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Notes on video lecture:
Naming Moons
Choose from these words to fill the blanks below:
sylph, Oceanus, Pluto, Phobos, ivory, Huegens, Hershel, Lassell, cow, Desdemona, Jupiter, Union, Ganymede, Hercules, Sicily, lovers, permanent, Hades, umbra, Minos, Artemis, nymph, Marius, Arcas, mythological, Gaia, Galileo, 1610, dog, provisional, castrated, Fenrir, Shakespeare, Tityos, Roman, 1919
the right to name moons and features on their surfaces belongs to a body known as the International Astronomical            (IAU)
founded in         
if you find a new moon, you suggest a name to the IAU but they don't have to accept it
today, when a moon is discovered
it is given a                        name, e.g. S/2005 P1
S = Satellite
2005 = year of discovery
P = primary body, in this case, Pluto
1 = first moon of            discovered that year
later when the discovery has been confirmed, the IAU gives it an official,                    name
in this case, S/2005 P1 became Hydra
named after the snake-headed monster killed by                 
but why Hydra
when a new moon is discovered, it is given a name that fits in with the theme for names that have already been chosen for moons of that planet
moons of Pluto are named after figures with a connection to           
               started this tradition
when he discovered the first four moons of               , there were no rules about naming moons
he used            numerals, so we had Jupiter I, Jupiter II, etc.
Simon             , a rival of Galileo
proposed a                          theme
since the planet was named after the Roman god Jupiter, or Zeus, why not name the moons after the              of Zeus
discovered in         
mortal lover of Zeus
ancestor of Hercules
Hera turned her into a       
mother of King            of Crete
abducted by Zeus in the form of a white bull
mentioned in Iliad
homeland was Troy
son of Tros
abducted by Zeus in the form of an eagle
Homer describes him as the most beautiful of mortals
daughter of Lycaon, king of Arcadia
took a vow to remain a virgin
to have sex with her, Zeus disguised himself as                (Diana) herself, in order to lure her into his embrace
Callisto was discovered pregnant and was then turned into a bear
gave birth to a son called           
Zeus placed them both in the sky as the constellations Ursa Major, called Arktos [αρκτος], the "Bear" and Ursa Minor.
16 newer moons are named after other relations with Zeus, e.g.
1892 Amalthea
the most-frequently mentioned foster-mother of Zeus
located in Crete
1904 Himalia
a            of the eastern end of the island of Rhodes, Zeus was enamoured with her and she produced three sons with him
1905 Elara
Zeus fell in love with Elara and hid her from his wife Hera's jealousy by placing her deep beneath the Earth. This was where she gave birth to             , a giant who is sometimes said to be the son of Gaia, the Earth goddess, for this reason. It is further added that Elara died in labour because of the enormous size of her baby
1974 Leda
admired by Zeus, who seduced her in the guise of a swan
moons of Saturn
five largest moons were discovered by Christian                (1629-1695)
and Giovanni Domenico Cassini (1625-1712)
Huegens followed Galileo's conventions and gave the moons numbers rather than names
when Sir William Hershel (1738-1822) discovered two other moons of Saturn
also declined to name them
his son, Sir John               , settled the matter
since Saturn was the Greek equivalent of Cronos, the leader of the Titans, Sir John named the largest moon Titan
the other moons were named after other Titans
son of Uranus and         
father of Atlas, Prometheus, Epimetheus and Menoetius.
daughter of Uranus and Gaia
wife of her brother the Titan-god               
daughter of Okeanos and Tethys, hence an Oceanid, a water-nymph. She is otherwise called a daughter of Gaia
daughter of the earth goddess Gaia and the sky god Uranus, and sister and wife to Cronus
the two innermost moons were named after the Titan's half brothers, two giants
Mimas was one of the Giants, the offspring of Gaia, born from the blood of the                    Uranus
one of the Giants, the offspring of Gaia (Earth), and Uranus (Sky). Enceladus was the traditional opponent of Athena during the Gigantomachy, the war between the Giants and the gods, and was said to be buried under Mount Etna in             
the pace of discovers meant that astronomers were running out of Greek and Roman names
so gods from other cultures are used
named after monstrous Norse wolf Fenrisulfr
Sir John Hershel
also discovered moons of Uranus, the planet discovered by his father
Uranus is the god of the air
took his inspiration from English literature
Oberon (1787)
Oberon, the king of the fairies in                       's A Midsummer Night's Dream.
Titania (1787)
Titania, the queen of the fairies in Shakespeare's A Midsummer Night's Dream
named after the leading            in The Rape of the Lock
also the name of the spirit who serves Prospero in Shakespeare's The Tempest
Umbriel is the "dusky melancholy sprite" in Alexander Pope's The Rape of the Lock, and the name suggests the Latin           , meaning shadow
as more moons were discovered, they were named after characters in Shakespeare's plays
moon of Uranus
named after the daughter of Polonius in Hamlet
King Lear
Much Ado About Nothing
Neptune's first moon
discovered by William                (1799-1880) but he had nothing to do with naming it
naming duties fell to the French astronomer Camille Flammarion
carried on with the mythical theme
Neptune's moon was named Triton, the Greek sea god Triton [Τρίτων], the son of Poseidon (Neptune)
second moon
named after the Nereids, sea-nymphs of Greek mythology and attendants of the god Poseidon
later moons were also named after water spirits
a nymph from Thessaly
an early sea-god or god of rivers and oceanic bodies of water, one of several deities whom Homer calls the "Old Man of the Sea"
Galatea [Γαλάτεια]
"she who is milk-white"
the statue carved of            by Pygmalion of Cyprus, which then came to life
1887 tiny moons
Deimos ("terror")
Phobos (panic/fear) and Deimos (terror/dread) accompanied their father Ares, god of war, into battle
dwarf planets
Pluto, the god of the underworld
moons are related to Hades
Charon [KAIR-on]
the boatman who ferried the dead across the river Styx
the many-headed       
the snake-headed monster


