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Instant-use add-on functions for the Wolfram Language

Function Repository Resource:

 ConvertECIToMSE

Source Notebook

Find the position relative to the mean spherical Earth (MSE) for a point in the Earth-centered inertial (ECI) coordinate system

Contributed by: Kerry Michael Soileau

ResourceFunction["ConvertECIToMSE"][date,p]

finds the latitude and longitude relative to the mean spherical Earth for a point p in the ECI coordinate frame at the moment defined by date.

Details

The mean spherical Earth is a sphere centered at Earth's center, rotating once per sidereal day, and having radius equal to the mean radius of the Earth.

Examples

Basic Examples (2) 

Find latitude and longitude on the mean spherical Earth:

In[1]:=
ResourceFunction["ConvertECIToMSE"][ DateObject[{2022, 9, 15, 14, 44, 0}, "Instant", "Gregorian", 0.`], {Quantity[-4425.817668153241`, "Kilometers"], Quantity[-2693.2774506502606`, "Kilometers"], Quantity[4338.165678929191`, "Kilometers"]}]
Out[1]=

Find the current latitude and longitude on the mean spherical Earth and display its position on a map:

In[2]:=
position = ResourceFunction["ConvertECIToMSE"][ Now, {Quantity[-4425.817668153241`, "Kilometers"], Quantity[-2693.2774506502606`, "Kilometers"], Quantity[4338.165678929191`, "Kilometers"]}]
Out[2]=

Possible Issues (1) 

The center of the Earth cannot be projected to the MSE frame:

In[3]:=
ResourceFunction["ConvertECIToMSE"][ DateObject[{2022, 9, 15, 14, 44, 0}, "Instant", "Gregorian", 0.`], {Quantity[0, "Meters"], Quantity[0, "Meters"], Quantity[0, "Meters"]}]
Out[3]=

Publisher

Kerry Soileau

Requirements

Wolfram Language 13.0 (December 2021) or above

Version History

  • 1.0.0 – 06 June 2023

Related Resources

Author Notes

GeoPositionXYZ gives information about a position on an Earth-fixed inertial system. My function's inertial system is inertial with respect to the stars, so it is not Earth-fixed.

License Information