The Moon is in a sort of cosmic balance tonight. It’s passing through Libra, the balance scales — the only constellation of the zodiac that doesn’t represent a living thing.

But the scales are associated with two living things — Virgo, which represents a goddess, and Scorpius, the scorpion. In various cultures of the Mediterranean, the stars of Libra were attached to one or both of those figures.

In ancient Babylon, the stars represented a scale held by Shamash, the Sun god. He was also the god of truth and justice. The scales helped him maintain a “balance” on Earth and in the heavens.

And there may have been an astronomical reason for thinking of the stars of Libra as “in balance.” Until about 2700 years ago, the Sun passed across those stars at the fall equinox — a time when day and night are roughly the same length — they’re in balance.

Libra also was identified as the claws of the scorpion, which is on the opposite side of the constellation. The names of Libra’s brightest stars still reflect that heritage: Zubeneschamali, the northern claw, and Zubenelgenubi, the southern claw, which is quite close to the Moon tonight.

The Greeks maintained the connection to both the gods and the scorpion. Libra wasn’t depicted as a separate constellation until a couple of thousand years ago, in Rome. Yet it maintains the links to its heritage — the scales of justice, and the claws of the scorpion.

Script by Damond Benningfield