The Sea or the Water is an area of the sky in which many water-related, and few land-related, constellation

Constellation

In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....

s occur. This may be because the Sun passed through this part of the sky during the rainy season.

Most of these constellations are named by Ptolemy

Ptolemy

Claudius Ptolemy , was a Roman citizen of Egypt who wrote in Greek. He was a mathematician, astronomer, geographer, astrologer, and poet of a single epigram in the Greek Anthology. He lived in Egypt under Roman rule, and is believed to have been born in the town of Ptolemais Hermiou in the...

:

• Aquarius
  Aquarius (constellation)
  Aquarius is a constellation of the zodiac, situated between Capricornus and Pisces. Its name is Latin for "water-bearer" or "cup-bearer", and its symbol is , a representation of water....
  
   the Water-bearer
• Capricornus
  Capricornus
  Capricornus is one of the constellations of the zodiac; it is often called Capricorn, especially when referring to the corresponding astrological sign. Its name is Latin for "horned male goat" or "goat horn", and it is commonly represented in the form of a sea-goat: a mythical creature that is half...
  
   the Sea-goat
• Cetus
  Cetus
  Cetus is a constellation. Its name refers to Cetus, a sea monster in Greek mythology, although it is often called 'the whale' today. Cetus is located in the region of the sky that contains other water-related constellations such as Aquarius, Pisces, and Eridanus.-Ecliptic:Although Cetus is not...
  
   the Whale
• Delphinus
  Delphinus
  Delphinus is a constellation in the northern sky, close to the celestial equator. Its name is Latin for dolphin. Delphinus was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains among the 88 modern constellations recognized by the International Astronomical...
  
   the Dolphin
• Eridanus
  Eridanus (constellation)
  Eridanus is a constellation. It is represented as a river; its name is the Ancient Greek name for the Po River. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations. It is the sixth largest of the modern...
  
   the Great River
• Hydra
  Hydra (constellation)
  Hydra is the largest of the 88 modern constellations, measuring 1303 square degrees. It has a long history, having been included among the 48 constellations listed by the 2nd century astronomer Ptolemy. It is commonly represented as a water snake...
  
   the Water serpent
• Pisces
  Pisces (constellation)
  Pisces is a constellation of the zodiac. Its name is the Latin plural for fish, and its symbol is . It lies between Aquarius to the west and Aries to the east...
  
   the Fishes
• Piscis Austrinus
  Piscis Austrinus
  Piscis Austrinus is a constellation in the southern celestial hemisphere. The name is Latin for "the southern fish" in contrast with the larger constellation Pisces, which represents a pair of fishes. Prior to the 20th century, it was also known as Piscis Notius...
  
  , the Southern Fish (not named by Ptolemy)

Sometimes included are the Argo Ship

Argo Navis

Argo Navis was a large constellation in the southern sky that has since been divided into three constellations. It represented the Argo, the ship used by Jason and the Argonauts in Greek mythology...

 and Crater

Crater (constellation)

Crater is a constellation. Its name is Latin for cup, and in Greek mythology it is identified with the cup of the god Apollo. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations...

 the Water Cup.

Some water-themed constellations are newer, so are not in this region. They include Hydrus

Hydrus

Hydrus is a small constellation in the southern sky, created in the sixteenth century. Its name means "male water snake", and it should not be confused with Hydra, a much larger constellation which represents a female water snake.-History:...

, the lesser water snake; Volans

Volans

Volans is a constellation in the southern sky. It represents a flying fish; its name is a shortened form of its original name, Piscis Volans...

, the flying fish; and Dorado, the swordfish.