What I was writing is that going to the Moon was comparable with life emerging from water.

It's the first time life left the Earth for another celestial body.

So, what could be the next big step? ET life discovery.

However, we don't exactly know what life is. This makes ET life search more complicated.
Besides, we could as well find it in a laboratory on earth as only after a thousand year long trip across interstellar void, or we might never find it as it might simply not exist....We don't know yet.
ET life is marred with huge uncertainties. It is still more a matter of faith rather than facts.