Solar and Space Physics Space Science in the Twenty-First Century -- Imperatives for the Decades 1995 to 2015 (1988) / Chapter Skim
Currently Skimming:
3. Status Expected in 1995
3. Status Expected in 1995
Pages 17-32
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 17... ...
However, if our most optimistic expectations of the progress of these projects and their subsequent analysis were justified, we would be only beginning to investigate the possible variation of these properties through the activity cycle. The specification of the solar interior properties from helioseismological techniques will provide crucial new input into models of 17
|
From page 18... ...
To study and understand these processes (for example, changes in magnetic field strength, waves, single pulses, and systematic mass flows) , it will be necessary to resolve spatial scales over which significant gradients occur in the local magnetic and nonthermal velocity fields, as well as in the local densities and temperatures.
|
From page 19... ...
Significant progress can be expected in two areas of study involving rrucroscopic plasma processes in the interplanetary medium. Continued theoretical work on the problem of heat conduction and viscosity In a thermally driven stellar wind not dominated by Coulomb collisions should advance to the point where lack of in situ observations of the inner solar wind would prevent further progress.
|
From page 20... ...
These magnetospheres have sufficiently different internal parameters and boundary conditions to allow testing of the universality of basic magnetospheric concepts. The solar wind interacts with planetary magnetic fields to produce diverse phenomena that involve the storage and energ~zation of charged particles.
|
From page 21... ...
A common theoretical framework has been developed so that when account is taken of differing conditions within the various magnetospheres, radio emissions in one planetary magnetosphere can be related to that in another as different manifestations of the same physical process, although the frequency ranges of the emissions might be quite different. The Terrestrial Magnetosphere as a System The International Solar Terrestrial Physics Program will acquire simultaneous measurements throughout key regions in order to understand the behavior of the system as a whole.
|
From page 22... ...
The four CLUSTER spacecraft will provide detailed information on localized current systems and magnetohydrodynamic processes, and SOHO will yield additional information on interplanetary and solar phenomena that can affect the terrestrial magnetosphere. These ISTP measurements will allow us to develop an understanding of the physical processes occurring in the solar-terrestrial environment.
|
From page 23... ...
The dynamic~ of the magnetosphere and thermosphere are coupled through field-aligned currents, electric fields, Joule heating, and particle precipitation, which both heats the upper atmosphere and alters the electrical conductivity of the ionosphere. Before the end of this decade, this multipronged study of thermospheric dynamics is expected to lead to significant advances in our understanding of the energy and momentum sources controlling atmospheric motions in these altitude regions.
|
From page 24... ...
Thermospheric coupling includes studies of the particle and solar inputs and corresponding middle atmospheric responses on a global scale. Finally, the important question of the coupling of the troposphere and the middle atmosphere will be a central component of the field as a whole; anthropogenic perturbations to the atmosphere in general and the ozone layer specifically will continue to be an important central theme for middle atmospheric studies.
|
From page 25... ...
The details of the telluric currents flowing in both the solid earth and oceans are complex and require comprehensive experimental and theoretical investigations. The problems associated with the global electric circuit cut across numerous disciplines, from magnetospheric convective processes at one end to soil and ocean conductivity issues at the other encI.
|
From page 26... ...
If a body has no strong magnetic field but does have an atmosphere, two other interactions can occur, whose effects are sometimes difficult to separate. First, if an ionosphere can form due to strong ionization of the neutral atmosphere, a cold plasma region may form whose pressure is sufficient to exclude the external nonplanetary plasma.
|
From page 27... ...
Deflection by Planetary Magnetospheres We know little about the solar wind interaction with Mercury except that Mercury has a magnetosphere, bow shock, and transient energetic particle population, suggesting that subetorm-like
|
From page 28... ...
This will be addressed with the Mars Observer in the early l990s. However, we will still be ignorant of all the basic plasma processes on Mars, as well as of the processes In the upper neutral atmosphere.
|
From page 29... ...
Table 3.1 depicts in situ investigations; Table 3.2 depicts remote sensing investigations.
|
From page 30... ...
30 TABLE 3.1 Leveb of In Situ Spacecraft Investigation Disolpline Awaiting Reconnals- Exploration Intensive Physical Recon- sance Study Under naissance . standing Solar physics Sun, solar corona Hellospheric physics Generation of solar wind High-latitude solar wind In-ccliptic solar wind beyond Saturn In-ecilptle solar wind between Bllercury and Jupller Hellopause, Interstellar medium Terrestrial, magnetospheric physics Magnetosphere <60 Rig Earth magnetic tall, wake Terrestrial, atmospheric, ionospheric physics Thermosphere, ionosphere >150 km M exosphere _Solar Probe 1~ Solar Probe - ~0~ ISPM
|
From page 31... ...
31 TABLE S.1 (continued) Disclpllne =on~l~ ~p~-on licensee Phil Recon- sance Study under -~-e amid Panda, _-ed nos~ed~ magn~osphedc phyla Comas Solar wind Oregon of Ears Atmosphere of Bars Soar and l~em~lon of Venus ~agna10sphere of ~ ercu ~ magnetosphere of Junker ~agne10spbere of Saturn ~agne10sphere of ursnus, Neptune upper atmosphere Ionosphere of Judged ~urn, Than Galileo
|
From page 32... ...
32 TABLE 3.2 Levels of Remote Sensing Investigation Discipline Awaiting Preliminary Global Intensive Physical Preliminary Survey Survey Study Under Survey standing Solar physics Coronal holes, large-scale magnetic fields Radio bursts Global oscillation i-fares Internal structure and dynamics solar dynamo Surface plasmamagnetic field interactions Energy storage and release Atmospheric heating Structure and dynamics of corona and solar wind Heliospheric physics Interstellar neutrals Terrestrial, magnetospheric physics Global auroral morphology Remote sensing of magnetospheric structure Terrestrial, atmospheric, ionospheric physics Middle atmosphere SOT/ASO SOT/ASO SOT/ASO 1' ISTP
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.