Class B planet

Young planets, Class B worlds are less than 10 billion years old. Their diameters range in size from 1,000 to 10,000 km. They are located in the hotzone region of a star's solar system. Their surfaces are partially molten and may feature active volcanoes with an overall high surface temperature. Their atmospheres, if any, are extremely tenuous, with few active gases. They almost never have life forms.

Examples: Mercury (Sol I), Beta Thoridor I