1) Heliocentric 2) Important 1) Important 2) Of a lunar crater 3) Of import 
Copernican means of or pertaining to the astronomer Nicolaus Copernicus ...
• (a.) Pertaining to Copernicus, a Prussian by birth (b. 1473, d. 1543), who taught the world the solar system now received, called the Copernican system.
Co·per'ni·can adjective Pertaining to Copernicus, a Prussian by birth ( b. 1473, d. 1543), who taught the world the solar system now received, called the Copernican system. 
[adj] - of radical or major importance 2. [adj] - according to Copernicus
adjective according to Copernicus; `in the Copernican system the earth and other planets revolve around the sun`
of or pertaining to Copernicus or his theories. · important and radically different; thoroughgoing: a Copernican revolution in modern art.