Entries beginning with "Timeline of " are ordered by the rest of their names. (For example: Timeline of geology is listed under "G".)
Further, timelines containing extra wording before the key concept are indexed under the key concept. (For example: Timeline of discovery of Solar System planets and their moons is listed under "S".)
For information on how to reorder entries to adhere to this rule, please see this Categorization FAQ entry and/or view the relevant [[Category:...]] tag in one of the reordered entries.