Category: Planets

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Constellations of the Zodiac in Order

Learning the Zodiac constellations in order is a great way to get familiar with the ecliptic and the celestial sphere. The Zodiac is not just for astrology – astronomers use the constellations of the Zodiac to name 13 regions of the sky.

Zodiac Constellations zoomed in on Ophiuchus – the “13th” Zodiac Constellation between Sagittarius and Scorpio. The constellation borders (marked red) show how astronomers divide up the sky into named regions.

Zodiac Constellations List

These are the Zodiac constellations in the correct order from Aries to Pisces.

OrderMnemonicNameDescriptionEmojis
1AllAriesRam♈ 🐏
2TheTaurusBull♉ 🐄
3GreatGeminiTwins♊ 👯‍♂️
4ConstellationsCancerCrab♋ 🦀  
5LookLeoLion♌ 🦁
6VeryVirgoVirgin♍ 👰
7LovelyLibraScales♎ ⚖️
8ShiningScorpioScorpion♏ 🦂
9OrderlyOphiuchusSnake-wrestler⛎ 🐍🤼‍♂️
10StarsSagittariusArcher♐ 🏹
11CreatingCapricornGoat-Fish♑ 🐐🐠
12AnimalAquariusWater-bearer♒ 🚰
13PatternsPiscesFish♓ 🐟
Table showing the order of the Zodiac Constellations, their names, descriptions, and emojis

Memorize the Constellations of the Zodiac in order

This mnemonic (memory device) can help you remember the correct order of the constellations of the Zodiac. This is the best way to memorize the order of the constellations of the Zodiac. It starts with Aries and ends with Pisces.

“All the great constellations look very lovely; shining, (orderly) stars creating animal patterns.”

– Alex Davo (original – orderly added by DC)

This sentence is good too – it’s a little bit more romantic.

“A time gone, cowboys loved viewing little stars, (oh) so cold and pretty.”

Menuonic for remembering the constellations of the zodiaca time gone cowboys loved viewing little stars so cold and pretty

– Terry Johnson (original – oh added by DC)

Why does the Zodiac constellations list start with Aries?

When astrology was invented it was the same activity as astronomy – observing and cataloging sky objects and their locations) but over the years the two practices have become very different. Astrology is now concerned with how the movement of the skies affects humans while astronomy has become a science. Scientists build knowledge to make predictions about physical events.

During early astrology/astronomy times, the most important thing about the study of the stars was to know where the Sun, Moon, planets, and other solar system objects were located in relation to the steady, orderly background of stars.

Why does the order of the Zodiac constellations read right to left?

The Sun moving “through” Aries into Taurus over a month. Each frame of the animation is about 3 days.

The Sun, Moon, and planets seem to move “through” these 13 constellations in order through the year. Starting with Aries, let’s follow the movement of the Sun against the backdrop of the steady stars. The next constellation that the Sun “moves into” is Taurus. Taurus is to the east (left) of Aries! The Sun appears to move into the next Zodiac constellation about once a month.

We know that the Sun is not moving – that it only appears to move through the sky – and that it is the Earth’s orbital motion that is creating this apparent movement.

Why did we add Ophiuchus to the original 12 Zodiac constellations?

Ophiuchus is a constellation, not an astrology “sign.” However, it is an official constellation that intersects the ecliptic. So, while astrologers do not consider this a Zodiac sign, astronomers include it because the constellation is located on the ecliptic.

The Ecliptic is a path in the sky that solar system objects follow

The solar system objects move generally west-to-east in a small band of the sky – this band of sky is called the ecliptic. All the Zodiac constellations are “on” the ecliptic and all the Sun, Moon, planets and other solar system objects move along the ecliptic over time.

There is another line in the sky called the celestial equator that is an imaginary line the rises from the equator of the Earth. The celestial equator and the ecliptic intersect at a “location” in the sky.

Right now in 2020 that intersection location is “in” the constellation Pisces.

The thin, diagonal line that connects the Zodiac constellations is called the ecliptic. This image shows the ecliptic intersecting with the celestial equator.

However, when astrology was created this intersection point was “in” the constellation Aries.

This image shows the intersection of the ecliptic with the celestial equator in the year 100 BCE.

This was known as the “First Point of Aries.” Astronomer Guy Ottewell writes about this imaginary point in the sky on his website UniversalWorkshop.

Summary

You can learn the order of the Zodiac constellations by using the mnemonic device shown in this article. There is a pathway in the sky that the solar system objects seem to follow. It is called the ecliptic. The Zodiac constellations are the 13 constellations lined up in the sky “on” this imaginary line.

The order of the Zodiac constellations is made because of the way the Sun, Moon, and planets seem to move east-to-west past these constellations in order during the year.

We start the Zodiac names list with Aries because the Zodiac constellations were first named thousands of years ago. At this time, the ecliptic intersected the celestial equator “in” the constellation Aries.

