'“The older brother should always be ahead of the younger one...”

Once upon a time there were two brothers, Hibito and Mutta. Hibito, the littler brother, had been blessed with good luck since the day he was born. Mutta, the elder, had always had bad luck. One day, the two brothers saw a UFO. This experience made them decide to become astronauts. And while Hibito succeeded, Mutta went to work for a car company. Then he caused an incident and had to quit. And then just as Hibito is about to fly to the moon...

When they were little, two brothers, Mutta and Hibito made a promise to each other as they looked up into the night sky. In the year 2025, Hibito has kept his promise and become an astronaut, part of the first wave of people to live for an extended period of time on the moon.

Meanwhile, his older brother Mutta has been fired from his job and is unemployed. But one message from his brother makes him decide to start being an astronaut again.

Thirty two year old Mutta will attempt the astronaut candidate examinations.

To follow his brother Hibito to the moon, Mutta will attempt to become an astronaut at the age of 32. Unaware of his own talent, elder brother Mutta chases his dreams to get back in front of his younger brother.
Believing the words “The older brother should always be ahead of the younger one...”

雑誌『モーニング』で2008年より連載開始され、講談社漫画賞と小学館漫画賞をW受賞。2012年には小栗旬&岡田将生共演による実写版映画も公開される小山宙哉原作の『宇宙兄弟』が、満を持してのTVアニメ化。『あの日見た花の名前を僕達はまだ知らない。』で、芸術選奨新人賞メディア芸術部門を受賞したA-1 Pictures が制作を手がけ、監督は劇場版「ドラえもん」シリーズの渡辺歩。声の出演は、兄・六太に洋画吹き替えのベテラン、平田広明、弟・日々人にアーティスト兼俳優としても活躍するKENN。宇宙への夢と憧れに加え、綿密な科学考証、詳細な取材でSFファンのみならず幅広い層に愛されているリアリティに満ちた HOW to 宇宙飛行士物語。