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.

Order	Mnemonic	Name	Description	Emojis
1	All	Aries	Ram	♈ 🐏
2	The	Taurus	Bull	♉ 🐄
3	Great	Gemini	Twins	♊ 👯‍♂️
4	Constellations	Cancer	Crab	♋ 🦀
5	Look	Leo	Lion	♌ 🦁
6	Very	Virgo	Virgin	♍ 👰
7	Lovely	Libra	Scales	♎ ⚖️
8	Shining	Scorpio	Scorpion	♏ 🦂
9	Orderly	Ophiuchus	Snake-wrestler	⛎ 🐍🤼‍♂️
10	Stars	Sagittarius	Archer	♐ 🏹
11	Creating	Capricorn	Goat-Fish	♑ 🐐🐠
12	Animal	Aquarius	Water-bearer	♒ 🚰
13	Patterns	Pisces	Fish	♓ 🐟

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.”
– 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.

July 8, 2020July 8, 2020

Seeing The Zodiac – A Stellarium Script Tutorial

🔭 I am a Live Planetarium Presenter – “Planetariumist” – at the Fresh Air Fund’s Gustafson Planetarium at Sharpe Reservation in Fishkill, NY. We Planetariumists are learning to use Stellarium scripts. This article will teach you how to use a Stellarium script to quickly load the art images for the 13 Zodiac constellations:

Aries Taurus Gemini 
Cancer Leo Virgo 
Libra Scorpius (Ophiuchus) Sagittarius 
Capricornus Aquarius Pisces

Inside view of Daniel Cummings presenting Stars are Alive at Gustafson Planetarium at Sharpe Reservation in Fishkill, NY — A selfie from inside the Gustaffson Planetarium at the Fresh Air Fund Sharpe Reservation in Fishkill, NY

Online Camp programs for Astronomy Education

Like every other camp program during COVID-19 times we have had to move the live shows to an online format. In our case we are doing zoom astronomy presentations for the campers. It’s been a great experience to learn how to do quick and entertaining astronomy shows online and I wanted to share a few tips to make better astronomy online presentations.

Stellarium Scripts for Astronomy Zooms

I want to make Stellarium really work for online presentations like zoom astronomy outreach, so I figured out how to write scripts to control it. To get started, I just copy-pasted and modified an existing script that did something like what I wanted it to do.

Zodiac Art in Stellarium showing the Sun “in” Gemni on July 8, 2020 from Flushing Meadows, Queens, NY

Stellarium scripts help you do the tedious set up and configuration steps. There is no need to open windows and drag and click around while your audience waits!

Below is a Stellarium script I adapted from the original zodiac.ssc that highlights the Zodiac constellations with art, names, and boundaries and it shows the ecliptic. The original script that comes with Stellarium had some features that I didn’t need so I copy-pasted a new one. My new script simply shows the Zodiac constellation art in just 5 seconds. This would take at least a minute to complete by hand! So, this is a great timesaver if you are presenting to a group via online zoom conference.

Stellarium Script – show Zodiac Art, Boundaries, Ecliptic

You can click here to download the script as a zip file. Unzip this download and you will have the .ssc file in your downloads area. Or you can just copy-paste the text below and create your own script file.

Here is a quick gif animation of what the presentation screen looks like while loading the Zodiac Art Boundaries and Ecliptic in the Stellarium Astronomy Zoom presentation.

An animated GIF showing the end result when you install the new Zodiac script.

Using the New Zodiac Art Boundaries and Ecliptic Script – Tutorial

Installing scripts is as easy as creating a text file with this script and placing the “script_name_here.ssc” file in the scripts directory. In this case, name your script file: zodiac_art_boundaries_ecliptic.ssc

After this “Zodiac Constellation Art Boundaries Ecliptic” script is installed in your Stellarium you’ll be able to get to it and run it from the Scripts tab of the Configuration window.

Screenshot of Stellarium script configuration window.

Instructions to Install a Stellarium Script

On Windows: You have to find the Stellarium User Data directory and inside that will be the scripts directory. (NOTE: I don’t have a windows machine so there is probably more information required here. Please add a comment to this post if you discover that I have left something out.)

