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All scorpions have claws — except for the scorpion in the sky. As the constellation is configured today, Scorpius has a curving tail; a body, highlighted by bright orange Antares; and a head, marked by a short line of stars. But its claws are gone — and have been for thousands of years.
Yet the stars that represented the claws are still there. And they still bear names related to the scorpion, even though they’re officially in Libra, the balance scales.
Zubeneschamali and Zubenelgenubi are low in the southeast as night falls on May evenings, and skitter higher across the southern sky later on. They’re far above Antares, which climbs into good view by around 11 o’clock.
Their names mean the northern and southern claws. Those names tell us that, when Scorpius was first drawn, thousands of years ago, Zubeneschamali and Zubenelgenubi were part of it.
Later, though, they were assigned to Libra. That’s because the Sun stood in that part of the sky at the September equinox. Day and night are equal then — a time of balance in the heavens. So that region was named for the balance scales.
The Sun no longer appears against the stars of Libra at the equinox, though — and it hasn’t for almost 3,000 years. Instead, it’s a constellation over, near the western edge of Virgo.
Even though Zubeneschamali and Zubenelgenubi no longer officially belong to Scorpius, it’s still quite easy to see them as its claws — leading the scorpion across the sky.
Script by Damond Benningfield