Lectures in Astrobiology: Vol I (Advances in Astrobiology and Biogeophysics)

3540223150......Page 1
Foreword......Page 4
Acknowledgements......Page 6
Preface......Page 10
Contents......Page 12
1.1 Microfossils......Page 24
1.3 One-handedness of Life......Page 25
2 Reconstructing Life in a Test Tube......Page 26
2.2 Organic Synthesis......Page 27
2.3 Delivery of Organics by Comets and Meteorites......Page 28
2.4 Simulation Experiments......Page 30
2.5 Recreating the Chemistry of Primitive Life......Page 31
3.1 The Diversity of Bacterial Life as a Reference for Extraterrestrial Life......Page 32
3.2.1 Life on Mars and the SNC Meteorites......Page 33
3.2.2 Europa......Page 35
3.3.1 What Are We Looking for?......Page 36
3.3.2 How to Detect Extraterrestrial Life?......Page 37
3.4 Panspermia, Interplanetary Transfer of Life......Page 38
4 Conclusion......Page 39
References......Page 41
1.1 The Ancestors of Solar-like Stars......Page 45
1.2.1 Molecular Clouds and Molecular Outflows......Page 46
1.2.2 T Tauri Stars......Page 47
1.2.3 Protostars......Page 48
1.3.1 Protostars......Page 50
1.3.2 T Tauri Stars......Page 52
1.4.1 Circumstellar Disks......Page 53
1.4.2 High-energy Phenomena: X-ray Emission......Page 55
1.5 X-ray Irradiation: Ionization and Feedback Effects on Circumstellar Disks......Page 60
1.6 Disk Irradiation by Energetic Particles and “Extinct Radioactivities” in Meteorites......Page 62
1.7 The Origin of the Sun, and the Origin of Life......Page 65
The Hertzsprung–Russell Diagram: Stellar Evolution at a Glance......Page 69
References......Page 73
2 Chronology of Solar System Formation......Page 76
2.1 Origin of the Proto-solar Nebula......Page 77
2.2 From Micron-size to Kilometer-size Bodies......Page 78
2.3.1 Formation of Planetary Embryos......Page 80
2.3.2 Formation of the Giant Planets......Page 83
2.3.3 Formation of the Terrestrial Planets and Primordial Sculpting of the Asteroid Belt......Page 84
2.3.4 Origin of Water on Earth......Page 87
2.4 The Future......Page 89
B: Chronology from Radioactivity......Page 92
Specialised......Page 95
3.1 Introduction......Page 98
3.2 The Origin of Water......Page 99
3.3 Formation of the Oceans: the Geological Record......Page 105
3.4 Formation of the Oceans: Chronology and Processes......Page 107
3.5 Chemical Composition of the Primitive Oceans......Page 112
3.5.1 Temperature......Page 113
3.5.2 The pH and the Redox State......Page 114
3.5.3 Salinity......Page 117
Acknowledgement......Page 121
References......Page 122
4 Genesis and Evolution of the Primitive Earth Continental Crust......Page 128
4.1.1 Introduction......Page 129
4.1.2 Age of the Oldest Continental Crust......Page 131
4.1.3 Composition of the Early Continental Crust: Comparison with Modern Continental Crust......Page 134
4.1.4 Source of the Early Continental Crust......Page 139
4.1.5 Mechanisms of Continental Crust Genesis......Page 141
4.1.6 Test of the Model......Page 144
4.1.7 Discussion......Page 147
4.1.8 Summary – Conclusions......Page 148
4.2.1 Introduction: The Archaean Specificity......Page 150
4.2.2 Continental Crust and Earth Cooling......Page 152
4.2.3 Archaean Tectonic......Page 156
4.2.4 Archaean Plate Tectonic?......Page 159
4.2.5 Specificity of Archaean Plate Tectonics......Page 161
4.2.6 The Future of Archaean Continental Crust: Crustal Recycling......Page 163
4.3.1 Episodic Crustal Growth......Page 164
4.3.2 Oceanic-crust Behaviour......Page 167
4.3.3 Archaean Mountains?......Page 169
4.3.4 Cool Early Earth and Late Heavy Bombardment......Page 170
4.4 Main Conclusions......Page 171
Articles......Page 172
2. Specialised......Page 173
5.1.1 Description of the Different Layers......Page 179
5.1.1.1 The Core......Page 180
