Unanswered Questions
177 questions with no upvoted or accepted answers
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Is there an orbit around the earth that experiences a total solar eclipse by the Moon at least every month?
Is there a way to design an earth orbit so that it passes through the Moon's umbra with greater frequency than total solar eclipses occur on earth's surface?
What is the maximum frequency of eclipses ...
- 30.7k
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From a given latitude on Earth, how to calculate the number of days in a year when the moon is lit on the bottom?
From a given latitude on Earth, is it possible to calculate the number of days in a year when there is a wet moon , that is when the moon is lit on the bottom?
If, for example, I want to do the ...
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How do I calculate the flux density of a substellar object?
I am currently trying to generate photometric passband colors for brown dwarfs and planets generated through MESA (Modules for Experiments in Stellar Astrophysics). I believe I understand the ...
- 61
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The necessary conditions for driving winds with dust (Dust-driven Wind)
So lately I've read Intro to stellar winds (particularly chapter 7 Dust-driven winds) by Lamers & cassinelli, I forget how many times I've read this but I still don't really understand. So in the ...
- 123
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Where can I find definitions of minimum detectable flux sensitivity and signal to noise ratio?
I am struggling to find references that give precise definitions to these concepts. Even in PhD theses on the subject of gamma-ray astrophysics, for example, students do not define it precisely or ...
- 2,169
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What is the relationship between true anomaly and solar longitude?
So, my ultimate objective is to map solar longitude values onto a pseudo-Gregorian calendar. I thought this would be simple, but it has turned out to be anything but.
I have asked several questions on ...
- 141
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In a multi-planet system, what mechanism can cause the innermost planet's semi-major axis to increase?
I've been toying around with n-body simulations (using research-grade software) and I've noticed a particular effect in many of my simulations: In many arbitrary multi-planet systems I simulate, there ...
- 625
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Non-stable vs non-linear orbits
In orbital dynamics there are often two 'classes'- stable and non-stable, or periodic and non-periodic. Is this just a specific class of linear and non-linear harmonics? Would Klemperer's rosette ...
- 437
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Why are triple conjunctions in a resonance forbidden?
I was reading the Wikipedia article about orbital resonance and noticed that Laplace resonances forbid triple conjunctions. This seems to be supported by the Io-Europa-Ganymede system and the Nyx-Styx-...
- 30.7k
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Is it possible to infer information about the structure of the universe beyond the observable one?
Is it possible to infer information about the structure of the universe beyond the observable one, by observing its effects on the parts we can see? Can for example gravity from sources we cannot see ...
- 2,522
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Cosmology context plotting : Covariance matrix - Script to plot Omega_m vs Omega_Lambda diagram in Python
I have covariance matrices and Markov chains coming from the SCP (Supernova Cosmology Project) and I would like to plot all these data
in the particular diagram Omega_Lambda vs Omega_m or w vs Omega_m....
CommunityBot
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How to calculate orbital velocity of binary star?
I am trying to simulate the Alpha Centauri AB System. I built the simulation, it works flawlessly when trying to simulate our solar system, and I am now trying to simulate the AB System. I found all ...
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Orbiting around a common barycenter in Kurzgesagt video: "The Largest Black Hole in the Universe"
Observation
This video by In a Nutshell visualises the V723 Mon orbiting a smaller and heavier object/black hole named Unicorn. However, the animation shows Unicorn and V723 both orbiting some common ...
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What's the formula for change in argument of periapsis over time due to J2 perturbations for a geocentric satellite?
I'm trying to propagate the orbit of the ISS, but it became very clear to me very quickly that the J2 perturbations were nothing to scoff at.
A quick google search gave me the equation for the change ...
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Virial theorem for a binary system
I am trying to derive the virial theorem but for two stars orbiting each other. I know the derivation for the general virial theorem with i particles but I am wondering if there is a quicker or more ...
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