• Replacement parts, and some glue
• At galactic scale
• Stars, manufacturers of raw material for alive bodies
• Oxygen and carbon start up the life
• Why are oxygen and carbon so important for the living beings?
• Origin of the interstellar dust
• Can the other atoms replace the carbon for the living beings?
• Stars are born together, lifeforms also
• An element of answer to " Fermi's paradox "

We are all extraterrestrials: the galactic origin of the molecules of the alive.

• To the atoms at the organic molecules
• The molecules of primitive solar systems
• Worlds in collision
• Where discovers, in astonishment, a too old life on a too young planet.
• Why did life seem so fast?

Which is alive?

"Our" world : a bacterial world

The life molecules

• polymers, a structure
• Information traffic in the cells
• shape, it is function!
• A strange and very badly known liquid: water
• Metabolism, an energy dynamics
• Reproduction, a fate
• A iconoclast hypothesis: only protein

The origin's theories

• ARN's world
• Abyss
• Our ancestors, the minerals: a " stony dawn " at the dawn of the life
• The invaders
• Life comes moreover...

• Why to limit itself to bacteria?
• Departure point: young solar system
• Dusts, suppliers of organic matter

The polymerisation adventures

• At the surface of the telluric planets...
• In aqueous environment, some peptides forms spontaneously
• In the warm zones, in high pressure...
• In the contact of the various crystals...
• In the atmosphere of jovian planets

Synthesis of nucleic acids

• On and in the interplanetary dusts
• The forming of biologic polymers meets several problems
• How to escape to the fatal dilution?
• But where from comes the ARN?
• How to feed?
• Stony architects are the builders of the life
• Water, a recurring problem
• Emergence of the life is emergence of shape
• The Riboworld
• Detention and reproduction are two connected phenomena
• Portrait robot of the ancestors

Bacteria in space

The solar system, a nutrient broth

• Would Be we all Martians?
• Mars, serious candidate for microbial life
• Allen Hill 's controversy
• Jovian planets, a paradise for light germs?
• Europe, a buried ocean?
• Titan, a world in future...
• Comets, lifes's porters ?

The isobiologic galactic area

• life is a chain reaction at galactic scale
• Has there it other intelligent lifeforms close to us?
• Life and intelligence, contingencies and required
• Underestimated role for the patches tectonic

• The homesickness of matter
• The homesickness of life

Glossary

Bibliography