Today is Copernicus Day, but what is it?
Every year on February 19 scientists across the world celebrate Copernicus Day. Learn about the man who changed how we view ...
BBC2y
Changing ideas about the Solar System
An Egyptian astronomer called Ptolemy (AD100-168) described one of the earliest ideas for how the Solar System is structured. Ptolemy’s model and many earlier ideas of the Solar System had the ...