New answers tagged planets
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Is it possible for a planetary ring to exist beyond a planet's Roche limit?
Yes, but it would be unstable beyond about an order of magnitude greater than the roche limit. The outer edge of Saturn's rings is 8.1 roche limits distant, for example.
The reason being is as soon as ...
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How much difference would Alpha Centauri A cause to the climate of a planet about Alpha Centauri B?
You've done most of the hard work already. The effective temperature of a planet is given by:
$T_{eff} = (aI)^\frac{1}{4}$
Where $a$ is a constant based on properties of the planet (Albedo, rotation ...
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(Fixed) Fictional calendar is 345 days with 28 hours per day and 14 hours day and night cycle--how old are 13 year olds vs Earth calendar?
In the spirit of teaching a person to fish...
Comparing two related values is most easily done by reducing everything to the largest common unit of measure. In your case, the largest common unit of ...
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Do seasons occur on a tidally-locked planet?
Another possibility to get seasons not mentioned so far is if the planet has a thick ring system, like Saturn. Depending on the position of the ring's plane, the ring system can screen the sunlight on ...
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Do seasons occur on a tidally-locked planet?
Imagine a twin star system, with suns that are almost merged, both putting tidal stresses upon each other, reducing the ability to uphold pressure in gravity annhilation, allowing much light to escape,...
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What astronomical situation could account for the PERCEPTION of a very erratic day / night cycle for a planetbound population with limited science?
My offer to you: The planet with two-and-a-half suns, with the best new years eve fireworks one could ever ask for!
It is nothing very spectacular, sadly, but it may be plausible up to a point.
What ...
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Accepted
What's the maximum mass for an Iron Planet to have a magnetosphere like Mercury's?
Earth is a planet with an iron core, along with other elements of course. It isn't really possible to get a planet that is pure iron, or pure anything else for that matter.
So, we then get to the ...
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Could Moon Phases work in a Concave Hollow-Earth?
This is profoundly silly, but I love your illustration so I am going to have a go at this.
As drawn, the ball with all the stars on is small compared to the void in the sphere. Either the sky would be ...
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5
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Accepted
Could Moon Phases work in a Concave Hollow-Earth?
If you look at a model of our Solar System, you will notice that we observe phases only for the bodies (Mercury, Venus and Moon) orbiting between the Sun and Earth, due to the relative positions they ...
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2
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Accepted
What would a rough estimate of the global climate of an earth be like if lit by a geosynchronous ring instead of a point source?
There are numerous immediate and obvious differences that I can think of, mostly describing plant life, weather, and geology. I have to admit that my imagination only extends to things that such a ...
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How would a planet's surface be younger than the planet itself?
In the case of Europa, but also Io, tidal forces from Jupiter's gravity cause internal heating, leading to increased volcanic and tectonic activity. For instance, Io is the most volcanically active ...
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How would a planet's surface be younger than the planet itself?
There's a difference between material age and appearance age
@L.Dutch is absolutely right about renewing the surface. (I upvoted his answer). In that case, the material age of the surface (e.g., how ...
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How would a planet's surface be younger than the planet itself?
In short, you need a process that keeps renewing the surface.
One of the reason is plate tectonics. For this very reason also Earth surface is younger than the planet itself, and finding very old ...
- 276k
1
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How Do I Keep the Population of an Ecumenopolis Reasonable?
Oxygen
It is not feasible for your planet to import oxygen. Nor is it feasible for them to artificially produce it. (Technologically or economically would both work.)
Consequently, though the planet ...
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