Geocentric model fire being lighter than air. Beyond the layer of fire, were the solid spheres of aether in which the celestial bodies were embedded. They, themselves, were also entirely composed of aether. Adherence to the geocentric model stemmed largely from several important observations. First of all, if the Earth did move, then one ought to be able to observe the shifting of the fixed stars due to stellar parallax. In short, if the Earth was moving, the shapes of the constellations should change considerably over the course of a year. If they did not appear to move, the stars are either
Mahazat as-Sayd Protected Area species of gazelles, the idmi and dorcas gazelle. It is likely that striped hyenas and cheetahs once also inhabited the area. Mahazat as-Sayd Protected Area The Mahazat as-Sayd Protected Area is a 220,000 ha large protected area in central Saudi Arabia. The area is totally fenced and protection from livestock grazing has allowed a spectacular recovery of native vegetation. The reserve is now dominated by grasslands, which are a reminder of what most of the Arabian peninsula may have looked once. Mahazat as-Sayd is one of the few places where the Arabian oryx has been reintroduced. In addition the reem