Questions tagged [orbital-mechanics]
For questions dealing with how bodies interact with each other in space via gravitation.
393
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Can an Unstable Ternary Star System Last Several Hundred Years?
After reading the following question, I know that there are not that many solutions to the 3-body problem, and I know that a ternary system is unstable. The 3 stars all orbit each other in a rotating ...
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3answers
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Can planetary bodies have a second axis of rotation?
Is it possible for a planetary body to have a secondary axis of rotation? For example let's say there's an Earth-like body that is spinning with its North Pole facing the Sun. Imagine that the North ...
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1answer
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Stabilizing Synchronized Orbit
The planet in my story, Ser, is actually in reality a moon orbiting a larger body called planet Rea. Ser is located in the L1 Lagrangian point, which means it takes the same amount of time to orbit ...
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2answers
177 views
What are the size limits on an spin-gravity space station?
A spin-gravity space station, a ring-shaped structure that creates a faux gravity on the inside of the ring via inertia, has been depicted as no bigger than a house and as massive as a solar system.
...
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Gravity on an Orbital Ring
Added 9-15-19:
Thank you all for your comments. I will be reading them through carefully.
I have quickly skimmed through the answers and I do appreciate your corrections on terminology and ideas, and ...
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1answer
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A Stable Red Giant Trinary System
In an alternate universe, we have a spot in the Orion Arm where we have nine Earth-like planets orbiting three red giants. Judging from the size and luminosity of each star, it's been conferred that ...
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3answers
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Moons that can't see each other
Could 2 moons that orbit same terrestrial planet never see each other if they orbit the planet at same time?
Moons have different mass and gravity.
6
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2answers
254 views
Is there a website that will run orbital simulations because I don't have a PhD in math
I'm just trying to write a RPG adventure for a sci fi company. So when I have to figure out what kind of orbits, masses, major axis, etc are needed for the system I need to design and I see:
$T=2\pi$...
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2answers
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What could cause a planet to be in shadow for a 6 earth month period every couple of earth years?
My previous question ruled out having a moon orbiting a gas giant. I've got an interesting ecosystem (my bad, biome was the wrong word) that evolved based upon the idea that the world is eclipsed for ...
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2answers
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If Earth Were a Gas Giant's Moon
Here is what we know of Earth:
Mass: 5.972 sextillion metric tons
Diameter: 7,917.5 miles
Density: 5.51 grams per cubic centimeter
Rotation: 24 hours
Revolution: 365 days
Core: 760 miles wide, ...
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3answers
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In Search of a Super-Bright, Super-Stable Star
Long ago, I asked a question on how to make possible turning the nine realms of Norse mythology--Midgard, Asgard, Vanaheimr, Jotunheimr, Alfheimr, Hel, Nidavellir, Niflheim and Museplheim--into nine ...
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Could a planet have a naturally occuring moon at one of its Lagrange points?
Would it be possible for a planet to naturally have a moon or large natural satellite at one of its Lagrange points?
If so would it then also be able to have a second moon that would be orbiting this ...
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1answer
86 views
Could a single highly elliptic orbit be used to redirect to another planet?
I'm modeling this on the Voyager 2 flight path. I want to have this flight at this particular time, and not wait for a more advantageous launch window.
Based on this orbital configuration (1st ...
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1answer
104 views
How Far Can The Stars Ve and Vili Orbit The Main One, Odin?
In this solar system, there are three K-type main sequence stars, or "orange dwarves", named Odin, Vili and Ve. At the center of this solar system, Odin is 80% the mass of our sun. The middle star, ...
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5answers
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In order to successfully have 3 orbital rings around a planet how do you have to orient them?
I am writing a short story about an overworked planet whose civilization has achieved space elevators and orbital rings.
The planet, which is earth-sized, has three complete orbital rings in stable ...
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1answer
153 views
How many terrestrial moons can my planet hold?
I have a Gas Giant with 13x the mass of Jupiter. How many satellites of Earth size and mass can it hold safely in its orbit?
Edit: This gas giant lies smack dab in the middle of its parent star's (...
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3answers
271 views
Super earth habitability
I'm trying to build a super Earth that's capable of sustaining human life for space exploration in a way that's close to reality. So far I'm lacking some understanding of planetary science and human ...
