Skip to main content

Questions tagged [natural-satellites]

Questions on celestial bodies that orbit planets.

Filter by
Sorted by
Tagged with
8 votes
2 answers
1k views

How long is a "lunar month" in Jupiter?

For Earth, the lunar month is well known. But Earth has only one moon. But on Jupiter, how long does it takes for the same moon configuration to appear in the "sky" of the planet? For the sake of ...
Mindwin Remember Monica's user avatar
8 votes
1 answer
1k 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 ...
javaPhobic's user avatar
8 votes
1 answer
376 views

Why is Uranus able to support a regular satellite system?

Uranus has an obliquity of 98° which means that the mutual inclination between a satellite orbiting in its equatorial plane and the orbit of Uranus around the Sun would exceed the critical angle for ...
user avatar
7 votes
4 answers
2k views

Could an orphan/rogue planet have a moon?

Is there some reason why an orphan or rogue planet wouldn't have a moon? Let's say it started out in a normal system and then just got flung out by an unstable orbit.
user avatar
7 votes
2 answers
791 views

When will the next series of mutual eclipses of Jupiter's moons begin?

When I was young (I won't tell you when) I saw one of the four Galilean moons of Jupiter suddenly disappear while watching through a small refractor. It wasn't a coincidence, I'd seen the prediction ...
uhoh's user avatar
  • 30.7k
7 votes
3 answers
2k 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 ...
Zoltán Schmidt's user avatar
7 votes
2 answers
490 views

Is there a timekeeping word for the orbit of a moon?

For a planet, we can colloquially refer to its period of rotation as a "day" and its period of revolution around its parent star as a "year." Some worlds have unique terms, such as Martian days being ...
Nerrolken's user avatar
  • 637
7 votes
2 answers
1k views

What colours can rocky planets (or moons) have

I am currently working on a simple program to randomly generate and display rocky exoplanets (for a space based strategy game), but I am having some problems figuring out what colour the rocks of ...
Nikolaj's user avatar
  • 231
7 votes
2 answers
878 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?
user avatar
7 votes
1 answer
441 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 ...
user6760's user avatar
  • 2,501
6 votes
1 answer
619 views

Are satellites of trans-Neptunian objects classified as trans-Neptunian objects?

I can't seem to get a consistent answer regarding the question of whether or not satellites (moons) of trans-Neptunian objects are considered to be trans-Neptunian objects, given that they do not ...
Mark Morales II's user avatar
6 votes
2 answers
871 views

Has any moon achieved "retrograde equatorial orbit"?

There are many moons which have low (almost negligible) inclination and can be considered to rotate at the planet's equatorial plane. For instance, Galilean moons have almost negligible inclination (&...
Nilay Ghosh's user avatar
  • 4,695
6 votes
2 answers
261 views

horseshoe orbits

I'm designing a moon system for a fictional setting, and recently came across the idea of horseshoe orbits. The gist of my question is how many objects can share a horseshoe orbital at a time? I ...
user49466's user avatar
  • 161
6 votes
1 answer
2k views

Can a gas moon exist? [duplicate]

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?
Sir Cumference's user avatar
6 votes
1 answer
102 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?
Matheo's user avatar
  • 163
6 votes
3 answers
2k views

Telescope buying guide for a beginner in India

I am located in the southern part of India and am looking forward to buy a telescope to gaze up to look ay farther planets, moons in our solar system and take pictures. How should I go about getting a ...
Ciasto piekarz's user avatar
6 votes
1 answer
168 views

Is there a reason Tethys and Dione are the only moons known to have trojans?

Trojans have been found at the L4 and L5 points of most planets. However Tethys and Dione, both moons of Saturn, are the only known moons in the Solar System to have trojans of their own. Is this just ...
user177107's user avatar
  • 2,699
6 votes
1 answer
383 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 ...
Erik's user avatar
  • 161
6 votes
1 answer
64 views

Does a more massive main proto-body result in more massive satellites? More satellites?

Suppose that we have a forming protostar and an accompanying protoplanetary disk. Does the mass of the protostar have any direct relation to the masses of resulting planets or amount of resulting ...
Max0815's user avatar
  • 1,872
5 votes
3 answers
2k views

Why doesn't the moon always follow the same path? Or why aren't the moon's apoapsis and periapsis fixed?

