PSCH

• GEOCENTRIC MODEL - A MODEL OF UNIVERSE WHICH CONSIDER EARTH AS THE CENTER OF THE UNIVERSE.
• HELIOCENTRIC MODEL - A MODEL OD THE UNIVERSE WHICH ASSUMES THE SUN AS THE CENTER OF THE UNIVERSE.
• ARISTOTLE - BELIEVED THE EARTH IS MOTIONLESS AT THE CENTER OF THE UNIVERSE AND ALL THE STARS AND PLANETS MOVED IN CIRCULAR PATHS.
• JOHANNES KEPLER

  • Mathematician
  • Tycho's assistant.
• LAW OF ELLIPSES - THE ORBITS OF THE PLANETS ARE ELLIPTICAL.
• LAW OF EQUAL AREAS - AN IMAGINARY LINE CONNECTING A PLANET AND THE SUN SWEEPS OUT EQUAL AREAS DURING EQUAL TIME INTERVALS.
• LAW OF PERIODS - SHOWED THE RELATIONSHIP BETWEEN THE SIZE OF A PLANET'S ORBIT RADIUS
• ISAAC NEWTON - EXPLAINED WHY PLANETS ORBIT THE SUN, AND WHY MOON ORBITS THE PLANETS
• GALILEO GALILEI - FIRST PERSON TO USE TELESCOPE FOR  ASTRONOMICAL OBSERVATIONS.
• TYCHO BRHAHE - FAVORED AN EARTH - CENTERED UNIVERSE DIFFERENT FROM PTOLEMY'S THEORY.
• PTOLEMY - PLANETS TRAVELLED IN CIRCULAR PATHS AS THEY TRAVELLED AROUND THE EARTH.
• PYTHAGOREANS - BELIEVED THE STARS, PLANETS, SUN AND THE MOON WERE ATTACHED TO THE CRYSTALLINE SPHERES WHICH ROTATED AROUND THE EARTH.
• GEOCENTRIC - EVERYTHING MOVE AROUND THE EARTH