Terra incognita refer to the hypothesized continent Terra Australis Incognita ("The unknown land of the South"), as seen in the Theatrum Orbis Terrarum map by Abraham Ortelius (1570). During the 19th century "terra incognita" disappeared from maps of the earth, since both the coastlines and the inner parts of the continents had been fully explored. But the bottoms of the seas remain mostly un-mapped, as do many other land surfaces in the solar system. The phrase is now also used metaphorically by various researchers to describe any unexplored subject or field of research. For more history of the terms, see Terra Australis,
Planet Master Super Villains. The first Planet Master uses weapons based on the planets. The second Planet Master could simulate the conditions typical to any of the nine planets in our solar system. For example, he can use the speed of Mercury, the heat of Mars, the strength of Jupiter, the rings of Saturn, and the cold of Pluto. Planet Master appears in the "" episode "Aquaman's Outrageous Adventure," voiced by Stephen Root. Although he has the appearance of the Irving Norbert version of Planet Master, his powers are similar to the second Planet Master. While stopping in a Western theme-park town