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Don't Worry: This Catch is Dolphin-Safe
Observing >
Let's go hunting for dolphins. Not the kind of hunting that will get us into international trouble. We'll pursue our prey above, in the oceans of the summer sky, for Delphinus, one of the so-called "minor" constellations.
This will also give us an interesting look into how other cultures have named the skies. But first we have t find our Flipper-like friend.
Go outside in the next few evenings and face east. Look up almost directly above your head. There on the great ceiling above is the Summer Triangle. There are two stars that make up the base of the triangle. The one to the right is Altair; to the left is Deneb.
Follow an imaginary line from Altair a third of the way back toward Deneb. Stop! Now look the same distance downwards. You'll see a collection of stars that looks like a kite. Use your imagination and you may even see ... a dolphin! That's diminutive Delphinus, our star constellation this month.
There are several fish stories related to this minor constellation. One myth is the tale of how a messenger dolphin convinced the sea nymph Amphitrites to marry Poseidon. Its reward for being a successful matchmaker? A place of honor in the sky.
Another
myth related to Delphinus has a dolphin saving the life of the ancient
Greek poet Arion after he was chucked into the ocean by a scurvy gang
of mutineers. The Arab culture embraced that dapper Greek dolphin and
called it Dulfim, a sort of savior to submerging sailors.
Biblical peoples saw Delphinus as the Leviathan of the beautiful Creation Psalm, Psalm 104. And the Hindu people perceived there a portly porpoise, Zizumara.
It's hard to find a non-nautical theme anywhere.
The stars themselves that make up Delphinus are not the most interesting critters in the sky. They are typical stars, 100-300 light years away. What's more interesting, though, are their names.
For example the tail of the kite (or dolphin) --- the brighter star to the right --- is known to astronomers as Epsilon Delphini. The Chinese called this little stray Pae Chaou, which means --- ahem --- The Rotten Melon. Personally, I think that name stinks.
To some early Christian sects the entire constellation of Delphinus was known as the Cross of Jesus, and Epsilon Delphini itself was known in Arabia by a related name, Al Amud al Salib, The Pillar of the Cross.
But the most mysterious names belong to the two brightest stars in the constellation, Alpha and Beta Delphini. They would be the most northwesterly ones. Alpha is known commonly as Sualocin, Beta is called Rotanev. Both were first christened thusly in the Palermo Star Catalogue of 1814. But where did those names come from?
The Reverend Thomas W. Webb, an English astronomer in the 19th century, discovered the answer to the mystery:
In the early 1800's, the Palermo Observatory was headed by astronomer Giuseppe Piazzi. He's best known for discovering and naming the first asteroid, Ceres. He had an assistant named Niccolo Cacciatore. Cacciatore's Latin name was Nicolaus Venator.
Apparently
Piazzi, in naming the two stars, reversed the spelling of Nicolaus to
Sualocin, and Venator to Rotanev, in this way honoring his assistant and
dauphin (successor).
Here's an interesting activity I use in class and you can use if you teach. Give the students a blank star chart. Let them draw in their own constellations and create their own stories to go with them. You'd be amazed at the stories they can come up with.
Questions or comments? Mark Ritter can be reached here.
Posted by Administrator at 2002.08.17 02:36 PM | Comments (0)
