Originally posted by: THX
...along with why he went to Krypton (or the empty space where it once was).

Again we have to rely on Singer's backstory here, and/or stuff that was shot but didn't make it.

Per Singer, Lex (while still in prison I guess) managed to get some astronomers to claim or fake that they had found larger remains of the planet Krypton. Again, per Singer's own backstory, upon hearing the news Superman up and left Earth to find it... without telling anyone. And was gone five years because of it. This in a film that is supposedly a quasi-sequel to Superman I and II, the latter of which Superman at the end of the film tells the U.S. President that "Good afternoon, Mr. President. Sorry I've been away so long. I won't let you down again. "

Well except for the fact that I'll bugger off at the drop of a hat to find remains of a planet that my dead father told me, in no uncertain terms, had been blown to smithereens years ago. Nice.

Anyhow, you bring up one of my gripes with this 'quasi-sequel' or as Singer calls it 'vague history' approach- the audience who (gasp) might not be intimately familiar with STM and SII (after 20-30 years) are left at too many points going 'Hunh? WTF? When? How? Why?'.

I think the film's boxoffice results show this. People saw it once, liked it somewhat but not enough to recommend it to their firneds, etc.