There are approximately 200 billion stars in just our Milky Way Galaxy. Our Sun is one of those stars, with orbiting planets, making up our solar system. Almost every star has it's own solar system of planets orbiting around it.
There's at least 200 billion galaxies, similar to the Milky Way. So, the number of stars in the universe is 200 billion times 200 billion. That's 4 with 22 zeros. This number is hard for the average mind to conceive, but here it is: 40,000,000,000,000,000,000,000.
You'd have to be extremely arrogant to think that we are alone in the universe.
Even if only 1 percent of that large number of stars had planets that could harbor life, that's still 4 followed by 20 zeros. So, the universe has to be full of various life forms, from small organisms to complex life that could be millions of years ahead of us.
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