By John Berry Nasa.gov

A comet is made of ice, dust and frozen gas that makes a tail. A comet takes 200 years to do one orbit around the sun. We now know that comets are leftovers from the dawn of the solar system around 4.6 billion years ago. It also has a nucleus, tail, coma. Bing.com

A comet can go up to 250,000 km/h. A comet spends most of it life on the outer regions of space. A comet is makes meteors when a comet melts some rook or mettle falls and it tunes into a meteor.

From July 16 through July 22, 1994, pieces of an object designated as Comet P/Shoemaker-Levy 9 collided with Jupiter. This is the first collision of two solar system bodies ever to be observed, and the effects of the comet impacts on Jupiter's atmosphere have been simply Comet Shoemaker-Levy 9 consisted of at least 21 discernable fragments with diameters estimated at up to 2 kilometers.

1705: Edmond Halley determines that the comets of 1531, 1607 and 1682 are the same comet and predicts its return in The comet arrives on schedule and is later named Halley's Comet. 1986: An international fleet of five spacecraft converges on comet Halley as it makes its regular (about every 76 years) pass through the inner solar system. smash into Jupiter's atmosphere. Halles comet

What you need to make a comet: Styrofoam balls (1 per kid) Popsicle sticks or plastic straws (1 per kid) Assortment of pompoms, cotton balls, packing "popcorn" or any other small material that can be glued. Pipe cleaners (at least 2 per student) -- Tin foil -- Pillow filling or big pieces of cotton that can be pulled apart -- Clear plastic wrap or cellophane -- Ribbon or any material that can be used as a tail

1. Insert straw or popsicle stick into Styrofoam ball. The ball is the comet nucleus, the stick is merely to hold the comet. 2. Nucleus: Comets have uneven shapes so glue pompons or other materials to the ball so it has an uneven look. 3. Comets are icy so glue or tape pieces of tin foil to the ball. 4. To make the coma, or comet cloud, glue or tape pillow filling, cellophane or plastic wrap around the decorated ball. 5. To create the dust tail and ion tail, push pipe cleaners into ball and/or tape ribbon onto outside of decorated ball.

consists of an orbiter and a lander -- called Philae. The two spacecraft carry 20 science instruments to make a detailed study of comet 67P/Churyumov-Gerasimenko for two years at it approaches our sun.

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