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    What’s Your Sign?
    When people talk about constellations, do you think about the twelve symbols listed in the zodiac? Many people do because it’s fun to talk about astrology. The history of astrology goes back for thousands of years, and there is more than one type of astrology. In some cases the month when you were born is what counts while others rely more on the year you were born. Depending on what year you were born you may be under the sign of the rat or the monkey, or one of the other ten animals. Some people still believe that the date of your birth has an effect on your life. As the earth orbits the sun, several constellations are visible in the night sky for about a month right along the ecliptic circle. The sign in the middle is considered the dominant or main sign. In the monthly astrology, if you were born in the first part of the month of March, Pisces would be your sign. The sun, the moon, and the planets all appear to move through these special constellations during the course of the year. Maybe you have heard of some of the signs like the crab or the twins. If you think you might want to use astrology to predict your future, remember all of the changes that have been made in the calendars over the years. March 5 was probably January 21 thousands of years ago.

    WORDS to KNOW
    ASTROLOGY: Astrology is a belief that stars and other objects in space can be used to predict future happenings or events. People who are born under certain signs are expected to display certain characteristics and qualities.
    What’s a Planetarium?
    Have you ever been to a planetarium? As the lights dim in a large dome-shaped building, the presenter starts the projectors that create the images of the many wonders in space. In some planetariums as the displays change, you can hear the sound of gears moving. Astronomers living around 2,000 years ago used similar gears in some of their simple machines. These machines were used to predict eclipses as they moved the models of the sun and the moon around. Some scientists believe they also showed the paths of the planets. As the show in the planetarium goes along, you soon see the star-filled sky displayed over your head; it changes to show the seasons of the year and the hemispheres on Earth. Going to a planetarium is sort of like climbing into a time machine as it shows you what the sky used to look like and how it might look in the future. You can even experience what it would be like to travel in a spaceship throughout the universe. Wouldn’t it be great to have someone to point out the locations of these different stars when you are in your own yard? Learning where to look for constellations and planets is as simple as taking a trip to the planetarium, buying a planetarium program for your computer, or going on the Internet to look for star maps at Skyan-dtelescope.com .

    WORDS to KNOW
    PLANETARIUM: A planetarium is a special building designed to display all the wonders of the solar system and outer space to an audience.
    Double Trouble
    Did you ever wish that you had a twin? You probably wouldn’t care if they didn’t look exactly like you, as long as they were always there when you needed a friend. Astronomers believe many of the stars have twins. Sirius A, the brightest star in the sky, has a white dwarf companion about the size of Earth, called Sirius B. You might be wondering how astronomers decide if one really bright star is actually two? They look to see if part of the star seems to be blue or coming toward them while the other half is red or moving away. Alpha and Beta Centauri are close enough together to appear as one really bright star, but they are actually triplets if you include Earth’s nearest neighbor, the faint Proxima Centauri. Other binary or twin stars are discovered because once in awhile they eclipse each other just like the moon does the earth.
    Twin Stars

    Can you find the seven differences between this pair of