ASTRONOMY FIELD GUIDE

A Constellation for

Every Month

Iris Fontana

PWSCC

Professor Michelle Cullen

Astronomy 103

November 24, 2014

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Table of Contents

January

Mensa………………………………………………...3

February

Monoceros………………………………………...…4

March

Carina………………………………………….…….5

April

Ursa Major………………………………………..…6

May

Centaurus………………………………………..…..7

June

Libra………………………………………..……….8

July

Scorpius………………………………………..……9

August

Sagittarius………………………………………...…10

September

Cygnus………………………………………..…….11

October

Cepheus……………………………………….…….12

November

Cassiopeia……………………………………….….13

December

Fornax………………………………………..……..14

References

………………………………………..…………….15

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January Mensa

Mensa is the official name of the constellation

that was once known as “Montagne de la Table,”

created by the French astronomer Nicolas Louis de

Lacaille. There is no related mythology to Mensa, as it

was named in commemoration of Mount Table, near

Cape Town, South Africa, where Lacaille spent much

time cataloging stars and constellations. “Mensa” is

simply the Latin word for “table.”

Mid-January is the best time to view Mensa, at

9pm the declination of the constellation borders

reaches from -85° to -49°. It is the second-most

southern of the 88 constellations and is located in the

first quadrant of the Southern Hemisphere (SQ1).

Mensa cannot be seen in the Northern Hemisphere, but

can be seen between the latitudes of 4° and -90°.

Mensa is located near the neighbor

constellations of Chamaelon, Dorado, Hydrus, Octans,

and Volans. Mensa is so small that it only holds two

stars with known planets. Its brightest star is called Alpha Mensae, which has a relatively low apparent

magnitude of 5.09.

Mensa is special because although it is one of the smallest constellations, it contains part of the Large

Magellanic Cloud, a galaxy very close to our Milky Way, which can be seen with the naked eye. This is also

how one could easily locate Mensa: through the position of the Large Magellanic Cloud.

Star Chart of Mensa.

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February Monoceros

Monoceros means “the

unicorn” in Latin, and the

constellation is meant to represent the

same mythical creature. It was created

by the Dutch astronomer and

cartographer Petrus Plancius in the

17th century. Plancius originally

named it “Monoceros Unicornis,” as

an attempt to fill the gap between

Orion and Hydra, left behind by the

ancient Greeks. Although there is no

particular myth associated with this

constellation, Plancius was motivated

by the unicorn’s multiple appearances

in the Old Testament of the Bible.

Monoceros is located in the

second quadrant of the northern

hemisphere (NQ2) and is seen between latitudes +75° and -90°. The constellations that border Monoceros

include Canis Major, Canis Minor, Gemini, Hydra, Lepus, Orion, and Puppis. In order to see Monoceros in the

sky, one might locate the area between Hydra and Orion, above the bright star Sirius and below the bright star

Procyon. Monoceros’ position in the sky for February at 9pm will be right ascension 7 hours and declination -

5.74°.

Within Monoceros there lies a Messier object, an open cluster called Messier 50 (NGC 2323), which has

16 stars with known planets. Monoceros’ brightest star is called Beta Monocerotis, and its apparent visual

magnitude is 3.76. Monoceros also hosts two meteor showers, December Monocerids and Alpha Monocerids.

Monoceros is blessed with many interesting deep sky objects, including things like Messier 50, Red

Rectangle Nebula, Butterfly Nebula, open cluster NGC 2254, open cluster NGC 2244 surrounded by the

Rosette Nebula, the Seagull Nebula, and the Christmas Tree Cluster with the Cone Nebula inside it.

Photographs of the later three objects have been included.

Star map of Monoceros.

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March Carina

The constellation Carina was once part of the ancient Greek constellation Argo Navis created by

Ptolemy. The word “carina” means the “keel” of a ship, or rather the spine of the great ship Argo, sailed by

Jason of the Argonauts who searched for the Golden Fleece. Argo Navis was divided into three separate

constellations in the 1700s by the astronomer Nicolas Louis de Lacaille. The other two parts of this ship are

now called Puppis, the poop deck, and Vela, the sails of the ship.

