Questions tagged [astronomy]
For questions related to planets, moons, stars and other celestial objects, and their motion on the sky.
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How to calculate the albedo of a gas giant
My gas giant has the follow properties (where $_J$ refers to the properties of Jupiter):
Mass: $3M_J$
Radius: $1.5M_J$
Surface gravity: $1.33g_J$
Density: $0.88\rho_J$
Atmospheric composition:
22% ...
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When is the earliest a planet in an eccentric near-polar orbit of Sol could have been detected?
I am currently working on a setting involving our solar system (the Sol system) containing several fictional planets, in addition to all of the real major planets; This question focuses on one of ...
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Are there any tools/methods for visualizing the sky of my planet within a custom solar system?
I'm a long time lurker and have used alot of information gathered from posts here in building my own fantasy setting.
What I need help with is as follows. I've got a planet with several moons and ...
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How close could solar systems be in ideal conditions
Let's say a god had wiped the universe clean and filled it with copies of our solar system. How close could those solar systems be to each other with every version of Earth still more or less being ...
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Recommendations for which red dwarf stars to include in a realistic sci-fi setting
I have decided to use an accurate representation of real stars within 50 lightyears of the sun in my setting. I'm ok with adding most of the major stars in this region. The problem is this region also ...
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How can I visualize how bright the night would look with an sky object at a certain apparent magnitude?
I have the apparent magnitude of how bright my moon would be when it is full. The problem, however, is that magnitude is just a number. I looked online, but I couldn't seem to find a way to convert ...
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What is the lowest mass habitable planet?
I am interested in the possibility of low mass habitable worlds, so I am curious in regards to what is the lower limit of mass required to maintain earth like-conditions and life. Specifically, I am ...
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Can a mercurian mass exomoon and or planet support earth like life?
I am interested in the possibility of low mass habitable planets. My major question is what conditions would need to be in place for a roughly mercurian mass moon or planet to be habitable. My ...
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How would a lonsdaleite moon look?
If the outer layer of the moon 1m deep were suddenly transformed to solid lonsdaleite, becoming a perfect sphere and the layer under the lonsdaleite suddenly turned blue striped with green(ignore how) ...
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Plausibility of creature design: complex organisms on surface of Europa?
Is it too unbelievable to include in my science fiction story about space exploration the discovery of complex organisms (sessile "ice worms") inhabiting the extremely cold, near-vacuum of ...
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What is the smallest size for a heavy stable galaxy?
As Douglas Adams said, Space is big. This galaxy alone is 100,000 light-years in diameter. The nearest Solar System is over 4 light-years away. But what if space within a galaxy was less big?
I'm ...
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What kind of cosmic event could justify the entire Solar System being uninhabitable in the near future (1000 years or less)?
Edit: In my story, characters possess very convenient and very powerful terraforming technology (so powerful that some characters are able to briefly survive on an asteroid). An important part of the ...
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In an eclipsing binary orbited by an Earth like planet, would the drops in brightness be noticeable?
An eclipsing binary is a binary star system that periodically eclipses one another. There is a drop in total brightness when the primary eclipses the secondary and a smaller drop when the secondary ...
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Why would the Seasonal Cycle and Orbital Period of a planet not correlate? [duplicate]
My goal is to create a fictional Planet, which has a 4 year-long orbital period around it's star, but still goes through a 1 to 2 year long seasonal cycle like earth. Also the axial tilt should be ...
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Reflective nebula
I have the beginning of a short story where we follow a marvelous astronomical discovery.
An object 1000 light years away with reflective properties.
Plotpoint: Humanity can use this to see what ...
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