Star Dome in August

Star Dome In August

Star Dome: To some, our galaxy rises from the horizon on August nights like a boiling cloud of steam. We might see it as the smear left by a giant’s paintbrush, or – referring to our own name for it – a streaming puddle of spilled milk. Any such comparisons, however, pale beside the actuality of the Milky Way: our own spiral galaxy, composed of billions of stars and vast clouds of gas and dust.

Many bright stars dot the Milky Way as it stretches from Sagittarius to Cygnus ; most dominant are the three that comprise the summer triangle – Vega, Deneb and Altair. The constellation patterns themselves include some of the sky’s most distinctive groups: the Northern Cross in Cygnus, the teapot in Sagittarius, the row of three stars in Aquila, and the tiny figures of Sagitta the arrow and Delphinus the dolphin.

Another small constellation, set directly in the Milky Way, is Scutum the shield. Invented by Hevelius, its original name was Scutum Sobieskii; it was ‘placed” in the sky in honor of John Sobieski, king of Poland, who prevented the Turkish invasion of Vienna in 1683. Scutum is notable today not for any bright stars, but for the richness of the Milky Way within its borders.

August Sky. The Sky Dome rendering approximates the sky as it appears early in August. The same constellations are visible one hour earlier during the latter half of the mouth. To use this constellation finder, hold it overhead so the compass points up line with North, South, East and West in your backyard or viewing area. For example, to find constellations in the southern part of the sky hold the chart in front of you so the South compass point faces the southern horizon. Repeat this procedure for East, West and North. Since only the brighter stars are represented in this map, you should be able to trace out the geometrical shapes of the constellations with ease. To find planets, asteroids, etc., visible among the current month’s zodiacal constellations refer to the planet finder. Source of the photography : Stargazing.net

The Milky Way itself is the subject of innumerable legends and bits of folklore. Often depicted as a river, it has had many different names. In Arabia it was simply Al Nahr (the river); in ancient Mesopotamia it was river of the Divine Lady, wife of the heaven –god; in Japan, the Milky way was the Silver river. When the crescent moon was in the sky, the fish in the river were said to be frightened, believing the moon was a hook.

The most widespread conception of the Milky Way, however is that of the road. We find this idea in our own title, for the word “way” is an archaic synonym for “road” or “path”. The German Milch Strasse has the same meaning, as does the French Voie lactée.

Other nations, however, have or had different ideas about this road. In Sweden it is Winter street, and the Chinese know it as Yellow road. Among English peasantry it was called Watling Street, the name of an ancient highway stretching from Chester to Dover, while in Celtic countries, the Milky Way was Arianrod or Silver Street.

It follows naturally that if the Milky Way is a road, there should be legends concerning its travelers and their destinations. In summer, the Milky Way appears to rise from Earth toward the zenith; thus many stories tell how a road, rising from the edge of the world, leads to heaven. To the Norsemen, the Milky Way was the road that dead heroes followed to Valhalla, home of the gods (although in later times the rainbow assumed this function). American Indians had the same ideas, and the brighter stars along the Milky Way were the heroes’ campfires. Natives of Patagonia believed their dead friends were hunting ostriches along the way, and the early Hindus called it the path that Ahriman took to his throne in heaven.

In Northern India, the Milky Way is called the path of the snake, providing another example of widely separated peoples having similar sky legends; the Norse told of the Midgard serpent, a monstrous snake that surrounded the world. In some stories the serpent lived in the ocean, but elsewhere the Milky Way is either the home of the snake or the snake itself. The Akkadians also knew the galaxy as the great serpent.

A story from Finland tells of how the lovers Zulamith and Salai, wanting to be united in heaven, built a “starry bridge of light”; after they completed the task, they were joined together into the star Sirius. Another Finnish story returns us to the notion of the Milky Way as a river. To the Finns, Tuonela, the land of death, was surrounded by a wide river that has been identified by some as the Milky Way. On this river swam a black swan, singing a melodious mournful song. In order to win the hand of the daughter of Louhi, ruler of Pohjola, the hero Lemminkainnen was ordered to make his way to Tuonela and shoot the river-swan. The hero’s first arrow missed. Before he could aim another, a shepherd, determined to prevent the sacrilegious act, attacked Lemminkainen with his sword and killed the hero. After dismembering the body, the shepherd threw the pieces into the river, which carried them to the land of death.