5.1.1.2 The Mantle......Page 181
5.1.1.4 Lithosphere–Asthenosphere Boundary......Page 182
5.1.2.1 Thermal Balance and Comparison with other Planets......Page 183
5.1.2.2 Plate Tectonics......Page 186
5.1.2.3 Hot Spots......Page 187
5.2.1 Basic Information About Thermal Convection......Page 188
5.2.1.1 Rayleigh–B´ enard Convection: Theory and Limits of its Applicability for the Earth......Page 189
5.2.1.2 The Earth’s Viscosity......Page 192
5.2.2.1 Temperature and Internal Structure of the Earth After Accretion......Page 193
5.2.2.2 Thermal Convection in a Fluid Cooled From Above: Laboratory Experiments and Numerical Models......Page 196
5.2.2.3 Application to the Earth: Cooling and the Onset of Convection......Page 197
5.2.3.1 Temperature Profile of a Convective Fluid......Page 198
5.2.3.3 Coupling Between Thermal Convection......Page 199
5.2.4 Conclusion: a Look at Other Planets......Page 200
5.3.2.1 Convection in the Outer Core......Page 201
5.3.2.2 Solidification of the Inner Core......Page 202
5.3.3 The Magnetic Field of Other Planets......Page 204
References......Page 205
6.1 Geological Evolution of the Early Earth......Page 208
6.1.1.1 Early Fractionation of the Earth’s Crust......Page 210
6.1.1.2 High Heat Flux on the Early Earth......Page 212
6.1.2.1 The Origin of the Volatiles......Page 213
6.1.2.2 Faint Young Sun Paradox......Page 214
6.1.2.4 Oxygen on the Early Earth......Page 215
6.1.2.5 Oceanic Conditions......Page 216
6.2 Potential Early Habitats for Life......Page 217
6.3.1 The Isua Greenstone Belt......Page 219
6.3.2.2 Microbial Mats......Page 221
6.3.2.3 Preservation......Page 222
6.3.2.4 Biogenic Isotopes......Page 224
6.3.2.5 Kerogen and Chemical Biomarker Studies......Page 225
6.3.3.2 Organism type......Page 226
6.4 The Fossilisation of Bacteria......Page 228
6.5 Conclusions and Perspectives......Page 231
References......Page 232
7.1.1 Generalities......Page 240
7.1.2 Lake Vostok: Present Knowledge and Some Open Questions......Page 241
7.1.3.1 The Climate Record......Page 244
7.1.3.2 Chemical Composition of the Glacier Ice......Page 247
7.1.4 Accretion Ice......Page 248
7.1.5 Lake Setting and Possible History of Lake Vostok......Page 254
7.1.6 Ice–Water Equilibrium......Page 256
7.2.1 Underlying Concepts......Page 260
7.2.2 Sketch of the Hypothetical Water-circulation Pattern......Page 263
7.2.3 Energy Balance of the Lake and Water-renewal Time......Page 264
7.2.4 Application to Heat Fluxes and Mass-balance Velocity......Page 265
7.3.1 Constraint on the Geographical Location of the Melting Area......Page 269
7.3.2 The sigma D-sigma^18 O Relationship......Page 274
7.4.1 Previous studies......Page 276
7.4.2 Recent Studies......Page 278
7.4.2.1 Decontamination Procedure and Chemical Controls......Page 280
7.4.2.3 Ice-core Findings with Respect to Contaminant Database:......Page 281
7.4.2.4 Reliable Biological Findings......Page 284
7.4.2.5 The Unclassified Biological Findings......Page 285
7.4.2.6 Deliberations on Biological Findings in Lake Vostok Ice......Page 286
7.4.3.1 Arguments from Geophysics and Ice Geochemistry......Page 287
7.4.3.2 Assessment of Tectonic-fueled Niches or “Biotectonic”......Page 289
7.5.1 Geophysical and Geochemical Aspects......Page 290
7.5.2 Some Lessons for Future Research in Molecular Biology......Page 292
Acknowledgement......Page 294
References......Page 295
8 Comets: Potential Sources of Prebiotic Molecules for the Early Earth......Page 302
8.1.1 The Cometary Nucleus......Page 303
8.1.3 Comet Reservoirs: Oort Cloud and Kuiper Belt......Page 305
8.1.4 The Active Comet......Page 307
8.1.5 Gas and Dust Production......Page 309
8.1.6 Remote Activity, Outbursts and Split Comets......Page 310
