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= Radiation belt transit times to GEO and the Moon == | = Radiation belt transit times to GEO and the Moon = |
Radiation belt transit times to GEO and the Moon
LibreOffice spreadsheet here
Excel/97 version here. Not sure about whether this will work with your version of Excel, this is the translation made by LibreOffice, and I don't have any computers that run any of the myriad versions of Windoze or Excel.
LibreOffice is available for free download here.
I used the equations here on the server sky website.
- 1 from the altitudes and Earth's equatorial radius, compute radii
- assume all orbits are circular equatorial. Inclined orbits require an expensive plane change, best done after circularization
- 2 Given apogee and perigee and the Earth gravitational parameter, compute
- Semimajor axis
- Eccentricity
- Orbit angular velocity
- 3 Given the radius of the lower and upper bounds of the inner belt (altitudes 200 and 1000 km), compute
- true anomaly angle
- eccentric anomaly angle
- mean anomaly angle
- 4 from the difference in the mean anomaly angles and the orbital angular velocity, compute transit time
Conclusion: an transfer orbit from ISS altitude to GEO takes 21.8 minutes to pass through the inner van Allen belt, and 18.2 minutes to pass through on the way to the Moon.