There's no such thing in Tango, each partner has their own axis which themselves are always changing.
And to make the point differently, the only way an axis can be shared is for the man to stand on one leg and the woman to stand on one leg on his head! Or the other way round.
This is a problem actually caused by the use of the word axis in describing the way we stand in balance on one leg and in moving create new axes. But that use is accepted and understood as a shorthand for moving yet being balanced individually.
If you insist on re-using the word for two partners turning simultaneously as if they are both on the circumference of a circle, can we agree to call that an axis of rotation.
In purely astronomical terms, the
rotational axis is the one within the center of a body that the body spins on. The path of travel external to the body is the
revolutionary or orbital axis. In other words, the earth
rotates on its own axis, and
revolves around the sun.
Using that model, "rotational axis" is the term for
turning in place ("spinning" on your own axis) NOT the term for going around the perimeter of a circle. If two people are both going around the path of a circle, the center of which is between them, they are both
revolving around a single axis. (as satellites do to a sun)
So if you want to define axis as meaning only the one running through the body of the individual, and use an alternate term for the external axis that the couple may be using for a pair turn (or one partner being the center for the other partner going around) then
rotational axis would be the wrong choice (and still misleading) since it actually means the axis of the individual unit.
Frankly, "axis" is used to mean both the individual dancer's vertical balance line
and the center point of various turns, regardless of whether that turn is a rotation or a revolution...(or both... usually there is also rotational turning going on during an orbit)
Railing against the use of the term "axis" to mean the center point of a turn is futile. Its
already a common usage and has been for awhile. We didn't invent it here. Science uses the term in both ways, and so do dancers. You might as well get used to it (and the ensuing confusion) because you aren't going to be able to stop this train.. the world will keep on spinnin'.
