Earth and Sky Every Child Should Know Part 16

For myself, I do not believe any of these stories. One reason why I don't is that a seventh star is really there, and many people can really see it. Indeed, there are some people so sharp-eyed that on clear nights they can see anywhere from eight to eleven. And, what is more, they can draw a map or chart showing just where each star seems to them to be.

But the most wonderful stories about the Pleiades are the true stories.

One is that there are really more than 3,000 stars among the Pleiades.

Some of them can be seen only with the biggest telescopes. Others are revealed only by the spectroscope. And some can be found only by means of photography.

But the most amazing thing about the Pleiades is the distances between them. They look so close together that you would probably say "the moon seems bigger than all of them put together." Sometimes the moon comes near the Pleiades, and you expect that the moon will blot them all out.

But the astronomers say the full moon sails through the Pleiades and covers only one of them at a time, as a rule. They even say it is possible for the moon to pa.s.s through the Pleiades without touching one of them! I should like to see that. If anything like it is going to occur, the magazine I spoke of in the first chapter will tell me about it. And you'd better believe I will stay up to see that, if it takes all night!

There are two more constellations in the southern part of the sky that ought to be interesting, because they are the two hunting dogs that help Orion fight the Bull. But I can't trace these animals, and I don't believe it is worth while. The brightest stars in them everybody can see and admire--Sirius, the Bigger Dog, and Procyon, the Smaller Dog.

Every one ought to know Sirius, because he is the brightest star of all.

(Of course, he is not so bright as Venus and Jupiter, but they are planets.) To find him, draw a line from the eye of the Bull through the belt of Orion and extend it toward the southeast about twenty degrees.

They call him the Dog star because he follows the heels of Orion. And people still call the hottest days of summer "dog days" because 400 years before Christ the Romans noticed that the Dog star rose just before the sun at that time. The Romans thought he chased the sun across the sky all day and therefore was responsible for the great heat. But that was a foolish explanation. And so is the old notion that dogs are likely to go mad during the dog days "because the dog star is in the ascendant." So is the idea that Sirius is an unlucky star.

There are no lucky or unlucky stars. These are all superst.i.tions, and we ought to be ashamed to believe any superst.i.tion. Yet for thousands of years before we had public schools and learned to know better, people believed that every one was born under a lucky star or an unlucky one, and they believe that farmers ought to plant or not plant, according to the size of the moon. Now we know that is all bosh. Those old superst.i.tions have done more harm than good. One of the most harmful was the belief in witches. Let us resolve never to be afraid of these old tales, but laugh at them.

Why should anybody be afraid of anything so lovely as Sirius? I used to think Sirius twinkled more than any other star. But that was bad reasoning on my part. I might have noticed that every star twinkles more near the horizon than toward the zenith. I might have noticed that stars twinkle more on clear, frosty nights than when there is a little uniform haze. And putting those two facts together I might have reasoned that the stars never really twinkle at all; they only seem to. I might have concluded that the twinkling is all due to the atmosphere--that blanket of air which wraps the earth around. The nearer the earth, the thicker the air, and the more it interferes with the light that comes to us from the stars.

They say that Sirius never looks exactly alike on two successive nights.

"It has a hundred moods," says Mr. Serviss, "according to the state of the atmosphere. By turns it flames, it sparkles, it glows, it blazes, it flares, it flashes, it contracts to a point, and sometimes when the air is still, it burns with a steady white light." (Quotation somewhat altered and condensed.)

It is a pity that so fine a star as Procyon should be called the "Smaller Dog," because it suffers unjustly by comparison with Sirius. If it were in some other part of the sky we might appreciate it more, because it is brighter than most of the fifteen first-magnitude stars we can see. My brother William has grown to love it, but perhaps that is because he always "sympathizes with the under dog." He was the youngest brother and knows. And curiously enough he was nicknamed "the dog"--just why, I don't know.

To find Procyon, drawn a line from Sirius northeast about twenty degrees. And to make sure, draw one east from Betelgeuse about the same distance. These three stars make a triangle of which the sides are almost equal.

The name Procyon means "before the dog" referring to the fact that you can see him fifteen or twenty minutes earlier every night than you can see Sirius.

The only kind word about Procyon I have heard in recent years was in connection with that miserable business of Dr. Cook and the North Pole.

A Captain Somebody-or-other was making observations for Dr. Cook, and he wanted to know what time it was. He had no watch and didn't want to disturb any one. So he looked out of the window and saw by the star Procyon that it was eleven o'clock.

