Our Galaxy By: Julia Loisel
How big is a comet, might you ask? well, As a comet gets closer to the sun, the ice particles on it's nucleus vaporize and form a cloud called a "Coma". the Coma forms around the nucleus that can be 50,000 miles wide. Comet tails form as the comet gets closer to the sun. they can be over 600,000 miles long.
But what is a comet made of, might you also ask? well, Comets are made of ice, small rocky particles, and frozen gases such as Carbon Monoxide, and carbon Dioxide. sometimes Comets are called"Dirty Snowballs".
But where do they come from? good question. Comets originate from the Kuiper Belt. Danish astronomer Jan Oort proposed that comets reside in a huge cloud at the reaches of the solar system, far beyond Pluto, or Pluto's orbit. this cloud is called the Oort cloud.
this is the Oort cloud.
this is a comet and what looks to be the North Star.
an asteroid is made of metals, mostly. it is made up of 80% iron, 20% nickel, iridium, palladium, platinum, gold, magnesium and others such as osmium ruthenium and rhodium.
Asteroids mostly just float along in the Asteroid Belt. but where do they come from?
Some asteroids have orbits close to Earth. They are very big. In fact, the Chicxulub crater under the Yucatan peninsula in Mexico is the result of an asteroid impact that might have wiped out dinosaurs.y
this is Ceres, the biggest known asteroid.
Meteors are made up of dust and ice from the trail of comets. meteors can be "stony", and this means that they are made up of minerals rich with silicon and oxygen, "iron" consisting mostly of iron and nickel, or "Stony- iron", a combination of the two.