Protionaika

Protionaika is a hypothetical astronomical object, a type of planet or moon that is believed to possess a dense, iron-rich core and a relatively thin, volatile-rich mantle. The concept arises from theoretical models of planetary formation, particularly in scenarios where a celestial body forms closer to its star or undergoes significant impacts that strip away its outer layers.

The defining characteristic of a protionaika would be its high density, driven by a proportionally large iron or iron-nickel core. Surrounding this core would be a mantle composed primarily of lighter elements, such as water, methane, or ammonia, which would have either condensed out of the protoplanetary disk or been retained from a later accretion phase. This mantle could be in a solid, liquid, or even gaseous state depending on the temperature and pressure conditions.

The existence of protionaika is not yet confirmed by direct observation. However, astronomers have identified exoplanets with densities that suggest a metallic composition significantly higher than typically expected for rocky planets, leading to speculation about the possibility of such objects. Further research and improved observational capabilities are needed to definitively detect and characterize protionaika if they exist. Their discovery would provide valuable insights into the diverse outcomes of planetary system evolution and the physical processes that shape celestial bodies.