Questions tagged [astronomy]
For questions related to planets, moons, stars and other celestial objects, and their motion on the sky.
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What's the maximum mass for an Iron Planet to have a magnetosphere like Mercury's?
I'm designing an iron planet which migrated into its habitable zone. Basic research told me iron planets cool off too quickly to have a magnetic field, so initially I was looking for ways native life ...
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Effect of molecular clouds on space travel and civilization
To What Extent are Molecular Clouds Geographic Barriers in Space?
In a sci-fi universe I've been working on for quite a while, I have different civilizations that are initially unaware of each other's ...
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How visible would stars be from a planet orbiting an M-class star?
I have a planet orbiting at 0.2067 AU around a M-class red dwarf of mass and luminosity 0.4037 Msol and 0.0286 Lsol, respectively. The planet has an atmosphere of 93% CO2 and 3 atm. What I wonder is, ...
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Solar Flux required to boil oceans?
What amount of stellar flux that a planet receives is required to boil away all oceans on said planet? We're thinking of Q🜨 (Earth = 1.00 Q🜨). For comparison: Venus ~ 1.93 Q🜨, Mercury ~ 6.57 Q🜨, ...
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How axial precession affects the night sky
I am working on the model which can visualise how the night sky change over time (from observer's point of view). I was thinking how axial precession affect positions of stars and planets on the night ...
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What Stars Do I Need to Make a Railgun?
Alright so I have come up with this idea for the primary weapon of a particular class of mages in my fantasy world: the Railgun. These mages are called starborn because, when they are born, they are ...
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If Earth were located at 1.1 AU from the Sun, would this affect the two zenithal passage days in the Tropics?
I am designing calendrics for an Earth-like planet located 1.1 AU from a Sun-like star. On Earth, on April 30th and August 13th, the Sun appears to pass directly overhead between the Tropics of Cancer ...
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Would an increase in star density affect the "Goldilocks Zone"?
Let's say that there's a solar system that matches the description of Sol exactly, save for the fact that it's 20,000 light years closer/farther to the galactic center.
Would the zone of one ...
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Could a captured planet end up in the habitable zone of a new star system?
Is it possible for a planet to be ejected from one star system and end up in the habitable zone of another? Or do captured planets always end up in wide, eccentric orbits?
I guess in the vast expanse ...
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How might planet size affect volcanic activity?
I'm working on a project involving the evolution of life on different hypothetical habitable planets. In imagining different atmospheres on planets of different masses, I'm wondering how a planet's ...
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How magnitude affects angular diameter/resolution
Let's say you look at two relatively dim stars in the night sky. They are close to each other, but they are far away enough that you can distinguish one from the other. But what if one of them is much ...
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Is it realistic to have 7 months in a year?
I'm aware of the property of the number $2520$. It's divisible by all integer numbers from $1$ to $10$.
One of the factorizations of $2520$ is $7×360$.
It came to my mind to make a habitable planet ...
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Is it possible for polar nights at one pole to be 8 & 1/2 months long without significantly messing up the climate?
Is it possible for polar nights at one pole to be 8 & 1/2 months long without significantly messing up the climate?
The length of polar nights at the south pole from what i know is a week longer ...
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Is it possible for a planet about 1/5th larger than earth in radius to remain earthlike?
The planet in question has a radius of 7947km, volume 1.9408 times as large as earth, & a weight about 1.55377 times that of earth.
I want the planet to be earth like, or at least earth like ...
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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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Could a slow rotating planet combined with high density atmosphere create high winds?
I am trying to design an alien ecosystem around a K type star. My idea was to have purple plants and high wind atmosphere so originally I wanted to make it tidally locked. However after watching some ...
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Trinary star system - Tidal locked planet [closed]
I'm trying to build a world where an earth-like planet is tidal locked to a sun in a three star system, where the other two would orbit each other in the center (being the central mass of the system). ...
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What are some pseudo-scientific ways to explain the qualities of a yellow dwarf hyperstar?
Basically, in my stories, there’s a habitable, Earth-like planet called Ozarvis 32. It is the 32nd planet from the star of the Ozarvis Stellar System, which has 68 planets, 12 of which are in the ...
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How do I make an Earth-like habitable planet tidally locked to a red supergiant (class L or M)?
Assuming tidally locked planets have the potential to be inhabitable: Is there any way for a planet of Earth-like size to become tidally locked to a red supergiant of class L or M?
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What could cause a star system's protoplanetary disk to fragment more easily?
Essentially I'm looking to fill a star system with as many planetary bodies as I can, and I figure the larger the objects get, the more planets get crushed together or flung out of the system. There's ...
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How many giant planets could form in a hierarchical triple star system?
The system in question has a very close binary pair of 2 G-type stars, a G9V and a G7V, orbiting at about 0.2 AU, with a K2V star in a far orbit about 300 AU out around the both of them. There is a ...
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What stellar temperature, orbital distance, and eccentricity is needed to create an Earthlike orbital planet with a last glacial maximum climate?
I am creating an Earthlike planet with a year length of 515 Earth days and 9 Earth hours. I am aware that Kepler's third law of planetary motion states that warmer stars are needed for longer orbital ...
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How fast would this astronomical macromorph be?
I’m taking inspiration from Robert A. Freitas Jr.’s theory about alien metabolisms based on gravity rather than electromagnetism. He imagines astronomically sized beings that derive energy by ...
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A brown dwarf world
I’m thinking about making a detailed world on Luhman 16 B (not around the star, right on it). This brown dwarf's mass is 28.6 times that of Jupiter and has a radius 104% that of Jupiter. It has a ...
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What star would cause a planet to have white plants?
