Even in the night sky good things come in small packages! Back in 1922 the International Astronomical Union officially divided the sky into 88 constellations to standardize the night sky worldwide. 48 of these constellations were cataloged by the Greek astronomer Ptolemy in the 2nd century. The other 40 were added by several astronomers since then, with many of those in the southern hemisphere and southern portions of the northern hemisphere. Some are big and some are small. Some are bright and some are dim.
Delphinus the Dolphin is one of Ptolomyís original constellations. Even though itís small and dim itís also distinct, and is one of the few constellations that actually resembles what itís supposed to look like. Even though itís the 19th smallest constellation itís one of my very favorites! I love pointing it out at stargazing classes and parties. Once you see it youíll never forget it. Delphinus is made up of a small and skinny little diamond of faint stars that outlines the torso and head of the little Dolphin, and a single faint star that marks the tail. Currently Delphinus is swimming high in the southern skies at the start of evening.
The best way to find Delphinus is by using the famous ďSummer TriangleĒ. Despite the fact that weíre into autumn the Summer Triangle is nearly overhead in the high southern sky in the early evening. Itís very easy to spot. Just look for the three brightest stars that you can see overhead in the early evening this time of year and thatís the Summer Triangle.
This trio of bright stars is made up of stars from three separate constellations, each being the brightest star in their respective constellation. If you face toward the south and then crane your neck to nearly the top of the sky the brightest star youíll see will be Vega, on the right side of the Summer Triangle and the brightest star in the constellation Lyra the Harp. On the left corner of the triangle is Deneb, the brightest star in the constellation Cygnus the Swan. On the lower right corner is Altair, the brightest luminary in the constellation Aquila the Eagle. Itís from Altair that you start your quick search for the diminutive dolphin. Just gaze about two fist-widths at armís length to the left and up a little bit from Altair to find that skinny diagonally orientated diamond that makes up the body of the cute little dolphin in our celestial sea. The celestial dolphinís tail is marked by a star thatís just a little ways down and to the right of the diamond.
Heavenly looks can be deceiving! Even though the five main stars that outline the body and tail of Delphinus the Dolphin are fairly faint, each one of them is much larger and produces much more light and energy than the sun, our closest star. Their faintness in our night sky is simply due to these stars being a heck of a long ways away. They range in distance from 95 light-years to over 360 light-years away. Just one light-year, the distance that a beam of light travels in one yearís time, is almost six trillion miles away!
Throughout the ages, people have used constellations to tell stories tied to local religion or mythology. Thatís certainly the case with Delphinus. Many early Hebrew towns saw Delphinus as a whale, reminding them of the Old Testament story of Jonah and the whale. Early Christian settlements saw the little diamond of stars as the Cross of Jesus.
I love many of the Greek mythology tales. One story regarding Delphinus involves Poseidon, the god of the sea. As with all of the Greek gods, Poseidon was quite a playboy who really got around. This is a family column so Iíll just leave it at that. Anyway, when he finally decided to settle down and get married he set his sights on Amphitrite, one of the many Nereids that occupied his domain. Nereids, or sea nymphs, were like mermaids according to legend, in that they provided safety and protection for sailors and fisherman. Male mariners also found them easy on the eyes and very entertaining!
Despite Poseidonís slimy charm and all his wooing, Amphitrite was underwhelmed and got as far away as she could from the god of the sea. Poseidon did not give up easily though. He was on a love and lust mission and he didnít care what it took to pull it off. So what did he do? He kidnapped Amphitrite. What a sweetheart of a guy!
It was a struggle but Amphitrite managed to escape and swam her tail off as far as she could. Even after that happened, Poseidon refused to go through life without his favorite sea nymph. He sent Delphinus, his faithful dolphin, to search for Amphitrite. Delphinus wasnít just any dolphin though, because he was a talking dolphin and a diplomat! He managed to find Amphitrite and persuaded her to give Poseidon a chance. So she climbed on Delphinusís back and rode back to the god of sea. They were happily married and as a reward, Poseidon placed his faithful dolphin in the heavens as the constellation we still see thousands of years later!
Again, Delphinus the Dolphin is navigating the celestial waters in the early evening southern sky. It might take a little work to find but itís worth it. I know it will become one of your favorite constellations!
Diagram of Delphinus the Dolphin ...Click