Les Constellations (The Constellations)
This unit will introduce 11 constellations and 2 asterisms. All of them can be pretty easily seen in January, when the unit will be taught. Here are the constellations we will study: The Twins (les Gémeaux), Orion, the Big Dog (le Grand Chien), the Little Dog (le Petit Chien), the Charioteer (le Cocher), the Bull (le Taureau), Cassiopeia (Cassiopée), Cepheus (Céphée), Andromeda (Andromède), the Whale (la Baleine), and Great Bear (la Grande Ourse). We will also study the Big Dipper (la Grande Louche) and the Little Dipper (la Petite Louche), which are 2 asterisms that are visible all year long. Constellations to be studied were chosen by taking into consideration not only the best times of year to see them, but also the apparent brightness of some or all of the stars that make up the constellations (so that students have a chance of spotting them if they try), as well as the appeal of the "pictures" formed by the constellations, and the stories that relate one constellation to the other. 4
I highly recommend creating your own version of the illustrations Rey made for his books. Printable overhead transparency sheets will work well for this. You can design the framework for the constellations (the star-dots) on the computer, using different-sized stars to represent the different magnitudes (be sure to include a key); then you can print another file that has only the imaginary lines you would use to connect-the-dots that will make an image out of the stars. You can begin like Rey does in Find the Constellations, by showing the star-dots and naming the constellation; then you can place the connecting-lines sheet over the star-dots sheet and label different parts of the image, like the handle and bowl of the Big Dipper. By working back and forth and alternating with and without the overlay, you can ease students into being able to identify the images with out the connecting-lines. Like Rey (on pages 18-19 and 22-23), I recommend creating different little mini quizzes to assess comprehension. First, give a sheet of the star-dot images with the connecting-lines, later, one of the images without connecting-lines; for each sheet, instruct students to provide the appropriate constellation names. For a more advanced quiz, rotate the star-dot images on the sheet, so that students must determine correct orientation of the image to identify it correctly.
Below I give some particulars on the stories behind each constellation, as well as information about the stars. There are many ways to transmit this information, a few of which will be shown in the Lesson Plans section of this unit. For notable stars in each constellation I give a color, which can be incorporated into the artistic renderings of the constellations. The other stars should not appear as remarkable as these; they should be more neutral in appearance. However, since they will be smaller in size to represent the difference in magnitude, they can be somewhat colorful; their size will not allow the color to stand out well anyway. The quantity of stars of each magnitude is given for each constellation so that you may be sure to provide enough supplies for students to create artistic renderings of the constellations.
Les Gémeaux / The Twins
The Twins lie in the zodiac, the band of sky through which the Sun seems to move. It follows the line of the ecliptic, which is the path that the Earth travels as it revolves around the Sun. In astrology, when it is said that someone is a Gemini, it is meant that when that person was born, the Sun looked as if it was in front of the Gemini constellation, or the area of sky represented by the Gemini constellation. 5
Rey says that the Twins look like "two matchstick men holding hands," and I think that says it perfectly! The two brightest stars of the constellation are named after the twins, Castor and Pollux, of Greek mythology; according to the myth, Pollux was immortal, Castor was not. When Castor was killed in battle, Pollux begged Zeus to bring him back to life; Zeus agreed to let Pollux share his immortality with his brother, but only in shifts so that, while one was alive, the other was "dead," in the underworld. It is said that through their constellation in the sky, they are finally able to be in the same place at the same time, together. In ancient times, people used to confirm oaths by saying "By Gemini," to prove their loyalty to the oath being taken. That phrase evolved over time into "By jiminy," and then become personified in the Disney character, Pinocchio's friend Jiminy Cricket.
Castor seems to be a single star of magnitude 1.6; it is actually a multiple star, made up of 6 different stars with magnitudes ranging from 1.9 to 9.0. For our purposes, we will treat it as a star of magnitude 2 (1.6 rounded up). The Castor stars are located 50 light-years away. Pollux is the 16 th brightest star in the sky; it has a magnitude of 1.2, which we will round to 1. It is located 34 light-years away. It is yellowish-orange in color. The constellation is made up of 1 1 st-magnitude star (Pollux), 2 2 nd-magnitude stars (one of which is Castor), 4 3 rd-magnitude stars, and 11 5 th-magnitude stars. To find The Twins, first locate the Charioteer; the Twins are just east of him.
Le Cocher / The Charioteer
Some say the Charioteer is named after the mythical inventor of the chariot; others say it represents any generic chariot driver. It is shaped like an angular face under a pointed hat. A good way to associate this constellation's name with its image is that the sharp angles of the image created by connecting the star-dots make his face look tough, like the driver of a battle wagon, or chariot. His eye is the yellowish, 1 st-magnitude star Capella, which is located 42 light-years away. It is the 6 th-brightest star in the sky, and is 16 times as large as the Sun. The constellation is made up of 1 1 st-magnitude star (Capella), 2 2 nd-magnitude stars, 3 stars of 3 rd-magnitude, and 2 of 4 th-magnitude. To find Capella from the Big Dipper, start at the first star of its handle, and draw a straight line that follows past the bowl and continues down. You will see three faint stars that form the nose, and can then locate the rest of the stars that form the Charioteer's face.
