How does master chief die

At the end of Halo 3 ( WARNING: this answer contains spoilers if you have not played Halo 3 and wish to.) the Chief and Cortana are seen drifting to an unknown planet after Chief goes into cryo sleep. in other words the game ends with chief surviving and going into cryo sleep until he is needed again, which means he he never died.

but then he would die on the planet from lack of food or he would run out of ammo and get killed by something.
he doesn't. unless you become MC and kill yourself. >_<