We know our
world as the Earth. But is that its name?
planets of our solar system are all named for mythological beings.
Venus is the Roman goddess of love and beauty; Mars, the Roman god
of war; Jupiter the king of the Roman gods. But the Earth—what is
it named for? Dirt?
what about the moon? It, too, has fallen between the celestial
cracks. Other planets' satellites have been endowed with beautiful
names from mythology: Miranda, Titan, Ganymede, Charon. But our
moon is just, well, "the moon."
problem, when you get right down to it, is that our planet and its
natural satellite do not have official names. The explanation for
this dates back many centuries.
"During antiquity, people knew of five planets," explains E. N.
Genovese, Professor Emeritus of Classics and Humanities at San Diego
State University. "In the fourth century BCE, they called Jupiter
'Zeus-Star,' Saturn 'Chronos-Star,' Venus 'Aphrodite-Star,' Mercury
'Hermes-Star,' and Mars 'Ares-Star.'
“The moon was given the name 'Selene' in Greek,” he continued.
“It's just a generic name for something that shines, as is the Latin
'Luna.' Neither word has anything to do with divinities, but they
were later applied to divinities of those bodies. Then as mythology
developed—because there were two names—people made a separation and
lost touch with the original application of the name.
"The same goes for 'Earth.' The word is Germanic—the German word
for Earth is Erde. It's just a word for the ground or dirt,
and it got extended to something larger. Of course, when the word
was first derived, people had no sense of the Earth being one of the
planets. Once that was established, the name got transferred rather
This worked fine for
many centuries. Then, in March of 1781, musical composer and
amateur astronomer William Herschel found a new planet among the
stars of the constellation Gemini. In an attempt to get England’s
King George III on his side (and some money in his pocket for doing
astronomy), Herschel suggested naming the new world Georgium Sidus—“George’s
Star”—after the King. Fortunately, saner minds prevailed, and it
was eventually named “Uranus”—the Latinized form of “Ouranos”, the
Greek god of the heavens.
Strictly speaking, Uranus was the only Greek name among
the Roman planetary names. But since Uranus was the god of the
heavens, it seemed appropriate for the first planet found in modern
times. Later, when large
bodies were discovered in 1846 and 1930, scientists named them after
the Roman gods Neptune and Pluto.
Today, as astronomical discoveries mount at a record pace,
astronomers spend large amounts of time devising names. Charged
with this task is the Working Group for Planetary System
Nomenclatrure (WGPSN) of the International Astronomical Union (IAU).
try to follow a consistent theme," says Merton Davies of the Rand
Corporation, a former member of that group. "For instance, the
names of all except one of the original satellites of Uranus were
taken from Shakespeare. So when new satellites were discovered at
Uranus, we selected names from Shakespeare. At Neptune we use a
theme of water gods."
the IAU ever considered creating and approving a proper name for
our planet and its natural satellite—something to replace the
generic terms Earth and moon? "I suspect not," says Davies. "The
main reason is that the names work. They're within the literature,
and they're useful in communication. It would be a terrible chore
to try to change them."
Granted, there are more pressing problems facing us today. But
suppose we did want to name the Earth and the moon; what might we
come up with? Our first thought might be to call our planet Terra,
from which such words as "terrestrial" have sprung. After all, it
seems most natural. But it would not fit the scheme; Terra is not
the name of a god. More appropriate might be Tellus, the Roman
goddess of the earth, protector and developer of the sown seed. We,
then, would be named Tellurians.
moon has been known by many names over the ages: Artemis, Diana,
Phoebe, Cynthia, and Selene. Perhaps most fitting is Luna, Roman
goddess of the moon and the months. Future inhabitants of that
world might then be known as Lunarians.
present, of course, it's all academic. The Earth is the Earth and
the moon is the moon. And that suits some people just fine. "To
me, the most beautiful words are the simplest and the oldest," says
Charles Harrington Elster, author of the book There Is No Cow In
Moscow. "They're the most flexible and the most useful. The
fixed names of the planets that came from classical mythology are
quite lovely. But you'll never change Earth and moon."
Beautiful words, yes. Proper names, no.
while it's true that having no official name for our planet and its
natural satellite may not seem important now, it may become
necessary someday. Imagine the confusion in trying to draw up
treaties, diplomatic arrangements, and trade agreements with future
human colonists of other worlds without having an official name for
just wait until our first encounter with an extraterrestrial
being—one who has visited worlds throughout our galaxy. I'd love to
see the smirk on his little green face when we tell him our planet
doesn't have a name.
should it? It's the Earth!