Star Wars's Triplets in Alignment with Holst's Mars

It’s already known by many film-music aficionados that parts of John Williams’s score to the 1977 movie Star Wars sound like parts of the 1914–15 orchestral suite The Planets by Gustav Holst. For example, as demonstrated here and here, the buildup to the Death Star explosion repeats forty-six times the same colorful chord that Holst repeats nineteen times at the end of “Mars, The Bringer of War,” which is the first movement in The Planets.

There’s another, more subtle, connection between Williams’s score and Holst’s movement. It’s not surprising that when children sing back the main melody of the “Main Title”…

… they sometimes sing the melody with this different rhythm …

… like here.

They have a good excuse for doing so. Quick triplets are often on weak beats, like pickup beats, instead of strong beats, especially downbeats. Williams’s first triplet follows this convention, but his second one defies it. Children sometimes unknowingly shift the second triplet so that it matches the first and conforms to common rhythmic practice.

Why does Williams put the second triplet on a downbeat? Here’s one among many possible answers: by placing the first two triplets five beats instead of four beats apart, this matches the distance between the two triplets in the rhythmic ostinato from “Mars,” which is in quintuple time: