The Auriga Constellation – Facts in brief:
What is it? –
The Auriga constellation is associated with 2 characters from Greek mythology: Erichthonius (King of Athens and inventor of the four-horse chariot) and Myrtilus (the divine hero and son of Hermes).
The name ‘Auriga’ is Latin for ‘the Charioteer’.
The Auriga Constellation is regarded as a fairly old constellation, as it is one of the original 48 Constellations listed by Greek Astronomer Ptolemy, in the 2nd century.
Auriga is also one of the official International Astronomical Union (IAU) listed 88 modern constellations as seen in the night sky from Earth and listed as the 21st largest Constellation overall, filling around 1.6% of the night sky.
Auriga, abbreviated to ‘Aur’, or ‘Aurigae’ (its Latin name) is quite easy to recognize, as it resembles the outline of the Charioteer, from Greek mythology.
The Constellation of Auriga is a member of The Perseus family, of Constellations, which also includes:
Where is it located? –
The Auriga Constellation is positioned in the first quadrant of the Northern Hemisphere, north of the celestial equator.
It is sometimes referred to as being located in the NQ1 Quadrant.
FACT: The ecliptic is the imaginary line tracing the route that The Sun, the Moon, and the Planets take across the sky, over the year.
The Auriga Constellation is located in an area of the sky close to the northern Milky Way (the winter Milky Way).
Due to its circumpolar nature, the Constellation of Auriga is visible for most of the year in Northern latitudes, but the best month to view it at its best is in February.
There are 5 Constellations that are visible throughout the year, from most locations located north of the celestial equator, making them Circumpolar, they are:
- Cassiopeia Constellation
- Constellation Cepheus
- Draco Constellation
- Ursa Major Constellation
- Constellation Ursa Minor
FACT: A constellation that is visible all year round is known as a Circumpolar Constellation.
There are 3 Southern Constellations that are also circumpolar –
Where can it be seen?
Co-ordinates of a right ascension, or left ascension and their declination are used to locate all of the Constellations, like Auriga.
Auriga is most prominent in the Northern Hemisphere, from January to February. It is not a fully circumpolar Constellation (meaning it’s not visible all year round).
The Constellation of Auriga lies at 6-hour right ascension (with a range of 4 hours 37.5 minute to 7 hour 30.5 minutes) and a Declination of 45 degrees North (with a range of 27.9 to 56.2 degrees North).
It’s easily visible from the Northern Hemisphere at latitudes between +90 degrees and +40 degrees and covers an area of 657 square degrees.
The Auriga Constellation is bordered by several other Constellations:
- Lynx and Camelopardalis – to the North
- Gemini and Taurus – to the South
- Perseus – to the East
- Telescopium – to the West
It is most visible in the Northern Hemisphere during the winter months, in the evening.
How can you identify The Constellation of Auriga?
The simplest method for spotting any particular Constellation from Earth is to locate the brightest star in that Constellation, and then look at the neighboring illuminations, to see if you can identify a recognizable pattern.
There are many different bright stars located within the Constellation of Auriga.
The named Stars in any Constellation are listed in order of luminosity from the brightest Star to the faintest Star. The ‘Alpha’ letter is normally allocated to the brightest star, then ‘Beta’ and so on in decreasing order through the letters of the Greek alphabet.
- In the Constellation of Auriga, the brightest Star is Capella (Alpha Aurigae).
- The second brightest Star is called Menkalinan, (Menkarlina), known as beta Aurigae.
The Star Capella (alpha Aurigae) has an apparent visual magnitude of 0.08.
This visual magnitude makes it the sixth brightest Star overall in the night sky. Alpha Bootes, the brightest Star in Constellation Bootes, is also the brightest star north of the Celestial equator, just clouding Vega and Capella.
The closest star to the galactic anti-center is Elnath (beta Tauri, beta tau). It is a Star that’s located at the southern tip of Auriga and is located around 130 light years from Earth. It is visible to the naked eye and has an apparent visual magnitude of 1.65.
This Star previously belonged to the Constellation of Auriga but due to its closer proximity to the Constellation of Taurus it was reclassified as a part of Constellation Taurus.
There are 66 Stars that make up the main Auriga Constellation.
