The Columba Constellation – Facts in brief:
What is it? –
Columba constellation, also known as the Dove Constellation, is regarded as a fairly small and faint constellation in the Southern Celestial sky.
It is listed as the 54th largest Constellation overall filling around 0.7% of the night sky.
The Constellation Columba is associated with one of the most fascinating Biblical stories: Noah’s Arc and the great flood , including details of Noah’s dove with the olive branch.
The name ‘Columba’ is Latin for the ‘dove’.
Columba, (and Columbae, its Latin genitive) is often abbreviated to ‘Col’, is quite easy to recognize as it resembles the outline of the dove.
Where is it located? –
The Columba Constellation is positioned in the first quadrant of the Southern Hemisphere, south of the ecliptic (which is different from the celestial equator). Being located south of the celestial equator makes it more visible from Northern latitudes in the Southern Hemisphere.
It is sometimes referred to as being located in the SQ1 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 plane of the Milky Way passes close the Constellation of Columba and therefore close to the Stars that previously formed the now renamed Constellation Argo Navis (this Constellation was imagined as the ship and mast area from the Greek myth of Jason and the Argonauts)
The Constellation of Columba is not considered to be a circumpolar constellation as it is not visible throughout the year in Southern latitudes.
It is best seen in the winter months, especially in February.
Circumpolar Constellations
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
- Cepheus Constellation
- Draco Constellation
- Ursa Major Constellation
- Ursa Minor Constellation
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 Columba.
Columba is most prominent in the Southern Hemisphere.
The Constellation of Columba lies at a 6 hours right ascension, and a declination of -35 degrees.
It’s more easily visible from the Southern Hemisphere at latitudes between +45 degrees and -90 degrees and covers an area of 270 square degrees in the Southern sky.
How was it formed, found and named?
The Constellation of Columba is not one of the original 48 Constellations that were devised and later catalogued by Ptolemy.
It was in fact many years later that the Dutch astronomer Petrus Plancius first introduced this constellation to the world in the 16th Century as part of his mapping of the Constellations. He also charted a smaller world map, which included Columba.
Columba also featured on the early Dutch celestial globes and reproduced by many cartographers.
Petrus Plancius created a map of the various celestial Constellations and initially depicted Columba as a group of Stars in the larger Constellation of Canis Major, and initially named it the constellation Columba Noachi.
The constellation name ‘Columba Noachi’ means ‘Noah’s Dove, in reference to the biblical story of Noah’s ark, and the dove that was sent into flight by Noah to see if there was any dry land left after the great flood.
If the dove returned with the olive branch in its mouth it signaled that the great flood was receding.
In 1603, the Constellation of Columba was listed in ‘Uranometria’, the Star Atlas compiled by German astronomer Johann Bayer.
Columba fills an area of 270 square degrees.
- Initially, the shapes of their star patterns informally categorized the Constellations in the sky.
- Eventually, the International Astronomical Union (IAU) published the official listing of constellation boundaries, mapping the constellations by their sky coordinates not by their line patterns and shapes.
Constellation Columba is one of the 88 Constellations within the celestial sphere that is listed in the official IAU chart published by the International Astronomical Union (IAU).
How can you identify The Constellation of Columba?
The simplest method for spotting any particular Constellation from Earth is to first of all locate the brightest star in that Constellation, and then look at the neighboring illuminations, or other neighboring well-known Constellations, to see if you can identify a recognizable pattern.
Columba Constellation: Meet The Neighbors
The Columba Constellation is bordered by several other Constellations:
- Canis Major and Lepus – to the North
- Puppis, Pictor and Caelum – to the South
It is most visible in the Southern Hemisphere in the evening around 21.00 hours, during the month of February.
The Constellation of Columba is located close to the path of the Milky Way.
The Heavenly Waters Family of Constellations
Columba is a member of the ‘Heavenly Waters Family of Constellations’. This group of Constellations includes:
- Carina, Columba, Delphinus, Equuleus, Eridanus, Piscis Austrinus, Puppis, Pyxis and Vela.
