You may know it as Space Melody by Luna Park or as ResuRection by ППК (English: PPK), but the original melody was composed by Eduard Artemyev for the 1979 Soviet film Siberiade. The original name of the song, as titled in the movie’s soundtrack release, is la mort du héroes (the death of heroes, if my French is correct).
Here’s a link to the original composition, if you’re curious.
Your French is pretty close. “héroes” should be written “héros”, there’s no “e” and “du” means “of the” singular. So The Death of the Hero .
But the héroes thing might be misspelled in the ost itself.