The Auriga Constellation can be identified in the night sky as the winter hexagon asterism. Auriga has a pentagon shape outline with several blurred star clusters within the outline. It is also represented in other ways, such as the ‘goat-herder’.
The brightest stars of Auriga can be viewed from Earth, from a northern location, by the naked eye.
The Star System within Auriga
The Constellation of Auriga has 10 main Stars making up the imaginary outline of the charioteer holding a she-goat with her 3 kids.
The bright stars forming the shape of ‘Charioteer with his goats’, listed from brightest Star to fainter stars:
- Capella (Alpha Aurigae, alpha aur) – a Quadruple Star System, of 2 binary stars
- Menkalinan (beta Aurigae, beta aur)– an eclipsing spectroscopic Binary Star system
- Mahasim (Theta Aurigae, theta aur) – a Binary Star
- Hassaleh, or Kabdhilinan, (iota Aurigae, iota aur) – a Bright Star
- Almaaz (Epsilon Aurigae, epsilon aur) – a multiple Star System, an unusual eclipsing binary system
- Haedus (Eta Aurigae, eta aur) – a Bright Star
- Sadatoni, an Arabic name, (Zeta Aurigae, zeta aur) – an eclipsing Binary Star
- Prajapati (Delta Aurigae, delta aur) – an Binary Star
- Nu Aurigae – an evolved Giant Star
- Pi Aurigae – a single red-hued Star
- Kappa Aurigae – a Bright Star
- Tau Aurigae – a Bright Star
The 10 named Stars within Auriga that have been approved by the International Astronomical Union (IAU) are:
Almaaz; Capella; Haedus; Hassaleh; Licilinburhuc; Mahasim; Menkalinan; Nervia; Saclatini and Tevel.
Location of Auriga
Auriga can be spotted in the Northern Hemisphere, also referred to as the Northern sky.
The Constellation Auriga is surrounded by various recognizable Constellations such as Taurus, Gemini, Lynx, Camelopardalis and Perseus.
The Auriga Constellation is used as a guide-point in the sky used by astronomers and amateurstargazers to identify certain Deep Sky objects.
When to see the Constellation Auriga
The best months to spot the Constellation of Auriga in the Northern Hemisphere is January and February.
The best time of day to spot it is early to mid evening (22.00 Daylight Saving Time) local time around the world.
How was it formed, found and named?
The word ‘Auriga’ is actually from an ancient Hebrew root meaning ’Shepherd’ possibly a goat shepherd. The main goat is referred to as Alioth, which is Hebrew for a ‘She-Goat’.
The outline of Auriga
The shape of the helmet of the Charioteer representing the Constellation of Auriga comes from the position of its main Stars.
You will have to use your imagination using the following Stars as part of the outline of this asterism.
The constellation of Auriga is sometimes sketched as a Charioteer holding the reins of the chariot with his right hand and holding a she-goat and her two kid goats in his left hand:
- Menkalinan (beta aur) – represents the right shoulder of the rein holder
- Pi aur – represents the left shoulder of the Charioteer
- Capella (alpha aur) – represents the body of the little goat,Amalthea, the she-goat that suckled Zeus
- Almaaz (epsilon aur) – represents the Billy goat (in Arabic) or Nanny goat (in Latin)
- Haedus (Eta aur) – represents the Kid goats of this asterism
- Sadotoni (Zeta aur) – also represents the Kid goats
- Hassalah (Iota aur) – represents an ankle on one leg and a knee on the other of the Charioteer character
What’s within the Auriga Constellation?
The Constellation of Auriga is formed by of a number of different components – mainly Stars, Deep Sky Objects and Messier objects (galaxies).
The Auriga Constellation contains:
- 10 main Stars
- 4 X-ray Stars (2 Binary Stars)
- 8 stars that host an exoplanet
- 2 associated meteor showers known as the ‘Aurigids Meteor Showers’
- ‘The Alpha Aurigids’
- ‘The Delta Aurigids’
- (There are also fainter Aurids and the Zeta Aurids, but less well-known)
- 3 Messier Objects –
- Messier 36, Messier 37 and Messier 38
There are many different types of Stars in the star system categorized by size, lifespan and luminosity.
Generally, larger Stars have a shorter lifespan.
Stars are formed from clouds of interstellar gas and include:
Red Dwarf Stars
Most of the stars in the galaxy are Red Dwarf Stars. They are small in size measuring about 40-50% of the mass of The Sun. They are cool and their luminosity has only about 10% of the brightness of the Sun (our brightest Star), and they live for longer.
