All Questions
Tagged with astrophysics planet
26
questions
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Project Analog Hypothetical Planet
For my story Project Analog, I was wondering if a hypothetical planet (Let's call it Suria). It has the same size and conditions as Earth with the same axis, tilt, and rotation, as well as one moon. ...
2
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1
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How to estimate perturbations from other planets in Apsidal Precession
I am developing a fictional system which I want to calculate to as much detail as I can. Thus I have a question about astrophysics and astrophysical formulae.
I know that Apsidal Precession is ...
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1
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Is the magnetic permeability (mu_0) necessary in the expression for planetary magnetic field?
To numerically analyse the Lorentz effect due to the magnetic field, say, radial component on a charge particles which of the expression would be correct, $\{ B_r = \frac{2R}{r^3} g_1^0 \cos(\theta) \}...
5
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Can rings last around planets indefinitely?
Apparently, Saturn is losing its rings (https://weather.com/en-IN/india/space/news/2023-05-04-saturn-is-losing-its-rings-webb-may-tell-us-how-long-they-have-left) However, is there any way or ...
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3
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920
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why does earth have speed?
I understand that Earth has a quite big speed such as it ends up around the orbit. The sun can't really attract it till the end due to Earth's speed and earth really can't escape due to gravity, hence,...
4
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Formation of a non-Sol Oort cloud with high mass planets
Based on recent developments in astronomy, pertaining to a greater degree of measurement, the mass of the Oort cloud around Sol is apparently only about 1.5 times the mass of earth, in contrast to ...
6
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287
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What value of density would a planet need to be classified as a mini-Neptune?
EDIT: well, now I have more
For reference:
A terrestrial planet is a planet that is made out of silicates and metals.
A Mini-Neptune is, as far as I know, the smallest type of giant planet (arguably,...
3
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How do we differentiate between a star or planet and noise introduced due to equipment?
I understand that differentiating between celestial bodies and noise due to equipment is a fundamental problem in astronomy. I also understand that we solve this problem by looking at something called ...
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How does a planet-sized robot standing on a planet affect its gravity? [closed]
I originally asked this at the sci-fi exchange but was told it was off-topic as it was about real-world science.
Here is a picture of Unicron standing on top of the planet Cybertron, as written by ...
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4
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325
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Tilting cycle vs orbital cycle of earth
Common sense tells us a year is conveniently divided exactly into four seasons. I'm wondering whether that means the earth's tilting cycle is equal to its orbital cycle. If so, there must be a reason. ...
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To show perihelion precession motion of Mercury in Python with matplotlib
I'm trying to make it more general code so I can trace even a parabola or hyperbola for $e=1, E=0$ and $e>1, E>0$ respectively. And after achieving that general code I want to make the same code ...
4
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Largest non-hot gas giants
Excluding 'fluffy' or 'puffy' gas giants that are 'inflated by heat from their stars, what is the maximum radius of a gas giant planet. I keep reading things like "...Jupiter is 'about' as big as ...
4
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350
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Warm jupiter vs hot jupiter, fluffyness
If Jupiter was orbiting at 1AU, replacing Earth, but everything else in the solar system remained as it is currently, how much would the increased heat from the sun increase Jupiter's radius?
In ...
2
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1
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81
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Why are gravitational perturbations stronger at larger semi-major axes?
Why are mechanisms such as the Kozai-Lidov effect more prominent at at large semi-major axes?
If we had a binary system of a primary and secondary body, with the third perturber as the Sun. Why is it ...
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210
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Are large body orbits self correcting?
If a rogue planet disrupts Earth's orbit slightly to cause a long winter or summer will the Earth's orbit normalize back close its original orbit over time? Could a Planet X or some other elliptical ...
2
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Why does the axial tilt & the rotation speed of Saturn & Jupiter vary so much?
I have seen Jupiter and its 4 largest moons in a telescope, several times. The moons are always aligned in a line. This is fine. Very interesting. But.. in case of Saturn, not only that we can see its ...
6
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What is the reason the Jovian planets are in descending order of size?
Is there any scientific reason for the jovian planets to be in descending order of size or is it purely coincidental? In terms of radii it goes Jupiter, Saturn, Uranus and Neptune.
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Property of elliptical orbits
I've studied that the major axis of a planets orbit = ( radius of perihelion + radius of aphelion) . But then how can we calculate the value of the minor axis if we are provided with the values of ...
6
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Kepler and the Sun position
When Kepler went to Tycho Brahe, he learned that Tycho Brahe was using the mean position of the sun to note down the position of Mars. Well, Kepler needed to convert these datas of Brahe to do his own ...
9
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211
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Period coincidence of Planet Nine with furthest Kuiper belt objects
A lead scientist of the Planet Nine theory said that "The period with which it goes around the sun is a rational multiple of the periods of all the furthest Kuiper Belt objects"
To what degree of ...
2
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1
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140
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On orbital mechanics of evaporating planets
A planet orbits around its sun on an elliptic orbit, and loses mass slowly due to evaporation. How will the parameters of the orbital ellipse change as a function of time?
Could we do a generalisation ...
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201
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Is it possible to know if a planet is located in the Habitable Zone knowing it's properties?
Is there an equation that can give me the possibile distance of the planet from his star knowing planet's temperature (or other datas)?
I found this method for calculating the Habitable Zone but it'...
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Spheres in space [duplicate]
I know that gravity will turn a mass into a sphere, which is why planets and stars are that shape. But then we have asteroids and small moons which are not spherical. Such as a couple of Pluto's moons....
17
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Open problems in astronomy that an amateur (with a PhD in some other field) would have a chance of solving?
What are some open problems in astronomy that an amateur would have a chance of solving? Suppose the amateur has a PhD in some other field, owns a basic telescope, a set of filters, diffraction ...
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140
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Apocalypse on earth
What would it feel like on Earth if the Earth accelerated due to sudden changes in the solar system like ejection of another planet? Would there be giant tidal waves and other cataclysmic events?
6
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636
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Weight of a celestial body
How do astronomers find out the correct weight of a planet even though there isn't any direct means to weigh them? What technique do they use? Just curious!