The objective of the Rodent Research-23 mission (RR-23) was to better understand the effects of spaceflight on the eyes, specifically on the structure and function of the arteries, veins, and lymphatic vessels that are needed to maintain vision. To this end, twenty male, C57BL/6J, 16-17 weeks-old mice were delivered to the International Space Station (ISS) on SpaceX-21 in a single transporter, transferred to two rodent habitats, and maintained in microgravity for 38 days. Flight mice were then returned to Earth alive (January 13th, 2021). After splashdown in the Atlantic Ocean, mice were transported to Kennedy Space Center via helicopter. The 20 Flight (FLT), 20 Habitat Ground Control (GC), and 20 Vivarium Ground Control (VIV) mice were removed from Rodent Transporters (FLT and GC) or vivarium cages (VIV), placed into shipping containers, and flown to Texas A and M University. There, mice underwent post-flight procedures, before euthanasia and tissue collection. FLT, GC and VIV animals were euthanized and dissected on Jan 14th, 17th or 20th of 2021, respectively. Soleus muscle samples were preserved by immersion in liquid nitrogen and stored at -80C until RNA was extracted, and libraries generated and sequenced (target 60 M clusters per sample, PE 149 bp). This dataset features 9 samples from the Flight group, 9 samples from the Habitat Ground Control group, and 9 samples from the Vivarium Ground Control group.