Stars On Earth is out of Southern Stars (Smart Strike), who won one race in England, over 2000 metres at Sandown as a 3-year-old. Stars On Earth is her second foal and the second to run and win; her half-brother Becrux (Lord Kanaloa) is also a winner. Southern Stars is a half-sister to four other winners, headed by Soul Stirring (Frankel), who took the Gr.1 Japanese Oaks in 2017, and Schon Glanz (Deep Impact), successful in the Gr.3 Artemis Stakes.

Second dam Stacelita (Monsun) was a champion turf mare in America and also a champion in France. Her six Group 1 wins in France and the US include the Gr.1 Prix de Diane, the Grade 1 Beverly D. Stakes, the Grade 1 Flower Bowl Invitational Stakes, the Gr.1 Prix Vermeille, the Gr.1 Prix Saint-Alary and the Gr.1 Prix Jean Romanet.

Third dam Soignee (Dashing Blade) was a Listed winner in Germany and has five winners, the best of them Stacelita. Her half-siblings include Simoun (Monsun), a dual Group 2 winner, and two Listed winners, one of them the dam of Savoir Vivre, a Group 2 winner in France and second in the Gr.1 Deutsches Derby. Another half-sister is the dam of the Group 1 winner Sunny Queen.

Southern Stars' 2-year-old is a colt by Daiwa Major named Stella Del Cielo, and she visited Mikki Isle in the spring of 2021.