Questions tagged [planetary-systems]
Questions regarding the non-stellar objects gravitationally bound to a star or star system.
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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) \}...
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What's the simplest evidence for Kepler's first law?
What is the simplest explanation that provides enough evidence for the first Kepler law?
i.e. that planets around the Sun travel on ellipses with the Sun at one of the two foci.
Are the three Kepler ...
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The path of a particle in planet's magnetic field doesn't not seem to change with the charge of the particle. Can someone please check what is wrong?
I am trying to plot the path of a charged particle in a planet's magnetic field. For positive and negative charge (β=charge/mass) different solutions/paths are expected. But,I got the same solution (...
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How close does a double-planet have to be to provide magnetic protection to a smaller body?
A spinoff of my previous question, regarding the Orbital Stability of a Double Planet System. Imagine two closely-orbiting bodies with a semi-major axis of 79,250 km. One of which is 2M🜨, with a ...
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Orbital Stability of a Double Planet System
I recently found an article claiming a double planet system needs to be at least .5 AU from its parent star to be stable for billions of years. It was specifically talking about two same-mass bodies, ...
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Do planets affect their stars beyond causing them to wobble?
Are there any situations in which the existence of a planet measurably affects its star, aside from orbital wobble? I am curious about possible ongoing affects, not stuff that happened during stellar ...
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Radio signals between Mercury and the Moon during an eclipse
This is a hypothetical question. Thank you for your time and efforts.
A signal is sent from a transmitter on Mercury's surface while it is at its greatest western or eastern elongation. The signal is ...
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What are different forces acting on a planet which may be related to axial tilts?
In our solar system, we see that the axis of rotation of planets is tilted forex. The axial tilt of Venus is near 179 degrees. Venus, Uranus, and Pluto have large values of axial tilt(more than 90 ...
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Is the Michael H. Hart range for the Habitable Zone (Goldlocks Zone) still used?
We're having an argument on another site about the Hart definition of the CHZ. In 1979, Hart provided a very conservative estimate of habitable zone: 0.958 - 1.004 AU. This was used to substantiate ...
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Meteroids escaping the system
So the sun or any star has a certain gravitational pull. Technically the gravity extends infinitely only it will just become really small. If there is a meteroid around a star how do I calculate when ...
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Is the closest planet to another planet always the innermost planet?
In our Solar system Mercury is not only the closest planet to Earth on average but also, for the same reason, the closest planet on average to all other planets (Jupiter, Neptune, etc...).
Does that ...
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What's the expected distribution of planet masses in a given system?
Given that the mass of a planet at a given orbital distance r is dependent on the protoplanetary material in the neighborhood of r at the time of formation (assuming no planetary migration), what ...
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Jupiter's asteroid-like moons and planetary-systems around sub-brown dwarfs
Is it likely that any of Jupiter's small moons were formed in orbit around Jupiter or are they all captured asteroids? I thought of this question because I wondered whether the planetary-system of a ...
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Could a planetary system have a planet in its center? [duplicate]
Is it known, or at least known that it is feasible, to have a planetary system with a planet in its center, and not a star? Would it be too surprising to find a planet as barycenter and some stars as ...
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I have a question about the wording in a paper about a planetary system and comets
I was reading a paper. This is the paper:
https://arxiv.org/abs/2006.01711 (https://ui.adsabs.harvard.edu/abs/2020MNRAS.496.4979D/abstract
In the method section in the second paragraph there is a bit ...