Elma was once a famous astronaut- one of the first women in space, who pioneered the missions to mars that led to the establishment of the first Martian colony after a devastating asteroid struck Earth. However, she always knew her work wasn't finished. Mars doesn't have the resources to support human life forever, and her colleagues spoke continually of the Longevity Mission- a one-way trip someone would have to take to scout the exoplanet where humanity could truly find a new start.

As Elma aged, her opportunities to fly diminished, and now it's been years since she's seen the stars. She stays at home with her dying husband, Nathaniel, watching him slowly waste away from a degenerative disease that will soon take his life. Her first spark of hope in years comes when she receives a call from her old mission leader, Sheldon, asking her to fly again. He wants Elma to embark on the Longevity Mission, undertaking the most important flight of her life. Because of her age, she is a perfect candidate for a trip nobody can return from. However, embarking would mean Elma would leave Nathaniel behind to die alone.

Conflicted, Elma cannot agree to Sheldon's mission- but she can't fully refuse the opportunity of a lifetime either. Nathaniel encourages her to take the mission, as does a kindly doctor, Dorothy, who promises to keep Nathaniel company when Elma cannot in his final days. However, Elma does not agree to the flight until Sheldon calls Nathaniel and asks him to program Elma's rocket. Knowing she will go to the stars surrounded by her husband's code, Elma is finally able to leave behind the man she loves. As she takes flight, she knows Nathaniel is proud of her for the decision.