Constellations What is a constellation?
A constellation is a group of visible stars that form a pattern or an imaginary shape
when viewed from earth.
The picture on the left shows a
constellation named Ursa Major. The patterns formed by the stars can be any shape – a man, a woman, an animal, a mythological creature, or even
an object such as a crown.
The picture on the left shows a
constellation named ‘Orion’. Ancient Greeks were the first people to describe constellations. Almost all of the constellations have a myth (story) associated with them – mostly mythological figures
who were given a place in the sky by the Greek gods. There are 88 named constellations. 48 of them are ancient listed by the Greek astronomer Ptolemy and 40
of them are new.
Greek astronomer Ptolemy The celestial sphere is how astronomers map out the sky. It is an imaginary sphere to map out the constellations and to know where everything is at a certain time of the year. It is important because constellations move around
naturally as Earth moves. If you want to find a specific constellation in the sky you might need to use a star map. Star maps are divided by hemispheres because the entire sky will be too hard to fit in one map. For example a map of the northern hemisphere shows
constellations above the equator. Constellations are categorized into two types – circumpolar constellations (which are always seen in the sky), and seasonal constellations (which are only
seen for a part of the year).
The picture on the left shows ‘The Big Dipper’. It is a circumpolar
constellation. Constellations were used to help keep track of the calendar
in ancient times.
The picture above shows a constellation for each
month of the year. Constellations also helped with navigation. For example, if you spot Polaris and travel in that direction, you would be traveling north. Because of constellations, ships were able to travel around the globe. It allowed for the discovery of
America and the spread of European culture. Fun Fact #1 The sun is the only known star in our galaxy that is not
part of a constellation. Fun Fact #2
Farmers were the first to use constellations. Because of the changing seasons, the farmers depended on the stars to know when it was time to plant and when it was the right time to harvest. Fun Fact #3 Has anyone ever asked you what your zodiac sign is? Are you a libra, Scorpio, a Gemini? There are 12 zodiac constellations used as signs for the
zodiac calendar and astrology.
Aquarius Fun Fact #4
22 different constellation names start with the letter “C”.
1. Caelum 12. Cetus 2. Camelopardalis 13. Chamaeleon 3. Cancer 14. Circinus 4. Canes Venatici 15. Columba 5. Canis Major 16. Coma Berenices 6. Canis Minor 17. Corona Austrina 7. Capricornus 18. Corona Borealis 8. Carina 19. Corvus 9. Cassiopeia 20. Crater 10. Centaurus 21. Crux 11. Cepheus 22. Cygnus Fun Fact #5 Hydra is the largest constellation by
area which takes up 3.16% of the sky.
Hydra is also known as the water snake.