C:\Users\YOURUSERNAME\AppData\Roaming\Stellarium

If it doesn’t already exist, create a new folder named “scripts” – leave out the quotes.

Windows file explorer view of where to place the script.

Move your downloaded or created .ssc file to this folder.

On Mac: you have to control-click (hold the control button and click the mouse) the Stellarium.app in the Applications directory and choose “Show Package Contents”

Screenshot showing how to use control-click access Stellarium Scripts in MacOSX

You then navigate to the scripts directory in: Contents > Resources > scripts.

Screenshot showing how the directory path to Stellarium Scripts in MacOSX

Place the script file in the scripts directory. Quit and re-open Stellarium and the script will be in the list of scripts in the Scripts tab of the Configuration window (see graphic above earlier in the article).

If you want to be fancy and use the included key command …

Using Stellarium Script Trigger “Sequence” commands

This custom Stellarium Script comes with a key command I programmed which is a “sequence command” – two steps. First do Control/Command-D, then release those keys and type the letter z key.

Try out the script and let me know what you think by typing in the comments field below! Also, if you want me to write a custom script to speed up your Stellarium presentations I’d love to help out – give me your suggestions.

Stellarium is a potent tool to help you see the sky

I have written few other articles about using Stellarium.

Stellarium – a gift to Humanity – Learn to see the sky

Time Travel with Stellarium – See the sky in timelapse!

Stellarium and the Humanity Star – a short-lived satellite

See the Analemma with Stellarium

About the author of this Stellarium script tutorial

🔭 Hello! I am Daniel Cummings – the creator of the fun and fashionable science clothing The Moon Hat (Forbes named it Best Science Gift in 2018). I am also one of the Live Planetarium Presenters – “Planetariumists” – at the Fresh Air Fund’s Gustafson Planetarium at Sharpe Reservation in Fishkill, NY. I’ve written about and presented astronomy and space topics since 2008. Sign up on my email list to hear more about astronomy and space.

September 24, 2018September 26, 2018

How many stars are in the sky? A Quiz

Have you ever looked up and wondered how many stars are in the sky?

This person is wondering how many stars are visible in the sky right now. — How many stars are in the sky right now?

It’s a simple question with a surprising answer!

This question has layers of answers – the most common answer is “it depends” – it depends on where you are, what part of the year it is, what time it is, and most of all… how dark are your skies and how powerful is your telescope?

Let’s start with a quick (approximate) list of how many stars you might be able to see at once at night under “normal” conditions with no telescope. (The details on these calculations are near the end of this article.)

How many stars can I see at night:

The most stars anyone can see from the Earth (no telescope): 3700
The number of stars can you see at a dark sky site: 2000
How many stars can I see in my suburban yard: 200
How many stars can I see in a large city: 20

Another trick answer to “how many stars are in the sky?” is: “all of them!” All of them are in the sky, but they are just not visible to you “right now” for one reason or another.

I know, these answers are not quite what you may be looking for. Let’s look a little bit deeper by starting our search for how many stars can I see at night.

Quiz – How many stars are in the sky, how well do you know them?

Let’s start by taking a short quiz (answers are just a scroll away, so don’t peek!):

Which star is the brightest in the sky?
Which star is the closest to us?
Which star is the first one discovered to have a planet supporting life?
Which stars have a solar system?

Scroll down a bit to see the answers to this first part of the quiz.

While we are waiting to scroll (and to keep the peekers from peeking!)… let’s talk a little bit about how professional astronomers count the stars.

Annie Jump Cannon – Harvard star counter extraordinaire

Astronomer Annie Jump Cannon found a lot of stars and classified them — Annie Jump Cannon – Harvard University Image: Public Domain

Have you ever tried to count the stars? If you have, you probably gave up at some point because there were too many to keep track of.

In the early 1900s there was a tenacious Harvard astronomer named Annie Jump Cannon who didn’t give up counting! In fact, she counted so many stars that she almost lost track.

To keep everything organized she started categorizing them by their colors. She invented the spectral classification system – O,B,A,F,G,K,M – and personally classified over 350,000 stars!

Her method of categorizing stars is still in use today.

