Published in "Fundamentals of Cosmic Physics", Vol. 19, pp. 319-422, 1998.

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Observations of the Magnetic Fields Inside and Outside the Solar System: From Meteorites (~ 10 attoparsecs), Asteroids, Planets, Stars, Pulsars, Masers, To Protostellar Cloudlets (< 1 parsec)

Jacques P. Vallée


Herzberg Institute of Astrophysics, National Research Council of Canada,
5071 West Saanich Road, Victoria, B.C., Canada V8X 4M6


Abstract. Moving outward from the Earth, one first observes magnetism in older well-formed stars and planets, then one observes magnetism in advanced protostellar disk systems, and one ends inside very young starforming cloudlets (it is akin to moving from old to young star systems). This review covers a range in magnetic field strength from 10-6 Gauss up to 1015 Gauss. I review here our observational knowledge of magnetic fields in interplanetary, stellar and starforming spaces, surveying meteorites (~ 0.3m or 10 attoparsecsin size; 1 parsec = 3.1 × 1016 m = 3.2 light-years), asteroids (~ 30 km or 1 picoparsec), planetary realms (~ 1 nanoparsec), interplanetary space (~ 1 microparsec), circumstellar space (~ 1 milliparsec), protostellar systems (~ 1 centiparsec), out to interstellar starforming cloudlets (up to ~ 1 parsec in size). Spacecrafts from Earth have measured in situ the magnetic field shapes and strengths just outside several planets, moons, and asteroids, as well as the general ubiquitous interplanetary magnetic field. Telescopes on Earth have performed measurements of the magnetic field strengths and shapes in circumstellar environments, protostellar disks, and interstellar cloudlets. Magnetic processes are essential to a detailed understanding of their internal physics and evolution. On small scales, active dipolar dynamo-type magnetic fields can play a dominant role in the dynamics of gas and dust around compact objects. Published theories in protostellar disks and starforming cloudlets are classified along physical parameters. There is little here on the magnetism of objects with sizes > 1 parsec (magnetism on scales > 1 parsec was reviewed in Vallée, 1997).


Key-Words: Magnetic fields; solar system magnetism; stellar system magnetism; magnetized stars; remanent magnetism; masers; protostellar magnetism; magnetic field and star formation; dynamo magnetism; quantum magnetism; magnetized protostellar cloudlets.


Table of Contents

INTRODUCTION
Man-made Magnetism
Natural Magnetism
Aims of this Review

MAGNETIC FIELDS IN SMALL BODIES: METEORITES, COMETARY NUCLEI, ASTEROIDS, MOONS, PLANETS
Remanent Magnetism
Dipolar-shaped Magnetic Field
Magnetic Moment and Angular Momentum

MAGNETIC FIELDS IN STARS AND IN THE INTERPLANETARY MEDIUM
Sun (~ 106 km; ~ 10-7 pc) (~ 10 Gauss)
Spiral-shaped Interplanetary Magnetic Field (~ 108 km; ~ 10-6 pc) (~ 10-5 Gauss)
Normal Stars (~ 106 to 107 km; ~ 10-7 pc)
Degenerate Stars, White Dwarfs (~ 2000 km) (~ 106 Gauss)
Neutron Stars (~ 10 km)

CIRCUMSTELLAR MAGNETIC FIELDS (OUT TO 200 AU; ~ 10-3 PC)
Cataclysmic Binary Objects (~ 105 km) (~ 106 Gauss) and Polars (~ 6 × 107 Gauss)
Late-type Variable Giant Stars (~ 108 km), Young Stars
Double Stars and Symbiotic Stars (~ 1010 km; ~ 10-3 pc)
Masers at Centimeter and Millimeter Wavelengths (~ 109 km; ~ 10-4 parsec)
Circumstellar Gas (out to ~ 3 × 1010 km; ~ 0.001 pc)

METHODOLOGY AND INSTRUMENTATION FOR PROTOSTELLAR AND INTERSTELLAR DETECTION
Basic detection concepts at Radio, Extreme IR, Far IR, and Mid IR Wavelengths
Instrumentation at Long Infrared Wavelengths

PREDICTED MAGNETIC FIELDS IN PROTOSTELLAR DISKS (OUT TO ~ 2000 AU OR SO; ~ 10-2 PARSEC) AND DENSE INTERSTELLAR STARFORMING CLOUDLETS (0.1 TO 1 PC)
Distinctions of sizes
Magnetic Fields and Star Formation Onsets
Collapse models
Magnetic Disk Classes
Expected B with Time
Other Theoretical Ideas

OBSERVED MAGNETIC FIELDS IN PROTOSTELLAR DISKS (OUT TO ~ 200 AU OR SO; ~ 10-2 PC) AND DENSE INTERSTELLAR STARFORMING CLOUDLETS (0.1 TO 1 PC)
Excess line width for small objects (sizes < 1 parsec)
Magnetic Field Strengths
Polarization Percentages and Physical Parameters
Polarization Position angles and Physical Parameters
Some Mapping Results So Far ( 10-3 Gauss)
Many Unanswered Questions

STRIPES AND CLOUDLETS AT NEAR-INFRARED, OPTICAL, AND ULTRAVIOLET WAVELENGTHS (~ 10-6) GAUSS)
Gas Stripes near Planetary Nebulae
Cloudlets in Filaments
Diffuse Interstellar Dust Near and in between Stars

CONCLUSION

REFERENCES

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