Rules for Capitalizing Scientific Terms and Geological Eras
1. Names of planets and their satellites, asteroids, stars, constellations, and groups of stars and other celestial objects are capitalized; however, the words sun, earth and moon are usually lowercased unless they occur with the other astronomical names.
Examples: Venus; Ganymede; Sirius; Pleiades the Milky Way: probes heading for the Moon and Mars
2. Genera in binomial (two-word) scientific names in zoology and botany are capitalized; names of species are not.
Examples: a cabbage butterfly (Pieris rapae); a common buttercup (Ranuculus acris); a robin (Turdus migratorius)
3. New Latin names of classes, families, and all groups above genera in zoology and botany are capitalized; however, their derivative adjectives and nouns are not.
Examples: Gastropoda but gastropod; Thallophyta but thallophyte
4. Geological eras, periods, epochs, strata, and names of prehistoric divisions are capitalized.
Examples: Silurian period; Pleistocene epoch; Age of Reptiles; Neolithic age