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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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All sourcesNASA NTRSDOE OSTI
NASA NTRS2001

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0266

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Ocuna, M. H.↗
NASA NTRS2001

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0265

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Ocuna, M. H.↗
NASA NTRS2001

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0263

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Ocuna, M. H.↗
NASA NTRS2001

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0262

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Ocuna, M. H.↗
NASA NTRS2001

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0260

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Ocuna, M. H.↗
NASA NTRS2001

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0259

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Ocuna, M. H.↗
NASA NTRS2001

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0258

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Ocuna, M. H.↗
NASA NTRS2001

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0236

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Ocuna, M. H.↗
NASA NTRS2001

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0238

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Ocuna, M. H.↗
NASA NTRS2001

International Solar-Terrestrial Program Key Parameter Visualization Tool Data: USA_NASA_DDF_ISTP_KP_0239

The Global Geospace Science Program (GGS) is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial environment with particular emphasis on "Geospace". The Global Geospace Science Program is the US contribution to the International Solar-Terrestrial Physics (ISTP) Science Initiative. This CD-ROM issue describes the WIND and POLAR spacecraft, the scientific experiments carried onboard, the Theoretical and Ground Based investigations which constitute the US Global Geospace Science Program and the ISTP Data Systems which support the data acquisition and analysis effort. The International Solar-Terrestrial Physics Program (ISTP) Key Parameter Visualization Tool (KPVT), provided on the CD-ROM, was developed at the ISTP Science Planning and Operations Facility (SPOF). The KPVT is a generic software package for visualizing the key parameter data produced from all ISTP missions, interactively and simultaneously. The tool is designed to facilitate correlative displays of ISTP data from multiple spacecraft and instruments, and thus the selection of candidate events and data quality control. The software, written in IDL, includes a graphical/widget user interface, and runs on many platforms, including various UNIX workstations, Alpha/Open VMS, Macintosh (680x0 and PowerPC), and PC/Windows NT, Windows 3.1, and Windows 95.

Ocuna, M. H.↗
NASA NTRS1995

Observations and physical interpretations of the solar wind flow properties as obtained from white light coronagraph aboard SPARTAN 201-01

The solar corona was observed with an externally occulted White Light Coronagraph (WLC) carried on the SPARTAN 201-1 spacecraft on 11-12 Apr. 1993. With observations from WLC and the ground based Mauna Loa White Light Coronagraph, a large number of polar plumes both in the north and south polar holes were traced from 1.16 to 5.5 Rs. Flow properties of the solar wind in coronal holes have been determined (Habbal et al., 1995) by using a two fluid model constrained by density profiles and scale height temperatures from the white light observations, and interplanetary measurements of the flow speed and proton mass flux from Ulysses' south polar passage. Provisions for acceleration by Alfven waves, as well as electron and proton heating, are included in the momentum and the energy equations respectively. The model computations fit remarkably well the empirical constraints of the two different density structures (plumes and coronal holes) for a range of input parameters. In this study we investigate the physical nature of the heating function used in the two-fluid model. Alfven waves have been suggested as the possible source of heating that accelerates the solar wind (Ofman and Davila, 1995). We utilize the density contrast observed in WLC data in the plume and ambient coronal hole region to estimate the Alfven wave frequencies responsible for heating these structures. The source heating function utilized in the two fluid model of the solar wind acceleration will be compared with the resonant Alfven wave heating function.

Guhathakurta, Madhulika↗
NASA NTRS2000

Early Prediction of Geomagnetic Storms and Space Hazards

Solar coronal mass ejections (CMEs) can cause hazadous high-energy particles and geomagnetic storms that, in the more serious instances, can disrupt Earth power grids, communications, and satellites.

space weather space physics solar physics microspa↗
DOE OSTI2024

Generation and Life Cycle of Solar Spicules

The physical mechanism for the creation of solar spicules is proposed with three stages of their life cycle. It is assumed that at stage I the density hump is formed locally in the x-y plane in the lower chromosphere in the presence of temperature gradients of electrons and ions along the z-axis (the vertical direction). In this region, the density structure of quasi-neutral (n i ≃ n e = n) plasma after taking birth is accelerated in the vertical direction owing to the thermal force F th ∝ ∇n(x, y, t) × (∇T e + ∇T i ). The exact time-dependent analytical solution of two-fluid plasma equations is presented assuming that density is maximum at the center of the density structure and decays away from it gradually. The 2D density structure is created as a step function H(t) in time at the bottom of the chromosphere, and consequently, the vertical plasma velocity turns out to be the ramp function of time R(t) = tH(t), whereas the source term S(x, y, t) for the density follows the delta function δ(t) form. The upward acceleration a = a(x, y) $\hat{z}$ produced in this density structure is greater than the downward constant solar acceleration −g ⊙ in the chromosphere. In the transition region, the temperature gradients are steeper; therefore, the upward acceleration increases in magnitude g ⊙ ≪ a and the density hump spends less time there. This is stage II of its life cycle. In stage III, the density structure enters into the corona, where the gradients of temperatures vanish and the structure decelerates to zero velocity under the action of the solar gravitational force.

