SETI: Are other intelligent beings out there?

 

Pictures

 
 

Fire?

Viruses?

Prions?

Philosophical / religious implications

Technological implications

Then, Earth, Venus & Mars were similar

Viking Life Detection Experiments

(Liquid water)

(organic compounds)

Carl Sagan in Cosmos and Clarke in 2010 : in atmospheres of Gas Giants ?

Does it need a planet to arise?

Giants.

But stable?

The Drake Equation:

N = R . f_p . n_p . f_l . f_i . f_c . L

R: rate of star formation (~10)
f_p: fraction of stars with planets (opt ~1)
n_p: number of habitable planets per planetary system (1/10)
f_l: probability of development of life (opt ~1)
f_i: probability of developing of intelligence once life started (opt ~1)
f_c: probability of intelligent beings being communicate (~1)
L: Average Lifetime of a technological civilization

⇒ N ~ L

If  L ~ 100, N ~ 100 (even 1 ?)

If L ~ millions, then there are millions of civilizations!

Drake Eqn does not give an answer, it provides a formalism.

Type 1: Can harness all energy resources of a planet

 

Type 2: Can harness all resorces of a star system

 

Type 3: Can harness all resources of a galaxy

too naive?

An intermadiate case: Ringworld, described by Larry Niven

Possibility of ancient life on Mars

Miller - Urey experiment

Electric discharges in a "primitive" atmosphere

→ Organic compounds, including amino acids.

"Where are they?"

- They should be millions of years ahead

 

- With Von Neumann machines, galaxy could be colonized in about a million years

(check the Optional Further Reading)

- So, why haven't they done it?

Suggestion: Effects should be detectable

e.g. a Dyson Sphere : infrared

 

- Not one authenticated case.

- Not fantastic enough

- They should not be so amateurish.

- Maybe the only possible form...

- Dyson Spheres

- Spaceship exhausts?

Explorations: Essay 3: Life in the Universe

• Contact [book] by Carl Sagan

 

In this almost encyclopedic novel, Sagan describes a very plausible scenario of how interstellar contact may occur. The operation of "The Machine" though, is very speculative and smacks quite a bit of Clarke's 2001.



• 2010 [book] by A.C. Clarke

  Description of life on Europa, among other things. The movie was horrible, though.

• Murmurs of Earth [book] by Carl Sagan et.al. (referred to in Topic 17)


• All of Scientific American, Oct.94 (Special Issue "Life in the Universe")


• The Millennial Project: Colonizing the Galaxy in eight easy steps [book] by M. Savage

 
• Life on Mars, an index of new developments (Also referred to above)
• Space Colonization and SETI: A 1979 Interview with Gerard O'Neill
• The Living Universe Foundation, (formerly The First Millennial Foundation, spawned by the third book above)

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