- Constellations are star patterns in the night sky
Constellations are groups of stars that have been imaginatively linked together to depict mythological characters, animals and objects from mankind’s past. They can also be used to predict the seasons for farming, measuring time or as a directional compass.
- There are 88 official Constellations
In 1922, the International Astronomical Union (IAU) officially recognized 88 constellations.
- Knowledge of Constellations came from early cultures
Much of the knowledge about constellations dates back to as early as the late bronze age. Even the initial knowledge that Greek had was inherited from Egypt who again inherited it from ancient Babylon and Sumeria.
- Different Constellations become visible throughout the year
With Earth’s constant revolution and rotation, we can see different constellations at various times in a year.
- Each month more Constellations appear in Eastern sky
Each night more constellations become visible in the east than the night before with a daily shift rate of around one degree per day. This apparent shift is explained by the fact that there are 365 days in an Earth year, while there are 360 degrees in a circle.
- Constellations seem to rotate in a counter clockwise direction
The constellations appear to rotate counter clockwise around a fixed point in the night sky known as the north celestial pole, located near the north star Polaris.
- Zodiac Constellations found where Sun, Moon, and Planets move
The most commonly known of all the 88 constellations are those of the Zodiac. All the Zodiac constellations appear within a 23.5 degree wide band of sky called the ecliptic plane.
- Some Constellations have families
A constellation family refers to a group of constellations located within the same region of the night sky. They usually take their names from their most important constellation, like the Hercules Family (19), the Ursa Major Family (10), the Perseus Family (9) and the Orion Family (5).
- Notable Constellations
The Centaurus constellation contains the largest number of visible stars numbered at 101; while the biggest constellation is Hydra which extends over more than 3% of the night sky.
- Asterism not considered true Constellation
An asterism is a pattern of stars that are widely recognized and contained within an official constellation but is not counted as a true constellation in itself, for example, The Big Dipper.