CONSTELLATION FIELD GUIDE: A semester of exploring the night sky.
Created by Madison Smith April 24, 2017
TABLE OF CONTENTS Page 3… Introduction Page 4… Magpie Page 5… Dorado Page 7… Canis Major Page 8… Puppis Page 10… Hydra Page 13… Virgo Page 16… Lupus Page 18… Draco Page 21… Australis Page 23… Indus Page 26… Octans Page 28… Tucana Page 32… Perseus Page 35… References
INTRODUCTION This guide contains information on multiple constellations collected over the course of a semester for astronomy 103. The guide includes photographs of the constellations and deep space objects within them. In addition, there is information about where they lie in the night sky and the mythology behind them, as many were discovered in ancient Greek times. The first constellation was a practice week consisting of a virtually created constellation made and named by myself. Constellations are Earth-based interpretations of twodimensional star patterns in the sky. Stars do not necessarily have to be close to one another in order to be clustered into a constellation, as the luminosity and distance from Earth differs greatly by stars. A constellation can be defined through the boundaries of its sky coordinates according to the IAU. However, constellations have been historically noted by the shapes formed by their star patterns. There are now 88 acknowledged constellations in the sky, over half of which were first noted by the ancient Greeks. It is important to be aware of the night sky and all that is contained in it because space unifies humanity and illustrates how small we are in a huge universe. As Carl Sagan stated in his infamous Pale Blue Dot quote, �The Earth is a very small stage in a vast cosmic arena.�
MY CONSTELLATION: MAGPIE Attached is a screenshot of the constellation Magpie which I created. This is supposed to (somewhat) resemble a bird, more specifically a magpie. Magpies hold importance to me and growing up it was my childhood nickname provided by my mother. I love the cleverness associated with these birds as well as the old nursery rhyme “one for sorrow, two for joy, three for a girl, four for a boy…”. I would place this constellation next to Draco in the Northern sky.
DORADO The second constellation I studied is Dorado. Dorado is translated from Spanish as the ‘dolphinfish.’ It is also referred to as the swordfish constellation or Xipias. This constellation was first published by Johann Bayer in 1603 in his star atlas Uranometria based on the findings from Petrus Plancius, Pieter Dirkszoon Keyser, and Frederick de Houtman. There is no myth associated with this constellation as it was created by Petrus Plancius, a Dutch astronomer, who generally just named the constellations after animals. Dorado is placed in the first quadrant of the Southern hemisphere and can be observed from locations between +20 degrees and –90 degrees. Dorado is the 72nd largest constellation in the sky and belongs to the Johann Bayer family. Neighboring constellations include: Caelum, Horologium, Hydrus and Mensa.
Dorado Constellation, taken from Constellation Guide
Large Magellanic Cloud, taken from Futurism
Dorado contains two known planets and no Messier objects. The brightest star in the constellation, Alpha Doradus, is one of the brightest binary stars we know of. Also contained in this constellation is Beta Doradus, a Cepheid star, and the second brightest star in the constellation. Most significantly, Dorado contains an irregular galaxy near the Milky Way, the Large Magellanic Cloud. Within this galaxy is S Doradus, a hypergiant and one of the brightest stars in the irregular galaxy. It is classified as an irregular galaxy due to its strange appearance which is credited as being due to tidal interactions with the Milky Way as well as the Small Magellanic Cloud. This galaxy is currently experiencing active regions of star formation and contains nearly 700 open clusters, 400 planetary nebular, supergiant and giant stars, and many other additional celestial objects. Other notable objects contained in this constellation is the Tarantula Nebula, which according to Constellation Guide, is the most active and largest forming region of nearby galaxies. There is also the Ghost Head Nebula which got its name from the two white patches which are deemed “the eyes of the ghost.�
CANIS MAJOR The official and common name of the constellation I researched this week is Canis Major. This constellation is directly translated from Latin as “the greater dog” or as “large dog” by some. The constellation is typically drawn as a dog on its hind legs hunting another animal (symbolized through the Lepus constellation). Canis Major was first recorded in 2nd century CE by famous GreekEgyptian astronomer Ptolemy. Greek mythology regards this constellation as the dog chasing the hunter (Orion). The story behind it is that Canis Major is representative of Laelaps, the fastest dog in the world. Zues is said to have gifted Laelaps and a javelin to Europa, wife of Cephalus. One day Cephalus was hunting with the javelin and accidentally killed Europa and, in the aftermath, left for Thebes with Laelaps. There lived a fox whom was equally as fast as the dog and causing mischief in the province so Cephalus sends Laelaps to hunt him. The chase was never ending so Zues decided to turn both animals to stone and casted Laelaps in the sky as the constellation Canis Major. Canis Major possesses the brightest star in the sky, Sirius, which also happens to be the fifth closest star system to the sun. Sirius has played a large role going way back to ancient Egyptian times as the appearance of this star aided them in creating their calendar and knowing when the Nile would flood. Canis Major also contains the 24th brightest star in the sky, Adhara. Additionally, the constellation also homes the Canis Major Dwarf Galaxy, which is apparently the closest galaxy to the solar system. According to Constellation Guide, Canis Major can be seen in locations +60 degrees and -90 degrees. The constellation is placed in the Southern hemisphere in the second quadrant and is close to Columba, Lepus, Monoceros, and Puppis galaxies.
