All Questions
Tagged with astrophysics planet
26
questions
17
votes
2
answers
1k
views
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 ...
- 171
9
votes
1
answer
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 ...
- 4,268
6
votes
1
answer
317
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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 ...
- 159
6
votes
1
answer
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,...
- 267
6
votes
1
answer
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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.
- 367
6
votes
2
answers
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!
- 1,064
5
votes
1
answer
203
views
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 ...
- 1,017
4
votes
1
answer
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 ...
- 379
4
votes
1
answer
137
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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 ...
- 379
4
votes
1
answer
104
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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 ...
3
votes
1
answer
86
views
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 ...
- 31
2
votes
1
answer
222
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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 ...
- 29
2
votes
1
answer
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 ...
- 141
2
votes
1
answer
42
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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 ...
- 376
2
votes
1
answer
81
views
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 ...
- 21