#multiple star system

Delphinus, which is Latin for "dolphin," is the first of the constellations in the "Heavenly Waters" family. This is an area of sky between Sagittarius and Orion filled with dim constellations all associated with water thanks to the Mesopotamians.

Delphinus is one of the smaller constellations, but it is one of the original 48 constellations written about by Greek astronomer Ptolemy in the 2nd century. According to Greek mythology, this dolphin was sent out by Poseidon to find the nereid Amphitrite whom Poseidon wanted to marry. Delphinus did find Amphitrite and convinced her to accept Poseidon's hand in marriage.

There are several named stars here. In order of brightness:

Rotanev (β Delphini) is a binary star system consisting of two equally-bright yellow-white giant stars. The system lies about 101 light years away. Its name has an origin in a practical joke! The Italian astronomer Niccolò Cacciatore worked at and eventually led the Palermo Observatory. His boss, Giuseppe Piazzi published a star atlas, and attached to this star was the obscure name "Rotanev." Niccolò had added this name in honor of himself! His name in English was Nicholas Hunter, which is Latinized to Nicolaus Venator. "Venator" backwards is "Rotanev"!

Sualocin (α Delphini) is an octuple star system with a central triple system consisting of at least one blue-white giant. The entire system lies about 254 light years away. Its name shares its origin with Rotanev: "Sualocin" is "Nicolaus" backwards!

Aldulfin (ε Delphini) is a solitary blue giant star about 330 light years away. Its name comes from the Arabic phrase ðanab ad-dulfīn meaning "the dolphin's tail."

Musica (18 Delphini) is a binary star system consisting of a yellow giant and a red dwarf. The system lies about 245 light years away. It has one confirmed exoplanet orbiting it, about 9 times the mass of Jupiter, named Arion. Both names were given by the people of Japan: Musica is Latin for "music," while Arion is a Greek poet and musician who was supposedly saved at sea by dolphins.

Crux, which is Latin for "cross," is the smallest of the 88 constellations, but probably one of the most recognizable. That probably explains why it appears on the flags of Australia, Brazil, New Zealand, Papua New Guinea, and Samoa!

Although it was probably known to the Ancient Greeks since Ptolemy included these stars are part of Centaurus, Earth's precession slowly moved Crux below the horizon for most of Europe. The first more modern person to notice the Cross was the Portuguese astronomer João Faras in 1500 while he was accompanying an expedition to Brazil. However, it was Dutch cartographer Petrus Plancius who made it its own constellation in 1598, nearly a century later!

The named stars, in order of brightness, are:

Mimosa (β Crucis), a binary star system consisting of two blue giant stars separated by only about 9 AU (about the distance between the Sun and Saturn). The system lies about 280 light years away. Its name does not come from the drink, but comes from the Latin word mimosa meaning "actor."

Acrux (α Crucis) is a septuple star system consisting of several blue giants and at least one red dwarf. The entire system lies about 348 light years away. The name is an Americanism of Alpha Crucis.

Gacrux (γ Crucis) is a red giant star about 89 light years away, making this the nearest red giant to Earth. Its name is again an Americanism of Gamma Crucis.

Imai (δ Crucis) is a blue giant star about 345 light years away. Its name was given by the Mursi people of Ethiopia: when Imai stops appearing in the evening sky right at dusk, it is said that the Omo river rises high enough to flatten the imai grass along its banks.

Ginan (ε Crucis) is a solitary orange giant star about 230 light years away. Its name was given by the Wardaman people of Australia: this refers to a dillybag, a woven bag used to gather and carry food.

Lumbung (39 Crucis) is a solitary blue giant star about 840 light years away. Its name was given this year, coming from Bali. Lumbung was the name of this constellation in Indonesian astronomy, referring to a rice barn or granary.

Puppis, which is Latin for "poop deck" or "stern," is the largest part of the ship, Argo Navis. The entire constellation was known to the ancient Greeks, but it was a very large and overwhelming constellation. In 1752, the French astronomer Nicolas Louis de Lacaille split the ship into its constituent parts.

There are several named stars in Puppis. In order of brightness:

Naos (ζ Puppis), a solitary blue supergiant star about 1,080 light years away. It is one of the hottest and most luminous stars in the night sky visible to the unaided eye. Its name comes from the Greek word ναύς meaning "ship."

Tureis (ρ Puppis) is a solitary yellow-white supergiant star about 63 light years away. It is also a variable star, changing brightness about 7 times a day. Its name comes from the Arabic word turays meaning "shield."

Pipit (ν Puppis) is a solitary blue giant star about 370 light years away. Its name comes from the Kendayan people of Indonesia, sharing its name with a local bird.

Azmidi (ξ Puppis) is a binary star system consisting of at least one yellow supergiant star. The entire star system lies about 1,200 light years away. Its name comes from the Greek word Aspidiske meaning "little shield."

Nosaxa (HD 48265) is a Sun-like star about 296 light years away. It has two confirmed exoplanets orbiting it, the smaller of which (about 1.5 times the mass of Jupiter) is named Naqaȳa. Both names were given by the people of Argentina: Nosaxa means "springtime" and Naqaȳa means "brother" in the local Mocoví language.

Moth (HD 61005) is a Sun-like star about 119 light years away. It doesn't have a confirmed exoplanet, but it does have a debris disk. The shape of this debris disk resembles the wings of a moth, which inspired its name.

Dilmun (WASP-121) is a Sun-like star about 858 light years away. It has one confirmed exoplanet orbiting it, about the mass of Jupiter, named Tylos. Both names were given by the people of Bahrain: Dilmun is the name of an ancient civilization that inhabited the area, while Tylos is the ancient Greek name for Bahrain.