Questions tagged [orbital-mechanics]
For questions dealing with how bodies interact with each other in space via gravitation.
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Plausible orbit to have a visible object slowly circle over the night sky
I want to have the inhabitants of a particular world - doesn't have to be a planet, can be a moon - be able to see a certain point of light - can be a planet, moon, star, whatever - moving in the sky ...
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How would you slow the speed of a rogue solar system? [duplicate]
I previously asked about a rogue solar system, ejected from the Milky Way and set on a course for Andromeda. After millions of years, arrival is imminent - now, the inhabitants who had been in ...
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Would this gas giant moon system be stable in the long term?
My narrative project takes place in a system of moons orbiting a superjovian gas giant, and lately I have been questioning wether it would remain stable in the long term, I know it is very nitpicky ...
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What is the highest apogee of a satellite in Earth orbit?
An Alien craft is approaching Earth and has detected satellites in Earth orbit (and many other strange phenomenon). Although the satellites have been detected, for various out of scope reasons they ...
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How would Earth's plants change in this speculated Earth-like planet?
In a revival of one of my older questions, A Habitable Zone Within a Habitable Zone, this Earthlike planet orbits a binary of yellow suns, which by itself orbits a binary of red giants. (Lifespan is ...
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Viability of a Planet Orbiting a K-type Star (S type orbit) with a White Dwarf Companion
Viability of a Planet Orbiting a K-type Star with a White Dwarf Companion
I'm working on a world-building scenario and am curious about the viability and specifics of the following setup:
Binary ...
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Long-term stability for a terrestrial planet with rings and a large sub-synchronous moon
Terrestrial earth-like planet with rings and moon (to scale, this was found in SpaceEngine and I love how it looks).
Rough Luna vs my moon apparent angular size comparison (Luna = 0.52°, my moon = ~4°...
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Day-to-Night observable Sky on a Orbital (non-Niven, small ring) [closed]
I'm assuming a lot of things here, but trying to visualize some characteristics regardless. What would the skyline look like? Day/night, seasonally, etc.
I'm imagining a structure that is a ring, but ...
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What color would the sky be in a multi-star system?
In this scenario, an Earthlike planet is situated in a quaternary solar system clumped into two binaries--a Parent, in which the planet orbits, and a Grandparent, in which the Parent binary orbits.
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Artificial Satellites Orbit Around a Cube with Uniform Surface Gravity
A cube-world with uniform surface gravity has been made using extremely strong materials of varying densities, and is orbiting a star, rotating on a axis between two corners (like spinning a d6). Due ...
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How would a cube-moon orbit a Cube-World with uniform surface gravity?
A cube-world with uniform surface gravity has been made using extremely strong materials of varying densities, and is orbiting a star, rotating on a axis between two corners (like spinning a d6). Due ...
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I may have made an error in calculating my spin-orbit resonance
I have a very warm planet named Phoenix I'm worldbuilding that's 1.2 times the mass of Earth, with a density somewhat smaller at 5.2 g/cm^3, orbiting at a distance of 0.1 AU from it's star in 10.2 ...
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On a planet with 6 moons, how often would all 6 be full at the same time? [closed]
The cycles/orbital periods of the moons are 12, 20, 20, 24, 32, and 38 days. How often/after how many days would all 6 be full at once?
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Would it be possible for a somewhat distant bianary star system to have a planet orbiting their barycenter within both their orbits?
There are 2 stars in a binary system, 268 AU apart from each other. Both are about 1 solar mass.
Would it be possible for some planet to be orbiting their barycenter (the center mass of both starts),...
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Space Cold/hot War with periodical cycles
It's the far away year 2000 and the Soviets and the Allies are locked in war, while on Earth side things are your constant bloodbath their assets in space are stationed in orbits that keep them far ...
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Lagrange Points regarding a moon 1.5 times the mass of Earth's Moon and one 0.75 times the mass of Earth's Moon
Working on a lunar orbit system. As place holder numbers, two moons are orbiting a planet equal to earth's mass. One moon, Selenara, is 1.5 times the mass of Earth's moon, and the other, Thoth, is .75 ...
