Review from previous lessons:
The circumpolar constellations rotate in a tight circle around Polaris, the North Star. They are always above the horizon if you're in the northern hemisphere.
Other constellations are farther away from the North Star, and rise and set like the sun. Different constellations will be visible during prime star-watching time (from early darkness to bedtime) at different times of the year.
In the last lesson, we became familiar with Orion. Here he is with some of his closest neighbors. Can you spot him? Look for his belt, and then confirm by finding Rigel and Betelgeuse.
Orion, the Hunter:
The stars in Orion can be used to find other nearby constellations, much the same way that the pointer stars in the Big Dipper directed us so effectively toward Polaris.
We can use his belt, his shoulders, his dagger, and Rigel and Betelgeuse to find Canis Major, Canis Minor, Taurus, The Pleiades, Gemini, and Lepus.
That big white star you see is the only magnitude difference I'll show, but only because it is the single brightest star.
Follow Orion's belt down to the left. You'll come to a bright star, Sirius (it's a seriously bright star). It's so bright, in fact, that it's the brightest star you can see from Earth, other than our sun. That makes it the brightest star you can see from Earth at night.
Sirius is the diamond on the collar of the big dog. It is sometimes called the "dog star."
Ursa Major (the Big Dipper) is the Great Bear, and Ursa Minor (the Little Dipper) is the Little Bear. It probably follows, then, that if there is a BIG dog, there should probably be a LITTLE dog, too (the same logic follows for anything with Northern/Borealis or Southern/Australis in the title, as well).
Follow Orion's shoulders sideways to the left, and you'll come to Canis Minor, or the Little Dog.
The Little Dog is just two stars, so it looks more like a hot dog. The brighter of those two stars is called Procyon (PRO-see-ahn), which is Greek for "before the dog." This is in reference to how the stars rise. You will always see Procyon rise above the horizon before you see the "dog star," Sirius.
Canis Minor is one of the 88 modern constellations, but was not recognized by the ancient Greeks. According to the Greeks, Orion had only one dog.
Maybe she had puppies.
Taurus, the Bull:
Follow Orion's belt up to the right, and you'll come to the nose of Taurus, the Bull.
Taurus's face is a little V shape, and he has long horns reaching far behind his head.
Taurus has a reddish star, Aldebaran (ahl-DEH-buh-rahn). It's the star closest to the top of Orion's shield (the star that marks the top of the bull's face and the bottom of his horn).
Continue past Taurus until you reach a little blurry patch in the sky. That little blurry patch is a cluster of stars known as the Pleiades, or the Seven Sisters. In Japan, the star cluster is known as Subaru (check the car company logo next time you find yourself near a Subaru).
The cluster is made up of hundreds of stars, currently passing through a dust cloud (hence the blurriness).
Most constellations appear the way they do from Earth because of our perspective; if you went to another solar system, they would look completely different. The stars in The Pleiades, on the other hand, are physically near each other in space, so they will look like a cluster from any vantage point.
Draw a line from Rigel to Betelgeuse, and then continue up to Gemini. The stars that make up the heads of the twins are called Castor and Pollux.
The head-stars are very bright, and will likely be one of the only recognizable parts of Gemini when you see it in the sky.
Locate the twins carefully! The two head-stars look an awful lot like Canis Minor if you're only going for an approximation. Shoulders sideways gets you to the little dog, and the Rigel-Betelgeuse line gets you to the twins.
Pollux has really long legs, and Castor has really short legs, so clearly they're fraternal twins.
Lepus, the Hare:
Shhh! I'm hunting wabbits!
Orion, the hunter, needs some prey, and his dogs like to chase things. Follow his dagger downward to find a rabbit, Lepus. It's easy to remember the name of this little guy, because rabbits leap-us.
Never mind that this gigantic lagomorphic monstrosity could probably take out the Little Dog with one well-placed kick of his non-existent legs...
Now you know all of Orion's neighbors!
If you go back to the last lesson, you can see Orion in the photograph, along with Canis Major (everything but the tip of his tail), Canis Minor, and you can even see Pollux's toes (he's the long-legged twin). Lepus is there, too, about to dive nose-first into the Pacific Ocean.
You now have at your disposal two whole patches of sky, and 11 of the 88 constellations, or 12.5% (The Pleiades is considered part of Taurus in the count).
That number becomes even more impressive when you think about all the southern hemisphere constellations you don't have to worry about unless you travel there.