In article ,
(Axel Harvey) writes:
Is the "heliocentric" idea this: we choose a coordinate system in
which angular momentum is minimized?

I don't think so. Minimizing angular momentum would give a rotating
coordinate system (non-inertial) with roughly Jupiter's rotation
period.

A heliocentric system is one in which the Sun's linear momentum is
zero. A "barycentric" coordinate system makes the net linear
momentum of the entire solar system zero.

--
Steve Willner Phone 617-495-7123
Cambridge, MA 02138 USA
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