Cassiopée, Céphée, Andromède, la Baleine / Cassiopeia, Cepheus, Andromeda, Whale
According to Greek myth Cassiopeia was the Queen of Ethiopia, Cepheus was King, and Andromeda was their daughter. The story of these three begins with a foolish boast by a very beautiful and very vain Cassiopeia. Some sources say she said that she was more beautiful than the sea nymphs, who were goddesses of the sea, some say that she said her daughter was more beautiful; either way, the goddesses did not appreciate being compared to mere mortals. Neptune, a powerful Sea God, sent a whale (some say a sea-monster) to destroy their domain; to stop the destruction, Cepheus was told to sacrifice their daughter, Andromeda. He agreed to do so, and chained her to a rock by the sea. Just as the whale was about to swallow her, the hero Perseus killed it, rescued Andromeda, and then married her; he is also represented by a constellation, but not one that we will study here. They are said to have flown off on Perseus' winged horse, Pegasus, who is also represented by a constellation not addressed here.
Cassiopeia is a bright constellation located close to the Little Dipper and its Pole Star. She is recognizable by the W shape she makes in the sky. The traditional way of illustrating constellation images often does not correspond very well to a decipherable image; the picture is symbolically drawn around the star points, with much liberty taken in the interpretation. As you can see from Rey's books, his illustration technique is more simplistic and easier to associate with a true image. Unfortunately, the Cassiopeia constellation is a bit troublesome in this regard. The traditional image shows a full figure of the queen, but the Rey version leaves us with something that you can try to pass off as a queen's throne, but that really looks like an angular image of her two breasts. I will show my students the traditional image, and will then show how, if you include another star, you can form the seat of her throne. I expect that some student will volunteer his own opinion, and though I will not deny that I can see it, I will make a point of not adopting it. The Cassiopeia constellation is comprised of 3 stars of 2 nd-magnitude, 2 of 3 rd - and 1 of 4 th-magnitude.
Cepheus is a much dimmer constellation than Cassiopeia (which should not necessarily be construed as a statement on the intelligences of man versus woman!) His constellation forms an image of a pointed hat atop a man's face, much like the Charioteer. Cepheus' face makes an inlet for his mouth; it is not as angular and "tough-looking" as the Charioteer's, since he is a King and commands, but does not participate in, war. The biggest difference between the Cepheus and Charioteer constellations is that Cepheus has a pigtail at the nape of his neck, like an aristocrat would. The Cepheus constellation is made up of 3 stars of 3 rd-magnitude, 8 of 4 th-magnitude, and 1 of 5 th. To find Cepheus from the Big Dipper, follow the line of the Pointers past the Pole Star; it will hit the top side of his hat, close to its point.
The Andromeda constellation shows the girl lying down, with the chain affixed to her wrist. At her bent knee is a small hazy spot known as the Andromeda Nebula. It is a galaxy, and the most distant object the human eye can see unaided. The constellation is comprised of 3 2 nd-magnitude stars, 1 3 rd-magnitude, 13 4 th-magnitude, and 2 5 th-magnitude stars. It is easiest to spot her by first looking for the three brightest stars in line at her foot, rear end, and head.
The Whale is very difficult to spot, as all its stars are dim except for the one at his mouth. If you follow Andromeda's head-star diagonally down towards the left, you can spot the whale's mouth. It will be a fun challenge to see who can spot this one! The mouth is a 2 nd-magnitude star, there is 1 star of 3 rd-magnitude, and 12 of 4 th-magnitude. The Whale is also known as Cetus or the Sea Monster.
If you draw a straight line westward from Capella in the Charioteer, a straight line southward from the Pole Star, and look in the northwest quadrant formed by the intersection of those lines, you should see the upright W of Cassiopeia. Just northwest of Cassiopeia is Cepheus, facing her sideways, the point of his cap across from the east-most top of her W. Just southwest of Cassiopeia is Andromeda, lying flat, the bright star of her rear end just south of the west-most top of her mother's W. Along the same line, but further south, is the star at the mouth of the Whale.
Orion
Orion is one of the most recognizable constellations in the sky. He is named after an ancient Greek hunter-warrior; there are many different myths about him, across cultures and continents. In his constellation image, he carries a shield in his left hand, and holds a club over his head with his right; he's also got a sword hanging at his hip. (Designations of left and right are given according to the constellation, so that Orion's left hand will be the hand we see on his right side if we are looking at him.)
