helio-, heli- +
2. Having to do with or based on the heliocentric theory.
This replaced the earlier geocentric (earth-centered) system described by Ptolemy (c. A.D. 100-170).
Ptolemy was a Greek philosopher who presented a widely accepted model of the solar system known as the "Ptolemaic system". He also made important contributions to geography and cartography.
The "Ptolemaic system" was a theory developed by Ptolemy, about A.D. 150, maintaining a motionless earth is the center of the universe with sun, moon, and planets revolving, around it; while the fixed stars are attached to an outer sphere concentric with the earth. This model was generally accepted in the West until the establishment of the "Copernican theory" about 1500 years later.
Nicolaus Copernicus (1473-1543), is the Latinized version of the name Mikolaj Kopernik, the Polish astronomer who established the heliocentric model of the solar system; that is, the principle that the sun (not the earth) is the central point to which the motions of the planets are to be referred.
Copernicus was recognized as the first person in history to create a complete general arrangement of the solar system (Copernican system); combining mathematics, physics, and cosmology.