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  • There is a vast amount of rocks and debris floating around in space.

  • Around 100 tons of it

  • falls to earth every day.

  • You might have been lucky enough to have seen

  • a shooting star,

  • but do you know what a shooting star is?

  • Is it a comet?, meteorite? Maybe an asteroid?

  • Comet

  • A comet (also called a dirty snowball)

  • is essentially ball of ice,

  • rock and dust that orbits the sun

  • ranging in size from around 1km to 20km.

  • Astronomers believe they are leftovers from the early formation

  • of the solar system that reside in one of two places

  • on the very outskirts of the solar system;

  • The Kuiper belt and the Oort Cloud.

  • These two areas are made up of small icy bodies

  • of frozen gases such as methane, ammonia,

  • nitrogen and water mixed with rock and dust.

  • Occasionally a comets orbit will be altered by a

  • gravitational tug of another large object

  • or through a collision with another body that might

  • send it into the inner solar system

  • or sometimes even straight towards the sun.

  • As a comet starts to move closer the sun

  • it heats up and ice starts to evaporate and form a cloud around the nucleus, called the coma.

  • Two tails form as well, the ion tail and the dust tail.

  • The dust tail

  • is made from the dust forming around the nucleus

  • it is being pushed by solar radiation from the sun

  • following the orbit of the comet

  • The ion tail is generally blue

  • made of ionized gas

  • and points directly away from the solar winds coming from the sun.

  • Asteroid

  • Nearly all Asteroids are odd shaped chunks of rock that orbit the sun

  • n the asteroid belt between mars and Jupiter.

  • The asteroid belt is thought to be either left over mass

  • from a failed planet forming

  • due to the close gravitational pull of Jupiter

  • or the leftovers from a planet that broke up due to a collision.

  • Sizes vary from 10 meters to 1000 kilometers wide

  • Ceres is the largest we have ever found

  • and is 960km wide

  • which is about as wide as Texas

  • and big enough to be classed as a dwarf planet.

  • Some asteroids also have their own moons!

  • Meteoroid

  • Space debris smaller than 10 meter asteroids are called meteoroids.

  • They can be as small as a grain of sand

  • They are usually bits of asteroids that have collided or leftover debris from a comet.

  • When a meteoroid enters earths atmosphere it will hurtle towards Earth

  • as it starts to burn up completely

  • and creates a dazzling trail of light due to the air resistance it encounters.

  • This is called a meteor

  • or as we sometimes call them, shooting stars.

  • When a rock is large enough to survie entry

  • It will end up hitting the Earths surface, usually the size of a pebble.

  • It is then known as a meteorite.

  • The largest ever found is a 3 meter wide

  • 66 ton tablet shape meteorite

  • Found in Namibia, that fell 80,000 years ago.

  • Every year around mid July to mid August

  • the Earth's orbit takes us through the dust and debris

  • left behind by a comet.

  • This is called the Perseid meteor shower

  • and creates an incredible display of shooting stars

  • with around 80 shooting stars an hour.

  • You can find out more about this and how to view the spectacle in the link at the end of the video or in the description below.

There is a vast amount of rocks and debris floating around in space.

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彗星、メテオール、アステロイド - 本当の違い。 (COMET, METEOR OR ASTEROID - The REAL difference.)

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    Summer に公開 2021 年 01 月 14 日
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