There is almost certainly life elsewhere than Earth. I'd say a 99.999999% chance. In fact, it may be within our own solar system. Jupiter's moon Europa has warm, liquid water beneath its outer ice layer. Besides, there could be life that has evolved to non-Earth-like conditions.
That is 2 places in our own solar system that could have Earth-like life. Scientists have discovered over 500 solar systems in our own Milky Way Galaxy with more being discovered all the time.
Hubble has discovered over 100 billion galaxies, and that is only what we can see so far.
We are not alone, we are not special. That is all.
Edit: Saying we are alone because we haven't discovered life yet is as egotistical as saying Earth is the center of the universe.
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The universe is infinitely expanding. New planets, solar systems, stars, and entire galaxies are made every second. Time is infinite. There is infinite time for new planets to take the place of the old ones. Somewhere, sometime, life will have to exist beyond earth.