The answers to the star Quiz

The Sun is one of many stars. Proxima Centauri, Sirius, Arturus and Rigel are shown in a size comparison. — The Sun compared to other stars. Image: Daniel Cummings

The number of stars in the sky is…

SPOILER ALERT! – Here are the answers to the quiz above!

The quiz is a trick quiz because the answers to are all “the Sun.” If we don’t include the Sun in this quiz then we get very different answers and the answers are:

Sirius is the brightest star (it is almost as bright as Jupiter),
Proxima Centauri is the closest star (it is 4.22 light years away),
No star’s exoplanets have yet been proven to support life – the Sun is the only star so far to host life.
There is only one solar system. The answer to question 4 is truly a trick question: “No other stars have a solar system… because only one star is named “Sol” … the Sun! The “Solar System” is named after Sol – the Sun. See: Sol+ar = Solar. Other stars would have planetary systems named after the star. For instance, there may be a “Sirius-ar system” that hosts a planet like Earth.

The Known Universe

Ok, now you are done with the quiz let’s get counting stars. Go outside, look up, start counting!

How many stars are in this picture? We may never know since the know universe keeps growing — Artist’s conception of the known universe. Credit: Pablo Carlos Budassi via Wikipedia

Before, we start… There is one tiny problem with counting the number of stars. Even with the best tools humans have invented, we can only see a small part of the universe. Astronomers call this the “known universe” and it stretches about 14 billion years back through time in one direction, and (we assume) 14 billion years back in another direction.

Ten sextillion stars in the known universe

Astronomers have estimated the number of stars in the Milky Way galaxy as one hundred billion (this is a low estimate by the way). The Milky Way is an average galaxy. Astronomers estimate that there are one hundred billion galaxies in the known universe (another low estimate). The math to figure out the total number of stars in the universe is as simple as the result is mind-boggling!

100,000,000,000 (one hundred billion – 11 zeros) x 100,000,000,000 (one hundred billion – another 11 zeros) = 10,000,000,000,000,000,000,000 (ten sextillion – 22 zeros)

Counting to one million is not like Counting to one billion

A million is way, way smaller than a billion.

It would take 11 days to count to one million if you counted one number per second without doing anything else. Counting to a billion at the same pace (one per second) would take you 32 years of continuous counting!

Count to 1 million at a rate of 1 per second = 11 days
Count to 1 billion = 32 years
– Arithmetic

If you counted all the stars in the Milky Way at the rate of one per second, it would take you about 3200 years to finish counting our one galaxy’s set of stars.

How many stars in my sky now?

Ok. So, let’s get real. Now we know how many stars there may be in the entire known universe, let’s narrow the question.

Here is how we will narrow the question. Let’s create a set of ideal conditions that will guarantee we see as many stars as possible.

This is the set of almost ideal seeing conditions. This set of conditions would guarantee seeing the most number of stars that anyone could ever see with the naked eye:

I am on a tall mountain top with no trees looking up at the perfectly clear and calm sky right now. It is midnight. I can now see approximately half the stars in the sky. These near perfect seeing conditions make it so that I can see stars to magnitude 6 with my 20/20 vision.

Number of stars in the sky I see

According to David Haworth of Stargazing.net there are approximately 7400 magnitude 6 or brighter stars. Remember, we can only see half the sky at any time. So, cutting 7400 in half we get 3700 stars. 3700 stars is the greatest number of stars that any earth-bound human can ever see at any one moment without a telescope or other aides.

Stars in my sky right now

Now we know how many stars you might ever see at once, let’s look at how most people see the sky.

Most people cannot see 3700 stars because of serious light pollution, horizons full of trees and landforms, and atmosphere, lots of watery, moving atmosphere floating above us.

If you are lucky and go camping in a dark sky area you might be able to see about 2000 stars on a good night.

In a typical, light-polluted suburban sky you can see approximately 200-300 stars.

In the middle of a big city the number of stars goes down to about 12 to 20.

12 Stars.

12. That’s not a lot of stars. Maybe take a trip out of the city to see the stars?

Summary

You can see 3700 stars under perfect viewing conditions.

You can see about 2000 under excellent dark skies.

You can see about 300 stars in the suburbs.

You can see 12 stars under bright city lights.

References for how many stars

Stargazing.net – David Haworth compiled data on the number of stars at each magnitude and presented it in a nice table.