PUPPIS This week, I had chosen to research the constellation Puppis. That is its official name, although it is abbreviated as pup, and can be translated as ‘the stern’. Puppis belongs to the Heavenly Waters constellation family alongside Pisces, Carina, etc. Part of the mythology associated with Puppis is that it represents one of the three constellations which make up Argo Navis, a compilation of constellations that form one, and used in Greek mythology to represent a great ship. This ship is used in folklore by Jason and the Argonauts to sail and retrieve the golden fleece. Puppis was first noted by Ptolomy in the second century. Then it was later divided into smaller constellations in 1752 by Nicolas Louis de Lacaille.
Puppis Constellation, taken from Constellation Guide
Puppis can be seen in the Southern Hemisphere in the second quadrant and can be observed at locations -90 degrees and +40 degrees. Constellations nearby include Canis Major, Carina, Hydra, and Vila. This constellation is known for having three Messier objects (objects which were famously catalogued by French astronomer Charles Messier): open clusters M46, M47, and a planetary nebulae called the Skull and Crossbones Nebulae. Notable stars present in the constellation such Naos, which is the brightest star in the constellation. Skull and Crossbones Nebula, taken from Wikipedia
HYDRA Hydra is directly translated as the water snake. Hydra was first noted by Ptolemy in the second century. This is the largest known constellation in the sky and is located in the second quadrant of the Southern hemisphere. According to Constellation Guide, Hydra can be observed from latitudes 54 degrees and -83 degrees. Neighboring constellations are Cancer, Centaurus, Virgo, Puppis, Canis Minor, and Libra.
Hydra is rich in mythology. First, it is associated with a Greek adaptation of Babylonian constellations which represented a figure that was part serpent, bird, and lion. Second, and most frequently, this constellation is associated with Heracles’ Twelve Labours mythology as symbolizing a nine-headed monster with only one immortal head. The monster pillaged the town of Lerna, where Heracles battled and eventually killed the monster (also simultaneously contributing to the creation of the constellation Cancer). Other mythology refers to Hydra as a sea monster which caused a crow’s tardiness from bringing one of the Gods water.
Ghost of Jupiter, taken from Constellation Guide
Some important cosmic objects in this constellation include stars, Messier objects, and galaxy clusters. Some significant stars include Alphard, the brightest star in the constellation, V Hydrae, a carbon star that is one of the reddest visible stars in the sky, and Minchir, an orange giant. Other objects include Messier 48 (open star cluster), Messier 68 (globular cluster), and Messier 83 (Southern Pinwheel Galaxy). This constellation also includes Hydra Cluster which is a galaxy cluster with a relatively high amount of dark matter. One last interesting object this constellation has is the ‘Ghost of Jupiter.’ This is a planetary nebula first discovered by William Herschel in the 1700’s and is known for its relative ease in being observed, even by amateur telescopes. Since this is such a massive galaxy there is a plethora of fascinating cosmic objects to study and observe.
VIRGO
The Eyes Galaxy, taken from Constellation Guide
This week’s constellation I researched is Virgo. Virgo is translated as virgin from Latin. Virgo is one of the zodiac constellations first noted by Ptolemy and is the second largest constellation in the sky. The mythology behind the Virgo constellation is that it is typically referenced with Dike, the Greek goddess of justice. According to legend, Dike was put on Earth to rule over justice in the Golden Age of humanity. When Zues took power, however, human kind was no longer as prosperous and the Silver Age began. Dike warned humanity of the danger of forfeiting old traditions of honoring the Gods, but they ignored her so she fled to the hills. Once the Bronze and Iron Ages began, and humans began warring with each other, Dike left Earth for the heavens. Virgo is also associated with the Syrian goddess of fertility and Demeter of Atargatis. Virgo is in the third quadrant in the Southern sky and occupies an area of 1294 square degrees. This constellation can be observed at latitudes between -80 degrees and +80 degrees. Virgo is neighbor to Bootes, Coma, Corvus, Hydra, Leo, Libra, and Crater.