Carina can be seen during the month of March at 9pm in the second quadrant of the southern hemisphere

(SQ2), and is located between the latitudes of 20° and -90°. The best way to find Carina in the night sky is to

locate its brightest star, Canopus (Alpha Carinae), which marks the end of Carina’s ship outline. However,

Carina cannot be observed from the higher northern latitudes, so Alaskans won’t be able to spot it. The many

constellations that border Carina are Centaurus, Chamaeleon, Musca, Pictor, Puppis, Vela, and Volans.

The bright star Canopus is the second brightest star in the sky, the first being Sirius. Canopus was named

after the ship navigator for King Menelaus of Sparta. Carina’s tail end is distinctly marked by Canopus, which

is a white supergiant at -0.72 apparent magnitude. Carina holds many interesting celestial objects, with much of

them housed in the Carina Nebula alone. The Carina Nebula is about four times larger than the Orion Nebula,

but less well known because of its location in the Southern Hemisphere. One of many objects, the Mystic

Mountain is a cluster of pillars of gas and dust inside the Carina nebula, which look like a mountain top

surrounded by clouds.

Star Map of Carina:

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April Ursa Major

The constellation Ursa Major was created by the Greek Astronomer Ptolemy in the 2nd century. The

words “ursa major” simply mean “great bear,” as this constellation is meant to represent the Greek legend of the

bear Callisto. According to Greek mythology, Callisto was once a beautiful nymph who swore a vow of chastity

to the goddess Artemis. Callisto was then seduced by Zeus who gave her a son named Arcas. Artemis punished

Callisto by banishing her, but Zeus’ wife Hera was so jealous she decided to force Callisto to live out her life as

a bear.

Ursa Major is the third largest constellation, taking up an area of 1280 square degrees in the sky. Ursa

Major’s position in the night sky during April at 9pm is in the second quadrant of the Northern Hemisphere

(NQ2). It is best viewed from latitudes between 90° and -30°. The neighboring constellations are Bootes,

Camelopardalis, Canes Venatici, Coma Berenices, Draco, Leo, Leo Minor, and Lynx.

The most important and prominent stars in Ursa Major make up the famous Big Dipper. The Big Dipper

is made of seven stars, all of 2nd magnitude except for Ursae Majoris, which has an apparent visual magnitude

of 1.79. The Big Dipper is an important Northern Hemisphere navigational tool as its star Ursae Majoris points

toward Polaris, the North Star.

There are seven Messier objects located in Ursa Major, including the Owl Nebula (M97), the barred

spiral galaxies of M108 and M109, the Cigar Galaxy (M82), Bode’s Galaxy (M81), the Pinwheel Galaxy

(M101), and the Interacting Galaxies NGC 3690.

Star Map of Ursa Major.

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May Centaurus

The constellation Centaurus was created in the 2nd century by the Greek astronomer Ptolemy. “Centaurus”

means centaur in Greek, and is likely meant to represent the half-titan Chiron, the mythological centaur son of

Cronus, who went on to become the gatekeeper of Olympus. Chiron also mentored many ancient Greek heroes,

including Achilles, Jason of the Argonauts, and Heracles, to name a few.

Centaurus is located in the third quadrant of the Southern Hemisphere (SQ3), and can only be seen in

latitudes between 25° and -90°. The best way to find this constellation is to locate its brightest stars, Alpha

Centauri and Beta Centauri. The constellations that border Centaurus are Antila, Carina, Circinus, Crux, Hydra,

Libra, Lupus, Musca, and Vela.

The most notable stars in Centaurus are Alpha Centauri at an apparent magnitude of -0.27 is the 4th

brightest star, and Beta Centauri at an apparent magnitude of 0.6 is the tenth brightest star in the sky. Centaurus

has many interesting deep sky objects. Among them are NGC 5128, a collision galaxy, NGC 3918, a blue

planetary nebula, NGC 4622 the golden spiral galaxy, and NGC 4650A, a polar-ring galaxy.

Star Map of Centaurus.

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June Libra

The constellation Libra was named by the Greek astronomer Ptolemy in the 2nd century. The word “libra”

means “the weighing scales” in Latin, and is shown as a scale held by the Greek goddess of justice, Dike, who

is represented by the Virgo constellation. Libra was made when people in ancient times noticed that the sun was

directly in Libra during the autumnal equinox, which to them meant the “equal balance of justice.” It is the only

constellation that represents an object from mythology, rather than a person or animal.

