Human ignorance, sadly, isn't limited to planet Earth. Even today, over 400 years after the Age of Enlightenment began, plenty of people are still getting plenty of stuff wrong--not just about our home planet, but about the whole universe. Luckily, Jeopardy!s Ken Jennings is the author of a new book about the mysteries of the cosmos, the Junior Genius Guide to Outer Space. In this month's Debunker columns, he'll set us straight on a whole sky full of starry slip-ups. These are some misconceptions of truly astronomical proportion.
The Debunker: Star Myth #3: Are There Twelve Constellations in the Zodiac?
Little-known fact: the relative positions of celestial bodies millions or hundreds of millions of miles from Earth do not, in fact, affect your mood, character, and luck on a day-to-day basis, despite what syndicated newspaper columns would have you believe. But the signs of the Zodiac are not just accidental, arbitrary superstitions. Astronomy and astrology are very different fields, but they share the same roots: man's earliest observations of the stars.
As we saw two weeks ago astronomers divide the night sky into regions called constellations. Anciently, there were twelve of these constellations that lay along the ecliptic, the plane of our solar system. From our vantage point, the Sun, Moon, and other planets always lie on or very close to the ecliptic. The classic western Zodiac is a division of the year into twelve equal "signs," roughly corresponding to the constellations through which the Sun passes throughout the year. The position of the Sun relative to the Zodiac on a given day is what determines one's "sign."
But here's the problem: the list of constellations was standardized by astronomers in 1922, and the modern roll call is a little different from what the ancients believed. Among other things, in our new layout, the ecliptic now passes through a little-known thirteenth constellation between Scorpio and Sagittarius. Who is this interloper? Ophiuchus, the "serpent-bearer." Ophiuchus doesn't affect most astrological systems, which pre-date 1922 and are based on a twelve-sign Zodiac. But in astronomical terms, Ophiuchus is the correct sign of the Zodiac during most of every December. Don't care about scientific accuracy when it comes to your horoscope? Ugh, you are such an Aquarius.
Quick Quiz: Which is the only sign of the Zodiac named for an inanimate object?
Ken Jennings is the author of six books, most recently his Junior Genius Guides, Because I Said So!, and Maphead. He's also the proud owner of an underwhelming Bag o' Crap. Follow him at ken-jennings.com or on Twitter as @KenJennings.