The Stars in Columba Constellation
There is 1 bright star (Phact), with a magnitude brighter than +3.0, located within the faint Constellation of Columba.
There are only 5 Stars that make up the main outline of the Columba Constellation, with a total of 18 Stars that have been classified under the Johann Bayer Flamsteed system of naming Stars in the night sky.
The brightest Stars in any Constellation are listed and named in order of luminosity, using the Bayer designation system, from the brightest Star to the faintest Star.
A Bayer designation for a Star is where the ‘Alpha’ letter is normally allocated to the brightest star in front of its Latin genitive name (Columbae), then ‘Beta’ and so on in decreasing order through the letters of the Greek alphabet (although not all the Greek letters are used in every constellation).
Quick Facts:
- In the Constellation of Columba the brightest Star is Phact (an Arabic name), Alpha Columbae, which has an apparent visual magnitude of 2.6, and visible by the naked eye
- The second brightest Star in Columba is called ‘Beta Columbae’
- The 3 main bright Stars are alpha Col, beta Col and delta Col
- The closest Star is Gliese 218 located around 48.89 light years from Earth
- The dimmest Star that can be seen by the naked eye is HD 43847 with an apparent magnitude of around +6.0
- The farthest Star is HIP 43041, and it’s located around 81541 light years from the Sun
- There are 45 Stars in Columba that are visible by the naked eye in a clear dark night sky.
- A total of 806 Stars have been identified and scanned by the Hipparcos satellite but not all are visible by the naked eye.
The Shape
The Columba Constellation can be identified in the night sky, as the dove from the biblical story involving Noah’s dove, where the dove alerted Noah to the fact that the great flood was receding.
While Columba is often connected with this image it is also represented in other stories, such as the dove was sent by Jason’s Argonauts to fly between the clashing rocks to make sure the Argonauts had a safe passage through those rocks by ship.
The bright stars of Columba can be viewed from Earth, from a variety of locations, from a Southern location in the evening, by the naked eye.
The Star System within Columba
There are 3 named Stars within Constellation Columba that are approved by the IAU, each with an Arabic name: Phact, or Phakt (alpha Col), Wezn (beta Col), and Elkurud (Theta Col).
The Constellation Columba has 5 main Stars making up the imaginary outline of the dove
The stars that form the overall shape of Columba are:
- Phact, Alpha Columbae (a Col) – the brightest star in Columba, 268 light years distant
- Wezn, Beta Columbae (b Col) – the second brightest in Columba, 86 light years distant
- Delta Columbae, Ghusn al Zaitun, (y Col) – a binary Star system, 237 light years distant
- Epsilon Columbae (e Col) – a bright Star, 277 light years distant
- Eta Columba (ncol) – a solitary Star, 472 light years from the Sun
- Gamma Columbae (y Col) – a wide Binary System, 853 light years distant
- Kappa Columbae (k Col) – a solitary Star, 183 light years distant
- Omicron Columba (o Col) – a Star, 110 light years distant
- Theta Columba (Elkrund) – a Star, 720 light years from the Sun
- Mu Columba (u Col) – an O-class Star, a runaway Star, 1300 light years from the solar system
Hipparcos created the apparent magnitude system to rank the brightness of Stars (for example he decided that that the grade of a first magnitude star should be twice as bright as a second magnitude Star, and so on.
FACT: The commonly quoted ‘Hipparcos Satellite’ is an abbreviation of ‘The High Precision Parallax Collecting Satellite’, which is an astrometric satellite used by the European Space Agency (ESA)
The Location of Columba Constellation
This Constellation can be spotted in the Southern Hemisphere, also referred to as the Southern celestial sky.
The Constellation Columba is surrounded by various recognizable Constellations namely, Canis Major, Lepus, Puppis and Pictor.
The identifiable outlines of these Constellations are used as a guide-point in the sky used by astronomers and amateur stargazers to identify certain Deep Sky Objects of interest.
The naming of Columba Constellation
Columba is thought of as Noah’s dove.
