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Catch a Falling Star

Catch a Falling Star. Yes, The Sky is Falling. In 1957 there was song. Some of the words were:. “Catch a falling star and put it in your pocket, never let it fade away.”. But what is a “falling star” or a “shooting star”? A “falling star” is…. … a meteor!.

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Catch a Falling Star

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  1. Catch a Falling Star

  2. Yes, The Sky is Falling

  3. In 1957 there was song. Some of the words were: “Catch a falling star and put it in your pocket, never let it fade away.”

  4. But what is a “falling star” or a “shooting star”? A “falling star” is…

  5. … a meteor! Where do meteors come from? For that answer, we must look at comets.

  6. Gravity causes comets (dirty snowballs) to hurtle towards the Sun.

  7. As a comet circles the Sun, the heat thaws the ice and rock nucleus. Bits of dust and rock are blown away from the nucleus by the solar wind.

  8. Meteoroids As a comet nears the Sun it leaves a trail of dust and rock, sometimes in clumps and sometimes in a stream. These bits of dust and rock are called meteoroids.

  9. Meteoroids When Earth’s orbit takes us through a clump or stream of meteoroids, our gravity can pull the meteoroids into our atmosphere.

  10. Meteoroids These fragments of Comet Shoemaker/Levy 9 were captured by Jupiter’s gravity.

  11. Three impact sites. A few days later, Two hours later Time At first… nothing Comet Shoemaker Levy 9 broke up into 21 parts before it crashed into Jupiter.

  12. Stray asteroids can also be pulled into our atmosphere by Earth’s gravity.

  13. July 2009’s Impact on Jupiter! Discovered by: Anthony Wesley Australia astro imager Appeared between 17th & 19 July 2009 Similar to impacts by Comet Shoemaker-Levy 9 Has been spotted with as small as a 4-inch telescope. Likely impact from asteroid or comet. Hubble’s new WFC3 was rushed into service to take this closeup of Jupiter’s impact mark on July 23, 2009. Credit: NASA/Heidi Hammel/Jupiter Impact Team

  14. Meteors Once a meteoroid enters our atmosphere, it is called a meteor. But why can we see it? Why does it glow?

  15. What is making this little girl’s hair blow? Why are these 2 guys leaning forward?

  16. “Ram Pressure” If an object moves through air, air directly in front is compressed. When any gas is compressed it heats up. That includes air!

  17. “Friction” Rub your hands together really fast. What happens? Why?

  18. Why do space crafts and space shuttles have heat shields on their bottoms?

  19. Meteors Meteors do not have heat shields. As a meteor falls through our atmosphere, the air in front of it is heated up to more than 3,000° F. Ram Pressure and friction heat makes the meteor glow. This is why we can see it and why most meteors burn up.

  20. Meteors • Most meteors are sand to boulder size particles. • They burn up at altitudes between 60 and 80 miles. • They are only seen for a few seconds. • Almost are all destroyed.

  21. Meteors Billions of meteoroids hit Earth’s sky every day. Only a portion is large enough to be seen as meteors. Meteors with a visible trail are usually no bigger than a bean. Bowling ball sized meteoroids have a better chance of to hit the Earth

  22. Meteors The streak of light that is seen is the material that has burned off. It still glows as it cools off.

  23. Fireballs Very bright meteors are known as fireballs.

  24. Fireballs Fireballs can be as bright as the planet Venus.

  25. Fireballs This fireball was filmed by 14 people.

  26. Bolides A bolide is a meteor that explodes in a bright flash.

  27. Bolides A bolide exploded over Whitehorse, Canada. A “crackling sound,” then a “sonic boom” were heard. Fragments were found.

  28. Bolides Bolide impact in Chesapeake Bay How do we know? The core samples contain Tektites and Shocked Quartz Core Samples

  29. Meteorites Once a meteor hits the ground it is called a meteorite. About 4 ½ thousand meteorites have been found between 1740-1990. This does not include meteorites found in Antarctica.

  30. Largest Meteorite in The U.S. This meteorite weighed 15 tons. It was discovered in 1902 in Willamette, Oregon.

  31. Largest Meteorite in The World The Hoba Iron Meteorite is in the ground in Namibia, Africa. Estimates are that it may weigh 66 tons. Part of it has rusted away.

  32. Micrometeorites Microscopic impact crater found on the Hubble’s camera. Recovered man made satellites sometimes have tiny pits in their metal shells.

  33. Micrometeorites fusion crust pitting and erosion You can find micrometeorites in your own yard or splash blocks for your gutters. They may look like bits of sand, but if you can pick it up with a magnet... most likely it is a meteorite.

  34. Tiniest Meteorites A piece of space dust only 10 microns across. Around 1,000 tons of meteorite dust falls to Earth each day! Image courtesy of NASA

  35. About 85% of all meteorites are chondrites. About 7% are similar to basalts. About 5.7% are mostly iron and nickel. About 1.5% are “Stony Iron”.

  36. Craters The average meteoroid hits our air very, very fast. They slow down a little bit due to the friction. Then they usually burn up. Larger meteoroids slow down very little, hit Earth, and make craters.

  37. XXXXXX XXXX Craters The shock wave upon impact causes fractures in the rock. The central peak of the complex crater is caused by a rebound reaction.

  38. Craters Mistastin Lake, Canada Horseshoe Island is part of center uplift. Manicouagan, Canada Rim diameter: 62 miles One of the largest impact craters preserved on Earth. Ice-covered lake. Photos by Space Shuttle astronauts

  39. Craters The Barringer or Meteor Crater in Arizona is almost 1 mile wide and 570 feet deep. Located 40 miles east of Flagstaff.

  40. Craters Most craters range in size from 90 to 120 miles in diameter.

  41. XXX Dark objects are easier to see on top of snow and ice. ANSMET The Antarctic Search for Meteorites

  42. Shower or Storm? What is the difference between a rain shower and a rainstorm? shower storm

  43. Shower or Storm? The number of drops. shower storm

  44. Shower or Storm? What is the difference between a meteor shower and a meteor storm?

  45. Shower or Storm? The number of meteors.

  46. Shower or Storm When Earth's orbit intersects a meteor stream, the meteor rate is increased and a meteor shower results. A meteor shower typically will be active for several days. An intense meteor shower is called a meteor storm.

  47. Shower 1997 Leonids Meteor Shower from orbiting MSX satellite Seen from above our Earth, meteors create short bright streaks.

  48. Storm These pictures are engravings made after the Leonid meteor storm of 1833.

  49. Radiant As comets orbit the Sun, they shed an icy, dusty debris stream along the comet's orbit. If Earth travels through the stream, we will see a meteor shower. Depending on where Earth and the stream meet, meteors appear to fall from a particular place in the sky, maybe within the neighborhood of a constellation. 2008 September Perseids (not the same as the August Perseids) - Most meteors occurred for a couple of hours beginning at 2 AM. Credit: NASA Meteoroid Environment Office

  50. Radiant The Meteor Shower Radiant Point Our personal perspective makes a meteor “appear” to come from a point in the sky called a “radiant”.

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