Science Diction: The Origin Of The Word 'Comet' Although comets were sighted at least as early as 1000 B.C., Greek natural philosophers named them sometime around 500 B.C., using the Greek word kometes for "a head with long hair." Science historian Howard Markel discusses the word's origins and the study of comets through the centuries.

Science Diction: The Origin Of The Word 'Comet'

Science Diction: The Origin Of The Word 'Comet'

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Although comets were sighted at least as early as 1000 B.C., Greek natural philosophers named them sometime around 500 B.C., using the Greek word kometes for "a head with long hair." Science historian Howard Markel discusses the word's origins and the study of comets through the centuries.

Unidentified Man: The alphabet has only 26 letters. With these 26 magic symbols, however, millions of words are written every day.


And that music means it's time for Science Diction. This is our monthly feature where it - we come up with the origin of a word. And Howard Markel, professor of the history of medicine at the University of Michigan in Ann Arbor, he's also a director of the Center for the History of Medicine there - welcome.

Professor HOWARD MARKEL (University of Michigan): Hi, Ira. How are you?

FLATOW: Hi, there. What word do we have this month?

Prof. MARKEL: Well, look up in the sky, you might see one, Ira. It's comet.

FLATOW: All right. I look up in the sky here, I see clouds. But I'll take...

(Soundbite of laughter)

Prof. MARKEL: Here too with the Great Lakes...

FLATOW: Yeah. Comet, yeah. Where does that come from?

Prof. MARKEL: Well, they were cited long before they were named, probably as early as 1000 B.C. But around 500 B.C., some Greek natural philosophers named the word. They derived it from the Greek word for a head with long hair. It's kometes.


Prof. MARKEL: And that perfectly describes a wandering, bright, starry head followed by that long trail of misty hair-like light that we've all seen if we have been lucky enough to witness a comet.

FLATOW: Mm-hmm.

Prof. MARKEL: About a century later, Aristotle demoted comets. He said they are not stars at all but merely dry and warm exhalations from the Earth's lower atmosphere. And he was a very powerful scientist, so that held ground for almost until the 18th century. But for most of that time, many believed comets to be messages from the gods, harbingers or oracles of disaster and bad news.

FLATOW: Wow. So if you saw a comet, something bad was going to happen.

Prof. MARKEL: Yeah. For example, Plutarch recorded a comet that lit up the skies of Rome right around the time of Julius Caesar's assassination in 44 B.C. And about 1,700 years later, William Shakespeare repeated this warning sign in his play about Julius Caesar as well. Just before the birth of Christ, a comet was seen flying over Judea. And soothsayers told the king of Israel, Herod, that this presaged the birth of a boy who would someday outshine the monarch. And so, in response Herod ordered mass infanticide of all the boy - male children in Israel. That came to be known as the slaughter of the innocents.

And a lot of soldiers took it for granted too - Attila the Hun, Genghis Khan, and most famously, in 1066, King Harold II, he was king of England, saw a comet just before he was to fight the Battle of Hastings. And he lost, of course, to William the Conqueror and his band of Normans.

FLATOW: Yeah. That was recorded in a tapestry.

Prof. MARKEL: Yes.

FLATOW: Well, we're talking with Howard Markel on the origin of the word comet on SCIENCE FRIDAY from NPR. And so when did they finally sort out the real science on this?

Prof. MARKEL: Well, the science really came to pass when Edmund Halley -of course the most famous comet that we all know is Halley's Comet. He lived from 1656 to 1742. He was a prot�g� of Sir Isaac Newton. And Halley set out to disprove Aristotle by demonstrating that comets indeed traveled like planets in closed orbits around the sun. And he used various mathematical formulae, some concocted by Newton and some concocted by himself. And he showed that many - but certainly not all of the comet sightings across human history - represented a single astral phenomenon. And based on his calculations, he determined the periodicity of about 76 years.