That sounds mysterious, but it is easy if you have a planisphere like ours. Last winter when we were all enjoying Orion, the Bull, and the two Dogs, I used to whirl the planisphere around to see where they would be at six o'clock at night, at eight, at ten, at midnight, and even at six o'clock in the morning. And so, if I waked up in the night I could tell what time it was without even turning my head. Sometimes I looked out of my window, saw Orion nearly overhead and knew it must be midnight. And sometimes I woke up just before daybreak and saw the great Bull backing down out of sight in the west, the mighty Hunter still brandis.h.i.+ng his club, and his faithful Dogs following at his heels.

SEVEN FAMOUS CONSTELLATIONS

There are only seven more constellations that seem to me interesting enough for every one to know and love all his life. These are:

The Lion (Spring)

The Twins (Spring)

The Virgin (Summer)

The Herdsman (Summer)

The Northern Crown (Summer)

The Scorpion (Summer)

Southern Fish (Autumn)

I have named the seasons when, according to some people, these constellations are most enjoyable. But these are not the only times when you can see them. (If you had that seventy-five-cent planisphere, now, you could always tell which constellations are visible and just where to find them.) No matter what time of year you read this chapter, it is worth while to go out and look for these marvels. You can't possibly miss them all.

Have you ever seen a Sickle in the sky? It's a beauty, and whenever I have seen it it has been turned very conveniently for me, because I am left-handed. It is so easy to find that I am almost ashamed to tell. But if you need help, draw a line through the Pointers backward, away from the Pole star, about forty degrees, and it will come a little west of the Sickle. The Sickle is only part of the Lion--the head and the forequarters. Only fanciful map-makers can trace the rest of the Lion.

The bright star at the end of the handle is Regulus, which means "king,"

from the stupid old notion that this star ruled the lives of men. To this day people speak of the "Royal Star," meaning Regulus. And at the end of this chapter I will tell you about three other stars which the Persians called "royal stars."

Another constellation which children particularly love is the Twins--Castor and Pollux. But the sailors got there first! For thousands of years the twins have been supposed to bring good luck to sailors. I don't believe a word of it. But I do know that sailors gloat over Castor and Pollux, and like them better than any other stars. The whole constellation includes all the stars east of the Bull and between the Charioteer and Procyon. But another way to outline the twins is to look northeast of Orion where you will see two rows of stars that run nearly parallel. To me the brothers seem to be standing, but all the old picture-makers show them sitting with their arms around each other, the two brightest stars being their eyes. The eyes are about five degrees apart--the same as the Pointers.

Pollux is now brighter than Castor, but for thousands of years it was just the other way. It is only within three hundred years that this change has taken place. Whether Castor has faded or Pollux brightened, or both, I do not know. Anyhow, Castor is not quite bright enough to be a first magnitude star. Three hundred years is a short time in the history of man, and only a speck in the history of the stars. Three hundred years ago they killed people in Europe just because of the church they went to. That was why the Pilgrim Fathers sailed from England in 1620, and made the first permanent settlement in America, except, of course, Jamestown, Va., in 1607.

There are plenty of stories about old Castor and Pollux, and, like all the other myths, they conflict, more or less. But all agree that these two brothers went with Jason in the s.h.i.+p Argo, shared his adventures and helped him get the golden fleece. And all agree that Castor and Pollux were "born fighters." And that is why the Roman soldiers looked up to these stars and prayed to them to help them win their battles.

Now for the four summer constellations every one ought to know. The first thing to look for is two famous red or reddish stars--Arcturus and Antares.

The way you find Arcturus is amusing. Look for the Big Dipper and find the star at the bottom of the dipper nearest the handle. Got it? Now draw a curve that will connect it with all the stars in the handle, and when you come to the end of the handle keep on till you come to the first very bright star--about twenty-five degrees. That is the monstrous star Arcturus, probably the biggest and swiftest star we can ever see with the naked eye in the northern hemisphere. He is several times as big as our sun, and his diameter is supposed to be several million miles. He is called a "runaway sun," because he is rus.h.i.+ng through s.p.a.ce at the rate of between two hundred and three hundred miles a second.

That means between seventeen and thirty-four million miles a day!

He is coming toward us, too! At such a rate you might think that Arcturus would have smashed the earth to pieces long ago. But he is still very far away, and there is no danger. Some people say that if Job were to come to life, the sky would seem just the same to him as it did 3,400 years ago. The only difference he might notice would be in Arcturus. That would seem to him out of place by a distance about three times the apparent diameter of the moon.

