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.