Astrometric Binary

An astrometric binary is a class of binary systems made up of a visible primary object and an invisible secondary object. The secondary object is Yin and the primary object is Yang.

Only one object is visible in an astrometric binary because the other object is hidden in darkness. Therefore the visible object is light (Yang) and the invisible object is darkness (Yang).

An astrometric binary system is the opposite of a binary star, in that a binary star is made up of two visible objects and an astrometric binary system is made up of one visible object and one invisible object.

A binary system is a tree: the tree of life. This means that the celestial sphere is a garden and the binary systems are the trees in the Garden. The trees are binary stars, binary black holes, galaxies, asteroids, brown dwarfs, neutron stars, etc.

In a binary star, the root and the crown of the tree of life are the two stars (the two objects).

The primary object is the crown of the tree or the first star and the secondary object is the root of the tree or the second object. Here, the crown and the root are equal to Yinyang because the crown is light as well as the root.

Although the two objects constituting an astrometric binary are Yin and Yang respectively, astrometric binaries are Yinyang (the tree of life) because they are the reality of a living tree. We see only one object ((the crown) because the tree is planted and the root is concealed in the ground.