Brown Dwarf Stars
These are known as failed stars that form like other stars but don’t reach the mass, heat or density to begin the nuclear fusion process. They are only about 8% of the mass of the Sun and are red not brown, and not easy to spot in the night sky.
Red Giant Stars
These are giant luminous stars that have a low or medium mass. Red Giant Stars are formed when a star expands its volume by fusing all of its hydrogen into helium, and then burning the helium to produce carbon and oxygen to expand.
These are giant, bright stars that range from 10-100 times the size of the Sun and are 1000 times brighter. They are big and hot and therefore burn out quickly. The biggest are called Blue super giants or hyper giants. The biggest ever discovered was about 10 million times brighter than the Sun,
These are main-sequence stars like the Sun, but only 80% of its size, and are bright stars,
These are small burnt out husks of stars, about the same size as the Earth. White Dwarfs are dense and represent the final state of evolution for a star, like most stars in the galaxy.
These are the remains of a White Dwarf after it cools and darkens. This is likely to happen after about 10 billion years of life.
These are also main-sequence stars like the Sun, but twice the size, and are bright stars and hot.
Other types of stars include Neutron stars, Variable Stars and Binary Stars
What is a Bright Star?
The sky is home to various bright stars.
The brightness of a star is measured by a value called its magnitude (apparent magnitude) and they come in different sizes, composition, mass and color.
Their vast distance away from us is measured in light years from the Earth, the Sun or even the Milky Way.
The lower the magnitude value the brighter the star appears in the night sky when viewed from Earth.
FACT: The Sun is considered to be the brightest star in the sky.
Auriga Constellation is usually identified by locating the bright Star Capella, the asterism known as ‘the kids’ and other stars and star clusters that form the Charioteer outline in the night sky
The Auriga Constellation also has deep sky objects and galaxies (or even globular clusters or open clusters).
Deep Sky Objects
The Constellation of Auriga has a total of 37 deep sky objects, including objects from the Messier New General Catalogue (abbreviated to NGC) and the Index Catalogue (IC):
The 3 Messier objects are:
- Messier 36 (M36, NGC 1960)
- The Messier 37 object (M37, NGC 2099)
- Messier 38 (M38, NGC 1912)
Plus index catalogued objects:
- The ‘Flaming Star Nebula’ – IC 405
- IC 410
- IC 417
FACT: A Deep Sky Object is an astronomical object, that is not a solar system object like the Sun, Moon, Comet or a Planet. An individual Star is not considered to be a Deep Sky Object.
Deep Sky Objects are faint objects that can still be observed by the naked eye in the night sky from Earth.
Deep Sky Objects include Galaxies, Star Clusters and Nebulae.
- Star clusters – such as Globular Clusters of Stars or Open Clusters of Stars
- Dark Nebula, Planetary Nebula, Diffuse Nebula, and Supernova remnants
- Galaxy Groups, Galaxies, Gravitational Lenses and Quasars.
What is a Nebula?
A Nebula is a massive cloud of gas and dust in Space.
Some Nebulae are formed when a star explodes and then dies, as is the case with a Supernova. Sometimes they can act as Star nurseries and are the areas where new Stars are forming.
The Nebulae are the spaces in between the stars referred to as interstellar space.
There are several types of Nebulae:
- Bright Nebulae,
- Emission Nebulae,
- Reflection Nebulae,
- Dark Nebulae
- Planetary Nebulae
FACT: a ‘reflection nebula’ is an interstellar cloud that should be a dark nebula (a molecular cloud) however its dust reflects light from a nearby bright star and it reflects the light, hence the name.
Images of the Nebulae have been captured using professional Space telescopes, such as the NASA Spitzer Space Telescope, operated by NASA, and the famous Hubble Space Telescope.
Auriga is often abbreviated to ‘Auri’ from a naming convention used by NASA.
What is a Messier?
A Messier is a cluster of Stars
There are 3 Messier objects within ConstellationAuriga called M36, M37 and M38.
It was Charles Messier, a French astronomer, who is credited with cataloging each of the Messier Star clusters, around 1764.
