The oldest American settler, a farmer and botanist who maintains the algae farm, forming a grandfatherly bond with Bell. Known for his kindness and humor, he is a passionate advocate for cooperation.

Commander of the United States Mars Settlement, responsible for leading the group of settlers with a caring, practical approach. Despite initial mistrust, he is deeply concerned for his community and respected by others.

A 14-year-old boy and Bell's best friend, who initially becomes distant in his desire to be seen as more mature. He seeks the Commander’s approval and learns the value of teamwork and rekindles his friendship with Bell.