Fermi's paradox simplified:
- Earth is 4 billion years old
- Life started 3.5 billion years ago
- We (homo sapiens) arrived about 200,000 years ago
- During the last 50,000 years we became intelligent because of technological innovation (future post)
- We've been traveling to outer space for 50+ years.
- Let's optimistically assume we survive another 10 million years (many species have done this) if we don't ruin our planet (big if).
- We should be able to travel across the galaxy by that point in our timeline
- So, roughly, if the law of averages applies, once life takes root on a planet (or moon), 3.51 billion years later, that life has explored the outer reaches of the galaxy.
- Our galaxy, the Milky Way is 13.2 billion years old
- There are approximately 200 billion stars (solar systems) in our galaxy.
- Our galaxy has had a 9.2 billion year head start on our solar system.
- If life is a natural common occurrence throughout the galaxy, where is everybody?