Astronomy foldable

Revolution The movement of a planet around the sun One revolution around the sun equals one year Planets orbit/revolve around the sun The further away you are from the SUN the longer it will take to make a complete revolution

Rotation The spinning motion of a planet about its axis One complete rotation equals one day This causes night and day to occur You can rotate a basketball on your finger A ballerina rotates when they pirouette

Geocentric Theory A theory that Earth is the center of the revolving planets Geo is the Greek word for Earth This theory was later disproven by Galileo

Heliocentric Theory Earth and the other planets revolve around the Sun Helios is the Greek word for Sun Discovered by Copernicus in the 1500’s Proven to be true by Galileo

Inertia A moving object will continue to move in a straight line and a stationary object will continue to remain in place The more mass an object has the more inertia it has The larger it is the harder it is to start or stop movement

Gravity The force that pulls objects towards each other The strength of gravity depends on the mass of the objects and the distance between them Gravity is what keeps us from floating around in the air

Inertia Gravity Inertia and Gravity Newton figured out that Earth keeps pulling the moon towards it with gravity but the moon keeps moving because of inertia Inertia causes the planets to move in space and the sun’s gravity pulls them towards the sun causes them to move in a orbital pattern Inertia Gravity

Galileo Galileo was a scientist and astronomer He used a telescope to discover Jupiter had 4 moons revolving around it The 4 moons he discovered are Lo, Europa, Ganymede and Callisto. He also discovered that Venus goes through phases like the moon

Galileo His observations help prove the heliocentric system which states that the earth and the other planets revolve around the sun Galileo was tried for heresy because his beliefs went against the church