From Alcor to Zappafrank: How the stars and other celestial objects got their names
Updated 1750 GMT (0150 HKT) May 26, 2021
(CNN)If you step out the door on a clear, dark night at this time of year, you'll find the great constellation called Ursa Major high in the sky below Polaris, the pole star.
You might even be able to pick out a small star there, in the middle of the handle of the Big Dipper. It's called Alcor, a binary star paired with the nearby, brighter Mizar, Arabic for "cloak." In Arabic, the former star is called al-Khawwar, "the faint one," and finding it made for a good eye test in the days before wall charts.
"He can see Alcor," an Arabic proverb has it, "but not the full moon," akin to not being able to see the forest for the trees.
Arabic, Latin, English: three languages appear side by side in that one constellation, the third largest of the 88 constellations in the night sky. Along with them are Greek characters and an alphabet soup of letters and numbers employed by a variety of star catalogs.
Alcor has so many names -- 80 Ursae Majoris, g Ursae Majoris, HD 116842, GC 18155, HIP 65477, SAO 28751, PPM 34021 -- and the list goes onto 80 UMa Ca, the designation approved by the International Astronomical Union, the ultimate arbiter of such things.
There are countless objects up there in the sky: planets, stars, comets, constellations, moons. And for every one of the ones we can see with our eyes or with powerful telescopes, there's a name that some Earthling has given it. Those names number in the millions and come from many languages. Just as astronomers and space scientists have their favorites among all these celestial bodies, they have their favorite names as well.
A constellation of languages
Arabic is so prominent in the names of the stars because Arabic scholars preserved and studied thousands of Greek and Latin manuscripts lost to Europe during the Dark Ages. So it is that the brightest star in Orion, the constellation named for a Greek demigod, is called Betelgeuse, "the arm of the giant." Its companion is called Rigel, Arabic for "foot." Elsewhere, the brightest star in the zodiacal constellation Taurus is called Aldebaran, whose Arabic name is thought to mean "following behind," since it appears to tag along with the movements of the Pleiades.
"My favorite star names are Zubenelgenubi and Zubeneshamali, the two brightest stars in the constellation Libra," said astrophysicist and science ambassador Neil DeGrasse Tyson, host of the entertaining "StarTalk" science podcast.
"I was intrigued by their names from childhood—long before I learned of their Arabic origins and the seminal contributions of Arabic scholars to astronomy, navigation and other fields," he said. "The names translate to Southern and Northern Claw of the scorpion, back when parts of Libra were considered parts of a more floridly illustrated Scorpio."
By long historical convention, constellations and star groups known to the Greeks and Romans bear Greek and Latin names, as do all the planets in our solar system save ours. Many of those names come from mythology. For instance, those Pleiades—a star cluster also known as Messier 45, honoring an 18th-century French astronomer, and located above Aldebaran—take their name from seven sisters whom Zeus turned into stars. In Japanese, incidentally, the Pleiades are known as Subaru, from which the automobile company takes its name.
Some classical names refer to location or appearance. Our Milky Way comes from Greek by way of Latin; the ancient Via Galactica, or "road of milk," for that huge band of white stars, also gives us our word "galaxy." Sirius, the brightest star in the heavens, takes its name from the Greek word for "scorching," since it dominates the sky in the "dog days" of summer, while its neighbor Procyon rises a little earlier than the so-called Dog Star, its name meaning "before the dog." And Polaris is so called because it stands above what geographers call geodetic north, the "true North Pole." It will earn its name until some other object takes its place as the pole star, stella polaris, centuries from now.
Latin is everywhere in the sky, commemorating not just ancient Roman science but also the fact that Latin was the international language of learning for many centuries. By another convention, all the zodiacal constellations bear Latin names, while names such as our "Sea of Tranquility," where the Apollo 11 Eagle lander touched down under the sure hands of Neil Armstrong and Buzz Aldrin, is a direct translation of the Latin "Mare Tranquillitatis."<