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20

In theory if the two moons were in the exact same orbit on opposite sides of the planet then yes. Having the moons closer to the planet and smaller also makes that easier. For example geostationary satellites over opposite sides of earth will never have direct line of sight to each other. In practice though that would be a very unstable arrangement (even if ...


7

Yes, this is possible. A large moon and a smaller moon can share the same orbit if one is 60 degrees ahead of the other. In such an orbit, the smaller moon would be at one of the stable Lagrangian points L4 and L5. If the orbital radius is less than $\frac{1}{\cos (30^{\circ})} = \frac{2}{\sqrt{3}}R_M \approx 1.15 R_M$ (where $R_M$ is the radius of the ...


7

They would cook. You are asking for 0.3 atmospheres of water vapor. The temperature of water with that equilibrium vapor pressure is nearly 70 degrees Celsius, or 158 Fahrenheit. An unprotected human will not survive that for very long. And the fact that the air is already saturated with water means our natural heat rejection mechanisms won't work. The ...


5

Providing a comprehensive answer to "how do you build a base on mars" is a bit beyond the scope of a simple answer here, so I'll focus on the core of your question: what can you use to make an airtight chamber on mars? Turns out that bit, at least, is pretty easy: marscrete! You need to obtain sulphur (which mars seems to have reasonable amounts of), heat ...


4

The rooms are built in vacuum, and then filled with atmosphere, after a leak test. The mechanical engineering of keeping vacuum and atmosphere separate is well developed today. Many of our manufacturing processes require high vacuum conditions to ultra-high vacuum conditions similar to the moon. Assuming your building materials are being fabricated on ...


4

Laser Syntered Regolith First the dust and rock on the surface of the Moon would need to be passed through sieves, to enable the grade of material suitable for printing to be fed to the printer head. The process itself would be very much done as a 3D printer does it now, but being heated by lasers instead of a small scale heater element: building up ...


3

The force of gravity on a spherical body like a planet or moon is governed by Newton's laws. If a moon had the same surface gravity as Earth: \begin{equation} F_{gravity} = \frac{G*M_{earth}*m_{object}}{r_{earth}^2} = \frac{G*M_{moon}*m_{object}}{r_{moon}^2} \end{equation} Solving for the relative density of the moon and subbing in the info for Earth and ...


3

Our asteroid belt is so thin that we send spacecraft through it withiut fear of a collision. It won't overshadow anything. An orbital arrangement where a planet is eclipsed for a quarter of its orbit is very unlikely. I can think of two situations in which it can work: If your planet is orbiting a relatively dark body, such as a black hole or a pulsar, and ...


2

Trying to size the planet and the moon in a way that the transition through the planet's shadow takes around 6 months appears difficult. When placing the moon very close, it will orbit fast and pass the shadow quickly. When placing the moon very far out, the orbit is not realistically very stable, but its orbital velocity is slow so the shadow transition ...


2

The way I would do it is have your moon orbiting a gas giant which itself is in a P-type orbit in a binary star system. Your gas giant orbits a small, dim star which is a binary companion with a much larger, much brighter star. The primary energy source for your moon is the more distant of the two. The shadow period would occur when the bright companion is ...


1

From this link we know that Tidal force is defined like so: In celestial mechanics, the expression tidal force can refer to a situation in which a body or material (for example, tidal water) is mainly under the gravitational influence of a second body (for example, the Earth), but is also perturbed by the gravitational effects of a third body (for example,...


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The easiest propellant to make on the moon would be ALICE, or an aluminum nano-power mixed with ice. No need to separate out the oxygen and hydrogen from the water. ALICE Rocket Fuel Tests Another option is to use pure water heated with a nuclear reactor, making a steam rocket. This does not have the specific impulse of hydrogen/oxygen, meaning that it ...


1

So a potentially habitable exomoon of a giant exoplanet might be protected from the radiation zone by not orbiting with the radiation zone, which the giant exoplanet might not have, depending on various factors, and if the giant exoplanet does have a dangerous radiation zone that zone might not cover all the region where a habitable exommoon should orbit its ...


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