8.1.7 Nucleus Modelling: Outgassing and Internal Temperatures......Page 311
8.2.1.1 Observations......Page 313
8.2.1.4 Are Coma Abundances a True Image of Ice Composition in the Nucleus?......Page 317
8.2.1.2 Molecular Abundances in Cometary Ices......Page 314
8.2.2.1 Nature of Grains......Page 318
8.2.2.2 Organics in Grains......Page 320
8.2.2.3 Cometary Silicates......Page 323
8.2.3.1 Elements......Page 325
8.2.3.2 Isotopic Abundances......Page 326
8.2.4 Are All Comets Similar?......Page 327
8.3.1 Experimental Simulations......Page 328
8.3.2.1 UV Irradiation......Page 330
8.3.2.2 Irradiation by Charged Particles......Page 333
8.3.3 Relevance and Importance of Laboratory Simulations......Page 334
8.4.1 Origin of Cometary Matter......Page 335
8.4.2 Cometary Ices versus Interstellar Ices: the Facts......Page 336
8.4.3 Models of Cometary Matter and Comet Nucleus Formation......Page 338
8.4.3.1 Cometary Matter Formation......Page 340
8.4.3.2 The Building of the Nuclei......Page 341
8.4.4 Are Today’s Comets Like Comets in the Early Solar System?......Page 342
8.5.2 Overall Picture of Matter Delivery to the Earth......Page 343
8.5.3 Delivery of elements and Water......Page 345
8.5.5 Do Molecules Survive From Comets to the Earth?......Page 347
8.5.6 Comparison of Comets......Page 348
8.5.7 Chiral Molecules: from the Interstellar Medium......Page 349
8.6 Ground-based and Space Exploration of Comets:......Page 350
8.7 Conclusion......Page 352
References......Page 353
9 Comparative Planetology, Mars and Exobiology......Page 366
9.1 The Study of the Initial Conditions of the Solar System Evolution......Page 367
9.1.1 The Origin of Small Bodies......Page 368
9.1.2 The Impact Rate......Page 370
9.1.3 The Organic Content of Comets......Page 371
9.2 Planetary Energy Sources......Page 372
9.3 The Lunar Records of Solar System Evolution......Page 374
9.4.1 The Global Mars Properties......Page 377
9.4.2 The Major Mars Surface Units......Page 379
9.4.3 The Evolution of the Mars Climate......Page 383
9.4.4 Where Has the Nitrogen Gone?......Page 386
9.4.5 The Martian Meteorites......Page 387
9.4.6 The Present and Future Mars Exploration Programs......Page 388
References......Page 395
10 Spectroscopic Signatures of Life on Exoplanets – The Darwin and TPF Missions......Page 397
10.1 Ozone as a Biomarker......Page 399
10.1.1 O3 as a Tracer of O2......Page 400
10.1.2 The Buildup of a Biogenic O2- Rich Atmosphere1......Page 404
10.1.3 Abiotic Synthesis of O2 and O3 – False- Positive cases......Page 406
10.1.4 Numerical Simulation of O2 and O3 Abiotic Synthesis......Page 409
10.1.5 False Negatives......Page 414
10.1.6 The Detection of an Oxygen-Rich Atmosphere in the Reflected Spectrum......Page 416
10.1.7 Biosignatures on Habitable Planets Around M-Stars?......Page 418
10.2 Others Biomarkers......Page 419
10.3 Temperature and Radius......Page 421
10.4 Other Exo-/Astrobiological Aspects of the Darwin/TPF Missions......Page 427
10.5 Conclusion......Page 428
Elements Concerning the Habitable Zones......Page 429
Specialised......Page 431
Bibliography......Page 435
1.1 From Amphiphilic Molecules to “Protocells” by Understandable Processes. Self-Organisation and Self-Complexification......Page 436
1.2.2 The Structure of Amphiphile-water Mixtures......Page 437
1.3.2 Increased Concentration and Condensation......Page 440
1.3.3 Vectorial Properties......Page 441
1.3.4 Coating the Vesicles......Page 442
1.3.5 Vesicles and Nucleic Acids; Vesicles as Protocells......Page 443
1.4.1 The Modernity of N-Acyl Lipids......Page 444
1.4.2 The Archæal Lipids and Their Synthesis......Page 445
1.5.1 The Problem of the Synthesis of Ingredients......Page 448
1.5.3 The Problem of the Prevalence of Phosphates......Page 449
1.5.4 The Problem of Phosphorylation by Phosphoric Anhydrides......Page 450
References......Page 451
2 Prebiotic Chemistry: Laboratory Experiments and Planetary Observation......Page 456
2.1.1 An Historical View of Miller’s Experiment and the Development of a New Field: Prebiotic Chemistry......Page 457
2.1.2 An Overview of Experimental and Theoretical Data......Page 458
2.1.3 New Scenario for Prebiotic Chemistry......Page 460
2.2.1 Prebiotic Chemistry of HCN: Strecker Reaction or Oligomerization (see Box 2.1)......Page 461
2.2.2 Prebiotic Chemistry of HCHO, Formose Reaction......Page 464
2.3.1 Telluric Planets......Page 465
2.3.2 Giant Planets and Their Satellites......Page 467
2.4 Conclusions......Page 474
References......Page 475
3.1 Chirality: Basic Concepts......Page 479
3.2 Reactivity of Chiral Molecules......Page 484
3.3 Pasteur and the Discovery of Molecular Chirality......Page 485
3.4 Crystals and Crystallization......Page 487
3.5 Homochirality and Life......Page 488
3.6 The Why and When of Homochirality......Page 490
3.7 Origin of Homochirality and Spontaneous Symmetry Breaking......Page 492
3.8 Origin of Homochirality and Parity Violation......Page 495
3.9 Origin of Homochirality and Photochemistry......Page 497
3.10.2 Kinetic Resolution......Page 499
3.10.4 Asymmetric Autocatalysis: Theoretical Models......Page 501
3.10.5 Asymmetric Autocatalysis: Experimental Data......Page 503
3.10.6 On the Possibility to Amplifying Enantiomeric Excesses due to Parity Violation......Page 505
3.11 Exogenous Origin of Homochirality......Page 507
3.12 Hypothesis and Summary......Page 510
3.13 Homochirality Analyses in the Solar System and Beyond......Page 513
References......Page 514
4.1 Introduction......Page 522
4.2 Organic Molecules on the Primitive Earth......Page 523
4.3.1 Exhaustive Survey of Exogenous Amino Acids......Page 524
4.3.2.1 α-Amino Acids......Page 525
4.3.2.2 Non α-Amino Acids......Page 528
4.3.3 Other Meteoritic Compounds Closely Related to Amino Acids......Page 530
4.3.4 Non-Racemic Exogenous α-Amino Acids......Page 531
4.3.6 Conclusion......Page 532
4.4.1 Endogenous α-Amino Acids......Page 533
4.5 Formation Mechanisms of α-Amino Acids and N-Carbamoyl Amino Acids Via Strecker and B¨ucherer-Bergs reactions......Page 534
4.5.1 The Set of Reversible Reactions......Page 537
4.5.2 The Set of Irreversible Reactions......Page 538
4.5.4 Conclusion......Page 540
4.6.1.1 Environment and Reagents......Page 541
4.6.1.2 Suitability of Reactions to Prebiotic Conditions......Page 542
4.6.2.2 Thermodynamic Aspects......Page 543
4.6.2.3 Kinetic Aspects......Page 544
4.7 Convergent Evolution Towards N-Carbamoyl Amino Acids under Prebiotic Conditions......Page 545
4.8 Conclusions......Page 546
References......Page 547
5.1.1 Introduction......Page 551
5.1.2 The Primary Pump......Page 553
5.2.1 Primitive Earth......Page 555
5.2.2 Primitive Atmosphere......Page 556
5.2.3.1 Requirements from the Primary Pump......Page 560
5.3 Investigation of the Primary Pump......Page 561
5.3.1.2 Step (3): CAA Nitrosation......Page 562
5.3.1.3 Step (5): Insights in Peptide Synthesis......Page 563
5.3.2 Integrated Experimental Approach: Chemoselectivity......Page 565
5.4 Energy......Page 567
Acknowledgement......Page 569
References......Page 570
6.1.1 Where in the Living Cell is RNA Found?......Page 574
6.1.1.1 The Three Large Classes of RNA......Page 575
6.1.1.2 Noncoding RNAs (ncRNAs)......Page 577
6.2 An RNAWorld at the Origin of Life?......Page 580
6.2.2 Hypotheses......Page 581
6.2.3 But What do We Know about Primitive Replication?......Page 582
6.3.2 Alternative Genetic Systems......Page 584
6.4.1 Coenzymes and Modified Nucleosides......Page 586
6.4.2 The Case of Adenine......Page 588
6.4.3 Mimicking Darwinian Evolution......Page 589
6.4.4 Other Perspectives......Page 592
References......Page 593
7 Looking for the Most ‘Primitive’ Life Forms: Pitfalls and Progresses......Page 598
7.1 Simpler Doesn’t Necessarily Mean Older!......Page 599
7.2.1 Hyperthermophiles and the Hypothesis of a Hot Origin of Life......Page 600
7.2.2 Hyperthermophiles are Complex Prokaryotes......Page 601
7.2.3 Origin of Hyperthermophily......Page 603
7.2.4 LUCA was Probably not a Hyperthermophile......Page 604
7.2.5 Temperature and the RNA World......Page 606
7.3.1 Simple or Complex LUCA? A RNA or a DNA Genome?......Page 607
7.3.2 A Key Step: the Apparition of DNA......Page 609
7.3.3 Viruses: Essential Players in Evolution......Page 611
7.3.4 The Origin of the Nucleus: a Further Puzzle......Page 612
7.4.2 To not Forget Darwin!......Page 614
Specialised......Page 615
8.1 Principles of Tree-Reconstruction Methods......Page 619
8.2 The Universal Tree of Life According to Woese......Page 623
8.3.1 Multiple Substitutions Generate Reconstruction Problems......Page 626
8.3.2 Mutational Saturation Versus Resolving Power......Page 627
8.3.4 Long-branch Attraction......Page 630
8.3.5 Heterotachy......Page 632
8.3.6 Rare Genomic Events as an Alternative Approach?......Page 634
8.4 Lateral Gene Transfer and the Quest for a Phylogeny of the Organisms......Page 637
8.5.1 The Root of the Universal Tree of Life......Page 639
8.5.2 Prokaryotic Phylogeny......Page 642
8.5.3 Eukaryotic Phylogeny......Page 643
8.6 The Importance of an Evolution by Simplification and by Extinction......Page 645
8.7 Exobiology, a Procession of Extinctions?......Page 648
References......Page 649
9.1 Some Concepts About Extremophiles......Page 658
9.1.2 Some Extremophile Features......Page 659
9.1.3 Why Extremophiles are Interesting?......Page 660
9.2 Microbial Diversity......Page 661
9.3.1 Extremophiles and Extremotolerants......Page 662
9.3.2 Phylogenetic Groups Best Adapted to Extreme Conditions......Page 670
9.3.3 Resistance Forms and Longevity......Page 671
9.4.1 Hyperthermophiles......Page 672
9.4.2 Psychrophiles......Page 674
9.4.3 Halophiles and Evaporites......Page 675
9.5 Perspectives......Page 676
Specialised......Page 677
Erratum......Page 681
1. International System Units......Page 684
2. Other Units......Page 685
4. Fundamental Physical Constants......Page 686
5. Other Physical, Chemical and Astronomical Symbols and Abbreviations......Page 688
6. Periodic Table of Elements......Page 689
1. Units and General Data......Page 691
2. Compared Planetology......Page 692
3. Electromagnetic Spectrum......Page 694
1. General Information......Page 696
2. Decay Constants......Page 697
3. Temperature Range of Magma Emplacement......Page 698
4. Average Compositions of Earth Shells......Page 699
References......Page 703
5. Geological Time Scale and Live Evolution......Page 705
1. The Main Prebiotic Precursors of Biomolecules (in brackets,......Page 706
2. Nucleic Bases......Page 707
3. Nucleosides and Nucleotides......Page 708
4. Amino Acids Genetically Coded......Page 709
5. Peptide Bond Formation......Page 711
A......Page 712
B......Page 717
C......Page 719
D......Page 724
E......Page 726
F......Page 728
G......Page 729
H......Page 731
I......Page 733
L......Page 735
M......Page 736
N......Page 740
O......Page 741
P......Page 743
R......Page 749
S......Page 752
T......Page 756
W......Page 759
Z......Page 760
BIBRING Jean-Pierre......Page 762
BULAT Sergey......Page 763
CRONIN John......Page 764
GARGAUD Muriel......Page 765
LOPEZ-GARCIA Purificación......Page 766
MONTMERLE Thierry......Page 767
OLLIVIER Marc......Page 768
PHILIPPE Hervé......Page 769
SELSIS Franck......Page 770
WESTALL Frances......Page 771
5 Index......Page 772