Constellation
A constellation is a group of stars which make up imaginary outline or pattern in the night sky (the celestial sphere). Usually they are said to represent an animal, mythological person or creature in a shape. When seen, the group of stars seem to make a pattern.
The word constellation comes from Latin: con-, meaning together and stella- meaning stars. Some examples of constellations are Ursa major, Orion, Taurus, Draco, Cancer etc. Constellations were used to group stars. Different places in the world may have different constellations, but today astronomy has a fixed set of 88 constellations. This set is based on the Greek set and later some southern constellations were added, for example Antlia - the air pump. Most constellations have names that come from Greek mythology, like Orion or Andromeda.
There are 12 constellations in the Zodiac. The Sun travels through the Zodiac once each year. There is also a thirteenth constellation Ophiuchus - the carrier of a serpent, which the Sun goes through. However, most people do not think that it is in the Zodiac.
History
- No one knows who first saw the constellations. Ancient civilizations, like the Mayans, drew their own star maps of the skies with their constellations, very few of which we use today.
- Ptolemy's 48 constellations are still recognized by the IAU today, and the rest of the constellations were added later
Constellation Media
The Southern Cross in Crux and the 'Southern Pointers' of Centaurus can be used to find the southern pole star, Sigma Octantis.
Babylonian tablet recording Halley's Comet in 164 BC
Egyptian star chart and decanal clock, from the ceiling of Senenmut's tomb, c. 1473 BC
Chinese star map with a cylindrical projection (Su Song)
Sketch of the southern celestial sky by Portuguese astronomer João Faras (1 May 1500)
A celestial map from the Golden Age of Netherlandish cartography, by the Dutch cartographer Frederik de Wit
The Milky Way as seen from Earth, with prominent dark features labeled in white, as well as prominent star clouds labeled in black
Ottoman period celestial map, signs of the Zodiac and lunar mansions (Zubdat al-Tawarikh)
The Emu in the sky – a constellation defined by dark clouds rather than by stars. The head of the emu is the Coalsack with Crux directly above. Scorpius is to the left.
Inca dark cloud constellations in the Mayu (Celestial River), or the Milky Way; Crux is above Yutu, while the eyes of the Llama are Alpha and Beta Centauri.