Sky and Telescope article – covers skyglow, light measuring technology, light maps, NELM and more. Authoritative.

Space.com article – how astronomers estimate the number of stars in the Milky Way.

National Geographic Kids – Mini article on light pollution with estimates on how many stars are visible from different places.

August 20, 2018August 21, 2018

Track the Sun

So you want to track the Sun?

You don’t need to build your own Stonehenge. You can track the Sun’s position in the sky and learn how to do astronomy during the day!

Let’s get started with the basics of sun tracking. Here is everything you need to know to begin:

The Sun does not move; the Earth moves – it carries us under the Sun – it just looks like the Sun is moving.
The Earth moves every second of every day so the position of the Sun changes every second of every day.
Night is not the “Sun going away”, it is the Earth blocking the Sun.

One Day of Observation: the Sun rises and the Sun sets

Let’s start with a few easy observations about daytime. These are things you can notice just by waking up early one day before the Sun brightens the night.

The Sun starts the day for us on one side of the sky and ends the day on another side. At both of these times (sunrise and sunset), the Sun appears near to the ground – at the horizon.

During the middle of the day, the Sun appears to move “up” and across the sky and then back “down” again. In the middle of the day – at noon time – the Sun is high up in the sky, away from the ground.

Shadows change during the day

In the morning the Sun makes long shadows. At noon the Sun makes short shadows. At the end of the day, the Sun makes long shadows again.

With a few simple tools you can measure the Sun’s position and shadows.

The Sun moves east to west

Over the course of one day, the Sun appears to move across the sky from east to west, rising to the highest point at noon. The Sun’s light shines on the Earth and makes shadows that move and change position and size. As the Sun “moves” through the sky, the shadows move on the ground.

Build a simple sundial, track the Sun

Sundial in Krk, Croatia showing the gnomon (stick) casting a shadow onto the marker at XII 12 o'clock noon. The shadow is shortest at 12 noon and allows people to track the sun. — Sundial – Krk, Croatia. The gnomon (stick) casts shadow on marker at XII 12 o’clock noon. Image credit: Pixabay.com

A sundial tracks the shadow of the Sun with an object that casts a shadow and time markings. For the simple sundial you can use a stick. The shadow of the stick (the stick on a sundial is called a gnomon) moves across the sundial. The shadow of the stick points to the time markings.

The simplest sundial is just a stick stuck in the ground with time markers nearby. The location of the stick’s shadow moves across the time markers throughout the day.

A stick, the Sun, another stick marks shadow. As simple as it gets. Image: Jim Champion

Mark the shadow’s position with any object (chalk drawing, a rock or another stick is a good choice). In the morning, the Sun appears low in the east and the shadow is long. The morning shadow points toward the west. At midday (noon) the Sun is at the highest point so the shadow falls in the middle and becomes short. At sunset, the shadow becomes long again – pointing to the east.

Paper Plate Sundial

A paper plate and a pencil make a simple sundial to track the Sun. — Push a pencil through a paper plate to make a sundial. Image Credit: Daniel Cummings

A paper plate with a pencil stuck through the middle makes a great moveable sundial! (Remember, when you move a paper plate sundial, you have to be careful to place it in perfect north-south alignment.)

Take this outside on a sunny day, then make a mark on the paper plate at the top of each hour. The shadow will move slightly each hour. The mark should go at the middle of the pencil shadow.

When you have completed this during one sunny day, you have made a sundial that can tell the time – roughly speaking!

An indoor sundial – the Sun Tracker

Most people think of sundials as something that you place outside. But, the Sun shines inside through windows. You can track the Sun through a window.

The Sun Tracker helps you track the Sun. It works as an indoor sundial that lets you decode the secrets of the motions of the Sun and Earth. It can track the Earth's rotation and orbit around the Sun.

An indoor sundial can help you track the Sun from the comfort of your own home! Do you have a sunny (or partly sunny) window? You can track the Sun and reveal the secrets of the Earth’s motion.

The Sun Tracker is an easy-to-use indoor sundial. Place the glistening window cling on any sunny window and then mark the position of the window cling’s shadow using one of the included stickers.

