Themis family

Lore & Background

The Themis family is a collisional family of C-type asteroids, with a composition believed to be similar to that of carbonaceous chondrites. It consists of a well-defined core of larger bodies surrounded by a region of smaller ones. The family is named after its parent body, 24 Themis, which was discovered on 5 April 1853 by Italian astronomer Annibale de Gasparis. Asteroids in the Themis family share orbital elements with semimajor axes between 3.08 AU and 3.24 AU, orbital eccentricities between 0.09 and 0.22, and orbital inclinations of less than 3°.

Reader's Guide

The Themis family is significant as one of the largest and longest-recognized dynamical families of asteroids, comprising over 4700 known members. Its carbonaceous composition, similar to carbonaceous chondrites, provides insight into the early solar system's material. The family's well-defined core of larger bodies surrounded by smaller ones reflects its collisional origin. The parent body, 24 Themis, discovered in 1853, anchors the family. The family's orbital parameters—semimajor axes from 3.08 to 3.24 AU, eccentricities from 0.09 to 0.22, and inclinations under 3°—define its members. The Themis family's legacy lies in its role as a benchmark for studying asteroid family dynamics and the composition of primitive solar system bodies.

Did You Know?

• 24 Themis was discovered on 5 April 1853 by Annibale de Gasparis.
• The family has over 4700 known members.
• Its asteroids are C-type, similar in composition to carbonaceous chondrites.