Questions on celestial bodies that orbit planets.

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2
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2answers
100 views

Could this three moons system be stable?

In my fictional world I have selected all parameters to maximize the Hills Sphere of my planet. The planet has three times Earth's mass and it is located in 2 AU from its star that's 1.4 times more ...
1
vote
1answer
90 views

If Venus had moon before and it fell back to Venus, why don't I see a unique, very big crater?

Does lack of a very big crater support the idea that Venus never had big moons before? If not, why can't I find a very big crater from the moon impact?
8
votes
1answer
161 views

Is it possible that Mercury was originally the moon of Venus after a giant impact?

Mercury looks like the Moon, and so it makes me think about a question: is it possible that Venus and Mercury were the a same planet originally, and a giant impact with that planet made it split into ...
3
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1answer
164 views
24
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2answers
6k views

Why does Jupiter have so many moons?

Jupiter has a great many moons - in the hundreds, and they're still being discovered. What is the current theory for where all these moons came from? Are they rocks flying through space captured by ...
1
vote
1answer
73 views

What effect does a natural satellite have on a planet's rotation and revolution?

how is the rotation and revolution of a planet that does not have a natural satellite different from a planet that has say 1 natural satellite (ex. earth and moon system).
3
votes
3answers
100 views

Are moons geologically active?

Are there natural satellites in the Solar System that are geologically active? This includes volcanism, existence and motion of tectonic plates, et cetera. Is it a common or a rather rare feature ...
4
votes
1answer
111 views

Why does Saturn have both moons and rings?

From my understanding, a ring can form around a planet when a moon gets too close to its Roche limit, and gets ripped appart by the planet's gravity pull. That makes sense to me, but I don't ...
2
votes
2answers
177 views

Can we have a second moon?

This question sounds like silly and rather fantasy filled. But can our earth's gravity capture a sizable asteroid and make it rotate around our earth like our moon which become visible from ground. Is ...
5
votes
1answer
240 views

Can a gas moon exist?

Could a gaseous moon exist in the same way as a giant gas planet? All the moons in the solar system are rocky, or icy. Why shouldn't gas planets have gas moons?
6
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4answers
587 views

Moon's orbit around the Sun

The Earth revolves around the Sun and the Moon revolves around the Earth. Out of curiosity I started thinking about the orbit of the Moon around the Sun and expected (assumed) it to be as follows: ...
4
votes
1answer
211 views

How is it that all planets (and moons) in our solar system are in equilibrium orbits?

Previously, I was told that in order for any bodies to orbit each other for over a long period of time, the orbital period, distance and masses have to be precisely matched such that the bodies won't ...
15
votes
3answers
537 views

Will Saturn's rings become a moon?

Planets form from disks of matter orbiting around a star; some moons form from disks of matter orbiting planets. If this were going to happen around Saturn, approximately how much time would it take?
2
votes
1answer
240 views

The dark side of the moon [duplicate]

I encountered this statement that the dark side of the moon is hidden from our sights. Could someone please explain?
1
vote
1answer
62 views

How is the heat production inside moons compliant with Conservation of Energy?

A Nova episode said that during stages of some moons' elliptical orbits, the moon is stretched, and friction causes the inside of the moon to heat up. I do not understand how this is compliant with ...
11
votes
3answers
3k views

Jupiter FM - What are practical and inexpensive ways for the amateur detection of signals from Jupiter, especially of the transit of her moons?

What modifications to a standard AM/FM or shortwave radio are needed in order to be able to detect radio-wave signals emitted from Jupiter? Would it be possible to detect the transit of the major ...
4
votes
1answer
51 views

Do celestial bodies have many asteroids orbiting them?

Are there statistics on the expected number of asteroids (of various sizes) to orbit planets and moons in our (or other) solar systems? Do we know of other natural bodies orbiting the Earth (besides ...
1
vote
0answers
17 views

How can exoplanet moons be detected? [duplicate]

How can exoplanet moons be detected? Are there current methods to differentiate exoplanets with moons and exoplanets without moons? Or, are only the combined masses of the exoplanet and its moons ...
6
votes
2answers
167 views

Official Definition of Satellite?

So I had an argument with a friend, which was about whether the Moon is a planet or a satellite. IAU 2006 Resolution B5 gives definitions on what it is to be a planet, but there is a vagueness, as I ...
4
votes
2answers
81 views

Is there a mechanism that makes small moons more rounded than comets?

67P/Churyumov–Gerasimenko has a highly irregular dumbbell shape. But the sample of comet shapes observed is very small, so I wonder if irregular shape is the norm for comets and for small moons. Many ...
5
votes
1answer
177 views

Wouldn't the rings of Saturn experience tidal effect?

The "Lord of the Rings" has more than 60 moons, some of which are larger than Mercury. My question is, wouldn't the ring, which is mostly comprised of rocks, experience tidal effect whenever a moon is ...
6
votes
2answers
330 views

Why does the Solar System have no (natural) satellites of satellites?

What are the conditions for a planetary moon to have a satellite of its own? How far do the Solar System's bodies fall from the necessary threshold?
7
votes
5answers
620 views

The Existence of Natural Satellites in Geostationary Orbits

While browsing through Physics SE, I noticed a question about satellites in geostationary orbit (unrelated to the one I'm asking here), and for a moment I interpreted it as referring to natural ...
5
votes
1answer
208 views

Theoretical limits for natural satellites having natural satellites

Is there an inherent instability or limit that prevents natural satellites like the moons of Jupiter from having their own natural satellites? I looked at other questions such as do moons have moons ...
5
votes
2answers
196 views

Can a gas giant have an other gas planet as satellite?

Is it possible for a gas giant (A very big one) to have an other smaller gas planet as satellite?
3
votes
1answer
186 views

Why natural satellites (moons) of all Planets are Solid?

Why the natural satelittes (moons)of all planets including moons of Gas Giants are are Solid or Rocky and not gaseous like them?
7
votes
3answers
565 views

Can you explain the pattern of Hill sphere sizes of the objects of the Solar system?

I found this image on calculations of Hill sphere for planets/dwarf planets of the Solar system. From http://en.wikipedia.org/wiki/File:Hill_sphere_of_the_planets.png I found it interesting that ...
3
votes
1answer
209 views

Could a habitable satellite of a gas giant have a stable subsatellite?

I have set a science fiction story on a moon, orbiting a gas giant (which orbits its star at approximately the same orbit as the Earth around the Sun), and given this moon its own satellites. The ...
16
votes
2answers
796 views

Do moons have moons?

Have we discovered any natural satellites of natural satellites of planets or dwarf planets? Even very small, or relatively short-lived - e.g. ringlets around Saturn's moons, some meteorites orbiting ...
3
votes
1answer
85 views

Movement of the satellites of the planets . . .

Is the movement of the satellites (moons) of a planet coplanar, like the planets being coplanar around the local Sun?
6
votes
1answer
60 views

Is there a pattern between the mass of a body and the mass of orbiting objects around it?

I was looking at Wikipedia's Solar system page, and it says that Sun represents 99.86% of the whole solar system mass. I found that pretty huge. So i calculated ratio of masses : Earth / (Earth + ...
5
votes
1answer
55 views

Could a cryo-volcano be the reason behind this colour difference in Iapetus's hemispheres?

Iapetus's hemisphere facing Saturn is dark, whereas the opposite one is bright. Could a cryo-volcano be the reason behind this colour difference in Iapetus's hemispheres?