planetary science Planetary science (or more rarely, planetology) is the scientific study of planets (including Earth), celestial bodies (such as moons, asteroids, comets) and planetary systems (in particular those of the Solar System) and the processes of their f ...

, any material that has a relatively high equilibrium condensation temperature is called refractory. The opposite of refractory is volatile. The refractory group includes elements and compounds like metals and silicates (commonly termed rocks) which make up the bulk of the mass of the terrestrial planets and asteroids in the inner belt. A fraction of the mass of other asteroids, giant planets, their moons and trans-Neptunian objects is also made of refractory materials.

Classification

The

elements Element or elements may refer to: Science * Chemical element, a pure substance of one type of atom * Heating element, a device that generates heat by electrical resistance * Orbital elements, parameters required to identify a specific orbit of ...

can be divided into several categories: The condensation temperatures are the temperatures at which 50% of the element will be in the form of a solid (rock) under a pressure of 10⁻⁴

bar Bar or BAR may refer to: Food and drink * Bar (establishment), selling alcoholic beverages * Candy bar * Chocolate bar Science and technology * Bar (river morphology), a deposit of sediment * Bar (tropical cyclone), a layer of cloud * Bar (u ...

. However, slightly different groups and temperature ranges are used sometimes. Refractory material are also often divided into refractory lithophile elements and refractory siderophile elements.

References

Planetary geology Petrology Volcanology Astrobiology Origins Prebiotic chemistry {{astrobiology-stub