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At what rate does my planet become tidally locked?
I am designing an alien planet for a speculative evolution project. It is slightly less massive than Earth and is orbiting around a red dwarf, within the Goldilocks zone. It takes 220 Earth days to ...
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Binary planets and dual moon alignment occurring once every 200 years
I am trying to figure out a 200 year cycle where Binary planets share 1 moon Planet 1 has its own moon that maintains orbit around it. The cycle would be as illustrated below. Moon 1 would belong to ...
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How would be a Lunisolar Calendar with 2 Moons?
The world I'm building it's a Super-Earth named Tempus, and it has 2 moons in an orbital resonance. One of the moons, named Tidra Moon, is closest to the planet and basically has the same influence on ...
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How much mass could be added around the Earth before the Earth's orbit around the sun changed?
In the not too distant future Earth will enter its golden age of industrialization and construction. Pulling raw materials from other planets (not from Earth), humans begin building mega structures ...
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Climate on a tidally Locked Moon
Im working on a world building Project that is based on a moon surrounding a gas giant. The moon in question is referred to in the simulation as "Melorn" and marked in yellow.
There are ...
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How do Hill spheres work for binary planets?
A small moon is able to maintain a stable orbit around a planet at just under half the radius of the planet's Hill sphere. Most of Jupiter's moons are in this configuration, possibly made more stable ...
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I have a world with two moons, and I was wondering how often they would both be full at the same time
As I said in the title, I have a world with two moons. One has an orbital period of 17 days Earth days (Moon 1) while the other has an orbital period of 57 Earth days (Moon 2) and the planet they are ...
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What are some things to keep in mind while designing a binary planet system with a sun-like star? [closed]
My planets are both the same size as Earth, with about the same water:land ratio. They are tidally locked to each other, but not the star. I don’t know much about planets and orbits and other things ...
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How is this possible: a moon with A) large apparent size B) that spins C) spins in a 5:1 spin-orbit resonance?
I wanted to give my planet a moon that spins every SIX days and waxes-wanes every THIRTY days.
The bad news: Luna always shows the same face to Terra because of something called tidal locking ...
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What are the orbital perturbations needed to destabilize a system to the point of taking some bodies out of resonance and kicking out another?
I have a gas giant with a mass of $1.63314\times10^{27}kg$ and a radius of 66,559.052km and orbiting it are 4 moons.
It orbits a star with 0.86M☉ at a distance of 5.03AU
My question is what ...
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Can you have a moon that rotates 21 times per orbit?
I want to avoid having my earthlike moon of a gas giant be tidally locked. Now I know that 3:2 or even 5:2 resonance is possible, but what about 21:1 for my moon? Is that too many rotations per orbit ...
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How far apart ought my type-S binary stars be if each is to host a stable planetary system?
Consider a G-class star (0.9457 Msol) as the primary and a M-class dwarf star (0.4335 Msol) as the secondary. If I want a stable planetary system around each (particularly the G-class), then how many ...
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How to build a world with magnetic levitation?
Picture this:
Alpha Centauri Cb (AC) has
14% Earth's oxygen
110% Earth's gravity
A 60-hour day/night cycle
240-hour orbit (10 Earth days = 1 AC year)
Eccentricity produces all 4 seasons in 4 days
...
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Is this a plausible way for an Earth-like exomoon to have earth-like seasons?
Imagine an earth-type world orbiting a Jupiter-like gas giant roughly within the habitable zone. If the plane on which the moon orbits the planet is tilted at an angle relative to the Solar System's ...
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Is that an elliptical orbit gas giant?
Let's say there was a ship that went into orbit around a gas giant roughly the size of Jupiter. It's going to have a highly elliptical orbit so it's much closer to the sun during summer than in winter ...
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Could one moon appear to always follow/lead another in the sky?
