Eyeball planet

Common card · No. 387317

An eyeball planet is a hypothetical type of tidally locked planet (one side of the planet faces permanently its star), and such tidal locking induces spatial features (for example in the geography or composition of the planet) resembling an eyeball in the case to contain enough liquids. They are terrestrial planets where liquids may be present, in which tidal locking will induce a spatially dependent temperature gradient (the planet will be hotter on the side facing the star and colder on the other side). If this temperature gradient includes temperatures over the freezing point, it could avoid a snowball state or becoming an ice planet, so that there could be areas in which liquid may exist on the surface of the planet to ring- or disk-shaped areas (then the circular liquid or terrestrial region present under the substellar point, would be like the iris of a human eye, being the frozen part like its white or sclera part). Such planets are further divided into "hot" and "cold" types, depending...

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