Details
Cobalt (Jetto),a defective prototype of Astro built by Dr. Tenma, is released from storage and becomes Astro's older brother.
- Genres: Animation, Mystery, Sci-Fi & Fantasy, Kids
- Language:  Japanese
Cast & Crew
- Cast:Mari Shimizu , Kazue Tagami , Youko Mizugaki , Akihiko Mitsueda , Seizô Katô , Shingo Kanemoto , Kiyoshi Komiyama , Masaaki Yajima
- Creator: Osamu Tezuka
- Producer: Osamu Dezaki, Osamu Tezuka