Cosmonauts investigate an asteroid belt between Mars and Jupiter. They believe that it might be the remains of a planet. Parallels are drawn to the Greek god Phaethon, who in Greek mythology was the son of the sun god Helios.
| Actor | Role |
|---|---|
 Yuriy YakovlevKosmonavt (voice) | Kosmonavt (voice) |
 Mariya BabanovaDispetcher (voice) | Dispetcher (voice) |
 Nikolay BurlyaevKosmonavt (voice) | Kosmonavt (voice) |
 Aleksey KonsovskiyNot listed | Not listed |
| Nikolay BurlyaevNot listed | Not listed |