# Tag Info

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A lot of answers here effectively state "no, but ..." and what I read was correct. I'll give you another "no, but ..." solution: You can adapt various other parameters to make it appear as if a moon was only orbiting in the southern area. Give the plant an axial tilt of about 90°. This exists in the Solar System, specifically Uranus. Have the "moon" orbit ...

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This is possible if we use another planet, not a moon. (this could be the size of the moon, or appear to be a moon at a distance, but have the gravitational effects of a planet) Step one, take two planets and put them in a binary orbit. Step two, make the planets rotate at their angular velocity, so the inhabited planet is tidally locked to be in the same ...

2

A moon that orbits at the L1 Lagrange point of a tidally locked planet, in theory, could do the trick. the planet is tidally locked-- which means that there is now a distinct gradient of hot and cold that may create "poles" for the inhabitants. For civilizations that lives in the twilight zone, the night side would function as the "north" as it gets colder ...

1

Not in the way you are thinking for the reasons given. However, don't give up hope just yet. Apart from geosynchronous orbit above a fixed point on the equator, you could have is something at or orbiting a Lagrange point (L1 or L2). This wouldn't be over the South Pole as such (unless the axis of rotation points at or near the sun making the planet nearly ...

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This answer contains two answers, rolled into one. First the Moon, then the Earth. The Moon: The Moon - in short: Lots of green and black crystals, but because of the sun they look a bit bluer than they would on Earth. The Moon - in full: First of all, although I said that the surface "may resemble the darker basalt of the Moon's seas/maria", it won't ...

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This may not be the answer you wanted, but this might give you an idea. Suppose the Moon is in a polar orbit. Suppose it is also extremely eccentric, with a periapsis of, say, 100,000 km and an apoapsis of 1,000,000 km. It will appear very close from the south pole at its closest approach, and very small everywhere else. If it has the same size as our ...

7

Yes. The other answers are correct about barycenter orbits, but we can adjust that with density. The average density of Earth’s crust is 2.83 g/cm3. The element osmium is the densest material known that can exist under merely planetary gravity. That metal has a density of 22.61 g/cm3. It’s neighboring elements of iridium and platinum are similarly dense....

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The moon could be in an orbit with a period of exactly one day, so it is never seen from the other side of the planet. Then, something could happen, e.g. In the way the moon casts its shadow, that causes an equatorial point to be the coldest zone on the planet, much like conventional poles here. Note that the orbit doesn't need to be around the equator; it ...

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The Orbit Matters If Enceladus is parked opposite Luna, at a matching orbit, then these changes will happen at minimum : Tides will occur at the same timing (remember, both close and far sides of the Earth flex out) , and they will be stronger . The night sky will be brighter on average, and dark nights will be rare. Enceladus has a lighter density and ...

28

Not quite. Orbits are constrained to have a focus in the system's barycenter, so you cannot have the satellite orbit a planet favoring one hemisphere only. What you can do is alter the orbit so that the dwell time favors one hemisphere - you can have the moon stay 80% of the time over the Southern hemisphere and 20% of the time north of the Equator. It is ...

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No. A moon has to orbit the center of mass, and it has nothing to do with planet's axle of rotation. The Moon, for example, does not orbit around Earth's equator, but rather around Earth-Moon barycenter.

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No. There are different shapes of orbit, but they all go all the way around the planet. You could have a low orbit over the equator which cannot be seen from the pole, but not the other way around.

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Presuming you'd park Enceladus well away from Luna's orbit, you'd get either much stronger and more complex tides (if closer) or slightly increased and more complex tides (if beyond). However, I'm not sure you could park another large moon inside our existing Moon's orbit without disrupting the system with three-body effects, so you'd probably have to park ...

4

My initial guess would be that the Earth, like the Moon, would lose about 2779.84 km of its average diameter, and calculations indicate that it would then have 0.478 x its original volume. My initial guess is more like "this is really hard". In order to remove mass from a body, you need to deliver enough energy to a portion of it to allow it to achieve ...

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Of course it's "possible" -- proof case, rockets have been sent to the Moon for decades (first flyby was around 1959, as I recall, impact in 1959 or 1960, and those were launched with the same boosters that launched Mercury orbital missions). You don't even need a warhead; targeting capability of a late generation ICBM with a chunk of concrete replacing the ...

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I'd say that Tidal Recession is one of the LEAST of the effects moving the moons around. Mars sized is a very big moon, even for a super Earth. It would be big for a gas giant. None of our planets have moons anywhere close to that size. With only 1 mars-moon, the super earth would essentially be in a binary system. Adding more moons would likely be ...

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Tidal Recession is only one of a number of factors in play here, and as Zeiss Ikon pointed out, it's going to be considerably LESS of a factor in your system than it is in ours because your moons are smaller relative to the primary. If you REALLY want stability though, you want to have a look at orbital resonance. If you set your moons up such that they ...

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Tidal recession is produced by the tidal bulge in the primary due to the mass of the moon(s). Our moon is huge by comparison to the Earth, so even though it's also incredibly far out compared to other large moons (and the sizes and masses of their primaries), it produces a good sized tidal bulge in the Earth, which (because the Earth isn't tide-locked to ...

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A re-tanking depot on the Moon is not ideal. In fact it would suffer from a lot of problems. First it is necessary to land on the surface which requires considerable propellant both LOX and presumably methane or hydrogen. It is then necessary to launch back into orbit again which uses even more propellant. Another issue is the availability of hydrogen on ...

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The best place for spacecraft is in space. Anything designed for efficient and/or fast long distance travel would be optimised for its job, and that job is flying from orbit to orbit. Landing and taking off from a planet or moon is a completely different job, requiring different kinds of engine and load bearing structures and indeed a much more strictly ...

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Jupiter is known for having a strong magnetic field. Let's say that this planet has the same. Being so strong, it simply makes sense that no living species would adapt to use a non stable reference, such as the magnetic field resulting from the interaction of the moon with the planet, for migration patterns. Incidentally the magnetic field also disturbs ...

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