Libra is located in the third quadrant of the Southern Hemisphere (SQ3), and can be seen between

latitudes 65° and -90°. The constellations that border Libra are Centaurus, Hydra, Lupus, Ophiuchus, Scorpius,

Serpens Caput, and Virgo. The best way to find Libra in the night sky is to locate the bright star in Scorpius,

Antares, and Virgo’s bright star, Aurora, then look at the area between them.

There are no messier objects located in Libra, but there are many visible stars. Most notably, Beta Librae

(Zubeneschamali) is the brightest star in the constellation with an apparent magnitude of 2.61, and the

classification of blue-white dwarf.

Libra only contains four deep sky objects. NGC 5792 is a barred spiral galaxy with the very faint visual

magnitude of 12.1. NGC 5890 is an unbarred lenticular galaxy with a visual magnitude of 14. NGC 5897 is

Libra’s only globular cluster, 40,000 light years from our sun, with an integrated magnitude of 9. Lastly, NGC

5885 is a distant barred spiral galaxy with an apparent visual magnitude of 11.8.

Star chart of Libra.

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July Scorpius

The constellation Scorpius, sometimes called Scorpio, was created by the Greek astronomer Ptolemy in

the 2nd century. The word “scorpius” literally means “scorpion,” but originally meant “creature with a burning

sting.” Scorpius was the one beast that could defeat the mighty hunter, Orion, so Zeus was pleased with the

animal and sent him to heaven as a constellation. Scorpius is one of the 13 Zodiac constellations on the celestial

equator.

Scorpius can be seen during the month of July at 9pm in the third quadrant of the southern hemisphere

(SQ3), and is located between the latitudes of 40° and -90°. The best way to find Scorpius in the night sky is to

look for the Milky Way, then locate its brightest star Antares (Alpha Scorpii) low on the horizon, which is the

breast of the scorpion. The constellations that border Scorpius are Ara, Corona Australis, Libra, Lupus, Norma,

Ophiuchus, and Sagittarius.

The constellation Scorpius has 13 stars with known planets, and four Messier objects. Messier 6 is a

beautiful nebula called the Butterfly Nebula, and Messier 7 is the Ptolemy Cluster. The brightest star Antares

has an apparent visual magnitude of 0.96, and is 550 light years from our Sun. The Cat’s Paw Nebula (NGC

6334) is an emission nebula with a vast star-forming region and some of the most massive stars known in the

Milky Way.

Star Map of Scorpius.

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August Sagittarius

The constellation Sagittarius was created by Ptolemy in the 2nd century, and means “archer” in Latin.

Sagittarius is usually depicted as a centaur archer aiming a bow and arrow at the heart of Scorpius. Ptolemy

meant the constellation as a tribute to the half-man, half-horse centaur creature of Greek mythology.

Sagittarius lies along the celestial equator in the Milky Way, between Scorpius and Capricornus, as it is

one of the 13 constellations of the zodiac. It is located in the fourth quadrant of the southern hemisphere (SQ4),

and can be seen at the latitudes between 55 and -90. Sagittarius is bordered by many constellations, including

Aquila, Capricornus, Corona Australis, Indus, Microscopium, Ophiuchus, Scutum, Scorpius, Serpens, Cauda,

and Telescopium.

Sagittarius contains a massive 22 stars with confirmed planets. The brightest star is Kaus Australis

(Epsilon Sagittarii) with an apparent visual magnitude of 1.79. There are also 15 Messier objects in Sagittarius,

including the beautiful Lagoon Nebula, Trifid Nebula, and the Omega Nebula.

Star map of Sagittarius (between Capricorn and Scorpio).

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September Cygnus

The constellation

Cygnus stands for “the

swan” in Latin, and was

created by Ptolemy in the

2nd century. Cygnus was

meant to represent the

Spartan Queen Leda of

Greek Mythology, who

was seduced by Zeus as a

swan. Queen Leda gave

birth to two immortal

children, one of them

being Helen of Troy, and

was herself immortalized

in the heavens as Cygnus

the swan constellation.

Cygnus is the 16th

largest constellation, and

located in the fourth

quadrant of the northern hemisphere (NQ4). It is visible at latitudes between 90° and -40°. The constellations that

border Cygnus are Cepheus, Draco, Lacerta, Lyra, Pegasus, and Vulpecula. The best way to locate Cygnus in the

night sky is by finding the North Star and looking toward Aquarius, as Cygnus is between them.

