.Enjoy our starry night skies
Be a considerate neighbor: reduce nighttime glare.
Shield your outside lights downward.
Let the stars light up the night.
March 2012 Night Sky
Sky Full of Gods:
Elementary school children memorize these, in order, in science classes. Astrologists chart them. Astronomers follow them. And, columnists write about them every month: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Neptune, Uranus, and yes, Pluto. Then there are Deimos, Ananke, Tarvos, Caliban, Larissa, Charon, Dysnomia. Oh, and to make the list complete, Luna (Latin for ‘Moon’). These are all names of moons orbiting planets and dwarf planets in our solar system. Just how and where do these objects get their names?
The answer is the International Astronomical Union, founded in 1919 with the purpose of promoting and safeguarding the science of astronomy through international cooperation. Among its various tasks is to define an unambiguous astronomical nomenclature, which includes naming various objects in the night sky. The names for the planets seem like an easy task since the brighter, closer planets have been named from antiquity. Unfortunately, each culture has its own set of names. Officially, the IAU has set rules for naming planets and other celestial objects.
Mercury has been recognized since the third century BC, but the Sumerians then thought the morning and evening appearances represented two different objects. The Greeks did understand the two appearances were a result of one object. The official name comes from Roman mythology. Mercury was the Roman god of commerce, travel, and thievery.
Periodically being the brightest thing in the night sky after the moon, Venus was known in prehistoric times. Like Mercury, some cultures thought it was two different objects: Lucifer or Eosphorus in the morning and Hesperus in the evening. Venus is the Roman goddess of love. The Greek goddess was Aphrodite, in Babylonia she was Ishtar. For the most part, the features on Venus are named after female figures.
The only exception to the naming of planets after Roman and Greek gods is Earth. The English name originates from Germanic ‘ertho’, German ‘erde’, Dutch ‘aarde’ and ultimately English ‘earth.’
Mars, also known since prehistoric times, has been the subject in many science fiction stories. Though smaller than Earth, it is seen as a possible place for aliens and, eventually, earthlings to live. Known as the “Red Planet,” Mars is named for the Roman god of War (Ares in Greek). And, the name of the month March is derived from Mars. One moon, Phobos, orbits just 3,700 miles over the surface of Mars. Phobos is one of the sons of Ares. Another son of Ares, Deimos, also orbits Mars.
The largest, and the fourth brightest object in the night sky, is Jupiter, named for the king of the Roman gods who ruled on mount Olympus. In 1610, Galileo pointed his telescope at the bright point of light in the sky and discovered Jupiter’s four large moons: Io, Europa, Ganymede and Callisto. Jupiter’s satellites are named after characters associated with Zeus (the Greek equivalent of Jupiter), many were lovers.
Saturn confused Galileo with its shape when he observed it in 1610. It was not until 1659 that Huygens inferred the planet had rings around it. The sixth planet from the Sun is named for the Roman god of agriculture (Cronus from Greek mythology). Saturn is the son of Uranus and gives us the root of the word ‘Saturday’. Some of its satellites were named after the Greek Titans who were brothers and sisters of Saturn. The more recent satellites are being named for Gallic, Norse, and Inuit mythical giants.
The Greek god of the sky gives his name to Uranus (officially pronounced ”your-ah-ness”). This planet is a recent discovery, found by William Herschel in 1781. He originally named it “Georgium Sidus” (the Georgian Planet) to honor King George III. Uranus was suggested to conform to the naming of the other planets and the name finally stuck in the 1850s. Departing from mythological references, Uranus’ moons are named for characters from Shakespeare and Pope stories.
The last of the official planets is Neptune named for the god of the sea (Poseidon in Greek). Neptune was first observed by Galle and d’Arrest in 1846. Irregularities in Uranus‘ orbit did not match theory. It was speculated another unknown planet was the cause. After a search, Neptune was found. The moons of this planet are named after sea nymphs and other figures associated with the sea.
Until its demotion, Pluto was a planet named after the Roman god of the underworld and its moon, Charon, was named for the boatman who ferried souls across the river for Pluto’s judgment.
The dwarf planets are Ceres, the Roman goddess of agriculture; Eris, the Greek goddess of strife and discord; Makemake, the Easter Island creator of humanity and god of fertility; and Haumea, the matron goddess of the island of Hawaii.
So, our Solar System is filled with deities, but as of yet, there are no conventions or rules for naming exoplanets.
The Planets and Moon:
- Look for Mercury low in the west after sunset the first of the month.
- Venus is very bright in the southwest after sunset. Look on the 13th two hours after sunset to see Venus and Jupiter at their closest approach. The Moon-Venus conjunction occurs on the 26th.
- Mars can be seen low in the east after sunset. Mars reaches opposition on the 3rd, the opposite direction from the Sun as seen from Earth.
- Jupiter is also very bright in the evening sky above Venus. There is a Moon-Jupiter conjunction on the 25th.
- Saturn rises in the east about an hour and a half after sunset.
- The Moon is full at 2:40 a.m. on the 8th and new at 8:37 a.m. on the 22nd.
- • Spring begins at 11:14 p.m. on the 19th and Daylight Savings Time starts on the 11th.