Delphinus


Delphinus (Pronounced /dɛlˈfnəs/ or /ˈdɛlfɪnəs/) is a small constellation in the Northern Celestial Hemisphere, close to the celestial equator. Its name is the Latin version for the Greek word for dolphin (δελφίς). It is one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations recognized by the International Astronomical Union. It is one of the smaller constellations, ranked 69th in size. Delphinus' five brightest stars form a distinctive asterism symbolizing a dolphin with four stars representing the body and one the tail. It is bordered (clockwise from north) by Vulpecula, Sagitta, Aquila, Aquarius, Equuleus and Pegasus.

Delphinus is a faint constellation with only two stars brighter than an apparent magnitude of 4, Beta Delphini (Rotanev) at magnitude 3.6 and Alpha Delphini (Sualocin) at magnitude 3.8.

According to myth, the first Greek god Poseidon wanted to marry Amphitrite, a beautiful nereid. However, wanting to protect her virginity, she fled to the Atlas mountains. Her suitor then sent out several searchers, among them a certain Delphinus. Delphinus accidentally stumbled upon her and was able to persuade Amphitrite to accept Poseidon's wooing. Out of gratitude the god placed the image of a dolphin among the stars.[2]

The second story tells of the Greek poet Arion of Lesbos (7th century BC), who was saved by a dolphin.[3] He was a court musician at the palace of Periander, ruler of Corinth. Arion had amassed a fortune during his travels to Sicily and Italy. On his way home from Tarentum his wealth caused the crew of his ship to conspire against him. Threatened with death, Arion asked to be granted a last wish which the crew granted: he wanted to sing a dirge.[4] This he did, and while doing so, flung himself into the sea. There, he was rescued by a dolphin which had been charmed by Arion's music. The dolphin carried Arion to the coast of Greece and left.[5]

In Chinese astronomy, the stars of Delphinus are located within the Black Tortoise of the North (北方玄武, Běi Fāng Xuán Wǔ).[6]

In Polynesia, two cultures recognized Delphinus as a constellation. In Pukapuka, it was called Te Toloa and in the Tuamotus, it was called Te Uru-o-tiki.[7]


Delphinus is depicted on the left of this card from Urania's Mirror (1825)
The constellation Delphinus as it can be seen by the naked eye
Contrast and color enhanced photograph of Delphinus
Animation fading-in of Aquila, Delphinus, Sagitta, and the summer Milky Way as seen in Dark-sky preserve Westhavelland