All Questions
24 questions
3
votes
2
answers
317
views
How do I figure out where a moon is in the sky at a given time and place?
I use this planetarium tool to see the position of the Moon to check I have it in the right place for a given place and time, for my non-Earth plant. I'm considering having another moon. How would I ...
- 1,889
18
votes
5
answers
7k
views
By what mechanism could a planet be locked into permanent solar eclipse?
I've got an image in my head of a world where it's just normal that the star is black with a golden halo around it - in other words, where the planet is in a state of perpetual solar eclipse.
Are ...
- 1
3
votes
1
answer
242
views
How stable would partial planetary rings be on Lagrange points?
Context
There's a comparison to what I'm talking about on a larger scale: Jupiter's got its Trojans and Greeks, and Earth does have them too. Those are more or less loose and sparse groups of ...
- 1,327
1
vote
2
answers
159
views
Reverse engineering the Hill Sphere?
I'm wondering if anyone has run into the issue of "I know the general idea of how big my moon is but not the parent planet" and how to sort of reverse engineer finding out the mass/radius of ...
- 66.3k
3
votes
3
answers
1k
views
Could a planet without an orbiting moon still be habitable to human life in at least one small pocket? [closed]
No moon likely means no tides. Does this make a planet half water, half land, or similar divisions? Do freshwater and saltwater have separation? Or would it just be a planet like ours, with delineated ...
- 66.3k
4
votes
4
answers
377
views
What are the odds of a binary solar eclipse?
I'm currently creating my own binary star system which includes a circumbinary planet that has two moons. For simplicity's sake, the stars, planet, and moons are comparable in size to our own Sun, ...
- 1,899
5
votes
5
answers
468
views
Is there a way for a permanent Lunar eclipse, or another Object to always be in Earth's shadow?
I have a question regarding worldbuilding and haven't found a question like this yet, so I created an account and hope that someone can answer it :D
As a starting point, imagine our real-life Sun, ...
4
votes
2
answers
1k
views
What is the minimum size of an habitable planet to have two moons?
For the sake of the question, let's define a moon as a natural satellite at least half the size of our Moon. It needs to be spherical like our Moon, not like Phobos and Deimos on Mars. The imaginary ...
- 31k
8
votes
4
answers
2k
views
Is there a plausible way to have a Gas Giant with two or more earth to mars sized moons orbiting it in the Habitable zone?
A hypothetical scenario I'm batting around in my head is a Habitable Gas Giant system consisting of a roughly Saturn sized body orbiting a sun like star at a comfy goldilocks zone distance. Orbiting ...
- 1,207
4
votes
2
answers
438
views
What would it look like for a planet with two moons and rings during a double eclipse?
Since we just had an eclipse, I began to think: what would it look like if a planet had rings and two moons?
Now, there are two solar eclipses going on at the same time! What would the sky look like?...
- 837
11
votes
2
answers
570
views
How long would this eclipse last?
For a moon orbiting a gas giant which is in turn orbiting a star, I want to know how long the eclipse would last for an observer standing on the moon when the planet passes between the moon and the ...
- 20.4k
3
votes
1
answer
425
views
How long can a moon remain non-spherical, and what might it look like when full?
I'm trying to "build" a world in which the moon is always visible at night, and only at night, to the majority of areas on that world. I've been told that an L2 Legrange point could be a viable ...
- 907
9
votes
1
answer
362
views
Feasibility and consequences: the cosmic dance of twins habitable moons
I am aware of being a newbie in the field I am asking my question... please be kind and explain what I did wrong if I make a mistake.
The idea from where the problem bloom
I love worldbuilding. ...
- 142k
41
votes
3
answers
13k
views
Habitable moon of a gas giant: working out the sizes and distances
I am attempting to create fictional, stable P-Type binary system, featuring a gas giant in a stable orbit, with a habitable Earth-like moon. “Is a Jupiter-sized planet plausible in a habitable zone?” ...
- 11k
15
votes
7
answers
2k
views
Could a moon have its own satellites visible from the planet it orbits?
Say you have a planet and the planet has a moon: could the moon have visible satellites as well? I don't mean a gas giant planet, I mean something habitable by humanoids or humans.
Will the moon's ...
- 69.8k
7
votes
1
answer
378
views
How would tidal forces impact two habitable moons in a horseshoe orbit?
I saw this video a while ago, and recently it's gotten me thinking. Towards the end of Artifexian's video on gas giants and habitable moons, he mentions the idea of having 2 habitable moons in a ...
- 2,952
4
votes
1
answer
326
views
That's a big planet, but how big is it?
If a tidal locked terrestrial sized moon with 0 eccentricity, 0 incline, and was orbiting .01 AU away from a gas giant with 12 Jupiter masses (which would have approximately the same radius as Jupiter)...
- 42.3k
3
votes
1
answer
104
views
Can an ocean moon with a mass of 0.5 earth masses stabilize the axial tilt of a planet two times bigger than earth?
The world will going to be the homeworld of an hairless feline humanoid race, but I want to see the plausibility of this scenario?
- 468
5
votes
1
answer
323
views
Could my moons-planet 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 ...
- 53
3
votes
1
answer
426
views
Fusing Mars and Ganymede
Would it be possible to move Ganymede into Mars' orbit causing them to fuse together like the two proto moons of earth?
The new planet "Marmede" would have a mass equal to 13.2 % of Earth.
How ...
- 102k
4
votes
1
answer
525
views
Binary planet eclipses
I know that on a binary planet you would have planetary eclipses (basically like a solar or lunar eclipse but with planets instead of moons).
If there also is a moon, things would be much more ...
- 5,797
7
votes
1
answer
1k
views
Apparent magnitude of my moon as seen from the planet's surface
Setting: we have a fantasy world which is a planet with much of the same conditions that can be seen on Earth, but with the difference that it is orbited by a moon with a mean diameter of 3 500 km. ...
- 28.8k
13
votes
5
answers
807
views
How would life on the satellite of a Super-Jupiter be? Is it even possible for such a satellite to be habitable?
Recently I had an idea for a world setting. A large part of this world focuses around a habitable satellite the size of Earth orbiting a Super-Jupiter. The fact that it's a moon is pretty integral to ...
- 97.9k
10
votes
5
answers
415
views
Eye in the Sky Effect
Is there any conceivable way that a planet with two moons--one being visibly red to the naked eye due to its mineral composition--could align in an eclipse in such a way so that the whole effect looks ...
- 211