Planet Finder. The chart shows the positions of the moon, planets and brightest asteroids for August. Letters within the cercles correspond to the letters beside each object in the data section above the map. Additional information about each object: R.A. = right ascension and Dec = declination, the two coordinates used to locate astronomical objects. Magnitude = a. The general coordianate system is indicated around the edge of the map

If the Milky Way is indeed the river surrounding Tuonela, it’s easy to see the swan (Cygnus) swimming down it, as well as Lemminkainen’s first arrow (Sagitta) narrowly missing the bird’s head.

The tale, incidentally, ends happily, for Lemminkainen’s mother wore a ring that turned chill when her son was in danger. Leaning in this manner of his death, she was able to restore her son to life and death by magic. The composer Jean Sibelius relates the story in his Four Stories for orchestra.

If Cygnus and Sagitta are the swam and the arrow, might Lemminkainen himself be in the sky? We could chose to see him in the constellation Hercules, in place of that hero. This would actually not be inappropriate, for Hercules has had more identifications in its long history that any other constellation. In fact, the name Hercules is a very recent title for this group, which originally had nothing to do with that greatest of Greek heroes. The Greeks themselves did not know the constellation by that name, and it was only during Roman times that Hercules finally found his way into the sky. The Greek called the group the kneeler – nameless man, bent on one knee with his other foot on the head of Draco the dragon.

The constellations may originally have been intended to represent the important occupations of the day: hunters, farmers or worriers. If so, Hercules’ identification has long been lost, because of the Greeks and early Arabs he was simply the anonymous kneeler. Aratos, in 270 B.C., wrote that “no one can clearly speak of him, no upon what task he is bent; but simply Kneeler they call him.” Also titled the leaper, the keen-eyed one, or the club wielder in Greek days , the man remained unnamed.

Why should this be so? We have seen that the Greeks were ingenious in devising stories to complement their sky figures. Yet there is a group that exists, so to speak, in a void. Today, of course, there are many constellations associated by legend with Hercules, but these are recent additions to skylore. Hercules’ upside-down orientation in the sky is yet another addition to the puzzle: no other constellation except Pegasus stands on its head in manner.

But if the Greek were reluctant to assign a name to a kneeler, other nations certainly were not. There is evidence that the group may have represented the Chaldeans’ great hero Gilgamesh. A Chaldean cylinder seal dating from about 3000 B.C. shows Gilgamesh resting on one knee, with the other foot propped on the head of the dragon Tiamat – the exact pose assigned the figure in the sky. The Greeks, in fact, may have adopted the figure of Gilgamesh into their own mythology, transforming him into Hercules in the process.

Later, Hercules was changed by the Arabians into the dancer, although the Arabian word is translated by some as posturer. Still other names for the constellations have been Prometheus, Theseus, Orpheus (fittingly enough, with Lyra the lyre nearby), and Ixion. The last is a name of a figure in Greek legend, who, after a crime committed against Zeus, was punished in Hades by being tide to a wheel that revolved forever. The constellation’s daily motion around the pole may even have suggested the story of Ixion to its inventors.

Surprisingly, there is no mention anywhere in old records of the famous globular cluster M-13. Its first appearance in any written record is in 1714, when it was first seen by Sir Edmond Halley. Since the cluster is visible to the naked eye on clear nights, it is remarkable that it successfully avoided recognition prior to Halley’s discovery.

Still one more mystery is associated with Hercules. The constellation is indistinct; the only easily recognizable pattern is the keystone, made up of third and fourth magnitude stars. Why, then, has the group been so important to so many nations? In old records, it is always one of the most prominent figures in the sky, despite its faintness and anonymity.

The checkered career of Hercules is something to puzzle over while observing it on a clear August night in the Star Dome.