The Space Sleep Schedule (SSS) is used to help astronauts sleep properly, following a schedule based on their circadian rhythms. Astronauts face the challenge of exhaustion/sleep deprivation, but the SSS builds a schedule around the time astronauts naturally feel tired. Astronauts start by wearing a bracelet made of TPU and powered by a CR2032 coin cell lithium battery, which acts as a sleep actigraph, recording their periods of rest and the times between them for one week. They then plug the bracelet into the corresponding scheduler, made of conductive ABS with a large-sized lithium battery, where it comfortably hugs its curved design and plugs into its sides. Data from the bracelet is transmitted into the SSS. A week-long sleep schedule (displayed on SSS’s electronic screen) is made by mathematically predicting the astronauts’ sleep pattern using data previously recorded from the bracelet. Just about everything except the bracelet face, batteries, and SSS’s screen is 3D-printable.