A powerpoint I did for a speech in an astrobiology course.

1. Sam Kiesinger – Astronomy 310

2. If there is other intelligent life in the universe,
why haven’t we seen clear evidence of it yet?
The Fermi Paradox
Enrico Fermi - 1950

3.  200 billion stars in the milky way
 Anywhere from 100 to 500 billion galaxies
 Life chemicals are not “unique” to our solar
system
 Terrestrial planets while not as common as
Jovian do not appear to be “exceptionally
rare”

4. Statistically intelligent life should exist
somewhere in our universe
Why haven’t we heard from it?

5.  Intelligent life might be so rare and sparsely
distributed we might as well be alone
 Intelligent life might self-destruct thanks to
survival of the fittest instinct
 Destructive natural phenomenon may wipe
out life. Impacts, super novae, etc.
 There are too many paths to the argument
“we are alone” to cover

6. We got here late

7.  Median age of terrestrial planets is 1.8 GA
greater than earth
 If evolution remotely resembled earth’s there
may be civilizations 1.8 GA older than ours

8.  The oldest art is around 35,000 years old
 The advances between then and 1900 were
astonishing
 Due to the exponential growth of technology
1900 to 2000 accomplished more than the
previous 35,000(powered flight to landing on
the moon in 66 years)
 The next 100 years will accomplish more still

9.  35,000 years is 0.0000175% of 2 GA
 To visualize this stack 5 pennies next to the
Empire State Building. That’s how far along
this timescale we are
Not to scale

10.  Despite natural or intelligence-made
disasters as long as a viable genetic group
remains they have time to bounce back and
overtake us many times over.
 Their technology and even existence today
may be far beyond our current
comprehension of the physical universe
“Any sufficiently advanced technology is indistinguishable from magic.”
-Arthur C. Clarke

11.  Much of our efforts to listen for intelligence
has been radio waves. A technology just
under a century old
 More advanced races may use wholly
different technologies for communicating

12.  Freeman Dyson theorized a race may surround its star
with artificial constructs to make total use of the light
and heat emitted
 GAs of “free” power
 Reduce the odds of discovery by other civilizations
 Could theoretically create livable space orders of
magnitude greater than a planet
 The search for “Dyson Spheres” and their signatures
should be considered as important as radio signals
 We know this is viable technology, “Space Based
Solar” is already being developed by our civilization;
that is the

13.  Planetary formation and evolution did not
cease 1.8 GA ago but we may have missed
the peak of civilizations developing
concurrently with ours
 We may still find species that we can
communicate with and perhaps someday
visit but the odds are smaller now if this
theory is correct