I have seen many times that the moon doesn't follow the same path. Sometimes the moon gets very close to earth which is shown in the news. If the periapsis of the moon is soo close then why doesn't a ...
Aarav Prasad's user avatar
5 votes
2 answers
2k views

Sum of the Masses of All Moons in the Solar System

I'm looking for the total mass of the moons in the solar system in Earth Mass this would be include the 67's moons of jupiter, the 62's of saturn, the 27's Uranus and the 14's for Neptune. it's a ...
Jeremy Talus's user avatar
5 votes
1 answer
140 views

What are these bumps on Europa?

The surface of Europa is famous for all the criss-cross lines thought to be cracks in the ice above a water ocean that somehow re-freeze. But in the photo below I also see a lot of raised "bumps&...
uhoh's user avatar
  • 30.7k
5 votes
3 answers
201 views

Why are there gaps in the size distribution of solar system moons?

Looking at the moons natural satellites in the solar system, the larger ones appear to fall in a few groups of sizes. Eyeballing the above picture, there appear to be a bunch of big moons (the ...
JanKanis's user avatar
  • 591
5 votes
2 answers
611 views

What variables are needed to calculate simple horseshoe orbit times?

EDIT This was NOT a duplicate of Horseshoe orbit cycle times. But that other question has been deleted, regardless. My original question asked for the answer to the equation(s), and provides many of ...
Harthag's user avatar
  • 379
5 votes
1 answer
606 views

Why are the natural satellites (moons) of all planets solid?

Why are the natural satelites (moons) of all planets - including the moons of the gas giants - solid or rocky, and not gaseous?
CrownedEagle's user avatar
5 votes
2 answers
230 views

How to calculate the frequency of a gas giant eclipsing the sun from a moon?

Say you have a moon around a gas giant which goes around a star. If the moon has an inclination of around 0° relative to the gas giant's orbit, the gas giant will eclipse the star every orbit of the ...
Astavie's user avatar
  • 71
5 votes
1 answer
589 views

Do all moons orbit their planets on the ecliptic?

Do all moons orbit their planets on the ecliptic? Do they all follow this same process as the moon that orbits Earth, or is their some random distribution with some even having extreme polar orbits.
chaonomy's user avatar
  • 1,119
5 votes
1 answer
194 views

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 ...
Roger Wood's user avatar
  • 1,379
5 votes
1 answer
215 views

How can a rotation period of a planet's satellite/moon be "chaotic" (like Hyperion around Saturn)?

According to wikipedia (see info below image) Hyperion's rotation period around Saturn is "chaotic". What does that mean? The period (in days/hours) is different every rotation without any law ...
caasdads's user avatar
  • 205
5 votes
2 answers
296 views

Say we were to bring Titan to Earth's orbit. How much would its atmospheric pressure change?

I've heard one of the reason why Titan has such a thick atmosphere is because of its really low temperature. So say that were were to magically bring Titan to the Same orbit as Earth, and the moon ...
Physicyquestionasker's user avatar
5 votes
2 answers
319 views

How would a small TCO (temporarily captured orbiter) or other natural Earth satellite most likely be detected?

A sentence from the abstract of The population of natural Earth satellites states: At any given time there should be at least one NES of 1-meter diameter orbiting the Earth. The average temporarily-...
uhoh's user avatar
  • 30.7k
5 votes
1 answer
164 views

How to cool down a moon?

I'm doing an Astronomy project and need to terraform a moon. It is about the size of Mars and orbits a gas giant which is at a distance of 1.28 AU of its star. I though about putting a sunshade at the ...
RafaelUL's user avatar
5 votes
2 answers
861 views

Up to 384 minor planets (including Pluto) qualify as planets?

In 2006, the International Astronomical Union redefined the definition of planet in order to exclude Pluto, Eris, and several other objects whose category was disputed. This new definition of a planet ...
Nirvana's user avatar
  • 251
5 votes
1 answer
145 views

How far from the Sun can an Earth TCO (temporarily captured orbiter) go after leaving?

Objects which are temporarily captured into an Earth-Moon system orbit (temporarily captured orbiters or TCOs) by definition will leave this orbit. While the term suggest an Earth orbit, it's really ...
MMP's user avatar
  • 51
5 votes
1 answer
210 views

What would theoretically be dissolved in the interior oceans of icy moons and planets?

