Dr. John Mather, a Project Scientist for the James Webb Space Telescope, answered questions on Reddit in an "Ask Me Anything" today.
One question Mather tackled was on common misconceptions about outer space.
Mather explained that people vastly underestimate how big outer space really is, and that most of it is vast pockets of emptiness. The immense distance between planets, suns, and galaxies would make it improbable for aliens to land on Earth, at least in a timely manner.
Mather writes:
There's a lot of talk about space aliens as though it were physically possible for them to get here from somewhere else, and (sorry to say this) talk about human travel out of the solar system. We just don't live long enough to do that.
So much for seeing E.T. in our lifetime.
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