MoscowCassiopeia Russian is a Soviet 1973 film directed by Richard Viktorov based on a script by Isai Kuznetsov and Avenir Zak. Followed by Otroki vo vselennoy second part, 1974. Runtime 85 min.
The project is all carefully thought out but student Fyodor Lobanov stows away aboard the starship and unwittingly causes it to transcend the speed of light and so reaching its targetyears ahead of schedule...
Source: Wikipedia