DSST Astronomy - Deck 1 Practice Questions and Answers

Parallax An apparent shift in a star's position relative to the stars around it. This perceived shift is caused by motion on Earth's surface as it rotates around the sun. Scientific Method An ordered process for discovering new knowledge that relies on observation, explanation, prediction, and experimentation. Occam's Razor A problem-solving principle that says the simplest solution to a problem is most likely to be correct. Theory A testable prediction based on real-world observations. Ptolemaic Model An early rendering of the universe that placed a perfectly spherical version of Earth at its center Heliocentric Model An early rendering of the universe that placed our Sun at the middle instead of Earth. Galilean Moons The moons of Jupiter, which were originally mistaken for planets. Kepler's First Law Planets orbit in elliptical patterns with the sun at their center. Kepler's Second Law A line connecting any planet to the sun would sweep over equal areas in equal amounts of time. Kepler's Third Law The square of a planet's orbital period is proportionate to the cube of the semi-major axis of its orbit. Newton's First Law An object at rest or in movement will remain at rest or in movement unless acted upon by an outside force. Newton's Second Law The sum of all forces on an object is equal to the object's mass times its acceleration.