Questions tagged [natural-satellites]
Questions on celestial bodies that orbit planets.
23
questions with no upvoted or accepted answers
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Are there any bodies in the solar system whose rotation is almost tidally locked or barely tidally locked?
The Moon's rotation is firmly tidally locked to the Earth and the Earth's rotation is firmly tidally unlocked with respect to the Moon. I gather that Mercury's rotation is tidally locked in a 3:2 ...
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Help identifying a very slow-moving object during meteor shower photography
I just wonder if anyone could shed any light on this puzzle.
Two nights ago whilst I was out photographing the Lyrids meteor shower from the UK something else showed up on my images when I checked ...
4
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Is it possible to have a positive rational number of months (more than 1) in a year?
It is possible for a planet to have orbital resonance with a sun (e.g. Mercury has a 3:2 spin resonance with the sun). It is also possible for a moon to have orbital resonance with a planet (e.g. our ...
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How to distinguish primary hosts (stars) and orbiting satellites (planets) and tertiary bodies (moons) by their mass and trajectory?
Suppose one has run a gravitational simulation of N bodies (has the mass, vector positions, vector velocities, etc for each body), but knows nothing a priori about ...
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Which moons do have neutrospheres?
Or in other words: which moons do have ionospheres but not surface-bound ones? The space beneath an ionosphere is called a neutrosphere. I only know of Titan. I know that the Galilean moons and Triton ...
- 1,052
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Would magnetic reversals on Ganymede affect radiation levels at the surface?
Currently the intrinsic magnetic field of Ganymede is anti-aligned with respect to the Jovian magnetic field. If this situation changed to become aligned, either due to magnetic reversals of the ...
user24157
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What's the first written record of the moon being tidally locked to the earth?
I couldn't find references as to who first noticed (wrote down) that the moon was tidally locked to the Earth. This, to me, doesn't seem obvious from first glance, and looks like something only found ...
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What moons have cleared their orbits?
The Wikipedia article Clearing the Neighborhood lists three numeric parameters that can be calculated for bodies orbiting the Sun as a way to indicate orbital dominance: Stern and Levinson's $\Lambda$,...
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If Ganymede had a thick, Earth-like atmosphere, would the surface be protected from Jupiter's intense radiation?
Obviously, this is a totally hypothetical, alternate version of Ganymede, since it would also need to have more mass and a stronger intrinsic magnetic field to hold onto a substantial atmosphere. But ...
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Besides Luna, are there any models of how moons become spherical and round?
Question
Given the theorized exceptional formation of Luna, (Giant-impact Hyphothesis, Wikipedia), are there any similar animated models of how the other, much smaller, moons in our solar system ...
- 163
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Are there any moons of minor planets that orbit at high inclination to the plane of rotation of the parent body?
It occurred to me that one of the ringed asteroids or minor planets may answer this question about the alignment of planetary rings. However, it appears that the rings of Chariklo, Haumea and Chiron (...
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How many moons do we know are shepherds?
Shepherd moons are natural satellites near the edge of a planetary ring that have an influence on the shape and size of the ring due to their gravity. So it is possible for a satellite to be near the ...
- 17.2k
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Keplerian Elements for the Moon and Earth around their Barycenter
So I'm looking to replicate the inner Solar System to a decent degree of accuracy. So far I've been utilizing the Keplerian Elements and Equations for the planets, as shown here. There is one issue ...
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Why was the diaeresis removed from Pasiphae?
The Gazetteer of Planetary Nomenclature notes that the spelling of Jupiter's moon Pasiphae was changed from Pasiphaë in July 2009, i.e. they removed the diaeresis. I've been unable to track down the ...
user24157
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Speed of Moonrise relative to fixed point on ground
Due to the curvature of the earth, and the way the moon interacts with the atmosphere (especially close to the horizon), is there a known function that describes the speed of the moon relative to its ...
- 121
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Moons of migrated giant planets: Icy, Rocky, or none at all?
My understanding is that gas and ice giants form outside the "snow line" of their protoplanetary disk, then sometimes through gravitational interactions they are able to migrate into the inner star ...
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What is the brightness and size of Jupiter from the Galilean moons, the closest moon, and the farthest moon?
From the Moon, Earth would appear 4 times larger than the Moon seen from Earth, and the magnitude of a "full earth" is around -17.
However, Jupiter from the Galilean moons appear much larger ...
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Why does Titan's (relatively) rapid migration away from Saturn cause the planet to wobble faster, and eventually (maybe) tip onto its side?
Over the past year and a half, multiple articles in the popular press have come out talking about how unexpectedly rapidly Titan is moving away from Saturn, and how this is causing Saturn to wobble ...
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How to determine how often a planet's center will be collinear with its moon's?
Expanding on the question: Let's say I have a planet orbiting some star (earth-like, sun-like, for the sake of example). If this planet has two moons, M1 with orbital period of 30 earth-days and M2 ...
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Can we see traces of exo-moon formation?
Our Moon was likely formed by the collision of a Mars-size object with the Earth soon after the planets first formed. Would traces of such an event be detectable by observing the protoplanetary disc ...
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How do I calculate the hour angle of a planet's moon from a point on that planet's surface?
I'm worldbuilding and I'm trying to construct a standing stone calendar that'll accurately denote where to look for my planet's moon at its four major phases from 53.8 degrees South. So, I need the h0,...
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Angles in Moon, Earth and Sun system
Consider the vector positions of the center of mass of Moon, Sun and Earth, $\vec{r}_{\rm M}$, $\vec{r}_{\rm S}$, $\vec{r}_{\rm E}$, respectively, in a given reference frame.
Consider:
the angle ...
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Could a moon of a mini-neptune around a red dwarf harbour life?
I am planning a game where on could control evolution on an alien world.
I was thinking red dwarf as per here Habitable Planet around Red Dwarf
To my understanding three questions arise:
Tidal lock
...
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