Questions tagged [radius]
The radius tag has no usage guidance.
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Most accurate way of measuing the radius of a rubble-pile comet in an N-body simulation?
I have written an N-body simulation (close to finished) in C++ which focuses on the tidal disruption of comets.
I allow comets to be constructed in 2 ways:
Via my HCP (hexagonal-closest-packing) ...
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Effective radius from astropy sersic profile
I would like to integrate the 2d Sérsic profile of the astropy library to check the half light radius, but I have some issues.
First, I create a simple profile:
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How to use SExtractor to calculate Petrosian Radius?
I'm using Sextractor to run some benchmarks on the code I'm working on.
I'm mainly focused on Petrosial Radius (PETRO_RADIUS).
I have two main questions that I could not find in the documentation:
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What is going on with this (sub?) brown dwarf WISEPA J174124.26+255319.5?
In this Wikipedia article, it details about a T9 class brown dwarf named WISEPA J174124.26+255319.5.
Apparently, this brown dwarf has 0.95 Jupiter masses, and 0.4 Jupiter radii (with rather low error)...
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Small Angle Approximation Discrepancy in Horizon Dip Angle
Let's get back to the classic astronomical problem of calculating horizontal dip angle using small angle approximations. Let, our observer is a point object situated at an height $h$ on the earth ...
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What is the maximum radius of an Einstein ring?
Is there an upper limit to how far out an Einstein ring can be visible? For black holes, is it a fixed multiple of their Schwarzschild radius?
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Finding stellar radii
Is apparent magnitude of star, distance(in pc) and effective temperature enough to calculate its stellar radii or we need some extra information?
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Gravity inside a star?
Recently, I answered this question and need some clarification regarding the gravity when within the radius of a star. I thought that, when something is inside a star (ignoring drag), it will ...
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How Can I interpret this particular light curve without reading data on the side
There is only one dip in flux recorded. How can I interpret this particular light curve and find planetary radius
https://exo.mast.stsci.edu/exomast_planet.html?planet=55Cnce
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How can I find the radius of a exoplanet using doppler spectroscopy [closed]
I have the stellar and planet mass, planet velocity, radial velocity of star, stellar semimajor axis.
How should I go about to find the radius of this exoplanet?
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Simple definition of Bondi Radius
Can anyone help me by defining what is exactly Bondi Radius? I have searched far and wide but the results are very complicated and so far I have only rough idea of it but I just cant explain it very ...
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How can the radius of a star be measured using parallax?
The radius of Betelgeuse was measured using parallax. From the Wikipedia article:
the estimated parallax from the Hipparcos mission was 7.63±1.64 mas, yielding an estimated radius for Betelgeuse of ...
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