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4answers
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Where should a runway for a spaceplane be located?
If a spaceplane like the Rockwell X-30 existed and was flying to a location in geostationary orbit, would it be substantially more efficient to take off from a runaway at the equator, or would it not ...
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0answers
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I'm inventing a new calendar. What are good criteria for the choices of first day, first year, and first hour? [closed]
I'm inventing a new calendar:
It will be used worldwide.
It uses an intercalary (366th) day to be inserted every 4 years.
If extremely successful (unlikely I know), it will replace the Gregorian ...
10
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1answer
193 views
Moons in Binary Orbit
Writing a werewolf story, and decided for a bit of flair, so I wanted two moons in orbit. Did a bit of digging, and I found out that to do that, I'd need to either have them in separate orbit (no ...
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5answers
163 views
Axis of rotation of a wheel space station [duplicate]
Is it possible for the axis of rotation of a rotating wheel space station in orbit to be aligned with the center of the Earth?
I'm wanting a situation where a person on the station could look out one ...
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4answers
182 views
Rotation period of a planet around a star (sun)
Is it possible for a planet to be much further away from its star than earth is from the sun (because for example the star is much brighter/Hotter) yet still have a comparable (as in not tens if not ...
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3answers
271 views
Which moon is most favourable as a refuelling station?
My hypothetical gas giant has five major moons. Three of those moons are icy bodies with abundant water ice and volatiles. Any of these could provide fuel for translunar spacecraft, or for spacecraft ...
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3answers
473 views
Can I render satellite deployment impossible, or at least impractical, by exploiting the Kessler syndrome?
I want to render impractical the deployment of satellites by exploiting the Kessler syndrome.
Why, you ask? Maybe I'm an evil overlord and I don't want those pesky satellites flying over my lair.
...
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1answer
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Could a rotating ring space station have a bolo-like extension?
If the outer ring of a rotating space station was producing the equivalent to 1G, but a higher G was needed could in small modules, could a bolo-like attachment be included with the ring to accomplish ...
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5answers
159 views
Is it possible to move planets to get them nearer to Earth? [closed]
Could we move rocky planets such as Mercury, Venus, and Mars to be closer to Earth's orbit?
I know it sounds like a silly question and it's impossible right now, but if there is a small possibility, ...
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1answer
321 views
Brown Dwarf Star vs Gas Giant as parent for habitable moon
I seek to build a habitable moon of a giant planet, thus I looked at the Rouche Limit Equation to figure out how to get the biggest possible Hill Sphere for my moon to exist in.
$r_H = a(1-e)\sqrt[3]{...
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1answer
133 views
Would life be possible on a planet that has an axis of rotation that always “pointed” directly at the sun? [duplicate]
Preface: I'll be calling call the orbit described in the question title a "solar-oriented orbit" for the sake of convenience, as "a planet that has an axis of rotation that always pointed directly at ...
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7answers
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If a planet has 3 moons, is it possible to have triple Full/New Moons at once?
In the story I created, the Kingdom of Oneirou has 3 Moons--Artemis, Rahu, and Zorya--all of which have their own independent lunar cycles.
However, it's officially stated as early as Chapter 2 or 3 ...
3
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3answers
96 views
Object in the orbit or orbiting Uranus's moon Puck
I realize the response to this question is fairly involved but here goes. I need to have an alien spacecraft either in orbit around Uranus's moon Puck or somewhere in Puck's orbit around the planet if ...
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5answers
242 views
Can multiple similar planets share the same orbit without interfering with each other too much?
Let's go with an example. Three planets, all of roughly earth's size, follow the same orbit around a star with a mass of roughly 1 sun. Basically, all three planets are almost identical to Earth, ...
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10answers
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Make solar eclipses exceedingly rare, but still have new moons
Given a system similar to the Earth/Moon/Sun system, how would one go about making solar eclipses rarer than they are here on earth, but keep new moons similar to how they currently are (or at least ...
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18answers
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How could a planet have erratic days?
I want to describe a world where one doesn't know how long the day will be. It can be anywhere between 18 and 30 Earth-hours. Would such days be possible in our reality?