Simon Marius (1573-1625)
German astronomer who claimed to have discovered four major moons of Jupiter some days before Galileo Galilei
  • Galileo accused Marius of plagiarism
  • a jury in The Netherlands in 2003 examined the evidence extensively and ruled in favor of Marius
  • while Galileo named the moons Jupiter I, Jupiter II, Jupiter III, and Jupiter IV, Marius named them after the lovers of Zeus, i.e. Io, Europa, Ganymede, and Callisto
  • drew conclusions about the structure of the universe from his observations of the Jovian moons and the
  • concluded from his observations of the Jovian moons that they must orbit Jupiter while Jupiter orbits the Sun
  • Marius concluded that the geocentric Tychonic system, in which the planets circle the Sun while the Sun circles the Earth, must be the correct world system, or model of the universe
  • spent most of his life in the city of Ansbach
Christiaan Huygens (1629-1695)
Leading Dutch mathematician and scientist of his time whose work included early telescopic studies of the rings of Saturn and the discovery of its moon Titan, and the invention of the pendulum clock
  • mathematical tutor Jan Jansz de Jonge Stampioen set the 15-year-old a demanding reading list on contemporary science
  • studied law and mathematics at the University of Leiden from 1645 to 1647
  • generally wrote in French or Latin
  • in 1655, Huygens proposed that Saturn was surrounded by a solid ring, "a thin, flat ring, nowhere touching, and inclined to the ecliptic"
  • in the same year, he observed and sketched the Orion Nebul, his drawing, the first such known of the Orion nebula
  • 1659, Huygens was the first to observe a surface feature on another planet, Syrtis Major, a volcanic plain on Mars
  • shortly before his death in 1695, Huygens completed Cosmotheoros, published posthumously in 1698, in which he speculated on the existence of extraterrestrial life on other planets which he imagined was similar to that on Earth
  • he argued that extraterrestrial life is neither confirmed nor denied by the Bible, and questioned why God would create the other planets if they were not to serve a greater purpose than that of being admired from Earth
  • Huygens postulated that the great distance between the planets signified that God had not intended for beings on one to know about the beings on the others, and had not foreseen how much humans would advance in scientific knowledge

Spelling Corrections:


Ideas and Concepts:

Learned via this morning's Moons of the Solar System class:

"The International Astronomical Union frequently receives requests from individuals who want to buy stars or name stars after other persons. Some commercial enterprises purport to offer such services for a fee. However, such names have no formal or official validity whatsoever. Similar rules on buying names apply to star clusters and galaxies as well. For bodies in the Solar System, special procedures for assigning official names apply, but in no case are commercial transactions involved.

Thus, like true love and many other of the best things in human life, the beauty of the night sky is not for sale, but is free for all to enjoy. True, the gift of a star may open someone's eyes to the beauty of the night sky. This is indeed a worthy goal, but it does not justify deceiving people into believing that real star names can be bought like any other commodity."
Greek mythology and the moons of Pluto via this evening's Moons of the Solar System class:

"When a new moon is discovered in our Solar System, it is given a name that fits with the theme for names that have already been chosen for moons of that planet. Since Pluto is the Roman god of the underworld which corresponds to the Greek god Hades, it's first moon discovered in 1978 had to follow this theme.

The first moon Charon, discovered in 1978, was originally going to be called Persephone, an appropriate name as she is the wife of Hades after being abducted by him and taken to the underworld. But the wife of the man who discovered this moon, James Christy, was named Charlene and so Christy wanted to name the moon after her, and so settled on the similar sounding name Charon, the ferryman of Hades who carries souls of the newly deceased across the rivers Styx and Acheron that divided the world of the living from the world of the dead.

Pluto's second moon, Hydra, discovered in 2005, was named after the many-headed serpentine water monster living in the the lake of Lerna, an entrance to the Hades' underworld. In the canonical Hydra myth, the monster is killed by Heracles, using sword and fire, as the second of his Twelve Labors.

The third moon, Nix, discovered in 2005 with Hydra, was named after the goddess of the night, Nyx, a shadowy figure who, at the beginning of creation, mothered other personified deities such as Hypnos (Sleep) and Thanatos (Death), with Erebus (Darkness). Her appearances are sparse in surviving mythology, but reveal her as a figure of such exceptional power and beauty that she is feared by Zeus himself. The moon's name is spelled Nix to avoid confusion with the Mars-crosser asteroid 3908 Nyx.

In 2011, the fourth moon, Kerberos was discovered, and named after Cerberus, or the Hound of Hades, the monstrous multi-headed dog that guards the gates of the Underworld to prevent the dead from leaving. The moon's name is spelled Kerberos so that it is not confused with the near-Earth asteroid, 1865 Cerberus.

In 2012, the moon Styx was discovered, which is of course named after Styx, the river that forms the boundary between Earth and the Underworld and together with the rivers Phlegethon (Dante's "river of blood"), Acheron (river of woe), Lethe (river of forgetfulness), and Cocytus (John Milton's "rueful stream") which all converge in a great marsh at the center of the Underworld."
What is a Moon?
The Icy Moons
Naming Moons