Chapter 24- Life in the Universe

What is this?

What is life?

What conditions are necessary?

Water, Carbon, Time

Evidence - Earth

The process:

DNA

Chemistry to Biology where?

EVOLUTION Complexity Survivability

Where should we look?

Search in the Solar System

Europa Surface Close up Interior Search

Mars Water 1 ice ALH84001 ‘The Face’

Extrasolar

      There are LOTS of exoplanets

Habitable zones around planets

Galactic habitable zone

What are the odds?

Drake equation

N = R_star f_planet n_planet f_bio f_intelligence f_{communication} L

Optimists N = .01 L

Pessimists N = 1

SETI

Mostly in radio with bandwidth searchers
None found yet

Earthlike Planet search

Terrestrial Planet Finder what it hopes to find

Why can’t we go there?

Why haven’t we seen them? The Fermi paradox

We are alone.
Interstellar travel is too hard.
zoo hypothesis

Review Questions for Chapter 24