Contents -- Foreword -- Preface -- 1. General Introduction -- 1.1. Historical Perspective -- 1.2. Discovery -- 1.3. Appearance -- 1.4. Statistics -- 1.5. Importance -- 1.6. Brightness -- 1.7. Main Characteristics -- 1.8. Spacecraft Encounters with Comets -- 1.9. An Overall View -- Problems -- References -- 2. Dynamics -- 2.1. Orbital Elements -- 2.2. Orbit in Space -- 2.2.1. Relevant equations -- 2.2.2. Orbital elements from position and velocity -- 2.2.3. Orbital elements from observations -- Problems -- References -- 3. Physical Aspects -- 3.1. Black Body Radiation -- 3.2. Perfect Gas Law -- 3.3. Dissociative Equilibrium -- 3.4. Doppler Shift -- 3.5. Spectroscopy -- 3.5.1. Atomic spectroscopy -- 3.5.2. Molecular spectroscopy -- 3.5.3. Chemical subgroups -- 3.6. Isotopic Effect -- 3.7. Franck-Condon Factors -- 3.8. Intensity of Emitted Lines -- 3.9. Boltzmann Distribution -- 3.10. -Doubling -- 3.11. Photochemistry of Water -- 3.12. Silicate -- 3.13. Annealing -- 3.14. Carbon -- 3.15. Solar Radiation -- 3.16. Solar Wind -- Problems -- References -- 4. Spectra -- 4.1. Main Characteristics -- 4.2. Forbidden Transitions -- 4.3. Line-to-Continuum Ratio -- Problems -- References -- 5. Spectra of Coma -- 5.1. Fluorescence Process -- 5.1.1. Rotational structure -- 5.1.2. Vibrational structure -- 5.1.3. Comparison with observations -- 5.1.4. Case of C2 molecule -- 5.1.5. Prompt emission lines of OH -- 5.1.6. Molecules other than diatomic -- 5.1.7. OH radio lines -- 5.1.8. Oxygen lines -- 5.1.9. Forbidden transitions -- 5.1.10. Molecular band polarization -- 5.2. Excitation Temperature -- 5.2.1. Rotational temperature -- 5.2.2. Vibrational temperature -- 5.3. Abundances of Heavy Elements -- 5.4. Isotopic Abundances -- 5.5. Summary -- Problems -- References -- 6. Gas Production Rates in Coma -- 6.1. Theoretical Models -- 6.1.1. From the total luminosity.

6.1.2. From surface brightness distribution -- 6.1.3. From number densities -- 6.1.4. Semi-empirical photometric theory -- 6.2. Results -- 6.2.1. OH and H -- 6.2.2. H2O, H2 -- 6.2.3. CN, C2, C3, NH -- 6.2.4. CH, NH2 -- 6.2.5. CO, CO2 -- 6.2.6. CS, S2 -- 6.2.7. Ions -- 6.2.8. Complex molecules -- 6.2.9. O, C, N, S -- 6.3. Analysis of Hydrogen Observations -- 6.3.1. Analysis of Lyman measurements -- 6.3.2. Analysis of H observations -- 6.4. Related Studies -- 6.4.1. Gas-phase chemistry in the coma -- 6.4.2. In situ mass spectrometer for ions -- 6.4.3. Temperature and velocity of the coma gas -- 6.5. Parent Molecules -- 6.6. Chemical Diversity -- 6.7. Summary -- Problems -- References -- 7. Dust Tails -- 7.1. Dynamics -- 7.2. Anti-tail -- 7.3. Dust Trails -- 7.4. Sodium Gas Tails -- 7.5. Dust features -- Problems -- References -- 8. Light Scattering Theory -- 8.1. Mie Scattering Theory -- 8.1.1. Effciency factors -- 8.1.2. Albedo -- 8.1.3. Scattered intensity -- 8.1.4. Polarization -- 8.2. Approximate Expressions -- 8.3. Computation of Cross Sections -- 8.4. Results -- 8.5. Particles of Other Types -- 8.6. Optical Constants -- Problems -- References -- 9. The Nature of Dust Particles -- 9.1. Visible Continuum -- 9.1.1. Albedo -- 9.1.2. Phase function -- 9.1.3. Dust production rate from continuum -- 9.1.4. Dust production from A( )f -- 9.2. Polarization -- 9.2.1. Linear polarization -- 9.2.2. Circular polarization -- 9.3. Grain Sizes -- 9.4. Infrared Measurements -- 9.4.1. Dust production from infrared observations -- 9.4.2. Anti-tail -- 9.5. Spectral Feature -- 9.5.1. Silicate signature -- 9.5.2. Mineralogy of dust particles -- 9.5.3. The C-H stretch feature -- 9.5.4. Ice signature -- 9.6. Properties Derived from Direct Measurements -- 9.7. Radiation Pressure Effects -- 9.8. Summary -- Problems -- References -- 10. Ion Tails.

10.1. Evidence for the Solar Wind -- 10.2. Dynamical Aberration -- 10.3. Theoretical Considerations -- 10.3.1. Comparison with observations -- 10.4. Instabilities and Waves -- 10.5. Acceleration of Cometary Ions -- 10.6. Large Scale Structures -- 10.6.1. Tail rays or streamers -- 10.6.2. Knots or condensations -- 10.6.3. Oscillatory structure -- 10.6.4. "Swan-like" feature -- 10.6.5. Bend in the tail -- 10.6.6. Disconnection events -- 10.7. X-rays -- 10.8. Summary -- Problems -- References -- 11. Nucleus -- 11.1. Morphology -- 11.2. Theory of Vapourization -- 11.3. Outbursts . -- 11.4. Albedo and Radius -- 11.5. Mass, Density and Surface Gravity -- 11.6. Rotation -- 11.7. Nucleus Composition -- 11.8. Mass Loss -- 11.9. Structure -- 11.10. Non-gravitational Forces -- 11.11. Ortho to Para Ratio of Molecules -- 11.12. Binary Systems -- 11.13. Summary -- Problems -- References -- 12. Origin -- 12.1. Evidence for the Oort Cloud -- 12.2. Evolution and Properties of Oort Cloud -- 12.2.1. Short period comets -- 12.3. Origin of the Oort Cloud -- 12.4. Taxonomy -- 12.5. Summary -- Problems -- References -- 13. Relation to Other Solar System Studies -- 13.1. Asteroids -- 13.2. Meteorites -- 13.3. Meteor Streams -- 13.4. Particles Collected at High Altitudes -- 13.5. Primordial Material -- 13.6. Chemical Evolution -- 13.7. Terrestrial Water -- 13.8. Impact of Outside Bodies -- 13.9. Overview -- Problems -- References -- 14. Problems and Prospects -- 14.1. Epilogue -- 14.2. Future studies -- Index.