Delightful Delphinus is a must-see in the sky

Contributed

I’ve been meaning to tell you about the tiny constellation Delphinus the Dolphin and I’m happy to get to it finally.

Less than a hundred years ago, the International Astronomical Union officially divided the sky into eighty-eight constellations to standardize the night sky worldwide. Forty-eight of those constellations were cataloged by the Greek astronomer Ptolemy in the Second Century. Since then, the other 40 have been gradually added, many of them in the southern hemisphere.

Delphinus the Dolphin is one of Ptolemy’s original constellations. Even though it’s small and dim, it’s very distinct. It’s one of the few constellations that really looks like what it’s supposed to be. Even though it’s the 19th smallest constellation, it’s one of my very favorites. Once you see it, you’ll never forget it. Delphinus is made up of a petite, skinny diamond of faint stars that outlines the torso and head of the little dolphin and a single faint star that marks the tail. Delphinus is swimming in the celestial sea in the western sky these early evenings after twilight.

Even though the five main stars that make up dainty Delphinus look faint to us, nothing could be further from the truth. Each one of those stars is much larger and way more powerful than our sun, and they kick out much more light and energy than our home star. Their faintness in our night sky is simply due to their vast distance from us. They range from 95 light-years to over 360 light-years away.

Throughout the ages, people have used constellations to tell stories tied to local religion or mythology. That’s 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 the Greek mythology tales about Delphinus. It involves Poseidon, the god of the sea. As with most Greek gods, Poseidon was quite a playboy who got around in his youth. After many years he tried to domesticate himself 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, and it was their mission to provide safety and protection for sailors and fishermen.

Despite Poseidon’s attempted charm and all his wooing, Amphitrite was underwhelmed and avoided him like the plague. She hated the god of the sea. Poseidon wasn’t about to quit his ill-fated pursuit. He was determined to have his prize, so he kidnapped Amphitrite and put her in a cage. How about that for charm and class?

One day, when one of Poseidon’s guards opened the cage door, she screamed at him at the top of her lungs. It was such a high pitch that it stunned the guard just long enough for her to slip out behind him, swimming her tail off as fast and far as she could.

Even after Amphitrite’s great escape Poseidon didn’t give up. He vowed to change his ways and actually become a nice guy. He sent Delphinus, his faithful and magical dolphin, to search for Amphitrite. Not only could Delphinus talk but he was a diplomat as well. He managed to find Amphitrite and persuaded her to give Poseidon another chance. She finally agreed, climbed on Delphinus’s back and rode back to the god of the 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.

It might take a little work to find the little Dolphin in the sky, but it’s so worth it.

Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul and is author of the book, “Stars, a Month by Month Tour of the Constellations” published by Adventure Publications. Send questions to mikewlynch@comcast.net .

The Rochester Astronomy Club welcomes new members and puts on public star parties. Their website is rochesterskies.org .