How Did Libra Get Its Name?

In Latin, Libra means “weighing scales.” Even long before Roman times, Sumerian sky watchers named this constellation “Zib-ba An-na,” or “the balance of heaven.” Arab astronomers called the Libra constellation “Zubana,” which can mean either “weighing scales” or “scorpion.”

The constellation of Libra lies directly west of the constellation of Scorpius, and because of this, some ancient astronomers mistakenly translated Libra as “the claw’s of a scorpion.” Scholars explain this dual meaning by noting that in ancient times, weighing scales resembled a scorpion hung upside down. In Greek mythology, Libra was depicted as the scales of justice, held by the goddess Astraea, who was represented by the nearby constellation Virgo. Chinese astronomers called the Libra constellation “Tien Ching,” meaning “the celestial balance.”

The stars in Libra have Arabic names. Most of these reflect Libra’s proximity to the constellation Scorpius. For example, Zubeneschamali means the scorpion’s northern claw; Zubenelgenubi refers to the scorpion’s southern claw; and Zubenelakrab means the scorpion’s shears.

The sun moves through Libra from September 23 to October 22. This time period immediately follows the autumnal equinox, when day and night length are balanced at 12 hours each. Also noteworthy is that Libra influenced the abbreviation “lbs” to stand for pounds in the English language.