What are constellations?

Constellations are not "real" and therefore, were never discovered. Humans have invented constellations as easy-to-remember patterns in the night sky. They are mainly used to help us distinguish which stars are which.

When were constellations first "invented"?

They can pretty much be traced back to the beginning of recorded history, to about 4000 BC in Sumerian board games. By 450 BC, the Babylonians divided the zodiac into the 12 signs, which we still use today. The way we study and learn about constellations today is based mostly from Egyptian astrology.

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The significance behind the 12 zodiac signs stems from the path in the sky that the Sun, Moon, and planets seem to follow and how they run through the 12 signs.

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What is the importance of constellations?

Since different constellations are visible at different times during the year, it is easy to tell which month it is. This was particularly helpful to farmers during ancient times to differentiate between the seasons. Constellations are also very useful for astronomers and people studying astrology because they divide the night sky into smaller regions, providing a kind of universal language within the stars.

How many constellations are there and how were they named?

There are now 88 constellations: the brightest one being Crux (the Southern Cross), the one with the greatest number of visible stars is Centaurus (the Centaur with 101 stars), and the largest constellation is Hydra (the Water Snake). There are asterisms as well, smaller groups of stars within a constellation, like the Big Dipper in Ursa Major. Most names for constellations are in Latin, dating back to the Roman Empire.

The first use of constellations was probably for religious reasons when people thought that the Gods in Heaven created them. Many cultures believed that this was the Gods' way of showing them something improtant so they recognized the patterns, and started telling stories with them. The names that we use today to distinguish the constellations are from the Greeks, who named the patterns after their own mythological heroes and legends. In this way, the constellations all have stories behind them.


What's special about them?

Part of the fascination with them stems from being around so long-- even ancient civilizations recognized them and they mostly immortalize myths, stories, and heroes. They're also universal; like, the British call the Big Dipper a Plough, the people in Southern France call it a Saucepan, and the ancient Mayans called it a mythological parrot named Seven Macaw.

Other information:

  • Because of the rotation of the Earth and its orbit around the sun, constellations are divided into two groups -- circumpolar (meaning they never rise nor set) and seasonal constellations (which are all the rest of them) and which is which depends on your latitude.

Current Events:

After the International Astronomical Union's (the group of people who assign names to celestial objects) officially recognized the list of the 88 constellations that we use today, there has been no need to name anymore.

Personal Opinion:

I personally find constellations to be an interesting topic because I never really understood them myself. I used to always go to the planetarium growing up, but whenever they pointed out the constellations in the stars, I never understood how they got the image that they did. I mean, the stars didn't even match up or anything. Now I understand that the ancient constellation-makers were probably trying to be more symbolic than literal representations. Additionally, I think that it would be a good experience to go outside one night and try locating these for myself.


For more information on the different constellations:

Sorted by Seasons

Northern Hemisphere Constellations
Southern Hemisphere Constellations
Myths about the Different Constllations

Other Sources: