1. ASTROBIOLOGY IS THE STUDY OF LIFE ACROSS THE UNIVERSE. PARTICULARLY: 1.The Origins of Life 2.The Distribution of Life 3.The Destiny of Life ASTROBIOLOGY

2. IDENTIFICATION OF LIFE THE TRADITIONAL CHARACTERISTICS OF LIFE INCLUDE Respiration Digestion Elimination Reproduction Motility Sensation

3. MAJOR LIFE CATEGORIES ON EARTH Anaerobic Aerobic

4. ESSENTIALS OF COMMON LIFE ON EARTH Anaerobic Aerobic

5. EXTREMOPHILES Water >70% Acidity pH 4-8 Substrate Viscosity (cP=1) Atmospherics c 7-35 lbs/in^2 O2 = c 20% CO2 = 3ppm Toxic-tolerant Metals Non-Metals Temperature 0-100 C max 15-60 C optimal Environmental range of common life on earth… Range for >80% of earth life Extremophiles Familiar Xenophiles Unfamiliar Transitional Near-Life or Life-Like ECOSYSTEMS Fringe for <20% of earth life

6. THE GOLDILOCKS THEORY 0 The occurrence of life at a given place in the universe is a statistical probability. It can be expressed in terms of “Drake’s Equation” The Drake equation states that: N=R* x fp x ne x fl x fi x fc x L where: N is the number of civilizations in our galaxycivilizations with which we might expect to be able to communicate at any given time, and R* is the rate of star formation in our galaxystarour galaxy fp is the fraction of those stars which have planetsplanets ne is average number of planets which can potentially support lifelife per star that has planets fl is the fraction of the above which actually go on to develop life fi is the fraction of the above which actually go on to develop intelligent life fc is the fraction of the above which are willing and able to communicate L is the expected lifetime of such a civilization

7. THE RATE OF STAR FORMATION (R*) 0 5 10 15 2.5 Origin of Milky Way Galaxy Sol 1 2 N … Detecting life may require searching planets which had life in the past (1,2), or will develop life in the future (3). Detecting life may require searching planets which had life in the past (1,2), or will develop life in the future (3). Life may be nascent and ‘yet-to-form’, or deceased, ‘long-since-gone’ 20 B I L L I O N Y E A R S

8. THE GOLDILOCKS THEORY 1 Too Hot Too Cold Just Right G O M Given Drake’s Equation, we hope to find common life in Habitable Zones comparable to Earth’s common life forms. 273K 373K Liquid H2O

9. THE GOLDILOCKS THEORY 2 Too Hot Too Cold Just Right G O Giant Stars M Dwarf Stars We also look for Habitable Zones compatible with Earth’s Extremophiles 273K 373K Liquid H2O Moons of Jupiter & Saturn Gas Giant Planets can create geologic interior gravitational tides which heat the moons thru ocean venting.

10. THE GOLDILOCKS THEORY 3 Too Hot Too Cold Just Right G O Giant Stars M Dwarf Stars 273K 373K Liquid H2O In addition, anomalies can create Habitats outside recognizable habitable zones. Terrforming

11. LIFE’s PROGRESSION ON EARTH Archean Eoarchean Era (3800 mya) Prokaryotes Achaeans Anaerobic bacteria Paleoarchean (3600 mya) Aerobic bacteria Mesoarchean Stomatolites Neoarchean Proterozoic Proto-Proterozoic (1800 mya) Complex single-celled life Neo-Proterozoic (630 mya) Multiple celled organisms sustain an oxygenated atmosphere … Phanerozoic Paleozoic (412 mya) Life moves to land (terra firma) H2 bonds w/ gases from volcanoes; the atmosphere is predominantly greenhouse gases NH3, CH4 & H2O w/ others Life starts terraforming earth; adding O2 & N2 The atmosphere is predominantly N2, O2 and H2O w/ CO2 NH3 (Ammonia) CH4 (Methane)O2 CO2 N2 Achaean Life Begins Aerobic Life Begins The Atmosphere Is in Continuous Transition Nitrogen Cycle Oxygen Cycle THE ATMOSPHERE Life on Earth is in symbiosis with the atmosphere …

12. LIFE & ITS ECOSYSTEMS 1 Autotrophs Food Producers Heterotrophs Food Consumers Saprotrophs Food Decomposers Biogenic Elements Continuous Source of Energy Continuous Source of Energy UV Wave Protection UV Wave Protection Gaia hypothesis suggests life can be detected on a planetary scale By tell tale signs, biomarkers or other indicators. Markers of Life include Waste gases such as Methane gas or other organic materials; Waste alcohol; Regenerated gases, e.g. O2 Seasonal color changes

13. QUESTIONS 1 How did life begin? Is it planetary on-site, or Panspermic? Physiosphere Biosphere Noosphere Replication Organic Compounds Molecules Microbial Cells Metabolic Activity Biochemical Reactions Sentient Thought & Awareness Instinctive Behavior Photo-Chemical Response Elements Hydrogen Atoms Nuclear Particles Dark Matter Singularity The Evolutionary Process The essential Elements of life, The Biogenics The Energy The UV Protection have been found on Planets in our Solar System, planetary discs beyond our solar system, and in galactic compositions, beyond the Milk Way…

14. QUESTIONS 2 Common life forms Found on earth … Common life forms Found on earth … Given evolutionary potential for extremophiles, how is life distributed across the Universe? Given evolutionary potential for extremophiles, how is life distributed across the Universe? ? Bacteria EukaryotesAchaeans Is evolution necessarily parallel for life everywhere?

15. QUESTIONS 3 What is the fate of life in the universe? Biosphere Noosphere Replication Organic Compounds Molecules Microbial Cells Metabolic Activity Biochemical Reactions Sentient Thought & Awareness Instinctive Behavior Photo-Chemical Response Elements Hydrogen Atoms Nuclear Particles Dark Matter Singularity The Evolutionary Process ??????? Physiosphere ???????