


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Yes, most GNC systems will correct multiple axes at once. GNC systems can get quite complex. Typically, each letter is its own piece of software. The Guidance determines where the spacecraft should be pointing at a given time or mission phase: it outputs a desired attitude (MRP, quaternion, etc). Navigation will determine where the spacecraft is currently ...


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