Chûya Koyama

Mutta Nanba and his younger brother, Hibito, witness what they believe to be a UFO. Hibito decides he will go onto the moon whilst Mutta decides he will aim for Mars. Nineteen years later and Hibito has become a fully fledged JAXA astronaut assigned to go on a mission towards the moon. Mutta has not been so successful in achieving his dreams. The film follows Mutta as he seeks to become an astronaut and join his brother on the moon. (wiki and me)

On a fateful summer night in 2006, Mutta Nanba and his younger brother Hibito witness what they believe to be a UFO flying toward the Moon. This impressing and unusual phenomenon leads both siblings vowing to become astronauts, with Hibito aiming for the Moon and Mutta, convinced that the eldest brother has to be one step ahead, for Mars. (myanimelist.net)