Some significant objects in Virgo include 11 Messier objects: M49, M59, M59, M60, M61, M84, M86, M87, M89, M90, and M104. This constellation also has twenty planets with known planets. Notable meteor showers within this constellation are the Virginids and the Mu Virginids. This constellation also contains the autumn equinox point. Virgo is typically depicted by a goddess with wings holding wheat, which is represented by the star Spica. This is the 15th brightest star in the sky and is classified as a blue giant. The name ‘Spica’ directly translates to “Virgo’s ear of grain.” According to Constellation Guide, Spica is one of the “nearest massive double stars to the solar system.” This star is also notable for most likely guiding Hipparchus to discover the precession of the equinoxes. Since Virgo is the second largest constellation, it contains a lot of celestial objects. Some additional notable objects are: Eyes Galaxies, the Siamese Twins and quasar 3C 273. 3C 273 is the first quasar to ever be identified and is one of the first sources of x-ray found in 1970. This quasar is very compact with a supermassive black hole at the center.
Messier58, Taken from Constellation Guide
Sombrero Galaxy, taken from Constellation Guide
LUPUS
Lupus is translated as “the wolf” from Latin. Like many other constellations, Lupus was first noted by Ptolemy in the 2nd century, yet it does not have any specific myths associated with it. However, the stars now associated Lupus used to be part of the Centaurus constellation. These constellations together symbolized a sacrificed animal held by a centaur. This constellation was also apparently noticed by the Greeks who named it Therium, as well as the Romans who referred to it as Bestia. All that being said, the application of the wolf association to the constellation was not placed until Renaissance times when Ptolemy’s work was being translated. Lupus is the 46th largest constellation in size and can be found in the third quadrant of the Southern hemisphere in close proximity to other constellations such as Scorpius, Hydra, Libra, and Centaurus. This constellation can be observed at locations between +35 degrees and –90 degrees. Lupus is part of the Hercules family of constellations and contains many deep space objects including two stars with known planets.
Artists rendition of SN-1006, taken from Constellation Guide.
The brightest star in this constellation is Alpha Lupi, a blue-white giant star, that has a visual magnitude of 2.30. This star is ten times the size of our Sun and apparently 25,000 times more luminous. The second brightest star in the constellation is Beta Lupi and has a visual magnitude of 2.68. This star possesses around 8 solar masses. Lupus also contains Nu Lupi, a designation between two stars (Nu 1 Lupi and Nu-2 Lupi). This received a lot of attention in 2011 as astronomers discovered three planets orbiting Nu-2 Lupi. What was interesting about this is that the outermost and innermost planets were classified as Super-Earths. Additionally, Lupus contains SN-1006. This is a notorious supernova was the brightest recorded solar event which was witnessed on May 1st globally in the year 1006. In 1965 astronomers were able to locate remnants of the supernova which suggested this event was due to the collision and merging of two white dwarf stars.
DRACO This constellation is one of the largest in the sky and was first noted by Ptolemy in the second century. In addition, it is a circumpolar constellation, meaning it never sets below the horizon for many observers in the Northern hemisphere. Draco is included in the Ursa Major family. Draco is the eighth largest constellation in the sky. It is placed in the third quadrant in the Northern hemisphere and can be viewed from observers at locations at +90 degrees and -15 degrees. This constellation is surrounding others including Bootes, Hercules, Lyra, Ursa Major, and Ursa Minor.
There are many myths associated with this constellation, most notably being associated as one of the 12 labours of Heracles (Hercules). In this myth, Draco represents a dragon that is guarding golden apples in the Hesperides gardens. This apple tree was gifted to Hera upon her marriage to Zues and she placed the dragon there to protect from any apples getting plucked. In some myths, Ladon has 100 heads and in others, he was the offspring of Ceto and Phocys. In contrast, Roman mythology regarded Draco as a Giant Titan who battled with Olympian gods for ten years and eventually was killed by Minerva and thrown into the sky.