It was the cartographer and astronomer Petrus Plancius who noted this Dove Constellation from the collection of Stars behind the original old Constellation of Argo Navis (now defunct) associated with the myth of Jason and the Argonauts.
Originally the main Star asterisms in Argo Navis were imagined as parts of the whole ship image:
- Carina represented – the keel or hull of the ship
- Vela represented – the sail of the ship
- Puppis represented – the stern or the poop deck of the ship
Eventually these identified Stars in Argo Navis became known as these independent Constellations.
What’s within the Columba Constellation?
The different components usually housed by Constellations are mainly Stars, Deep Sky Objects and Messier objects (galaxies).
The Constellation of Columba is formed by of a number of different components, it has:
- 5 main Stars
- 3 stars that host an exoplanet
- 3 named Stars
- 0 associated meteor showers
- 0 Messier Objects
The Stars
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. A Red Giant Star is 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.
Blue Giants
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,
Yellow Dwarfs
These are main-sequence stars like the Sun, but only 80% of its size, and are bright stars,
White Dwarfs
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.
Black Dwarfs
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.
White Stars
These are also main-sequence stars like the Sun, but twice the size, and are bright stars and hot.
Other types of stars include the Orange Giant, 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. Locating its brightest Star, alpha Columbae, can identify The Columba Constellation.
As well as Stars and Star Clusters, Columba also has deep sky objects and galaxies (or even globular clusters or open clusters).
Deep Sky Objects
The notable deep sky objects, includes objects from the Henry Draper Catalogue of Stars (abbreviated to HD and a designated number as an identifier)
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, Spiral Galxaies, Gravitational Lenses and Quasars
There are no named Messier objects, but there are Messier NGC catalogued objects present in Columba, such as:
NGC 1808
- NGC 1808 – a Seyfert 2 galaxy, located around 40 million light years distant with an apparent magnitude of 10.8 (not visible by naked eye). It is a barred spiral galaxy, which is similar in many ways to the Milky Way.
NGC 1851
- NGC 1851 – known as Caldwell 73 is a globular cluster, located around 39,500 light years distant with an apparent magnitude of 7.3. This globular cluster is not visible by naked eye)
NGC 1792
- NGC 1792 – another spiral galaxy, and a starburst galaxy that has an apparent magnitude of 10.2. It gives off an orange glow from the center
NGC 2188
- NGC 2188 – is an emission line galaxy, deep sky object, that is not located in the solar system
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.
Columba is often abbreviated to ‘Colm’ from a naming convention used by NASA.
What is a Messier?
A Messier is a cluster of Stars
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).
There are no Messier object star clusters within Constellation Columba, but there are some NGC listed objects, like – NGC 1851 and NGC 1808
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.
Supernova Remnants
A supernova remnant is the structure that’s left after a star explodes in a supernova.
There are 3 types of supernova remnants: shell-like, composite and 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 Constellations in the sky.
However, in the case of the constellation of Columba there were no associated Greek myths, nor did they mention the dove in mythology.
Ptolemy
It was the well-known Greek Astronomer – Ptolemy, who first cataloged the 48 early constellations, in the 2nd Century (2 AD.), but he did not catalogue the Constellation of Columba.
It was the Dutch astronomer Petrus Plancius who first created Columba and it still remains as one of the 88 modern Constellations defined by the IAU.
Bayer
In 1603, The German Astronomer – Johann Bayer, systematically assigned names to the brightest stars in each constellation and cataloged them in his Star Atlas – ‘Uranometria Omnium Asterismorum’.
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 order of brightness).