And the last one that he saw - that he didn't see, but it was in 1682 -he predicted it would come back in 1758. And right on time, it appeared. And that ended the oracle sort of findings that other people had thought about.

FLATOW: So he didn't name his own comet.

Prof. MARKEL: No, no. He wrote a paper - in fact, he died before it actually came back. But, you know, they call the Halley's - I imagine that there's good news and bad news. Mr. Halley is dead, but we're naming a comet after you. So that's where Halley's Comet comes from.

(Soundbite of laughter)

FLATOW: Yeah. I hate it when that happens.

(Soundbite of laughter)

Prof. MARKEL: Yeah. Don't we all.

FLATOW: Yeah. In researching this stuff, did you come up with any favorite bit of comet history?

Prof. MARKEL: Oh, I did. And it concerns the life of Mark Twain, who's back on the best-seller list even though he's been dead for about 100 years. The night he was born, on November 30, 1835, there was a brilliant view of Halley's Comet flying right over his hometown of Florida, Missouri. And Twain remained fascinated by Halley's Comet for the rest of his life. And in 1909 he boldly bragged to his legions of readers: I came in with Halley's Comet in 1835; it's coming again next year in 1910, and I expect to go out with it. It would be a great disappointment in my life if I don't. The Almighty has said there are two unaccountable freaks: They came in together and they must go out together.

Well, like clockwork, Halley's Comet made its closest and most visible approach to the sun on April 20, 1910. And one day later, on April 21st, the creator of Huckleberry Finn died of a massive heart attack.

FLATOW: No kidding.

Prof. MARKEL: No kidding. Sometimes science can't explain everything, Ira.

(Soundbite of laughter)

Prof. MARKEL: That's weird.

FLATOW: So he predicted it himself. He'd come in with the comet and leave with the comet.

Prof. MARKEL: And he did, right on time.

FLATOW: Wow. You know, I'm trying to see what goes on in your brain, Howard. I mean, why of all the words did you settle on the word comet for this month?

Prof. MARKEL: Well, I was - tell you, I have a cup of - like many people, I'm a caffeine addict and I have a cup of coffee at a local shop called Comet Coffee in Ann Arbor. And I thought to myself, I don't know anything about comets, and you and your listening audience gave me a chance to find something out about it. And it's the great thing about looking things up. You never know what you're going to find, and it's almost always great.

FLATOW: Well, I have to send you out to do eclipse, because we have, you know, that lunar eclipse next month.

Prof. MARKEL: Yeah.

FLATOW: We'll have to send you on an assignment to look up the word eclipse.

Prof. MARKEL: Eclipse would be great, but you can't look at them, as I recall.

(Soundbite of laughter)

FLATOW: This one you can. A lunar eclipse...

Prof. MARKEL: Lunar you can. Right.

FLATOW: can look at, or we'll have to send you back to have another couple of cups of coffee, if that's where...

Prof. MARKEL: Well, I'm always more creative on a couple of cups of coffee, so...

(Soundbite of laughter)

FLATOW: All right. We want to you wish you a happy holiday.

Prof. MARKEL: And happy holiday to you and yours, Ira.

FLATOW: And we'll expect you back here next month, all right?

Prof. MARKEL: Okay. Great.

FLATOW: It's a date. And good luck to you. Howard Markel is professor of the history of medicine at the University of Michigan, Ann Arbor. He's also director of the Center for the History of Medicine there.

And that's about all the time we have for today. Greg Smith composed our theme music and with help today from NPR Librarian Kee Malesky. If you missed any part of our program, go over to our website. It's Download our podcast. You can go to our audio and video podcast. We have our Video Pick of the Week up there. It's about taxidermia. I think you're going to enjoy it.

You can also take us along, not only on your iPhone, but as of this week we have our Android app. Yup, you can go to the market and download our Android app and you can take along in your pocket our SCIENCE FRIDAY audio and our videos right there along with us. And we'll be back next week. It'll be Christmas Eve, but we'll be here. We'll hope to see you then.

I'm Ira Flatow, in New York.

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