# Questions tagged [astrophysics]

Questions involving the physics of the universe, especially the nature of astronomical objects, energy fields, and/or regions, rather than their positions or motions in space.

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### Why are the magnetic poles of a pulsar so far off the rotational axis, yet stable?

My understanding is that a pulsar is a neutron star whose magnetic poles don't coincide with the rotational poles and whose magnetic poles sweep through Earth (allowing us to hear radio noise). If we ...
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### The Poynting Robertson Effect

In the Poynting Robertson effect, it says in general, the Poynting Robertson effect is caused by the fact that objects like dust re-emit the light they absorb. Is that correct? Is this effect weak? ...
57 views

### Flux from the Sun on the Earth using the Stefan-Boltzmann law

What is wrong with this computation, plase? I am getting the result of 4291.65 W m^{-2} instead of 1361 W m^{-2}. Thank you very much ...
337 views

### The consequences and the mechanisms of a shift of the Earth away from the sun

First premise: I have already made this question in the worldbuilding section, but since it is a very specific question many have recommended me to write in the astronomy section so here we are. ...
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### Why can't dark energy be considered a 5th fundamental force?

So I have recently been researching for multiple articles about fundamental forces, currently there are just 4 forces: Gravity Electromagnetism Strong nuclear force Weak nuclear force So far there ...
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### Crop a FITS file in shape of another

I have a FITS file, let us say file A. I have another FITS file, file B. File B has a smaller footprint than file A. I want to crop file A in shape of file B. How do I go about doing that?
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### When analyzing a particle moving at Kepler speed, √(GM/R) in a planetary magnetic field, do we need to convert it to angular speed, √(GM/R^3)?

A charged particle is moving in a planetary magnetic field, in a spherical polar coordinates which is corotating with the magnetic field. To solve the equations of motion numerically what would be the ...