Abell 2218, taken from Constellation Guide
Tadpole Galaxy, taken from Constellation Guide
There are many stars and deep space objects associated with this constellation. The brightest star, Etamin (or Gamma Draconis), is an evolved giant that is translated as the great serpent. It may also be referred to as the Zenith Star because it lies so closely to the Zenith point in London. It has an apparent magnitude of 2.3617 and is 471 times more luminous than the Sun. The second brightest star in the sky is Eta Draconis and is only 92.1 light years away from our Solar System. It is approximately 550 million years old and is 60 times more luminous than the Sun. The thirs brightest star, Rastaban, is a massive star that is 40 times the radius of the Sun. It is a binary system due to its companioned dwarf star. Some deep space objects include Abell 2218, which is a galaxy cluster about 2.345 million light years away. It reportedly possesses thousands of galaxies and “a mass equal to 10,000 galaxies.� This object is significant because it was often used as a gravitational lens to find a 13-billion-year old galaxy. In addition, Draco contains the Tadpole Galaxy. This galaxy is a disrupted barred spiral galaxy with a visual magnitude of 14.4. This can be easily spotted due to its recognizable shape that is credited to its long line of trailing stars. Astronomers believe that he disrupted shape is due to a gravitational interaction with another galaxy which grabbed and pulled the stars in a different direction.
AUSTRALIS Australis is a relatively small constellation first noted by Ptolemy in the second century. There is no myth associated with this constellation specifically, however, it is said to symbolize the crown of the centaur (Sagittarius). Before Ptolemy catalogued this constellation, it was referred to as a wreath by the Greeks. This constellation is in fact one of the smallest in the sky only covering an area of roughly 128 square miles. It is in the third quadrant of the Southern hemisphere and can be observed from locations at +40 degrees and -90 degrees. Australis is between Scorpius and Sagittarius and neighboring others like Ara and Telescopium.
Again, Australis is a very faint constellation and has no stars with a magnitude brighter than 3.00. The brightest star in the constellation is Alpha Coronae Australis which is also referred to as Alphekka South. In fact this is the only named star in the constellation Some additional deep space objects include the Corona Australis Nebula. It is a bright reflection nebula roughly 420 light years away and was first discovered by German astronomer Johann Friedrich Schmidt in 1861. This is an active star forming region with a cluster of young stars contained in it. There is also a NGC 6726/NGC 6727, a reflection nebula contained in this constellation. In addition, the Australis constellations contains the Coronet cluster as well. This cluster resides in the heart of the constellation and is one of the nearest regions of active star formation.
Corona Australis Nebula, taken from Constellation Guide
Coronet Cluster, taken from Constellation Guide
INDUS
The Indus constellation is observed in the Southern hemisphere and is known for not containing any bright stars. This constellation is supposed to symbolize ‘the Indian’, but it is unclear what group of indigenous peoples this constellation is meant to represent. Indus was first catalogued in the 16th century by Petrus Plancias, and was first published in Johann Bayer’s Uranometria star atlas. Thus, this constellation is classified as belonging to the Johann Bayer family of constellations, which also includes Dorado, Hydrus, and Pavo. There are no myths associated with Indus. The Indian this constellation represents is typically illustrated with wielding an arrow or a spear in the act of hunting. While it is mostly unclear the people this constellation is meant to represent, Constellation Guide discusses that drawings from Uranometria may suggest a Madagascar native is being represented. Indus is located in the fourth quadrant of the Southern hemisphere and can be observed at locations between latitudes +15 degrees and -90 degrees. This constellation is the 49th in its size and is near constellations Pavo, Sagittarius, and Tucana. Indus contains two stars with known planets and there are no known meteor showers that are associated with this constellation.
NGC 7049, taken from Constellation Guide
NGC 7090, taken from Constellation Guide
Some of the objects contained in Indus include Alpha Indi (‘The Persian’), a star in this constellation that is estimated to be around a billion years old. This star is two times the mass of the Sun and has a pair of red dwarf companions. Additional stars in Indus is Beta Indi, a red giant, and Epsilon Indi, a dwarf star that is only 11.83 light years away from Earth. Epsilon Indi is typically depicted as being one of the arrow points in the constellation drawings. Indus does not contain bright stars, but it contains many notable deep space objects including NGC 7049. This galaxy is roughly 100 million light years from Earth and is known for its expansive outer dust ring. The unique appearance is credited to relatively recent collisions with nearby galaxies. Indus also contains NGC 7090, a spiral galaxy, roughly 30 million light years away, which was not discovered until 1834. In addition, Indus is currently home to the irregular galaxy IC 5152. First discovered in 1908, this galaxy is difficult observe due to a bright star in the foreground.