Is there any way a second moon would appear to hang out near the closer one in the sky? For example always appearing either ahead of or behind throughout the year, or even alternating between those ...
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Can this Star system exist?
Can this star system with this configuration plausibly exist or not? If not please explain why it can't exist or explain its issues.
Planetary system
Star A
1.1 M⊙
Planets
types
mass
semi-major axis
...
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Is there a way to increase the orbital period of a tidally locked moon without changing the distance to its parent?
The internet tells me that the orbital period of a planet is calculated via Kepler's third law which, to my understanding, says Orbital period = semi-major axis3
I have a gas giant (radius of 1 ...
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Implications of Venus and Mars having the same mass as Earth
Could anyone advise if there have been any simulations on the long term stability of our solar system if Venus and Mars both had the same mass as Earth ?
If not, is this something that can be answered ...
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How might seasons work on Alpha Centauri Cb?
(first post from a writer drafting a sci-fi novel, so please forgive any ignorance or missteps and TIA!)
Let's say Alpha Centauri Cb is habitable, under these conditions:
Air quality capable of ...
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What is the largest apparent size a moon of a habitable planet can have? [duplicate]
Inspired by this question: How large can an apparent size of a moon be?
I am looking for a moon that is:
a terrestrial moon with properties vaguely similar to Luna (not a binary planet, but it can be ...
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Is it possible to have stable system where the moon of earth-like planet is only visible part of the year from a fixed point on a surface?
Is it possible to have a stable system wherein the moon of an Earth-like planet is visible only during certain parts of the year (seasons) from a fixed point on the surface, mimicking the way some ...
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Could Moon Phases work in a Concave Hollow-Earth?
I'm trying to wrap my head around how phases of the moon(s) would operate in a hollow earth. For reference, I am picturing a situation like this:
In this system, the center of the hollow earth has a ...
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What considerations would have to be made for a spacecraft with minimal-to-no digital computers on board?
I'm writing a sci-fi book where the main method of travel involves collapsing a star into a black hole by putting a satellite equipped with some sort of handwaving mechanism into orbit around the star....
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What would it take for a spacecraft to travel to the sun's nadir and stop?
In a science fiction future universe, spacecraft routinely travel from a distance "above" a star's north or south pole to rendezvous with planets orbiting in the star system's orbital plane. ...
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Very large orbit binary/trinary star systems
In my universe, Ancient Aliens once visited Earth with consequences.1 At that time they left instructions2 that 5,000 years3 in the future something would happen.4 The instructions left behind a ...
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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?
I would like to create a world that is at a roughly medieval level of scientific understanding and which - as far as it appears to the inhabitants of that world - has a highly erratic day and night ...
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Could a planet realistically share an orbit with Jupiter?
So I've been working on a project where I modify the Solar System, and I originally had a small gas planet(like 5-10 earth massses) named Juno orbiting between Jupiter and Saturn. However, as it turns ...
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Question about finding an exact lunar orbit
I am trying to find a precise orbit for a moon that would allow it to always be in an eclipse. So, basically, I need help finding a formula for the semi-major axis and mass ratio that would get the ...
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Feasibility of a moon-planet orbiting an F star [closed]
I'm building an earth-type planet with typically human-like people, but a few differences. The human's particular area won't have much in the way of seasons being a large equatorial island. I'm ...
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How do I change earth's orbit so it is tidally locked to the sun? [closed]
In my world, I need to change the earth's orbit so it is tidally locked to the sun. How can I do this? No matter how unrealistic the solution—whether it be magic or what not—anything that can explain ...
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Partially tidally locked planed due to elliptical orbit... Possible?
Would it be possible for a planet with an elliptical orbit to be tidally locked to a star, only for a certain part of it's orbit?
If this is possible, then:
could the tidally locked side vary from ...
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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 ...
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Zero energy transfer between Earth and Moon with space elevators
I'm asking this out of curiosity, mostly as a response to Space elevator from Earth to Moon with multiple temporary anchors and some of the comments and answers there.
Suppose you're able to build ...
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