I know we have some indication of "what's in the water" from the plumes of Enceladus, but would other places be the same. For instance, could the deep liquid water of Titan contain dissolved ...
Jack R. Woods's user avatar
5 votes
1 answer
272 views

Will Lunar Months be the same length Millions of Years in the Future?

If I remember correctly, the amount of time it takes for the moon to rotate around Earth is getting longer over time. Is this true, and if so or the opposite is true and a lunar month is getting ...
Dromeoraptor pennato's user avatar
4 votes
1 answer
361 views

Moons with curlicue paths around our Sun?

I naively believed that since our Moon orbits Earth, and since Earth orbits the Sun, the path our Moon might take around the Sun would be this type of epitrochoid curve: I was surprised and delighted ...
Connor Garcia's user avatar
  • 16.3k
4 votes
2 answers
211 views

Are there areas within Jupiter's magnetosphere without powerful radiation?

I know Jupiter has powerful radiation belts, but I'm wondering if there are places within the magnetosphere that are relatively calm. I'm asking about Jupiter (a gas giant we know) because I'm curious ...
Elhammo's user avatar
  • 1,107
4 votes
2 answers
1k views

What is the minimum mass of a celestial object so that it can have a moon?

I was wondering how massive something have to be so that it it can attract moons by pop culture standards (ellipsoid/round shape). Could a planetoid have a moon? What is the relation between the mass ...
inquisitor's user avatar
4 votes
1 answer
751 views

How many moons in the solar system have water?

I've heard of a few moons in the solar system that have water, like europa and enceladus. However, I can't find information about whether there are other moons as well. I'm guessing there are more, ...
Picachieu's user avatar
  • 216
4 votes
1 answer
583 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 ...
Tritium21's user avatar
  • 151
4 votes
1 answer
272 views

Could the Moon naturally capture a large asteroid and keep it as a subsatellite? For how long?

(Edited at James K's recommendation to stay on-topic for this SE.) From my reading on this SE and from Googling I've gotten conflicting reports on the viability of subsatellites this close to the Sun,...
Lielac's user avatar
  • 43
4 votes
2 answers
208 views

Is the satellite of a small star in a binary solar system a moon or a planet?

What exaclty distinguishes a moon from a planet? In a binary solar system that has a large star in the center and a smaller star - among some planets - orbiting that large star, and the smaller star ...
matthias_buehlmann's user avatar
4 votes
1 answer
392 views

What caused these strange craters on Hyperion?

I was looking at pictures of the moons of Saturn and noticed that the craters on Hyperion have a strange shape, somewhat resembling sinkholes. They look a lot deeper than the impact craters on other ...
usernumber's user avatar
  • 17.6k
4 votes
2 answers
159 views

Tallest cliffs, by falling duration

If you threw something over a certain cliff on a moon of Uranus, it would take over ten minutes to hit bottom. By this measure, local fall time rather than absolute height, what are the near ...
Camille Goudeseune's user avatar
4 votes
3 answers
610 views

So is there nothing like satellite anymore?

I just read this article. I don't know how credible it is, since I couldn't find any link to the original paper. But it says that pluto will be considered a planet again, along with more than 100 ...
another 'Homo sapien''s user avatar
4 votes
1 answer
281 views

How do a planet's moons and a planet's rings interact?

I am making a video game which features a planet and its moon. And I thought I would add rings too. But that got me wondering... how do a planet's moon and a planet's ring influence each other? Does ...
Bram's user avatar
  • 141
4 votes
2 answers
881 views

What is minimal aperture/magnification to recognize phases of Galilean moons?

Given you take a (non-amateur) refractor telescope, what are aperture and magnification required to recognize phases of the four Galilean moons? What did Galileo see: http://www.astro.umontreal.ca/~...
J. Doe's user avatar
  • 283
4 votes
2 answers
439 views

Is it possible for a planet to have multiple moons in a nearly stationary orbit?

I have done a lot of searching online and while I have been able to find out that theoretically a moon could exist in a near-synchronous/stationary orbit, I am wondering if it is possible for multiple ...
Ernesto's user avatar
  • 43
4 votes
2 answers
545 views

What is the difference between a moon and a random chunk in the rings

Jupiter has 79 (known) moons, Saturn 82, Uranus 27 and Neptune 14 (numbers come from Wikipedia). These planets also all have rings. The rings are made up of chunks of rock and ice. There also are ...
usernumber's user avatar
  • 17.6k