Okay, I'm trying to make a planet that has at least part of its surface, or at least part of its underground, habitable for humans (breathable atmosphere at a suitable pressure, a suitable level of ...
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Why does daytime on my planet resemble twilight/dusk?
The setting is science-fantasy, so there are some unnatural features that dictate the properties of the setting, but I'd rather not rely on it.
So basically this planet is very similar to our own, but ...
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Is a p-type binary system with two suns and two moons possible? [closed]
I want to have a fantasy setting with two suns and two moons. Ideally, the stars would be 5 million km apart, orbit each other every 10 days, and pass in front of each other every 5 days, creating an ...
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Trojan Planet Skies
A few questions here have broached the possibility and survivability of life on a Trojan planet, a planet that exists at the Lagrange point of a larger celestial body. In this particular question, the ...
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How long would it take us to detect that the earth had been enclosed in a shell 1 light year in radius?
Suppose we put a shell around the solar system that displays a 2D image of the rest of the universe on its inner surface. What year would we have had telescopes powerful enough to determine that this ...
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Does my binary planet make sense?
I have a binary planet as the setting for a sci-fi story, and I would like to know if this system makes sense or if there are any major flaws. I am also open to suggestions for improvements.
Here is a ...
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How would an observer from a moon the mass of Earth orbiting a planet 81.3 time more massive be able to tell that they were orbiting with 1660's tech
For questions sake assume that this moon is a perfect recreation of Earth on January 1st 1660 and that the planet looks identical to our moon on the same day.
The Planet would have a mass of 81.3 ...
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How could an iron planet be geologically active?
So I have an iron planet, and its name is Randall.
Since Randall is an iron planet, he is basically the core of a planet with no crust/mantle, and very few silicates. Now, I, the creator outside of ...
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What is the maximum amount of land (percentage-wise) a habitable planet can have?
Earth is our only example of a habitable planet. The surface of Earth is 29% land and 71% ocean. I am wondering what other land ratios can create a habitable planet.
Half a billion years ago, Earth ...
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What feature of Earth would be most likely attract the interest of aliens?
What feature of Earth would be most likely to attract the interest of a curious alien intelligence searching the Milky Way marking the Earth as an unusual world and how close would they have to be to ...
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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 ...
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What dictates whether an orbit gets disrupted or stabilised due to an orbital resonance?
Context:
I've got an asteroid belt analogue situated between a Gas giant and a Super-earth. I knew about resonances, so I started calculating them and placing some of them in the belt, especially ones ...
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In what detail can you examine a distant planet's atmosphere?
Scenario
We've got a terrestial exoplanet three times the size of Earth, 1800 light years away and with an atmosphere similar in composition to Earth's. It is determined via studies that atmosphere ...
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Jupiter's moon Europa - is it possible to colonize Europa? [closed]
So basically, I have to write a thesis paper because I'm in the last year of high school. It is an independent research project and the culminating work of my studies in school, so it represents my ...
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Could a terrestrial planet have a stable orbit of rings? [duplicate]
Planet Phileas, similar in size to Earth. Fourth star in a binary star system with a p-type orbit.
Changes may be necessary and I'm open to constructive criticism. This question includes two parts. ...
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How many days in a week, and weeks in a month, would be needed for this specific lunar cycle?
So, this world has three moons.
Blue, Red, Yellow.
There are eight months in the year. Each month has a unique "full moon" combination resulting in a different colored sky. That is the ...
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433 Eros hits the Moon. How much rock hits the Earth?
A la this image I made.
The "how" (nuclear pulse drive "adjusting" Eros's orbit at its aphelion) and "why" (uber-sized Rods from God) isn't particularly relevant — all ...
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How fast can a moon pass overhead?
For purposes of realistic, but otherworldly visualisations of foreign worlds I'm wondering what the fastest speed is that a moon will track through the visible sky, as observed from the body of a ...
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What are the challenges of living on a planet with constant meteor showers?
I have been thinking of a planet that has or is experience(ing) a lunar holocaust; moon broke into pieces and many of them fell to the planet. Initial disasters probably caused a massive mass-...
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What would be the climate of a planet with very frequent hurricanes?
I'm writing a planet where the weather is always stormy. This planet has hurricanes and monsoons and huge thunderstorms and tornadoes on a weekly basis. The good news is that there are very few ...
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What would the climate be like on highly volcanic planet?
I'm writing about a planet that is harsh but livable. This planet is covered with mountains and active volcanoes. Far more volcanoes than what exists on Earth. It is more like Venus but is much ...
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What would happen to clouds that existed in the upper atmosphere?
I am trying to determine, on a planet with extreme weather, the conditions and constraints applied to seeing weather patterns from more than 500 miles away (as a miniscule layer on a flat horizon). I ...
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How can we prevent the Earth being scorched and swallowed as the Sun grows and eventually enters its red giant phase?
The Sun is slowly growing more and more luminous.
As a result of these processes, multicellular life forms may be extinct in about 800 million years, and eukaryotes in 1.3 billion years, leaving only ...
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How close would a black hole need to be for humans to have discovered it before theorizing it?
Black holes were first seriously theorized in the early 20th century, but it took many decades before one could be observed; depending on your definition of "observe," this may have occurred ...
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Is there a way to find the dates that a solar eclipse happens while Ceres is in alignment with Earth? [closed]
In the game i'm working on the Earth was hit by a Coronal Mass Ejection during a solar eclipse. I'm looking for dates between 2100 and 2300 where a base on Ceres would be protected by being in the ...
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Retrofitting geocentrism - what replaces the star?
The goal is to devise a plausible geocentric system in appearance. However, for simplicity, we will need only to examine the one planet case. And more crucially, this one Earth-like body is to be the ...
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