1. The names of the Stars begin with a letter of the Greek alphabet starting with– Alpha, then beta, gamma, etc.
2. Followed by the genitive form of their parent constellation’s Latin name – ‘Columbae’
3. Giving the first Star name Alpha Columbae
The main stars of Columba are named by their apparent magnitude (luminosity) from the brightest to faintest star in decreasing order, Stars with an apparent magnitude of less than +5.00 include:
1. Alpha Columbae – an apparent visual magnitude of 2.65
2. Beta Columbae – a variable visual magnitude of 3.12
3. Delta Columbae – an apparent visual magnitude of 3.85
4. Epsilon Columbae – an apparent visual magnitude of 3.86
5. Eta Columbae- an apparent visual magnitude of 3.96
6. Gamma Columbae– an apparent visual magnitude of 4.36
7. Kappa Columbae – an apparent visual magnitude of 4.37
8. Omicron Columbae – an apparent visual magnitude of 4.81
9. Lambda Columbae – an apparent visual magnitude of 4.88
10. Xi Columbae – an apparent visual magnitude of 4.97
Plus Mu Columbae, blue Star and a runaway Star, an apparent visual magnitude of 5.18
The importance of the Constellations such as Columba dates way back to the times of the Babylonians who identified constellations with bright Stars.
The Bright Stars of Columba
If you look up and into the night sky you can imagine the recognizable outline of the Constellation of Columba, as a dove.
This main constellation is made up of 45 bright Stars and a total of 806 identified.
Stars with Planets
Columba has 4 Stars with an exoplanet orbiting around it in the solar system but they’re 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 Columba 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 Columba? –
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 Columba 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.
Columba is located in the Southern celestial sky at a +45 degree and -90 degrees 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: surrounding Constellation of Columba
Myths and Stories
The Constellation of Columba is one of the 42 Constellations named after an animal – the dove.
Many ancient civilizations have related the Constellations in the sky to suit their beliefs and creation itself. They have been the subject of folklore and experiences for a very long time.
Columba is not connected with any Greek or Roman myths or gods, however it has been connected with images and associations in other cultures based on stories involving the dove (such as a ring dove or Cape Turtle dove)
However it was previously associated with a neighboring Constellation and it’s story of Jason and the Argonauts – the Constellation of Argo Navis, but this Constellation is now obsolete.
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.
Offering an ‘Olive Branch’ is a phrase used to mean offering peace and the dove (possibly a ring dove) is also associated as the bird of peace.
For thousands of years, various cultures around the world have identified and named the constellation we know and see in the night sky as Columba.
The Mesopotamian civilization (the first known civilization) identified constellations like Columba.
FACT: The ancient lands of the Mesopotamians now stretches across Turkey, Syria, Iraq and Kuwait
Columba and the other constellations in the sky had a practical use.
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 Columba
There are no annual meteor showers associated with the Constellation of Columba
Fun Facts about Constellations – Did you know that?
- The Constellation of Columba is not one of the 12 constellations of the Zodiac, that appear when the Sun sets
- The sky is not divided equally between all the constellations
- Constellations have been represented in many cultures as signs and navigational guides.
- The dove bird comes from the family Columbidae, and includes various species such as the Ring dove, the Cape Turtle dove and the Half-collared dove.
- The rate of formation of stars in a starburst galaxy is more than 10 times faster than the star formation in the Milky Way galaxy
- The dove is also significant in other cultures
- In the ancient Chinese astronomy, the 3 pairs of Stars in Constellation Columba represents 3 generations of a family. Family generations are important within Chinese culture:
- Zhangren, the father, an elderly farmer is represented by – Alpha and Epsilon Columbae
- Zi, the Son is represented by Lambda or Gamma Columbae
- Sun, the Grandson is represented by Delta or Theta
- As the Constellation of Columba is made up of Stars that are in many different locations and vast distances from each other it is now possible to go to just one location to view it. It is visible from many different locations.
- The average distance to the main Stars in the small Southern Constellation Columba is around 264 light years away.
- There are over 4000 known exoplanets in the night sky, with another 5000 awaiting classification
- The scale of a Constellation is measured in square degrees
- The planet Jupiter is often cited when making size comparisons between planets or stars. The Jupiter mass is a unit of mass equal to the total mass of planet Jupiter
- Charles Messier the French Astronomer who cataloged the Messier objects has a crater on the Moon named after him.
- Constellations like Columba 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
- The Sun does not belong to any constellation.
- 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.
- Red Dwarf is not a Dwarf Planet it is a Star. Most common Stars are Red Dwarf (cool Stars)
- 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 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.
Sources:
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