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Moon and Zubenelgenubi
World War II ended 76 years ago. We can’t go back in time to see it happen. But we can see something from that same time: the light from the southern claw of the scorpion.
The claw is represented by the star Zubenelgenubi. It’s just a whisker below the Moon this evening — so close that it may be a bit difficult to see through the Moon’s glare. The star is in the constellation Libra, the balance scales. But its name comes from a time when it represented the southern claw of Scorpius, which is next door.
The system consists of at least four stars, which are split into two pairs. One pair is about 75 light-years from Earth, while the other is about a light-year farther.
A light-year is the distance light travels in one year — almost six million million miles. If a star is 76 light-years away, that means its light has taken 76 years to reach us. Put another way, the light we see from it tonight actually left the star 76 years ago — which is the case with one half of the southern claw of the scorpion. So we don’t know what’s going on with the star right now — and won’t until around the year 2097.
Of course, the reverse is true as well. If any of the stars of Zubenelgenubi have planets, and if there’s anyone on those planets who’s looking toward the Sun, they’ll see it as it looked 76 years ago — at the time a global conflict was ending on the Sun’s third planet.
Script by Damond Benningfield