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twin stars?
    Seeing Double?
    Have you ever had a tug of war with your friends? Algol is often called the “demon star” because it is hidden at times by its aging companion star. It almost seems to be playing hide and seek with you. This red giant seems to be losing gas to its brighter twin because of their close orbits! A tug of war between twin stars is not that unusual, and sometimes the winner is not who you would expect it to be. A companion star is often found only by the effect it has on another star. One way to spot them is if they wobble from the pull of the unseen star’s gravity. Could the other star be a black hole? When you go to the planetarium, you might ask if they have to use two projectors to show these binary or “twin” stars. Maybe they will show videos of the real ones!
    Try This
    Star Parties
    Who doesn’t want to be a star? For this party all you need are a few costumes, some sunglasses, a star cake, and a camera. Roll out the red carpet and have a few friends come over for some star trivia, treats, and pictures. Everyone should make a star with their name on it for their own door at home.
    Which One?
    I can make things disappear and reappear simply by doing what I always do.
    Which one am I?
    A. Eclipse
    B. Supernova
    C. Rocket
    D. Comet

    Naming Your Own Star
    The first time you meet someone new, you learn the person’s name. Stargazers like Ptolemy started naming the stars in the sky thousands of years ago to help identify and keep track of them. You might be surprised to know that many of the names the stars are called today came from Middle Eastern astronomers living thousands of years ago. Unfortunately the same star was known by a different name in other places in the world. Modern astronomers started adding Greek letters to the unnamed stars in the newly discovered constellations like some of those in the Southern Hemisphere. They would name the brightest star Alpha, the next would be Beta, and so on until they ran out of stars or letters! This is not a foolproof way to know which are the brightest stars though, because the astronomers didn’t want to change their names even after they found out the stars weren’t quite as bright as earlier astronomers thought they were.
    Some countries have tried naming newly discovered stars after their celebrities, but as you probably have noticed, there aren’t any famous names listed on the star maps. Some astronomers have been honored for their discoveries by having their names used, but the newer stars just have initials that indicate the type of star they are, or numbers, or both. Now, when a star is found it is simply listed by its coordinates on the celestial sphere. If you want to find a new star, looking at catalogs that list the stars may help you. If you look closely, you may see the same star listed with its different names and numbers. Some day you might find a star that no one else has ever found before.
    Try This
    It’s All Greek to Me!
    How about trying something new like learning the Greek alphabet, which is used for many things besides naming stars? You can find it in an encyclopedia or on the Internet by typing in the words “Greek alphabet.” Are there any other alphabets you would like to learn? How about the sign language alphabet?
    Across the Sky
    The word list is here to give you a hand, but be careful— there are two extra words!

    ACROSS
    6. A picture seen ir a pattern of stars
    8. Collections of stars, gas, and dust held together by gravity. The Milky Way is one!
    11. Huge balls of gas that produce light anc heat. Our sun is one!
    12. The Earth's shadow across the moon
    13. Two stars in orbit around each other (2 words)
    DOWN
    1. "Shooting Stars"
    2. A small, icy ball with a iong, glowing tail
    3. The galaxy that hods dut solar systen (2 words)
    4. An exploding star
    5. When the whole face of the moon is lit up (2 words)
    7. The large spheres that orbit around our sun. Sone