The Universe contains galaxies, stars, black holes, planets, comets and .
A star is a huge ball of gas, mostly hydrogen and .
Nuclear fusion reactions inside the star release enormous amounts of .
Stars are very hot and give off their own .
This is why we can see the Sun during the day, and distant stars in the sky.
A galaxy is a large group of many millions of .
Our Sun is just one of at least 200 billion stars in our galaxy, the Way.
The observable universe contains around 80 billion .
A black hole cannot be seen because light is unable to from it.
A black hole forms when a large star collapses in on itself because of .
A planet is a large rocky or gaseous object that a star.
Their are almost circular.
Comets are balls of and dust.
Meteors are small rocks. They usually up when they enter a planet’s atmosphere, forming a ‘shooting star’.