Orion has more bright stars than any other constellation. Rigel and Betelgeuse are 1 st-magnitude stars – Rigel is bluish-white and the 7 th brightest star in our sky, and Betelgeuse, reddish, is the 10 th brightest. Rigel is 33 times the diameter of the Sun, which classifies it as a giant star (any star with a diameter between 10 and 100 times that of the Sun). Betelgeuse is a supergiant because, with a diameter 400 times greater than that of the Sun, it easily meets the supergiant requirement of having a diameter of over 100 times the Sun's. Although Betelgeuse is so much larger and closer than Rigel, it does not appear as bright because Rigel is hotter. Towards the bottom of his sword is a star that looks kind of fuzzy; it is actually a luminous gas-cloud called the Great Orion Nebula.
Rigel is located at Orion's left foot, Betelgeuse at his right shoulder. The constellation is most recognizable by the three closely-spaced bright stars of his belt. He is located just south of the Twins. The Orion constellation is comprised of 2 1 st-magnitude stars (Rigel and Betelgeuse), 5 stars of 2 nd-magnitude, 4 of 3 rd, 9 of 4 th, 6 of 5 th, and 1 nebula.
Le Grand Chien et Le Petit Chien / Big Dog and Little Dog
Big Dog and Little Dog are Orion's hunting dogs. Big Dog is located just southeast of Orion, and Little Dog is north of Big Dog. As the Earth rotates, it looks like these dogs follow Orion across the sky. The brightest star in our sky, a bluish 1 st-magnitude star named Sirius, is located in the Big Dog constellation. Sirius is actually a double star; it has a twin (named Sirius B) that is so faint it can only be seen with a large telescope, during ideal viewing conditions. It is fairly close to us, at a distance of 9 light-years. Almost as close as Sirius is Procyon, at a distance of 10 light years; it too is a double star. Procyon, the 8 th brightest star in our sky, is one of the two visible stars that make Little Dog; the constellation is nothing more than a small line, at best representing a pup's tail. Procyon is Greek for before the dog; it rises about 40 minutes before Sirius, which is known as the Dog Star. Big Dog is made up of 1 1 st-magnitude star (Sirius), 4 2 nd-magnitude stars, 2 3 rd-magnitude stars, 5 4 th-magnitude stars and 1 5 th-magnitude star. Little Dog is made up of 1 1 st-magnitude star (Procyon) and 1 3 rd-magnitude star.
Le Taureau / The Bull
Like the Twins, The Bull lies in the zodiac. It is best known for the Pleiades, a small cluster of tiny stars that looks like a little silver cloud. Six of its stars are visible to the naked eye, although there are about five hundred within the cluster. The Pleiades are nicknamed the Seven Sisters; it is possible that in the past a seventh star was visible without telescopes, and some myths tell of a lost sister to account for the missing seventh star. Also noteworthy in this large constellation is Aldebaran, the 13 th brightest star; it is a 1 st-magnitude star, orangish-red in color, and represents the bull's eye. The bull's hindquarters are dimmer than its large head; Greek myth says that it is because the bull is really Zeus in disguise, swimming, his legs under water. The Bull is composed of 1 1 st -magnitude star (Aldebaran), 1 2 nd-magnitude star, 2 of 3 rd-magnitude, 15 of 4 th-magnitude, 3 of 5 th, and a cluster of tiny stars collectively called the Pleiades.
La Grande Louche, la Petite Louche, et la Grande Ourse / The Big Dipper, the Little Dipper, and Great Bear
What about the Dippers? Because of their popularity, I expect some students to be asking about the Dippers, wondering why we aren't discussing the Big or Little Dipper. Leaving them for last is purposeful, as we will need to introduce the idea of an asterism as opposed to a constellation. This will be easier after taking the time to discuss so many constellations. I also want to get students to ask for them, to tap into that desire for more.
Contrary to popular belief, the Big Dipper is not a constellation; it is an asterism. An asterism is a pattern formed by a part of an established constellation that doesn't appear on the official list of 88 constellations. The Big Dipper is that large, ladle-shaped image in the sky; the tip of its handle forms the snout of the Great Bear, and the bowl of the ladle forms a kind of saddle across his back. The outer edge of the bowl, or the back end of the saddle, is formed by two stars, called the Pointers; if you follow their slight curve, they will point you toward the Pole Star (the only bright star in that area, so easy to spot.)
The Pole Star, also known as Polaris and the North Star, is located at the very top of the Little Dipper's handle. No matter where you are, if you are facing the Pole Star you are facing north; it changes position so little in the sky that we can say it does not change at all. For a better explanation of why this is so, see the next section of this unit, entitled The Pole Star and Changing Sky Views. In the Northeast, The North Star will lie about halfway between the horizon and the point directly overhead (called the zenith).
The Little Dipper is also an asterism. It is part of the Little Bear constellation, but because the other stars of that constellation are very faint, we will content ourselves with looking for only the Little Dipper, and not Little Bear. The two stars that form the outer edge of its bowl are called the Guardians of the Pole, because they seem to march around the pole, like guardians.
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