Some people believe this because Job said, "Canst thou guide Arcturus with his sons?" and therefore they imagine that he meant this red star.

But I believe he meant the Big Dipper. For in King James's time, when the Bible was translated into English, the word "Arcturus" meant the Big Dipper or rather the Great Bear. And for centuries before it meant the Great Bear. One proof of it is that "Arcturus" comes from an old Greek word meaning "bear"--the same word from which we get arctic. It is only within a few hundred years that astronomers have agreed to call the Great Bear "Ursa Major," and this red star Arcturus. So I think all the books which say Job mentioned this red star are mistaken. I believe Webster's Dictionary is correct in this matter, and I believe the Revised Version translates Job's Hebrew phrase more correctly when it says, "Canst thou guide the Bear with her train?"

Anyhow, Arcturus is a splendid star--the brightest in the constellation called the "Herdsman" or Bootes. It is not worth while to trace the Herdsman, but here is an interesting question. Is Arcturus really red?

The books mostly say he is yellow. They say he looks red when he is low in the sky, and yellow when he is high. How does he look to you? More yellow than red?

Well, there's no doubt about Antares being red. To find him, draw a long line from Regulus through Arcturus to Antares, Arcturus being more than half way between the other two. But if Regulus and the Sickle are not visible, draw a line from Altair, at right angles to the Eagle, until you come to a bright star about sixty degrees away. You can't miss Antares, for he is the only red star in that part of the sky.

Antares belongs to a showy constellation called the Scorpion. I cannot trace all the outline of a spider-like creature, but his poisonous tail or "stinger" is made by a curved line of stars south and east of Antares. And you can make a pretty fan by joining Antares to several stars in a curve which are west of Antares and a little north. There is an old tale that this Scorpion is the one that stung Orion to death when he began to "show off" and boast that there was no animal in the world that could kill him.

Another very bright star in the southern part of the sky is Spica. To find it, start with the handle of the Dipper, and making the same backward curve which helped you to find Arcturus, keep on till you come to the white star Spica--say thirty degrees beyond Arcturus. This is the brightest star in the constellation called "the Virgin." It is not worth while trying to trace her among nearly forty faint stars in this neighbourhood. But she is supposed to be a winged G.o.ddess who holds up in her right hand an _ear of wheat_, and that is what Spica means.

Now for an autumn constellation--the Southern Fish. I don't care if you fail to outline a fish, but I do want you to see the bright star that is supposed to be in the fish's mouth. And I don't want you to balk at its hard name--Fomalhaut (p.r.o.nounced _fo'-mal-o_). It is worth a lot of trouble to know it as a friend. To find it, you have to draw an exceedingly long line two-thirds of the way across the whole sky. Start with the Pointers. Draw a line through them and the Pole star and keep clear on until you come to a solitary bright star rather low down in the south. That is Fomalhaut. It looks lonely and is lonely, even when you look at it through a telescope.

And now for the last story. Once upon a time the Persians thought there must be four stars that rule the lives of men. So they picked out one in the north and one in the south and one in the east and one in the west, just as if they were looking for four bright stars to mark the points of the compa.s.s. If you want to find them yourself without my help don't read the next sentence, but shut this book and go out and see. Then write down on a piece of paper the stars you have selected and compare them with the list I am about to give. Here are the four royal stars of the Persians: Fomalhaut for the north, Regulus for the south, Aldebaran for the east, and Antares for the west.

Why doesn't this list agree with yours? Because Persia is so far south of where we live. Ah, there are very few things that are absolutely true. Let's remember that and not be too sure: for everything depends upon the point of view! I hope you will see Fomalhaut before Christmas, before he disappears in the west. He is with us only five months and is always low--near the horizon. But the other seven months in the year he gladdens the children of South America and the rest of the southern hemisphere, for they see him sweeping high and lonely far up into their sky and down again.

But the loveliest of all the constellations described in this chapter is the Northern Crown. It is not a perfect crown--only about half a circle--but enough to suggest a complete ring. Look for it east of Arcturus. I can see seven or eight stars in the half-circle, one of which is brighter than all the others. That one is called "the Pearl."

The whole constellation is only fifteen degrees long, but "fine things come in small packages"; and children grow to love the Northern Crown almost as much as they love the Pleiades.

THE TWENTY BRIGHTEST STARS