Tag Archives: etymology

A Harvest Tangent

 The other day someone mentioned the thirteen planets, and it gave me pause, since I thought there were less than when I was little, not more.

 

Oops. I didn’t realize all the dwarf planets had been named. Obviously I knew Pluto, and Eris sounded familiar, Ceres I thought was a large asteroid, and I didn’t remember Haumea or Makemake. I thought it was a good time of year to take a quick look at Ceres.

 

Ceres was the Roman goddess of agriculture, grain, fertility and motherhood. She’s essentially the Roman version of the Greek goddess Demeter. Linguists aren’t sure where the name Ceres comes from, one theory is that it shares a lost indo-European root with create, kernel, increase, corn, etc. We get the word cereal from her name.

 

 She was credited with discovering wheat (spelt) and with yoking oxen for plowing. Her main festival was held in spring, but now fall seems the appropriate time to visit the myths. The Romans saw her as connected to the line between life and death. She had a personal connection to the dead once the Romans nabbed Persephone from the Greeks and named her Proserpina.

 

In 1801 a newly discovered planet was named after her. It was first discovered on January 1, observed two dozen times, lost, then finally independently confirmed on December 31rst. (Perhaps Janus would have been a better name…) It has fluctuated between asteroid and planet and now seems to be considered both a dwarf planet and an asteroid.

 

Ceres is the only dwarf planet in the inner solar system. It lies in the asteroid belt between Mars and Jupiter. Even at its brightest it is too dim to see with the naked eye except in the darkest, clearest skies. When he first saw it, its discoverer wasn’t sure if it was a comet or planet, but it seemed to be too stable for a comet.

 

Ceres is about 600 miles in diameter, about the size of Texas.

 

 I wasn’t sure if the dwarf planet designation was all about size.

 

There seems to be a little more to it than that. Planet is a cultural and not a scientific designation, so the whole thing is sort of vague. The 2006 dwarf planet description is basically a spherical object in a more or less regular orbit around the sun that isn’t large enough for its gravity to have cleared its orbit of most other celestial bodies. (So too small to enlarge itself by eating all its neighbors.)

 

What’s cool is in March 2015 (scary how not far away that is) NASA’s Dawn mission will be studying the structure of Ceres and a nearby asteroid, Vesta, to see how they were formed. They think these small bodies have altered less in the past 4.6 billion years than the planets have, since Jupiter’s gravity both protects them and stopped them from forming a planet.

 

 

chemistry http://periodictable.com/Elements/058/index.html

Photograph of Cerium from Theo Gray’s wonderful book on the elements.

 The element cerium (58) was discovered in 1803, and named after the recently discovered planet.

 

It is the most common (and least expensive) of the rare earth elements. It’s nearly as common as copper, the rare earth elements are named less for their scarcity than for the trouble it takes to isolate them. Cerium is a soft silvery metal that can catch fire when it is struck. The whole piece won’t burn, but any bits knocked off burn as they’re made. So cerium is used in lighter flints and in special effects where lots of sparks are needed.

 

At high temperatures (65-80 degrees Celsius) it can ignite spontaneously in air. Its fumes are toxic and you can’t douse it with water since cerium will react with water ot product hydrogen gas. So as much fun as it sounds like to play with, it sounds like an element to avoid unless you have the training.

 

The Greeks sometimes call cerium dimitrio, after Demeter.

 

Okay, so it’s a dwarf planet and a rare earth element named after her second hand, but still not bad for a goddess mostly defunct for centuries!

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Dreidels and Chemistry

Honestly it’s only a one word connection, but it sticks for some reason.

 

So trivia for you: gadolinium (Gd, element 64) is the only element in the periodic table with a Hebrew etymology.

 

Gadol means great in Hebrew.

 

You see it in nes gadol haya sham meaning a great miracle happened there, this time of year. It’s a reference to the story of Chanukah, and dreidels have the first letter of each word on their sides. (Those same letters are also used to stand for whether you take or put into the pot when gambling with dreidels.)

 

Dreidel as a gambling game has roots in European history. Apparently it’s a riff off of an old Irish and English game called teetotum, and the terms for dreidel are Yiddish, a hybrid of Hebrew and German.

 

There’s some debate over whether the Hebrew letters on a dreidel (Nun, gumel, hei, shin) were there first in reference to the rules of the game and the Chanukah meaning added after, or if the game rules were tailored to fit the acronym celebrating Chanukah. I’ve seen arguments both ways and don’t have the background to make a call on it!

 

Gadolinium is one of the Lanthanides (f-block elements) naturally occurring rare earth metals. In nature it is only found in salt form. (Bonded to other elements.)

When separated it is a silver-white heavy metal. It’s useful in metallurgy since even a small amount improves the workability or iron alloys. It is also good at absorbing stray neutrons and so is used in radiography and nuclear reactors.

 

One of gadolinium’s main uses is in compounds for MRIs. Injected into the bloodstream, it will show where blood is and is not in a scan, which helps pinpoint the location of blocked or leaking blood vessels.

 

What’s really cool (and kind of mind bending, at least to me) is that it goes from being magnetic to not, depending on its temperature. This is called the Curie point, and in gadolinium it’s 19 degrees C (66 F). So if you use ice water to cool down gadolinium it will stick to a magnet, only to fall off once it warms up again.

 

It gets its name from the mineral gadolinite. A chemist studying gadolinite saw an unknown spectral band and identified an new element. (He actually had to use a different mineral with a larger gadolinium content to extract an oxide of gadolinium.)

 

Later a French chemist, P.E.F. LeCoq, separated metal from oxide and (since there’d already been a hullabaloo about his possibly naming his previous find after himself-he’s a piece of work, maybe we’ll talk about him later) he named this new element after the mineral in which it had first been identified.

 

This mineral had been named after Johan Gadolin. (b 1760)

 

Describing Gadolin as the everyman of the elements: “Gadolinium must stand as the memorial for all the chemists who have struggled to free a new element from its mineral source…” Hugh Aldersey-Williams, Periodic Tales.

 

Johan Gadolin was the chemist who discovered the first rare earth element- yttrium. (Well, first rare earth oxide, he knew it has a new element in 1794 but couldn’t extract it.) The mineral from which he isolated yttrium was named Gadolinite in his honor.

 

So the element was named after the mineral which was named after him for extracting a different element from said mineral. It’s kind of a nice naming circle!

 

Where does the Hebrew come in?

 

Clerical families often took a Latinized name. Instead of looking at Latin roots, Gadolin’s grandfather gentrified their family name by taking the Hebrew word for great and modifying it to fit with Latin forms.

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