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  • What causes a falling star? - NASA
    StarChild Question of the Month for August 1999 Question: What causes a "falling star"? Answer: A "falling star" or a "shooting star" has nothing at all to do with a star! These amazing streaks of light you can sometimes see in the night sky are caused by tiny bits of dust and rock called meteoroids falling into the Earth's atmosphere and burning up The short-lived trail of light the burning
  • StarChild: Meteoroids - NASA
    The chance of seeing a meteor with the unaided eye increases after midnight People often refer to meteors as "falling" or "shooting" stars The brightest of the meteors are called fireballs Sonic booms often follow the appearance of a fireball just as thunder often follows lightning At certain times of the year, more meteors than normal can
  • What causes fireballs in the sky? - NASA
    Fireballs were much in the news over the past month due to a big one that was seen in the Illinois, Michigan, and Indiana areas around local midnight on March 26 - 27, 2003 The fireball streaked across the sky and exploded in a bright flash But just what causes the fireball, and how often do they occur?
  • Star Art - NASA
    Star Art - An Introduction to Myths of Different Cultures Star watching has occupied humans from the earliest times Our ancestors studied the night sky and saw shapes and patterns among the stars They often made up stories to explain what they saw The same star constellation was seen very differently by people from different countries, or even different parts of the same country When
  • StarChild: Comets - NASA
    Scientists believe that comets are the debris left from the solar nebula which condensed to form the Sun and planets in our solar system Most comets are thought to originate in a huge cloud called the Oort Cloud The Oort Cloud is believed to surround our solar system and reach over halfway to the nearest star, Alpha Centauri, which is 150,000 astronomical units away Scientists think that
  • Are all stars in a galaxy? - NASA
    The observations show that the motion of the individual star is governed by the gravitational field of the cluster as a whole, rather than the pull of any one galaxy In other words, they are truly "intergalactic", or between galaxies Astronomers had expected the existence of intergalactic stars
  • Why do stars twinkle? - NASA
    To our eyes, this makes the star seem to twinkle You will notice that stars closer to the horizon will appear to twinkle more than other stars This is because there is a lot more atmosphere between you and a star near the horizon than between you and a star higher in the sky Go out some night soon and have a look!
  • How can the Sun burn? - NASA
    This heating eventually grows out from the center (or core) of the star to the outside, finally leaving the surface and radiating out into space to be the heat and light we know stars emit People, including scientists, sometimes say that the Sun "burns hydrogen" to make it glow But that is just a figure of speech
  • 88 Officially Recognized Constellations - NASA
    Return to the StarChild Main Page Go to Imagine the Universe! (A site for ages 14 and up )
  • How long does it take to fly to Saturn? - NASA
    The nearest star (after our Sun, of course!) is Proxima Centauri at a distance of 4 2 light years At a speed of 17 km sec (such as what the Voyager 1 spacecraft currently has), it would take about 75,000 years to reach Proxima Centauri





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