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1answer
160 views
Meterology of double planets sharing an atmosphere
If two planets were tidally locked and shared an atmosphere, as described in this question, what would the weather patterns of the planets be like? What weather patterns would form, and could these ...
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1answer
123 views
What would the moon look like if its orbit was highly inclined?
How would the phases of the moon change depending on the inclination of its orbit with respect to its primary's equatorial plane? Earth's moon has an orbit that is rather close to the ecliptic, but ...
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4answers
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Would mining huge amounts of resources on the Moon change its orbit?
Imagine that humanity builds mining facilities on the moon. We know that the moon has Helium-3 which could be used as fuel for fusion reactors. Also, there are a lot of other resources which could be ...
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1answer
162 views
Habitable world orbiting a gas giant orbiting a gas giant
How likely would a habitable world be that orbits a gas giant that itself is orbiting a larger gas giant? Assuming one exists, what are the likely conditions?
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1answer
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Planet with big axial tilt, but very close to its star
It is known that when a planet orbits very close around its star, the tidal effects will soon (on an astronomical scale) force the day and the year of the planet to have the same length, making the ...
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3answers
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Is it possible for the remnants of a planet to be locked in orbit around another in a dual planet system?
I'm envisioning a double-planet system where both orbit around a central point. One planet is approximately Earth-sized, while the other is about one-tenth the size.
One of the planets (the smaller ...
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3answers
82 views
Types of life on a planet in a sun-synchronous orbit?
Basically, a sun-synchronous orbit is where one side of an object is always facing a star as it revolves around it (much like our Moon is, which is where the phrase 'dark side of the moon' originates')...
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1answer
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Orbital Resonance & Tidal Locking
I'm building a habitable world tidally locked to a red dwarf star. In order to affect a tide and other weather patterns I was going to have another planet closer to the star that has an orbital ...
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5answers
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160 Year Solar Orbital Period & 1.9 Year Moon Orbital Period - Is it possible?
A defining factor of my world is the hardships inhabitants have to face when surviving long seasons. Due to the extreme length of a year, time is largely measured by moon cycles. I need to make sure ...
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1answer
272 views
Only changing the mass of the moon, how much can lunar mass increase before the Earth becomes uninhabitable?
Bonus: How much would the increase in lunar mass increase average tides? & which factors would cause the Earth to become uninhabitable?
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5answers
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Tides with 3 Largish Moons
I would like to have an Earth-like planet (~Earth gravity, ~Earth day, ~Earth year, and liquid water oceans) with extreme variance in its tides. I want the lowest tide to reveal about 30 miles of ...
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1answer
291 views
In a world with 12 moons but NO sun, how to define a day? [closed]
I made the map of my fantasy world before thinking about the physics, as you can see bellow the art!
I'm interested to understand how to decide which moon is in the sky at a given moment, if it's ...
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14answers
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How can I launch a projectile to hit something in orbit, using only geological structures and power sources?
As an ancient organism whom currently occupies a large chunk of a planet beneath the surface, I have a pesky issue with an invasive species. These humans have decided to colonize my home, mistaking it ...
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2answers
260 views
Can a planet's atmosphere be in orbit around the planet? [duplicate]
Imagine a planet somewhat like Saturn except that its rings are its atmosphere instead of rocks and ice.
Is this theoretically possible?
(a) If so, what conditions would need to be true and what ...
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4answers
421 views
Would a portal to space enable propulsionless orbital launch
I'm writing a story about a race that has space travel capabilities without rocket technology, instead is using a portal to space and was wondering whether it's possible for them to put something in ...
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1answer
94 views
Could a synchronously-rotating planet in the goldilocks zone exist? [duplicate]
An earth like planet in terms of lots of water and an atmosphere. The liquid water on the sunny side would evaporate due to the extreme heat and the snow and ice on the dark side would never melt due ...
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2answers
158 views
Calculating an eccentric enough orbit to allow a dip into atmosphere and escape again
How would I calculate if it is possible to have an eccentric enough orbit around a gas giant to dip the periapsis some depth(how deep?) into the atmosphere of a gas giant like Jupiter or Saturn and ...
