What happens to Master Chief at the end of Halo 3?
I just finished Halo 3. Towards the end, you see Master Chief sit down, and a bright light surrounds him. His last words are, "We'll make it".
What happened to him? Did he die?
After he says that, the front half of the Pillar of Autumn (with the Arbiter piloting) jumps to Earth, and the back half, along with Master Chief and Cortana, appears to jump to some other location in space. The people on Earth believe Master Chief to be dead, but he survives and goes into cryo-sleep. The final shot of the ending shows that the half of the ship with Master Chief is near/heading towards an unknown planet.
This video shows the ending, starting from the point after he says "We'll make it" and there is a bright flash
More recent information released about Halo 4 reveals that
At some point after these events, Master Chief is awoken from cryo-sleep and they land on the planet. There, he confronts previously unseen creatures and Covenant.