Astrological sign of the times

The entire universe in blog form
Jan. 13 2011 1:21 PM

Astrological sign of the times

Sometimes, I'm not even sure where to begin with something.

OK. So this afternoon I see on Twitter that the word "zodiac" is trending, meaning lots of people are talking about it (as I write this it still is). Right, that happens sometimes, and sometimes I'll post a snarky response. But I also see the word "Ophiuchus" trending, and I think, what?

Phil Plait Phil Plait

Phil Plait writes Slate’s Bad Astronomy blog and is an astronomer, public speaker, science evangelizer, and author of Death from the Skies!  


Then I get an email from BABloggee Kevin Jung saying he heard some DJs on a radio program talking about how astronomers have "rearranged the zodiac". Even before I read another sentence I pretty much know what's going on. Happily, Kevin found the source of all this: an article in Minnesota's Star Tribune. And it all falls into place.

OK, first, let's get this out of the way:

Got it? Good.

Great, so what's with this new story? Basically, the Star Tribune talked to an astronomer and an astronomy teacher in the area, who (correctly) poo-pooed astrology. The astronomer mentioned that the signs of the zodiac have shifted since they were first invented thousands of years ago. This is true, because the Earth's axis wobbles over time, which has the effect of shifting the positions of the zodiacal constellations in the sky, or, more accurately, the time of the year the Sun passes through them. So it used to be that if you were born on March 22, you were an Aries... if you went by the original timing of when the Sun was in Aries. But now, millennia later, the Sun is actually in Pisces on that date. And it won't be much longer before it's in Aquarius in late March (hence "the dawning of the Age of Aquarius", in case you're my age and a hippy or a 5th Dimension fan).

So that takes care of the shifting zodiac constellations bit. What about Ophiuchus?

Ophiuchus (which I pronounce oh-FYE-uh-cuss) is the serpent bearer, and is a constellation near Scorpius in the sky. Technically, the Sun passes through Ophiuchus, and in fact is in the constellation longer than it's in Scorpius! But we don't include it in the zodiac for a couple of reasons; one is that the stars in it are pretty faint, while those of Scorpius are brighter and easier to recognize, and another is that we can't have 13 constellations, can we? So poor Ophiuchus is sent off to hold his serpent by himself.

That's really all there is to it. The constellations aren't being redefined, and certainly not suddenly by some astronomical coup (the same group, no doubt, being blamed for Pluto). And Ophiuchus has long been a point of contention. Nothing in this story is new at all! It's another case of media (social or otherwise) fueled nonsense.

I'll note this silliness has extended well beyond Twitter; the prestigious scientific journal OK!* says that "Taylor Swift’s the New 13th Sign Ophiuchus!" and goes on to say that even if the astrological signs change, "horoscope readings reportedly shouldn’t be affected."

Phew! I'll agree with them on that. After all...

* Not an actual scientific journal.

Related posts: