The great contribution of Tycho Brahe was to
A) observe planetary positions with sufficient accuracy that later enabled Kepler to discover the laws of planetary motion.
B) discover four moons orbiting Jupiter, thereby lending strong support to the idea that the Earth is not the center of the universe.
C) offer the first detailed model of a Sun-centered solar system, thereby beginning the process of overturning the Earth-centered model of the Greeks.
D) discover that planets orbit the Sun in elliptical orbits with varying speed.
Question 2
Massive-star supernovae and white-dwarf supernovae work equally well as standard candles for measuring cosmic distances.
Indicate whether the statement is true or false
