Brianna (Roxanne in the Japanese version) is a prospective astronaut in the Astro Boy 2003 series. She is a very intelligent student, and was Astro's first crush She only appears in episode 36, "Space Academy."
Brianna is a highly skilled and intelligent student at the space academy. She first met Astro when she saved him from Anton's loose fireball, which she disabled on a second's notice by identifying one of its power cords. Astro visited the academy to help design the Horace 2 rocket's guidance system, and Brianna was very impressed with Astro when considering his age. She finds him cute and treats him like a little brother, but still maintains a polite and formal tone with him.
Brianna is passionate about the Horace rocket project, and is eager to talk to Astro about it. She was accepted as one of the first astronauts to go on it to space. Brianna is primarily focused on her studies and research, particularly with rope theory and time theory. She is an introvert and does not have a lot of close friends outside of her studies. She has been ridiculed for her studies into transcending time, and feels a great bond with anyone who takes her seriously.
Both Anton and Astro have romantic feelings for her. Anton uses Astro as help in writing Brianna a love letter and giving him things to say during a meeting with Brianna. However, she is hurt and feels cheated when she finds out the truth. In the end, she proceeds on with her mission to space, staying single but still remaining friends with Anton and Astro.