The constellation Cygnus contains 10 stars with known planets and two Messier objects. The most notable

stars in Cygnus are the five that form the Northern Cross: Daneb (Alpha Cygni), Delta Cygni, Albireo (Beta

Cygni), Gienah (Epsilon Cygni), and Sadr at the center (Gamma Cygni). There are many interesting deep sky

objects in Cygnus. The interesting deep sky objects are the Fireworks Galaxy, the Cocoon Nebula, the Veil

Nebula, and the North American Nebula.

Star chart of Cygnus constellation.

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October Cepheus

The constellation Cepheus was created by Ptolemy in the 2nd century as a mate to the Cassiopeia

constellation. Cepheus was a King of Ethiopia in Greek mythology. He was the husband of Queen Cassiopeia,

and father of Andromeda. King Cepheus was the one who consulted the oracles who told him to sacrifice his

daughter Andromeda to the sea monster in order to appease Poseidon, and she was then rescued by Perseus.

Cepheus is located in the fourth quadrant of the Northern Hemisphere (NQ4), and can be seen at

latitudes between 90° and -10°. The constellations that border Cepheus are Camelopardalis, Cassiopeia,

Cygnus, Draco, Lacerta, and Ursa Minor. The best way to find Cepheus in the night sky is to find the North Star

and look around it for Cepheus’ brightest star Alderamin.

The constellation Cepheus contains only one star with known planets and no Messier objects. The

brightest star is Alderamin (Alpha Cephei) at 2.51 apparent visual magnitude, and can be seen with the naked

eye. The most interesting deep sky objects in Cepheus are the Iris Nebula and the Wizard Nebula.

Star map of Cepheus.

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November Cassiopeia

The constellation Cassiopeia was

created by the Greek astronomer Ptolemy in

the 2nd century. In Greek mythology,

Cassiopeia is the beautiful and vain wife of

King Cepheus of Ethiopia, who caused an

uproar when she boasted that she was more

beautiful than all of the nymph daughters of

the Titan Nereus. Enraged, the nymphs

begged Poseidon, who was married to one

of them, to punish Cassiopeia. Poseidon

decided to send the sea monster Cetus (the

whale constellation) to ravage the coast of

Cepheus’ kingdom. The king was distraught

and asked an oracle what to do, who in turn

told Cepheus to sacrifice his daughter

Andromeda to the sea monster. The hero

Perseus happened by and saved Andromeda, and later married her. At their wedding, however, an old suitor of

hers demanded that he had the rights to her, not Perseus, and attacked with a band of men. Perseus was

outnumbered, so he used the head of Medusa to turn all of his attackers to stone. Cassiopeia and Cepheus

accidentally looked at Medusa and were also killed, but Poseidon ultimately decided to send them to the

heavens as constellations. Cassiopeia was condemned to circle the celestial pole forever in order to spend half

of the year upside-down as punishment for her vanity. She is still sometimes depicted sitting on her throne,

arrogantly combing her hair.

Cassiopeia is located in the first quadrant of the Northern Hemisphere (NQ1), and can be seen from

latitudes between 90° and -20°. It is easiest to find in the night sky by locating Polaris the North Star, and

looking for the “W” shape to the southwest. Cassiopeia is bordered by the constellations Andromeda (her

daughter in mythology), Camelopardalis, Cepheus (her husband in mythology), Lacerta, and Perseus (her

mythological son-in-law).

The constellation Cassiopeia has three stars with known planets, with its brightest star being Schedar (Alpha

Cassiopeiae), at a 2.20 visual magnitude. The bright stars that form the “W” are from left to right: Epsilon,

Delta, Gamma, Alpha, and Beta Cassiopeiae. Some striking and notable deep sky objects in Cassiopeia are the

Supernova remnant in Cassiopeia A, the Heart Nebula, IC 1848, and the Bubble Nebula.

Star Chart of Cassiopeia.

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December Fornax

The constellation Fornax was created by the French astronomer Nicolas Louis de Lacaille in 1756. It

was originally named Fornax Chemica, the chemical furnace, but it was shortened to Fornax (Latin for “the

furnace”) in 1845 by John Herschel. There is no European myth associated with Fornax, however, in Chinese

astronomy, the stars of Fornax represent Xi Fang Bai Hu, the White Tiger of the West. The tiger, king of beasts,

is said to only turn white after 500 years of age, and only appears when the world is filled with peace and virtue.