He is famous for publishing an astronomical catalogue that lists 110 nebulae and star clusters, known as the New General Catalogue (used in its abbreviated form NGC and numbered).
These later became known as the Messier objects.
FACT: A star cluster is a large group of Stars that can be Globular Clusters or Open Clusters:
- Globular Clusters:
A global cluster is a spherical collection of ‘Old Stars,’ numbering hundreds to millions, that are tightly bound by gravity and orbits a galactic core.
- Open Clusters:
An open Cluster is a looser formation of ‘Young Stars’ that generally has less than a few hundred Stars.
The Messier Marathon
The best time of year to view all 110 Messier objects at the same time, if the night sky conditions are positive, is between mid to late March and early April.
A supernova remnant is the structure that’s left after a star explodes in a supernova.
There are 3 types of supernova remnants:
- Mixed-morphology (or thermal composite).
What is the Milky Way?
The Milky Way is a Spiral Galaxy, containing over 200 billion Stars, and actually forms part of the Constellation of Sagittarius.
The Milky Way itself is not a Constellation of Stars, it is the Galaxy that contains our solar system and it gets its name from the fact that it looks like a hazy swirl or river of milk across the sky, when viewed from earth.
It is made up of gas, dust and stars, with spiral arms wrapped around it, and a massive black hole in the center of the Galaxy.
Not all of the Stars in the Universe are contained within the Milky Way.
It is at its brightest if looking towards the galactic center in the direction of Sagittarius.
The Stars that make up the Milky Way are many light years away and cannot be individually identified by the naked eye.
Background & Facts:
The Greeks were the first ancient culture to name the modern 88 Constellations in the sky.
It was the Greek Astronomer – Ptolemy, who first cataloged the Constellation of Cetus as one of 48 early constellations, in the 2nd Century (2 AD.), and remains as one of the 88 modern Constellations defined by the IAU.
Ptolemy listed the various constellations in his Almagest (a book recording astronomical data).
In 1603, The German Astronomer – Johann Bayer, systematically assigned names to the brightest stars in Auriga and cataloged them in his Star atlas – ‘Uranometria Omnium Asterismorum’. Bayer depicted Auriga as ‘the mythical Charioteers’ such as Erichthonius and Myrtilus’.
The Bayer designations are stellar designations where the stars within Constellations are initially identified by a name or letter from the Greek Alphabet from Alpha through Omega (in descending order of brightness).
The names of the Stars begin with a letter of the Greek alphabet starting with– Alpha, then beta, gamma, delta, epsilon, zeta etc.
Followed by the genitive form of their parent constellation’s Latin name – ‘Auriga ‘with ‘e’, makes the name ‘Aurigae’
Giving the first Star ‘Capella’ the name Alpha Aurigae
The 10 mains tars of Auriga are named by their apparent magnitude (luminosity) in decreasing order:
1. Capella, (Alpha Aurigae) – an apparent visual magnitude of 0.08
2. Menkalinan, from Arabic, (Beta Aurigae) – a variable visual magnitude of 1.85 – 1.95
3. Mahasim, (Theta Aurigae) – an apparent visual magnitude of 2.62
4. Hassaleh, Kabdhilinan from Arabic, (Iota Aurigae) – an apparent visual magnitude of 2.69
5. Almaaz, from Arabic, (Epsilon Aurigae) – an apparent visual magnitude of 3.03
6. Haedus, from Latin, (Eta Aurigae) – an apparent visual magnitude of 3.18
7. Sadatoni, from Arabic, (Zeta Aurigae) – an apparent visual magnitude of 3.69
8. Prajapati, from Sanskrit, (Delta Aurigae) – an apparent visual magnitude of 3.72
9. Nu Aurigae, from Latin, – an apparent visual magnitude of 3.96
10. Pi Aurigae, from Latin, – an apparent visual magnitude of 4.37
The importance of the Constellations such as Auriga dates way back to the times of the Babylonians who identified constellations with bright Stars.
One of the first records of the Stars of Auriga is from Mesopotamia. The Mesopotamians called Auriga, ‘GAM’,‘Gamlum’, ‘MUL.GAM’ or ‘MUL.PIN’, as recorded in the Babylonian astrological catalogue.
The image identified for Auriga was that of a scimitar or a shepherds crook, which is associated with a shepherd or goat herd.
How do the Bright Stars of Auriga form the shape of a Charioteer holding the reins of a Chariot and goats?