79 ASTRONOMY AND ASTROPHYSICS↗
NASA NTRS2001

Chaos in the Solar System

The physical basis of chaos in the solar system is now better understood: In all cases investigated so far, chaotic orbits result from overlapping resonances. Perhaps the clearest examples are found in the asteroid belt. Overlapping resonances account for its kirkwood gaps and were used to predict and find evidence for very narrow gaps in the outer belt. Further afield, about one new "short-peroid" comet is discovered each year. They are believed to come from the "Kuiper Belt" (at 40 AU or more) via chaotic orbits produced by mean-motion and secular resonances with Neptune. Finally, the planetary system itself is not immune from chaos. In the inner solar system, overlapping secular resonances have been identified as the possible source of chaos. For example, Mercury in 1012 years, may suffer a close encounter with Venus or plunge into the Sun. In the outer solar system, three-body resonances have been identified as a source of chaos, but on an even longer time scale of 109 times the age of the solar system. On the human time scale, the planets do follow their orbits in a stately procession, and we can predict their trajectories for hundreds of thousands of years. That is because the mavericks, with shorter instability times, have long since been ejected. The solar system is not stable; it is just old!

Lecar, Myron↗
DOE OSTI2013

Solar Neutrinos: Status and Prospects

We describe the current status of solar neutrino measurements and of the theory—both neutrino physics and solar astrophysics—employed in interpreting measurements. Important recent developments include Super-Kamiokande's determination of the ν−e elastic scattering rate for 8 B neutrinos to 3%; the latest Sudbury Neutrino Observatory (SNO) global analysis in which the inclusion of low-energy data from SNO I and II significantly narrowed the range of allowed values for the neutrino mixing angle θ 12 ; Borexino results for both the 7 Be and proton-electron-proton (pep) neutrino fluxes, the first direct measurements constraining the rate of proton-proton (pp) I and pp II burning in the Sun; global reanalyses of solar neutrino data that take into account new reactor results on θ 13 ; a new decadal evaluation of the nuclear physics of the pp chain and CNO cycle defining best values and uncertainties in the nuclear microphysics input to solar models; recognition of an emerging discrepancy between two tests of solar metallicity, helioseismological mappings of the sound speed in the solar interior, and analyses of the metal photoabsorption lines based on our best current description of the Sun's photosphere; a new round of standard solar model calculations optimized to agree either with helioseismology or with the new photospheric analysis; and, motivated by the solar abundance problem, the development of nonstandard, accreting solar models, in order to investigate possible consequences of the metal segregation that occurred in the proto-solar disk. Here, we review this progress and describe how new experiments such as SNO+ could help us further exploit neutrinos as a unique probe of stellar interiors.

helioseismology↗
NASA NTRS1978

A physical mechanism for the prediction of the sunspot number during solar cycle 21

On physical grounds it is suggested that the sun's polar field strength near a solar minimum is closely related to the following cycle's solar activity. Four methods of estimating the sun's polar magnetic field strength near solar minimum are employed to provide an estimate of cycle 21's yearly mean sunspot number at solar maximum of 140 plus or minus 20. This estimate is considered to be a first order attempt to predict the cycle's activity using one parameter of physical importance.

Schatten, K. H.↗
NASA NTRS1994

On the physics of waves in the solar atmosphere: Wave heating and wind acceleration

This paper presents work performed on the generation and physics of acoustic waves in the solar atmosphere. The investigators have incorporated spatial and temporal turbulent energy spectra in a newly corrected version of the Lighthill-Stein theory of acoustic wave generation in order to calculate the acoustic wave energy fluxes generated in the solar convective zone. The investigators have also revised and improved the treatment of the generation of magnetic flux tube waves, which can carry energy along the tubes far away from the region of their origin, and have calculated the tube wave energy fluxes for the sun. They also examine the transfer of the wave energy originated in the solar convective zone to the outer atmospheric layers through computation of wave propagation and dissipation in highly nonhomogeneous solar atmosphere. These waves may efficiently heat the solar atmosphere and the heating will be especially significant in the chromospheric network. It is also shown that the role played by Alfven waves in solar wind acceleration and coronal hole heating is dominant. The second part of the project concerned investigation of wave propagation in highly inhomogeneous stellar atmospheres using an approach based on an analytic tool developed by Musielak, Fontenla, and Moore. In addition, a new technique based on Dirac equations has been developed to investigate coupling between different MHD waves propagating in stratified stellar atmospheres.

Musielak, Z. E.↗
NASA NTRS1993

On the physics of waves in the solar atmosphere: Wave heating and wind acceleration

This paper presents work performed on the generation and physics of acoustic waves in the solar atmosphere. The investigators have incorporated spatial and temporal turbulent energy spectra in a newly corrected version of the Lighthill-Stein theory of acoustic wave generation in order to calculate the acoustic wave energy fluxes generated in the solar convective zone. The investigators have also revised and improved the treatment of the generation of magnetic flux tube waves, which can carry energy along the tubes far away from the region of their origin, and have calculated the tube energy fluxes for the sun. They also examine the transfer of the wave energy originated in the solar convective zone to the outer atmospheric layers through computation of wave propagation and dissipation in highly nonhomogeneous solar atmosphere. These waves may efficiently heat the solar atmosphere and the heating will be especially significant in the chromospheric network. It is also shown that the role played by Alfven waves in solar wind acceleration and coronal hole heating is dominant. The second part of the project concerned investigation of wave propagation in highly inhomogeneous stellar atmospheres using an approach based on an analytic tool developed by Musielak, Fontenla, and Moore. In addition, a new technique based on Dirac equations has been developed to investigate coupling between different MHD waves propagating in stratified stellar atmospheres.

Musielak, Z. E.↗