OCTANS This week’s COW is observing the constellation Octans. It’s placed in the Southern sky and is named after a navigational instrument, the octant. This constellation was first noted in the 18th century by Nicolas de Lacaille. Octans serves as the current location of the Southern Celestial Pole and is circumpolar, meaning it does not set below the horizon. There are no myths associated with Octans, but it was originally named after Octans Hadleianus, who created the octant in the 1700’s. When Lacaille created the constellation, he actually moved stars from Hydrus into Octant.
This constellation is in the fourth quadrant of the Southern hemisphere and can be observed in locations between +0 degrees and -90 degrees. Nearby constellations include Hydrus, Indus, Mensa, and Pavo. Octans does not contain a star with a magnitude brighter than 4, but it does have two stars with known planets. Nu Octanis is the brightest star in the Octana constellation with a magnitude of 3.76. This star is classified as an orange giant but is one of the least luminous known giant stars. However, it is speculated that it will continue to expand and eventually be 15 times the size it is currently. Also, it has a binary companion that is 2.55 AU’s away. There is additional speculation that Nu Octanis has a planet that is believed to have 2.5 times the mass of Jupiter. Octana also contains Beta Octanis, which is the second brightest star in the constellation. Lastly, the other star with a known planet orbiting it is HD 142022.
TUCANA
This week’s constellation is Tucana. As the name suggests, it is named after the toucan, but is not associated with any myths. Petrus Plancius first noted the existence of this constellation from the sightings of sailors Frederick de Houtman and Pieter Dirkszoon. Finally, in 1603, the constellation was legitimized and published in Johann Bayer’s Uranometria. Petrus Plancius was responsible for naming the constellation after the tropical bird, and Johann Bayer decided to keep the name in publishing his atlas. Tucana is in the first quadrant of the Southern sky and is the 48th largest constellation in the sky. It can be observed at latitudes between +25 degrees and -90 degrees. It’s neighboring constellations are Hydrus, Indus, and Phoenix. Tucana does not contain any Messier objects but it does have three stars with known planets. Tucana is also part of the Johann Bayer family of constellations alongside Dorado, Hydrus, Indus, Phoenix, and Volans.
Tucana is home to Alpha Tucanae, which is the brightest star in the constellation. It is a spectroscopic binary system and the primary star is an orange giant. The second brightest star of the constellation, Gamma Tucanae, has a visual magnitude of 3.99 and is 1.55 times larger than the Sun. Tucana is also home to many deep space objects including the Tucana Dwarf. The Tucana Dwarf is a dwarf galaxy discovered by R.J. Lavery in 1990 and is unique because it does not have any star forming activity occurring. In addition, this constellation contains another dwarf galaxy referred to as the Small Magellanic Cloud. This dwarf galaxy contains millions of stars, is a companion galaxy to the Milky Way, and is one of the deep space objects that are observable from Earth with binoculars. It is speculated that the Small Magellanic Cloud was once a barred spiral galaxy (due to its central bar structure) but that it was interrupted by influence from the Milky Way. This galaxy is bonded with the Large Magellanic Cloud, located in the Dorado and Mensa constellations, and there is a ‘bridge’ of gas between the two galaxies which suggests that they have been bound together gravitationally for a long period of time and also that they are tidally interacting.
Small Magellanic Cloud, taken from Earth Sky
Tucana Dwarf, taken from Constellation Guide
PERSEUS
The final constellation studied was Perseus. This constellation was first noted by Ptolemy in the second century and is best known for the Perseid meteor shower. Perseus lies in first quadrant in the Northern hemisphere and is the 24th largest constellation in the sky. This constellation can be observed at locations with latitudes +90 degrees and -35 degrees. Neighboring constellations include Andromeda, Aries, Cassiopeia, and Taurus. Perseus is part of a grouping of constellations illustrating the Greek mythology of the hero Perseus. According to mythology, Perseus was the son of Danae, who is the daughter of King Acrisius. King Acrisius, through an oracle, was told his death would come at the hands of his grandson, so when Perseus was born, he locked both Danae and Perseus in a chest and cast them out to sea. The mother and son ended up on the shore of the island of Seriphos, where the king attempted to wed Danae. Due to Perseus’s objection, the king conjured a plan to rid the island of him by sending him on a quest to defeat Medusa. Perseus prevailed with the help of objects given to him by the other Gods. He saved Andromeda on his way home who became his wife and they lie next to each other in the sky. Her parents Cepheus and Cassiopeia are also neighboring constellations. The Perseus constellation illustrates the hero holding the head of Medusa in one hand and his jeweled sword in the other.
