Gravity's Force in Space
Understanding how gravity controls motion in our universe Grade 7 Science - 20 minutes
I Can... Learning Objectives
I can explain what gravity is and how it affects objects in space I can describe how gravity controls the movement of planets and moons I can explain how gravity holds galaxies together I can create models to demonstrate gravity's effects in space
What do you think keeps the Moon from floating away from Earth?
Think about forces you know Consider what might pull objects together Share your ideas with a partner
What is Gravity?
Gravity is a force that pulls objects toward each other All objects with mass have gravity Larger objects have stronger gravitational pull Gravity works everywhere in the universe - not just on Earth The more massive an object, the stronger its gravity
Gravity Well Model Activity
Use fabric stretched over a hoop Place a large ball in the center (represents a planet) Roll smaller balls on the fabric Observe how they move toward the large ball This models how gravity works in space!
Gravity in Our Solar System
{"left":"The Sun's gravity keeps all planets in orbit\nEarth's gravity keeps the Moon orbiting around us\nPlanets closer to the Sun orbit faster","right":"Without gravity, planets would fly off in straight lines\nJupiter's strong gravity captures asteroids and comets\nSaturn's gravity holds its beautiful ring system in place"}
Gravity and Galaxies
Galaxies contain billions of stars Gravity holds all these stars together Stars orbit around the galaxy's center Some galaxies have black holes at their centers Black holes have extremely strong gravity Without gravity, galaxies would spread apart
Success Criteria Check
Can you explain how gravity affects objects in space? Can you describe what keeps planets in orbit? Can you explain how gravity holds galaxies together? Can you create a model showing gravity's effects?