Planets, Planets, Planets

October 13, 2017

Thanks to Alissa Simon, HMU Tutor, for today's post.

“The vastness of heavens stretches my imagination... Why do the poets of the present not speak of it? What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?” - Richard Feynman

In 1609, Johannes Kepler published a few surprising details. First, he said, “the orbits of the planets are ellipses with the sun at one focus.” Then he added, “the time it takes a planet to travel from one position in its orbit to another is proportional to the area swept out by a planet in that time.” This comes almost 70 years after Copernicus corrected Aristotle's view of the heavens. Aristotle's versions were so widely accepted that Copernicus's assertion that placed the sun in the center of the universe upset many people. Kepler, too, shocked with his description of elliptical orbits around the sun. It was not until Newton arrived on the scene that these theories were put to scientific tests. In fact, Newton explained a lot about the celestial beings in his laws of motion. While Newton used calculus to support his scientific findings, he realized that he had to explain the motions in terms that other scientists in his day might understand. Therefore, he proved the motions of the planets using plane geometry. (“Just for fun”, Richard Feynman proved the same in his “lost lecture”, which can be found here: )

Aristotle believed in natural final forms. In his book Meteorology, he explains his hierarchical system which includes: fire, air, water, earth. What may sound trivial to us is incredibly complicated, however. Aristotle observed a great number of events – some of them celestial – and attempted to explain them or their origins within his working framework. Yet even Aristotle understood that his categorization was incomplete. He admits the limits of scientific language in explaining his theories. He argues for a more scientific understanding of the processes on earth. He writes, “Some say that what is called air, when it is in motion and flows, is wind, and that this same air when it condenses again becomes cloud and water, implying that nature of wind and water is the same. So they define wind as a motion of the air. Hence some, wishing to say a clever thing, assert that all the winds are one wind, because the air that moves is in fact all of it one and the same; they maintain that the winds appear to differ owing to the region from which the air may happen to flow on each occasion, but really do not differ at all. This is just like thinking that all rivers are one and the same river, and the ordinary unscientific view is better than a scientific theory like this. If all rivers flow from one source, and the same is true in the case of the winds, there might be some truth in this theory; but if it is no more true in the one case than in the other, this ingenious idea is plainly false. What requires investigation is this: the nature of wind and how it originates, its efficient cause and whence they derive their source; whether one ought to think of the wind as issuing from a sort of vessel and flowing until the vessel is empty, as if let out of a wineskin, or, as painters represent the winds, as drawing their source from themselves.” Science often requires metaphor, and Aristotle certainly used this linguistic device. Drawing upon the idea of vessels being filled or emptied or the idea of a wineskin helps others understand his theory. It also helps to explain when there is no language for explanation. At times he writes of “stuff” or ambiguous “forms” and explains that we must use this terminology because it is what we have to use.

Creating a language for something new requires thought and metaphor. Proper nouns often rely upon metaphor or story. This is especially true of celestial beings. When Uranus was discovered in 1781, there was no standard of naming. It wasn't until 1850 that Uranus was officially accepted and a process for naming celestial beings was established. The International Astronomical Union (IAU), founded in 1919, now controls all names. Assuming that all planets within our solar system have been identified, they deal mostly with moons, surface features, asteroids, and comets.

Photo credit: Alissa Simon

Photo credit: Alissa Simon

Mercury, Venus, Mars, Jupiter and Saturn have been recognized in the heavens throughout history. The next three planets were identified as technology advanced. First Uranus in 1781, then Neptune in 1846 and, if you want to include it, Pluto in 1930. Early cultures identified the movement of the planets with the movement of mythological beings. For this reason, Romans named Venus after the goddess of love, who would surely be epitomized by the brightest and most beautiful celestial being. Mars, of course, the god of War, takes on a reddish appearance, and Mercury whose orbit is so short, moves swiftly on winged feet. Merriam-Webster tells us that Earth, ironically, comes from the Indo-European base 'er,'which produced the Germanic noun 'ertho,' and ultimately German 'erde,' Dutch 'aarde,' Scandinavian 'jord,' and English 'earth.' Related forms include Greek 'eraze,' meaning 'on the ground,' and Welsh 'erw,' meaning 'a piece of land.' Jupiter, the largest and most massive of the planets was named Zeus by the Greeks and Jupiter by the Romans. This name depends entirely upon size because he was the most important deity in both pantheons. Saturn (Cronos in Greek) was the father of Zeus/Jupiter. Since it is visible by the naked eye, Saturn has a variety of names from other cultures as well. (Find a wonderful list of names gathered from many cultures here: ). Uranus was first seen in 1781 as noted above, named for the father of Cronos/Saturn. Neptune followed in 1846 and is named for the Roman god of the sea. Pluto is named after the Roman god of the underworld. The name especially fits this body because Pluto can make himself invisible at will, as does Pluto in its orbit.

As science continues to push to exoplanets and quantum physics, language will continue to evolve. As technology jumps from email to iPhones to cloud computing, we continue to see metaphors emerge and converge, proving that language must evolve simultaneously with culture.

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