• generation of the geomagnetic field, which can be investigated
through realistic numerical simulations of the core dynamo,
combined with recently available satellite and paleomagnetic data,
and
• origin and evolution of the inner core and its role in the core
dynamo, as revealed by the strong seismic heterogeneity and
anisotropy discovered in the past few years.
6. Planetary science, which uses extraterrestrial materials, as well as
astronomical, space-based, and laboratory observations, to investigate
the origin, evolution, and present structure of planetary bodies,
including the Earth. Telescopic observations of primitive objects in the
solar system and of the planets orbiting distant stars are beginning to
furnish unique data regarding the origin and evolution of the solar
system. Current and planned space missions will provide
unprecedented detail and coverage of the geology, topography,
structure, and composition of many solar-system bodies. Within a
decade, the first samples collected from Mars, a comet, an asteroid,
and the Sun (via solar wind particles) will be returned to Earth for
direct investigation. A proper interpretation of these data will require
the application of Earth-science techniques and appropriate terrestrial
comparisons. Such comparisons promise improved understanding of
the Earth and solar system as a whole:
• Other planets furnish new environments for investigating the basic
geological and geophysical processes operating on and within the
Earth.
• Most planets preserve physical and chemical records of the early
solar system that contains data on planetary evolution that no longer
exists on Earth.
• Distinctive chemical and isotopic signatures from extraterrestrial
samples are critical for furthering the understanding of the mixing,
accretion, and differentiation of meteorite parent bodies and planets,
including the Earth.
PRINCIPAL FINDINGS AND RECOMMENDATIONS
EAR has done an excellent job in maintaining the balance among core
programs supporting investigator-driven disciplinary research, problem-focused
programs of multidisciplinary research, and equipment-oriented programs for new
instrumentation and facilities. The committee offers recommendations that
address the evolving science requirements in all three of these programmatic
areas. These recommendations pertain primarily to new mechanisms that will
allow EAR to exploit research opportunities identified by the committee.
EXECUTIVE SUMMARY
5
About this PDF file: This new digital representation of the
original work has been recomposed from XML files created
from the original paper book, not from the original
typesetting files. Page breaks are true to the original; line lengths,
word breaks, heading styles, and other typesetting-specific
formatting, however, cannot be retained,
and some typographic errors may have been accidentally inserted.
Please use the print version of this publication as the authoritative
version for attribution.
through realistic numerical simulations of the core dynamo,
combined with recently available satellite and paleomagnetic data,
and
• origin and evolution of the inner core and its role in the core
dynamo, as revealed by the strong seismic heterogeneity and
anisotropy discovered in the past few years.
6. Planetary science, which uses extraterrestrial materials, as well as
astronomical, space-based, and laboratory observations, to investigate
the origin, evolution, and present structure of planetary bodies,
including the Earth. Telescopic observations of primitive objects in the
solar system and of the planets orbiting distant stars are beginning to
furnish unique data regarding the origin and evolution of the solar
system. Current and planned space missions will provide
unprecedented detail and coverage of the geology, topography,
structure, and composition of many solar-system bodies. Within a
decade, the first samples collected from Mars, a comet, an asteroid,
and the Sun (via solar wind particles) will be returned to Earth for
direct investigation. A proper interpretation of these data will require
the application of Earth-science techniques and appropriate terrestrial
comparisons. Such comparisons promise improved understanding of
the Earth and solar system as a whole:
• Other planets furnish new environments for investigating the basic
geological and geophysical processes operating on and within the
Earth.
• Most planets preserve physical and chemical records of the early
solar system that contains data on planetary evolution that no longer
exists on Earth.
• Distinctive chemical and isotopic signatures from extraterrestrial
samples are critical for furthering the understanding of the mixing,
accretion, and differentiation of meteorite parent bodies and planets,
including the Earth.
PRINCIPAL FINDINGS AND RECOMMENDATIONS
EAR has done an excellent job in maintaining the balance among core
programs supporting investigator-driven disciplinary research, problem-focused
programs of multidisciplinary research, and equipment-oriented programs for new
instrumentation and facilities. The committee offers recommendations that
address the evolving science requirements in all three of these programmatic
areas. These recommendations pertain primarily to new mechanisms that will
allow EAR to exploit research opportunities identified by the committee.
EXECUTIVE SUMMARY
5
About this PDF file: This new digital representation of the
original work has been recomposed from XML files created
from the original paper book, not from the original
typesetting files. Page breaks are true to the original; line lengths,
word breaks, heading styles, and other typesetting-specific
formatting, however, cannot be retained,
and some typographic errors may have been accidentally inserted.
Please use the print version of this publication as the authoritative
version for attribution.