The White Tiger is a mythological guardian of the west.

Fornax is located in the first quadrant of the Southern Hemisphere (SQ1), and can be seen from latitudes

between 50° and -90°. It is easiest to find in the night sky by looking to the right of the bright star Sirius and the

stars of Orion’s belt. Fornax is bordered by Cetus, Eridanus, Phoenix, and Sculptor.

The constellation Fornax has 4 stars with known planets, no Messier objects, and its brightest star is

Alpha Fornacis, whose visual magnitude is only 3.85. There are a few interesting deep sky objects in Fornax,

like NGC 1097 which is a barred spiral galaxy, along with the Fornax Galaxy Cluster, and the NGC 1049

globular cluster. My favorite deep sky object in Fornax is the black hole in the center of the NGC 1097 galaxy,

with a visible surrounding quasar.

Star Chart of Fornax.

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References Mensa: Credner, T.; Kohle, S. (2014). The deep photographic guide to the constellations: The constellation of the

month: January. Allthesky.com. Retrieved from:

http://www.allthesky.com/constellations/dorado/constell.html

No Name Given, (2014). Constellation guide: Mensa constellation. Constellation-guide.com.

Retrieved from: http://www.constellation-guide.com/constellation-list/mensa-

constellation/

Ridpath, I. (No date found). Mensa: The table mountain. Ianridpath.com. Retrieved from:

http://www.ianridpath.com/startales/mensa.htm

Monoceros: No Name Given, (2014). Constellation guide: Monoceros constellation. Constellation-

guide.com. Retrieved from: http://www.constellation-guide.com/constellation-

list/monoceros-constellation/

Carina: No Name Given, (2014). Constellation guide: Carina constellation. Constellation-guide.com.

Retrieved from: http://www.constellation-guide.com/constellation-list/carina-constellation/

Ursa Major: No Name Given, (2014). Constellation guide: Ursa major constellation. Constellation-

guide.com. Retrieved from: http://www.constellation-guide.com/constellation-list/ursa-

major-constellation/

Centaurus: Anne’s Astronomy News (2013). The Running Chicken Nebula, an emission nebula in Centaurus.

AnnesAstronomyNews.com. Retrieved from: http://annesastronomynews.com/photo-gallery-ii/nebulae-

clouds/ic-2944-the-running-chicken-nebula-or-the-lambda-cen-nebula-is-an-open-cluster-with-an-

associated-emission-nebula-6500-light-years-away-in-centaurus-it-features-bok-globules-and-most-

likely-active-2/

No Name Given, (2014). Constellation guide: Centaurus constellation. Constellation-guide.com.

Retrieved from: http://www.constellation-guide.com/constellation-list/centaurus-constellation/

www.wikisky.org

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Libra: No Name Given, (2014). Constellation guide: Libra constellation. Constellation-guide.com.

Retrieved from: http://www.constellation-guide.com/constellation-list/libra-constellation/

Scorpius: Dunbar, B. (2013). The butterfly nebula. Nasa.gov. Retrieved from: http://www.nasa.gov/

multimedia/imagegallery/image_feature_2526.html#.VCpFDvldVLk

No Name Given, (2014). Constellation guide: Scorpius constellation. Constellation-guide.com.

Retrieved from: http://www.constellation-guide.com/constellation-list/scorpius-constellation/

Sagittarius: No Name Given, (2014). Constellation guide: Sagittarius constellation. Constellation-

guide.com. Retrieved from: http://www.constellation-guide.com/constellation-

list/sagittarius-constellation/

Cygnus: No Name Given, (2014). Constellation guide: Cygnus constellation. Constellation-guide.com.

Retrieved from: http://www.constellation-guide.com/constellation-list/cygnus-

constellation/

Cepheus: No Name Given, (2014). Constellation guide: Cepheus constellation. Constellation-guide.com.

Retrieved from: http://www.constellation-guide.com/constellation-list/cepheus-

constellation/

Cassiopeia: No Name Given, (2014). Constellation guide: Cassiopeia constellation. Constellation-

guide.com. Retrieved from: http://www.constellation-guide.com/constellation-

list/cassiopeia-constellation/

Fornax: No Name Given, (2014). Constellation guide: Fornax constellation. Constellation-guide.com.

Retrieved from: http://www.constellation-guide.com/constellation-list/fornax-constellation/