ASTRO 7N - Unit 2 questions with answers 2024/2025

ASTRO 7N - Unit 2Copernicus - correct answer proposed the heliocentric (sun-centered) model of the universe, which replaced the geocentric (earth-centered) model distance between earth and sun - correct answer 1 astronomical unit -1 AU time for earth to orbit sun - correct answer 1 earth year -365 days Kepler's first law - correct answer the planets orbit the sun in elliptical orbits with the sun at one focus -these ellipses tend to be nearly circular for the planets in our solar system Kepler's second law - correct answer a line joining a planet and its star sweeps out equal areas during equal intervals of time -or, a planet's speed is fastest when the planet is closest to the sun (perihelion) and slowest when it is farthest away (aphelion_ perihelion - correct answer point when the earth is closest to the sun aphelion - correct answer point when the earth is farthest away from the sun Kepler's third law - correct answer P^2 = a^3 -P is the orbital period (a planet's year, given as a multiple of earth years) -a is the semimajor axis (average distance from sun, given in AU mercury - correct answer -can only see close to Sun and it is hard to do with the naked eye -displays phases