Gravity
Gravity is the thing that pushes us down and gets objects down to the earth so we can use them.
Earth's gravity keeps us on the ground and makes things fall. It pushes everyone down even the strongest people.
Since gravity is attached to the sun and makes our planets go around and around. Gravity is what holds the planets in orbit around the sun. f something is as big as a planet it can catch gravity and lift it like black holes. The reason why birds fly is because gravity doesn't catch them when they get into space. Birds are powered by wings and soft skin.
Gravity has been here from the beginning of time along with the sun.
Planets have the most gravity. Heavier things have more gravity.