science: a way of knowing about the natural world Scientific explanations are based on observations and facts that can be confirmed or disproved by other scientists using accepted scientific techniques.
law: a description of how a natural phenomenon will occur under certain circumstances Kepler's Law of Planetary Motion describes the relationship between the time it takes a planet to go around the Sun and the planet's distance from the Sun.
fact: a natural phenomenon repeatedly confirmed by observation It takes Venus 225 days to go around the Sun.
hypothesis: a possible and testable statement about a natural phenomenon Newton proposed that the force of gravity between two objects depends on the distance between the objects.
theory: a well-substantiated explanation of some aspect of the natural world that typically incorporates many confirmed observations, laws, and successfully verified hypotheses Heliocentricism: the Sun is the center of our solar system.