Solar System lie within a nearly flat disc called the ecliptic. The Solar System also contains smaller objects. The asteroid belt, which lies between the orbits of Mars and Jupiter, mostly contains objects composed, like the terrestrial planets, of rock and metal. Beyond Neptune's orbit lie the Kuiper belt and scattered disc, which are populations of trans-Neptunian objects composed mostly of ices, and beyond them a newly discovered population of sednoids. Within these populations are several dozen to possibly tens of thousands of objects large enough that they have been rounded by their own gravity. Such objects are categorized as dwarf planets.
Mongo (fictional planet) peoples of Mongo have evolved into different forms, such as the winged Hawkmen, the tailed Lion Men, and the underwater dwelling Coralians. Mongo is about half the diameter of Earth but is considerably denser, so its gravity is only slightly weaker than the Earth's, though it still allows Flash Gordon to put his gymnastics skills to good use. Mongo has a variety of climates, and is inhabited by enormous, dinosaur-like monsters. In Alex Raymond's comic strip and the Flash Gordon movie serials, Mongo was shown as a rogue planet that had drifted into Earth's solar system. Later versions of the