The Magnetosphere Size property represents the size of an object's magnetosphere, the region of space where particles will be affected by the object's magnetic field.

The size of the magnetosphere, Rmag, sometimes called the Chapman-Ferraro distance, is calculated relative to the object's radius, R, using

where B is the strength of the magnetic field, P is the total stellar wind pressure, and μ0 us the vacuum permeability constant,

Property Details


The Magnetosphere Size property is located in the Magnetic Fields section at the end of the Composition tab in the object's properties panel. This property will only be visible for Planetary Body objects.


Magnetosphere Size can be viewed and edited using the following units:

  • Milky Way Galaxy radius (milky way) = 5.5×104 light year
  • Parsec (parsec) = 3.08568025×1016 m
  • Light-year (light year) = 9.46073047×1015 m
  • Astronomical Unit (AU) = 1.495978707×1011 m
  • Solar radius (sun) = 6.955×108 m
  • Lunar distance (lunar dist) = 3.844×108 m
  • Light-second (light sec) = 2.99792458×108 m
  • Jupiter radius (jupiter) = 6.9911×107 m
  • Earth radius (earth) = 6.37101×106 m
  • Moon radius (moon) = 1.7371×106 m
  • Kilometer (km) = 1000 m
  • Meter (m) is the SI base unit for length
  • Centimeter (cm) = 0.01 m
  • Millimeter (mm) = 0.001 m

Simulation Effects

The value of the Magnetosphere Size property will affect the size of the displayed magnetosphere when the Show Magnetosphere toggle is on. If the magnetosphere is smaller than the object itself (i.e., Magnetosphere Size is less than 1), the magnetosphere will not be visible.

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