AY 102 Lecture Notes - Lecture 4: Copernican Revolution, Orbital Period, Semi-Major And Semi-Minor Axes

• School: University of Alabama
• Department: Astronomy
• Course: AY 102
• Professor: ronald buta

Document Summary

The view of the location of earth in the universe changed from: Six early scientists contributed to these development in astronomy: Ptolemy: famous geocentric model of planetary motion, pla(cid:374)ets (cid:373)o(cid:448)e i(cid:374) (cid:862)(cid:272)ir(cid:272)les o(cid:374) (cid:272)ir(cid:272)les(cid:863) arou(cid:374)d the earth. Brahe: precise observations of planetary positions. Kepler: using these observations, derived three empirical laws of planetary motion, planets move along elliptical paths around the sun. Galileo: using a telescope to discover mountains on the moon, the moons of jupiter, sunspots, and the phases of venus. Newton: using math to derive physical laws of motion and developed the universal law of gra(cid:448)itatio(cid:374) that e(cid:454)plai(cid:374)ed kepler"s la(cid:449)s. What are planets? (cid:862)(cid:449)a(cid:374)deri(cid:374)g stars(cid:863) (cid:272)o(cid:374)stellatio(cid:374)s defi(cid:374)e (cid:862)fi(cid:454)ed stars(cid:863) Seeking evidence that earth is also a planet and that it moves. Two observations favored a heliocentric view: retrograde motion of mars, jupiter, and saturn, venus and mercury can never be seen at midnight.