Wolowitz is caught in an argument between Bernadette and his mom, even while he's in space. Meanwhile, with his friends on dates, Raj feels lonely.
As Howard awaits blast-off, he recounts how the gang threw together a last-minute wedding for him and Bernadette.
When Stephen Hawking visits Caltech to give a lecture, Sheldon goes to great lengths for a chance to meet his hero in person.
Sheldon incurs Amy's ire when he chooses a weekend of videogaming with the guys over a birthday party for her aunt.
Sheldon is forced into altering his precious schedule after his barber falls ill. Meanwhile, the training required to be an astronaut has Wolowitz wondering if he has the right stuff.
Leonard can't take Sheldon's continued selfishness and agrees to dissolve the Roommate Agreement. Howard wants to have a cool nickname for when he's an astronaut.
Sheldon finds himself in hot water when he doesn't appreciate Amy's recent accomplishment. Howard discovers Bernadette doesn't interact well with children.
Sheldon is miffed that Leonard plans to attend a party hosted by his nemesis, Wil Wheaton. Meanwhile, Howard is offered a chance to be a payload specialist on the International Space Station.