Lyric discussion by georgy 

The question "Is there life on mars?" is, I think, like saying "Is this the best we can do? Help! Stop the world I want to get off!" I think he wrote it as a stream of consciousness. maybe not...

I agree, tells the story of a innocent girls who is disappointed and yearns for something else.

A 'scream' of consciousness, perhaps?

@georgy You are entirely correct, and I am afraid all other (lengthy) explanations are wrong.

Bowie actually gave an interview about writing this song, stating it came to him after a group of sailors got into a fight in a park, where he was one morning. He took the bus back to his studio and composed.

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