My God, I just spent half of the last night debating this on Facebook -.-<p>My takeaway from that experience - when someone struggles with understanding why those two views are both equivalent and OK, make sure they understand this thing: heliocentric and geocentric models have only one purpose. They let you compute where planets will be at any given time. They do <i>not</i> try to answer <i>why</i> the planets are moving the way they are. For that, you need at least Newton&#x27;s model of gravity, which actually doesn&#x27;t differentiate between the Sun and planets at all.<p>Geocentric models still pop up in real life. When you&#x27;re using a sky map to determine where some planet will be visible tonight, you&#x27;re looking at a geocentric representation.