Do planets share the same 'second focus' in their elliptical orbits?

No the do not. The roughly share the same 'first focus' where the Sun itself is located, but even this point moves around a little bit. Like a hula-hoop, one focus is anchored by the sun, and the orbit of the planet 'precesses' around this focus over thousands of years.


Copyright 1997 Dr. Sten Odenwald
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