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                  YOU CAN SEE MORE STARS   IN THE COUNTRY  On a clear, moonless night using just your eyes,  about 300 stars are visible from the city, and  about 1,000 in a darker small-town sky. In the  darkest countryside about 3,000 are visible; use  binoculars and you’ll see more than 40,000.  Why do some   stars shine   brig















             ADHARA   Epsilon CMa  Part of Canis Major,    Sirius (or the “Dog Star”)    is the brightest star in the    sky, burning 20 times     brighter than the sun.




             POLLUX   Beta Gem


             BETELGEUSE   Alpha Ori ALL THE BRIGHTEST STARS IN THE  NIGHT SKY ARE LABELED ALPHA  Stars are named within a constellation in order of  brightness using the Greek alphabet, so the brightest stars  begin with alpha, the next brightest with beta, and so on.  Many of the stars we can see also have historical names,  such




             SIRIUS   Alpha CMa                                Betelgeuse in the   Orion constellation     is one of the top     ten brightest stars     in the night sky.  Seen in Earth’s  Southern Hemisphere,  Scorpius has a sting in   its tail, killing Orion    in Greek mythology.  Stars in    a constellation    are close togeth













       FAST FACTS  EACH STAR   THE BIG DIPPER IS CONSTANTLY   50,000 years ago  MOVING   THE BIG DIPPER  IN SPACE  Today Stars are constantly moving in Earth’s sky, but it takes  tens of thousands of years before new positions are  noticeable and constellations have new shapes. Yet it is  possible to see changes since the ancient













   US_308-309_309600_Astronomy.indd   308                                 19/12/17   3:50 pm
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