Did we not directly pass the galactic equator back in the 90s? Or am I wrong?

We do that every year on the same date.

No, we have too many laws, medicines and surgeries now. Natural selection only works half of the time.

Basically McDonalds

Incorrect. Pure oxygen facilitates a high rate of combustion. Pure oxygen does not under normal circumstances combust.
You would need some sort of fuel source, hydrocarbons or hydrogen (some metals can oxidize violently as well such as magnesium, commonly used in fireworks).
You see, combustion is an example of an oxidation reaction (other oxidation reactions are those which occur in batteries, or the rusting of metals). Oxygen cannot oxidize itself, and thus, if you were to strike a match in a pure oxygen environment, it would burn violently for a very short period of time (due to the sulfur and other fuels on the matchstick) and then go out.

I'm sorry but I think I stated that wrong. I didn't mean to say it spontaneously combust but when you have a balloon full of pure oxygen and put a flame source next to it then it burns rapidly. That's why old people with oxygen tanks go boom when they smoke cigarettes. I may not understand what you're trying to say but to my understanding you're saying you need more compounds in the mixture in order to create an oxygen fueled explosion. I'm very interested in chemistry.