Repeat the next day or the next week at the same time of day. You will see a pattern emerging: the shadow cast by the Sun moves quite a bit each day.

If you are extra precise with recording the shadow at the same time of day, and you are able to do it for an entire year… you will see the Analemma.

The Sun Tracker is like a little bit of Stonehenge for your window.

Summary

Track the Sun with simple tools and you will reveal the motion of the Earth. There are two main motions of Earth, daily rotation and yearly orbit. Earth spins under the Sun each day and around the Sun in an orbit each year.

It is these two motions that make the Sun seem to move in the sky. Remember that the next time you are looking for the Sun – it’s where it always is… the Earth is what moves.

June 27, 2018January 29, 2019

Where is the Sun?

Where is the Sun right now?

Can’t see the Sun? Maybe there is something blocking it. Here is a list of 10 surprising things that can block the Sun.

IMAGE of floating/flying things overhead (in roughly size order) that can block all or part of the SUN: Flying animals (Bugs, Birds/Flying Mammals), Flying objects (Drones/Balloons/Airplanes/Helicopters/Rockets/Bombs/Blimps), Smoke/Clouds, Spacecraft (Satellites/Space Stations/UFOs), Asteroids, Moon, Mercury, Venus, Earth. — Things that block the Sun.

Where is the Sun during the day? On a clear day, this is a very simple question. The Sun is “up there” in the sky – it’s a big, bright, fiery ball and it’s generally a yellowish orange color. You just point to it – there it is, up in the sky, the Sun.

However, many things can block the Sun. Usually, it is clouds that block the Sun, but not always. Let’s take a tour of the astonishing number of things that can block the Sun.

Click here to continue reading…

February 26, 2018October 2, 2018

Merry-Go-Round Earth shows Seasonal Constellations

The Earth is like a Merry-Go-Round

Merry-Go-Round Earth model demonstrating how the seasonal constellations work — A Merry-Go-Round is a good model of daily Earth rotation.

The Earth is like a merry-go-round showing us seasonal constellations

That iconic childhood ride. Round and round each day we go, round and round each year we go, where we stop nobody knows! When we look out from the edge of the ride we can see the space beyond. Sometimes the Sun occupies that space, and sometimes that space is the night sky filled with stars.Click here to continue reading…

February 13, 2018July 27, 2018

Quiz – Can we see the Sun at midnight? Where is the Sun?

Can we see the Sun at midnight?

Yes. We can see the Sun at midnight. But, only if we are at one of the polar regions during the Summer season.

A quiz – seeing the Sun at midnight – don’t scroll til you try to answer!

When you see the Sun “rising” in the morning at dawn you are facing the east.

When you see the Sun “setting” at the end of the day you are facing the west.

Assuming you are not above the Arctic circle and not too close to the equator… if you could look right at the Sun (when the night is exactly half over) – by looking through the Earth – which cardinal direction would you be facing? East, West, North, or South?

Looking north or south to see the Sun at midnight? — A compass rose showing the cardinal directions.

Click here to continue reading…

November 11, 2017May 1, 2018

Stellarium – See the Analemma

See the Analemma

Stellarium can help you see sky patterns and practice Physical Astronomy.

Video of the Analemma in Stellarium:

By following this article you will be able to see the analemma moving – a figure 8 shaped path that the Sun follows yearly.

Click here to continue reading…

September 26, 2017July 27, 2018

Tilt Head to Tilt Earth – Seasons are caused by a tilted Earth

Physical Astronomy by Daniel Cummings

Seasons are caused by a tilted Earth

Use this technique to understand how seasons happen on the Earth. The Earth is tilted. When the northern part (your forehead and eyes) tilts away from the Sun the season is winter. When the northern part tilts toward the Sun the season is summer.

The Earth is tilted as it spins daily – it is not straight up and down like a top, but more like the Leaning Tower of Pisa (if the tower could spin!). As it goes through its yearly orbit, the Sun hits the northern and then the southern parts of the Earth.

Tilt your head to tilt the Earth

In this model, when the northern part (your forehead and eyes) tilts away from the Sun the season is winter. When the northern part tilts toward the Sun the season is summer.

Did you like this season model? Any questions? Type in the comments to send me a message.

June 27, 2017