© 2007 Jones and Bartlett Publishers Chapter 2 2-6 thru 2-10 From an Earth-Centered to a Sun-Centered System Courtesy of NASA/JPL-Caltech.
Astronomy190 - Topics in Astronomy Astronomy and Astrobiology Lecture 2 : History of Science & Astrobiology Ty Robinson.
Vocabulary: Special Difficulties “Critical English” Secondary 6 Atthawut Trakitthornkul.