The Bright Stars
If you look up and into the night sky you can imagine the recognizable outline of the Constellation of Auriga, which is a large man who drove a Chariot.
Stars with Planets
Auriga has 7 Star with an exoplanets orbiting around it in the solar system but it is unlikely to be able to support life forms.
The furthest exoplanet discovered was actually in the Andromeda Galaxy, not in the Milky Way.
Not all the stars within the Auriga Constellation are visible to the naked eye but with telescopes and modern imagery techniques is it possible to glimpse all of the stars.
FACT: An exoplanet (also referred to as an extrasolar Planet) is a planet that orbits a Star that is not located within our Solar System (exoplanets do not orbit our Sun)
Nothing stands still in the sky.
Planets are continually being discovered and lists updated.
The Constellations change their positions throughout the year as the Earth rotates around the Sun.
This means our position in space is forever changing and as a result our view of what’s in space changes too, and will continue to do so.
What is the purpose of Auriga? –
In ancient times the dots, bright lights and perceived objects in the sky were of great interest and the makings of folklore to a great range of people from seamen to farmers.
From children to the elderly, we have had an ongoing fascination, with our solar system and star system. Perhaps it’s because the enormity and variety within it makes us realize just how large and exciting the universe is.
FACT: The Star System or Stellar System is a small number of stars that orbit around each other and are bound together by gravity.
When it becomes a large group of stars, again bound together in the same way, by gravity, it is known as a Galaxy or Star Cluster.
Whether they contain small groups of stars or larger groups of start the both come under the classification of ‘Star System’.
The Auriga celestial pole
The celestial pole defines the poles of the celestial equatorial coordinate system.
An object at the Celestial pole has a declination of 0 degrees.
- The declinations for the north celestial pole is +90 degrees
- The declinations for the south celestial pole is -90 degrees
The celestial poles are not permanently in a fixed position against the background of the stars as everything moves in Space.
Auriga is located in the northern celestial sky at a +90 degree north and 40 degrees south declination, and an average 6 -hours right ascension.
Navigational tools in the sky
The many Constellations in the night sky were a useful navigation tool and guide as well as the subject of legends and myths.
42 of the Constellations have been named after animals with a story behind each name.
Historical significance: the legends, and myths surrounding Constellation of Auriga
When Ptolemy, the Greek astronomer, catalogued Auriga as far back as the 2nd century, it became a topic of great interest in Greek mythology and in other ancient civilizations.
However the origins of the earliest Constellations probably date back to prehistory.
Many ancient civilizations have related the Constellations in the sky to suit their beliefs and creations itself. They have been the subject of folklore and experiences for a very long time.
There are many Greek myths and legends surrounding the origin and names of the constellations. One myth involves Myrtilus, a divine hero and the son of Hermes. He was the Charioteer of King Oenomaus of Pisa. In those times men raced chariots for the hand in marriage of a beautiful woman.
Myrtilus was asked by Pelops (who was a grandson of Zeus and in love with Hippodamia), on the eve of the challenge to sabotage the race for his master Oenomaus and prevent his chance of winning the hand of Hippodamia. He did in return for the promise of one night with this beautiful woman. When Oenomaus died in the race he cursed Myrtilus, and Pelops killed Myrtilus before he could be with his love and cast him into the sea He was believed to have put a curse on the family of Pelops before his death.
Another Greek myth involves Erichthonius, who was the 4th King of Athens and son of Hephaestus. The goddess Athena raised him and she taught him many things.
He was not able to walk very well but he was creative and built himself a chariot to help his mobility. He invented a four-horse chariot, a Quadriga, which we think of as the traditional image of a chariot and him as the charioteer holding the reins of the four horses.
The image of Auriga shows a strong Charioteer holding a she-goat and her Kid goats in his arms. (The 3 dim Stars in Auriga are often referred to as the Kids).
Zeus was impressed by Erichthonius and placed him in the sky.
Ancient associations with the constellations
The Greeks, the Romans and the Sumerians all had an interest in the constellations in the sky.
The Sumerians were the first literate civilization of the Ancient Mesopotamia (an area occupying parts of Turkey and the Syria of today, Iraq, Iran)
The Sumerian civilization was not unified like the ancient Greek or Roman civilizations it was bonded by a common attitude – Their belief systems featured many deities. They regarded their gods as being responsible for everything and as such held them in great respect. Many stories arose as a result.
