How the Planets in Our Solar System Got Their Names
Rujuta Patil
The planets in our solar system are no less than a family! They have been named after Greek and Roman deities. This post talks about how these nine astronomical entities got their names.
Organized by IAU and Zooniverse, it is the first opportunity for the public to name a list of 20 most popular ExoWorlds (exoplanets).
NameExoWorlds Contest
The International Astronomical Union (IAU) is the internationally recognized authority that is responsible for naming all celestial bodies in this universe.
Established in the year 1919, the IAU works to promote and safeguard the science of astronomy in all its aspects, through international cooperation.
A planet, according to IAU, is a celestial body that (a) is in orbit around the Sun...
...(b) has sufficient mass for its self-gravity to overcome rigid body forces, so that it assumes a hydrostatic equilibrium (nearly round) shape
(c) has cleared the neighborhood around its orbit.
How the Planets Got their Names
Mercury, Venus, Mars, Jupiter and Saturn were named thousands of year ago. the rest were not discovered until a few hundred years back.
The IAU recognises and thus carries forward the tradition of naming the planets after Roman and Greek deities.
The IAU Working Group for Planetary System Nomenclature (WGPSN) is the body that finalizes and assigns names to any newly discovered celestial body or the features on their surface.
As kids, we must have found these nine names difficult to remember. It is only with some trick that we succeeded in memorizing them; of course, better if they are memorized in the correct order.
All planets except Earth are named similarly. A common thread is their association to Greek or Roman mythology. Pluto is not considered a planet now, but since it was earlier, and has some history to its name, it is included here.
Mercury
We cannot forget this little celestial body which is closest to the Sun. The Romans named this planet 'Mercurius', because its movement in the sky appears very quick and swift.
It is also identified as the Messenger of the Gods (or of Jupiter). Known as 'Hermes' in Greek mythology, it refers to the god of commerce, theft, cunning, and invention.
Venus
If you have ever gone out for star gazing, this is one of the first identifiable objects in sky. Venus is beautiful, prominent, and the brightest amongst all.
The term 'Venus' represents the Roman Goddess of Love and Beauty. Also, it is known as the counterpart of the Greek Goddess Aphrodite.
Interesting fact: Until it was evident that both are the same object, this planet was called 'Lucifer' as a morning star, and known by the name 'Venus' as an evening star.
Earth
This is no Roman goddess representing life, or any other emotion. In fact, as you might have noticed, many languages use similar terms for denoting Earth.
The term stems from the Indo-European base of 'er', which formed the German noun 'ertho'. In German language, the Earth is known as 'Erde', in Dutch 'Aarde', in Scandinavian 'Jord', and in English it is 'Earth'.
Mars
The red color of this planet is the reason behind its name. The Romans named it their God of War due to its blood-like appearance. He was also the father of Romulus and Remus.
Ares is his Greek counterpart. In other civilizations too, its peculiar red color has created its names; 'Her Desher' is the name for Mars in Egypt, which means the 'the red one'.
Jupiter
In Roman culture, Jupiter symbolizes the King of Gods. As the largest planet in our solar system, it's fittingly named after this mighty deity.
This planet is called 'Zeus' by the Greeks. With the symbols of a lightening bolt and an eagle, Jupiter was the most significant deity for these civilizations.
Saturn
The Roman God of Agriculture, shares his name with the ringed planet. In mythology, he's Zeus (Jupiter), Neptune, and Pluto's father, with his name interpreted from the Greek Kronos.
Uranus
It was discovered in 1781 by William Herschel, who had earlier named the planet 'Georgian Sidus' after George III.
Later that year, Johann Bode named it 'Uranus', or God of the Sky, or the Heavens for the Greeks. Also, as per Greek mythos, Kronos is the son of Uranus, and Jupiter is the grandson of Uranus.
Neptune
Discovered in 1846 by Johann Gottfried Galle based on Urbain Le Verrier's predictions, Neptune's striking blue hue was prompted by perturbations in Uranus's orbit.
Initially, Galle wished to name it after Le Verrier, but the international astronomical community did not agree. So, it was named after Roman God of Sea. Poseidon is the Greek deity same as the Roman sea god.
Pluto
Since the 2006 IAU resolution defining planets, Pluto has been excluded from the list of nine. Discovered by Clyde Tombaugh in 1930, it's now classified as a dwarf planet.
It is named after the Roman God of the Underworld. It also exemplifies the eternal darkness that is associated with its distant location.