Okay well I am going to address at first the theory of life coming from asteroids down to the Earth. The problem I see with this is how was the life created on these asteroids in the first place? It is an impossible task to fully comprehend and understand this as, we as a species, have a limited outlook. But we have this outlook because we are being brought up in a world that is full negative influences and it is not allowing free thinking as much, as the education system tells us this is what is and doesn't allow people to question as much. However, this isn't true for everyone and they are your higher level thinkers but unfortunately they make up a insignificant amount of our population. So from this I got to say that we will not ever know the answers to these questions until, we as a society, learn to let people think for themselves. Next point is on the big bang theory. Yes this is just a theory but it is getting closer to being a reality with every day that goes by as physicists and astrologists are working on studying the universe as we know it. They have already found traces that their had to be a large radioactive occurrence at sometimes as they have found radio waves out in places, and the further they look away the weaker these waves are getting. This is meaning that something has caused these waves to spread and are constantly spreading further out as we speak. But this doesn't mean this theory is true, but it is just a bit of supporting evidence for it. Finally, how do I think we got here? Well that is hard for me to answer, but I believe it was just a series of unlikely events with just the right circumstances that caused us to come into existence, I do not believe in any real theory behind it but I believe it was just pure luck that we have come into existence. I really can not explain this.