For thousands of years, various cultures around the world have identified and named the constellation we know and see in the night sky as Auriga.
The Mesopotamian civilization (the first known civilization) identified constellations like Auriga.
FACT: The ancient lands of the Mesopotamians now stretches across Turkey, Syria, Iraq and Kuwait
Auriga and the other constellations in the sky were not only the subject of legends but they had a practical use too.
The ancient Mesopotamians and in Asia used the orientation of the constellations to set the seasons for sowing crops and harvesting.
The Babylonians also recorded details of various bright stars within the constellations in their Babylonian star catalogues before 100 BCE.
What is the difference between a constellation and an asterism?
An asterism is a group of stars that appear to form a pattern in the night sky but with no officially determined boundaries.
It can make up part of a constellation or cross the boundaries of an official constellation or even a defunct constellation.
An asterism is a more vague assembly of stars than a recognized constellation.
The meteor showers of Auriga
There are 2 annual meteor showers associated with the Constellation of Auriga; they are known as the ‘Aurigids’ and are considered rare due to the lengthy passage of time their parent comet takes to orbit the Sun.
They are visible in the Northern Hemisphere in a Northeasterly direction, late at night
These showers are also visible from the Southern Hemisphere, close to the horizon early in the morning, around 03.00 hours
‘The Aurigids’ meteor showers includes – The Alpha Aurigids (206 aur), The Delta Aurigids, and are best seen between August 28 and September 5, with peak visibility on August 31.
The location is at a right ascension of 6hr 4 minutes, and a declination of +39.
The closest Star to the key point of the Aurigids meteor showers is Capella (alpha aur).
The parent body of the meteor shower associated with the constellation of Auriga is a Comet known as C/1911/ N1 Kiess.
Fun Facts about Constellations – Did you know that?
- The Constellation of Auriga is not one of the 12 constellations of the Zodiac.
- The Brightest Star Capella is also significant in other cultures –
- In Hindu culture it represents the ‘Heart of Brahma’
- The Aztecs people worshipped this bright Star
- In Peru it is known as Colca, the star that looks after shepherds
- The Northern Inuits referred to Auriga as the collar bone in the Constellation, called ‘Quturjuuk’
- In the American indigenous culture in California believed it formed a significant crescent shape
- In ancient China, it called Wuche, and represents the 5 chariots of the celestial emperors, and the harvest.
- Auriga is represented in many cultures as a sign for harvest time and as a navigational guide.
- Auriga is sometimes referred to as a polygon with 21 segments
- There are over 4000 known exoplanets in the night sky, with another 5000 awaiting classification
- The Constellation of Auriga is the 21st largest and occupies around 1.6% of the night sky
- Charles Messier the French Astronomer who cataloged the Messier objects has a crater on the Moon named after him.
- Constellations like Auriga are not part of our Solar System; they are groups of stars that appear to form shapes that are visible with the naked eye from Earth.
- The largest Constellation is called Hydra and the smallest Constellation is called Crux
- A Constellation does not actually exist as a fixed object, it is a group of bright stars that happen to be in a random place and are light years apart and ever moving. We see the pattern of their presence.
- The center of a Galaxy does not contain a Giant Star it contains a massive Black Hole.
- Spiral Galaxies make up about two third of all the Galaxies in the Universe
Commonly Asked Questions
Q. What is the celestial sphere?
A. In astronomy and navigation terms, the celestial sphere is imaginary.
This virtual sphere has a large radius that is concentric with Earth.
We can imagine all objects in the night sky as being projected upon the inside of this celestial sphere, as if it has images placed inside a dome.
Q. What’s the difference between a Constellation and an asterism?
A. The stars that make up a Constellation have a definite position and form, whereas an asterism is a collection of stars without a fixed position
Q. What prevents us seeing the Stars and Constellations in the night sky?
A. Light pollution, fog, city lights and artificial lights all limit our visibility of the objects in the sky at night.
Q. Will the Constellations change over time?
A. The Constellations are continually on the move.
The images we form in our imagination to make objects, shapes and patterns out of the constellations have already shifted over time.
As we view the night skies from Earth they are likely to continue to shift and possibly in time the images may look very different.