"All thirteen-year-old Houston Stewart has ever wanted is to become an astronaut. His dreams feel like they're finally coming true when he's accepted to the highly-competitive Junior Astronaut Recruitment Program - if only he could bring his little brother, Robbie, with him. Ever since their dad left, Houston and Robbie have been inseparable. It's hard to tell where Houston's love of space ends and where Robbie's begins. But Robbie's cerebral palsy...

When a spaceship carrying Neil Armstrong accidentally time travels to 1869 Texas, cowboy Nat Love decides to trade in his horse for a trip to the Moon, and stepsiblings Abby and Doc must untwist history and get everyone back to their own time.