The Movie Timeline - it's like a timeline, but of movies
Superman - timeline
The planet Krypton explodes.
According to Lois Lane's article, "I Spent the Night with Superman", Krypton explodes - baby Kal-El spends the next four years in a space ship while travelling to Earth. (Krypton)
Kal-El arrives from Krypton. (Smallville, Kansas)
A spaceship crashes carrying a strange visitor from another world. (nr Smallville, Kansas)
Superman appears for the first time. (Metropolis)