Perseus contains Alpha Persei (Mirfak), one of the brightest stars in the sky and the brightest star in the constellation. When observed north of New York City, Mirfak never sets under the horizon, meaning it is circumpolar. Mirfak is contained in the Alpha Persei Cluster which can be seen with the aid of only binoculars due to its luminosity. Another significant star in Perseus is Beta Persei (Algol). Algol, also called the Demon Star, was the first eclipsing binary star to be discovered as well as the first discovered variable star. The discovery of this star helped destroy the belief that a star’s rate of evolution relies on their mass. Nova Persei 1901, or GK Nova, was a rather bright nova observed in 1901. Prior to Nova Aquilae in 1918, Nova Persei was the brightest nova of modern times. Over time, GK Persei, faded to a magnitude of 12 or 13 with regular outbursts over the past thirty or so years. According to Constellation Guide, these outbursts resemble a “dwarf nova-type cataclysmic variable star,� rather than a typical nova.
GK Nova, taken from Chandra.Harvard.edu
REFERENCES
http://www.absoluteaxarquia.com/nightsky/dorado.html https://futurism.com/the-large-magellanic-cloud/ http://www.constellation-guide.com/constellation-list/dorado-constellation/ Christoforou, P. (2016, December 15). Interesting Facts About The Constellation Canis Major. Retrieved January 31, 2017, from http://www.astronomytrek.com/interesting-factsabout-the-constellation-canis-major/ Constellation Guide. (n.d.). Retrieved January 31, 2017, from http://www.constellation-guide.com/constellation-list/canis-major-constellation/ Plotner, T. (2016, December 16). The Canis Major Constellation. Retrieved January 31, 2017, from http://www.universetoday.com/19780/canis-major-constellation/ http://www.constellation-guide.com/constellation-list/puppis-constellation/ http://www.topastronomer.com/StarCharts/Constellations/Puppis.php https://en.wikipedia.org/wiki/NGC_2467 http://www.constellation-guide.com/constellation-list/hydra-constellation/ https://en.wikipedia.org/wiki/Hydra_(constellation) https://astrobob.areavoices.com/2015/03/25/how-to-find-hydra-the-largest-constellation-in-the-sky/ http://www.constellation-guide.com/constellation-list/virgo-constellation/ https://en.wikipedia.org/wiki/Virgo_(constellation) http://www.solarsystemquick.com/universe/virgo-constellation.htm http://www.constellationsofwords.com/Constellations/Lupus.htm http://www.topastronomer.com/StarCharts/Constellations/Lupus.php http://www.constellation-guide.com/constellation-list/lupus-constellation/ https://en.wikipedia.org/wiki/Draco_(constellation) http://www.space.com/16755-draco-constellation.html http://www.constellation-guide.com/constellation-list/draco-constellation/ https://en.wikipedia.org/wiki/Corona_Australis https://en.wikipedia.org/wiki/Corona_Australis http://www.constellation-guide.com/constellation-list/corona-australis-constellation/ http://www.constellationsofwords.com/Constellations/Indus.htm http://www.constellation-guide.com/constellation-list/indus-constellation/ http://www.constellation-guide.com/constellation-list/octans-constellation/ http://www.ianridpath.com/startales/octans.htm https://en.wikipedia.org/wiki/Octans http://www.eso.org/public/outreach/eduoff/aol/market/collaboration/luneclipse/eclipse97.html http://www.constellation-guide.com/constellation-list/tucana-constellation/ https://www.davidmalin.com/fujii/source/Tuc.html https://www.pinterest.com/pin/102245854015507294/ http://earthsky.org/clusters-nebulae-galaxies/the-small-magellanic-cloud http://www.constellation-guide.com/constellation-list/perseus-constellation/ https://en.wikipedia.org/wiki/Perseus_(constellation) http://earthsky.org/constellations/cassiopeia-and-perseus-in-northeast-on-october-evenings http://chandra.harvard.edu/photo/2015/gkper/