# Tag Info

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Here's a brief answer since some people are trying to close the question and prevent answers: As @ikrase points out answers to the Physics SE question Why is the Peltier / Seebeck Effect's efficiency so low in practical devices? are helpful here. Briefly, there are two main parts to an RTG's conversion efficiency Thermodynamics limit The fraction of the ...

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A problem with this analysis is that increasing the radial force preserves angular momentum, while two orbits of different radius do not have the same angular momentum. Your process does thus not end up with a lower circular orbit, but rather a hyperbolic orbit with low perihelion. These are different enough that claiming one is an approximation for the ...

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It is possible to generate electricity from Martian dust storms in the sense that you can get a non-zero amount of energy from it. However, the energy available, particularly from the method you specified, is very little and most definitely not enough to power a colony. On top of that, dust storms are by no means frequent enough to sustain any sort of ...

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Partial answer, waiting for a rocket scientist to chime in. This is a cool question! Celta-v calculated from exhaust velocity using the Tsiolkovsky rocket equation for each stage would be a huge overestimate because it doesn't account for things like atmospheric drag or gravity. So you'd have to numerically integrate over a specific trajectory for a final ...

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The relevant quantity to consider here is the specific orbital energy: The specific orbital energy $\epsilon$ (or vis-viva energy) of two orbiting bodies is the constant sum of their mutual potential energy ($\epsilon_p$) and their total kinetic energy ($\epsilon_k$), divided by the reduced mass. \begin{align} \epsilon &= \epsilon_k + \epsilon_p\\ &...

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Yes, it is possible. When everything is taken in to account, you can get a modest amount of wind power on Mars. The thicker atmosphere takes away some of the penalty, and the generally higher wind velocities. It could be an important backup power source for when there is no solar power available. It will follow the traditional wind power model, however, and ...

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Because you are making use of fuel (reaction mass), this can only work for a finite time, but it must be possible for a while. We could imagine that we have a "largish" ship so the energy we get from the source imparts a negligible momentum. Then we could use that energy to push off from the bulk of the ship to accelerate toward the energy source....

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Two scientists, Brooks L. Harrop and Dirk Schulze-Makuch, have hypothesized that a solar wind satellite built with the right proportions can generate an upwards of 1 billion billion gigawatts of energy(see pt. 5 below). The satellite's main components consist of a copper wire, receiver, and a sail. The satellite's charged copper wire, aimed at the sun, would ...

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Yes, that sort of orbit is possible. It is a closed transfer orbit. It is noted in the Wikipedia article about a Cycler, a potential ferry spacecraft using that sort of orbit, that would pass close to two celestial bodies at regular intervals.

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There should be little charge remaining on the rocket body during powered ascent, despite the significant charge generation. The reason being that the rocket body forms fraction of a percent of the very large conductive body that is passing up through the atmosphere. The vast majority of it is the conductive and neutrally charged plasma exhaust from the ...

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