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How can I see Venus?

You can see Venus in the sky at two times and locations:

  • in the early evening, shortly after sunset in the west or
  • the early morning, shortly before sunrise in the east. 

Venus orbits the Sun and moves from evening sky to morning sky and back again over the course of about 18 months. Venus makes beautiful sweeping motions in the sky that reveal secrets of the solar system.

See Venus, see the plane of the solar system

Solar system plane
The planets all orbit the sun in the same plane. Image not to scale.

All the planets in the solar system orbit the sun. All of the orbits line up in neatly nested concentric rings. And all of the rings are lined up with each other as if they are placed on a single surface together.

The orbits are all in the same plane. It’s like they are all marbles circling around the sun on the same giant plate. This is called the “ecliptic” and it is visible in the sky if you know how to find Venus.

Intersecting space planes

The “space plane” is not an airplane

The “plane” is a tool you can use to see the way things move in space. This “plane” is not an airplane, but a flat slice of space.

Here is an image of two intersecting planes. Imagine the blue plane is the earth’s surface and the brown plane is up-and-down from ground to sky.

Each object (and movement) in space creates a “plane,” an imaginary slice through physical space. The blue “plane” above looks like the surface of a pond, lake or ocean. A wall or roof of a house is a plane. A dinner plate is a plane. Stretch your arms out and spin in a circle and you have created a plane with your arms.

There are planes in space everywhere.

Your own personal space plane

You create a plane with your vision and balance. You can imagine a flat surface like the surface of a pool of water and your eyes are just above the waterline. This surface moves and tilts when you move your head.

Your head has two eyes that define your plane of vision. Also, your body is oriented to gravity because of your sense of balance – the “personal horizon” is the first plane for you to orient to. Your body naturally coordinates your visual sense with your sense of balance and gives us the sense of being located level on a surface. This is the “sense of horizon.”

A new horizon – choose a plane!

To get good at Physical Astronomy, we have to learn to coordinate our main “personal horizon” plane with other planes of the earth, moon, solar system, galaxy, and universe.

The earth for instance, has a lot of planes, the range of latitudes, the north and south poles, the Arctic and Antarctic circles, the equator, the tropics, a range of longitudes, the prime meridian, the international date line, the ecliptic, the galactic plane and more.

To keep things simple, let’s focus on just one other plane for now: the plane of the solar system. A wonderful thing will happen when you learn to link the plane of vision with the plane of the solar system. It’s pretty easy to do, and it’s a skill that gets better with practice.

The key to linking vision and solar system planes is to know that the plane of the solar system is visible as the ecliptic. One easy way to see the plane of the solar system is to see the bright inner planet Venus.

See Venus see the orbit of Venus in the western sky just after sunset. See how the line from Venus to the Sun defines the ecliptic.
See Venus and you can see the orbit of Venus

See Venus and the Orbit of Venus

Venus is closer to the Sun so we are able to see its entire orbit. Actually, we can’t quite see the entire orbit because sometimes it goes in front of the sun and sometimes it goes behind the sun.

We can see Venus in the early evening and in the early morning. Venus is visible in our sky when it is at the left and right extent of its orbit around the sun. We only see Venus in the sky when it is swooping around the left or right of the sun.

If you want to see the orbit of Venus and see the plane of the solar system you can do it! All you have to do is imagine a line connecting Venus to the Sun.

If you are looking at Venus early in the morning before sunrise or early in the evening before sunset, the process is the same. Imagine a line connecting Venus to the Sun; this is the ecliptic. Venus’s entire orbit covers roughly 1/4 of the sky.

Summary

We learned about two main planes in space: your personal horizon (which changes as the Earth carries you around the Sun) and the plane of the solar system: the ecliptic. 

By learning to visualize these two space planes, we can begin to experience the extremely large dimensions of space.

References

Venus information from In the Sky.

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See Mercury and Venus orbits during the day

Your hands and arms help you see the orbits of Mercury and Venus and the shape of solar system

Question: If you could see the orbit of Venus would it fill the whole sky?

The answer might surprise you!

You can use your hands and arms to see the size of the orbits of the solar system’s inner planets: Mercury and Venus.

Imagine (as pictured below) if the orbit of Mercury were visible as a red oval and the orbit of Venus were visible in green.

Use your hands and elbows to see Mercury and Venus orbits any time of day or night. The orbits of Mercury and Venus can be seen.
Two hand spans show the orbit of Mercury, elbows show the orbit of Venus.

Physical Astronomy – see Mercury and Venus orbits

Caution! Do not look directly at the Sun without proper solar safety glasses on.

Turn toward the Sun, hold your arms out straight, hands up in the air with fingers spread wide and thumbs touching. Your pinky fingers now span the width of the orbit of Mercury and your elbows span the width of the orbit of Venus.

Both of the entire orbits of Mercury and Venus orbits would be visible in the sky all at once – if they could be made visible during the day.

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