Results 221 to 230 of about 247,122 (268)
Some of the next articles are maybe not open access.
Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 2002
In this article I review the fundamentals of solar-dynamo theory. I describe both historical and contemporary observations of the solar magnetic field before outlining why it is believed that the solar field is maintained by a hydromagnetic dynamo. Having explained the basic dynamo process and applications of the theory to the Sun, I shall conclude by ...
openaire +2 more sources
In this article I review the fundamentals of solar-dynamo theory. I describe both historical and contemporary observations of the solar magnetic field before outlining why it is believed that the solar field is maintained by a hydromagnetic dynamo. Having explained the basic dynamo process and applications of the theory to the Sun, I shall conclude by ...
openaire +2 more sources
The New Solar Composition and the Solar Metallicity
2010We review the current status of our knowledge of the chemical composition of the sun and present a redetermination of the solar abundances of all available elements. These new results have very recently been published by Asplund et al. (2009). The basic ingredients of this work, the main results and their implications are discussed.
Grevesse, Nicolas +3 more
openaire +3 more sources
Solar and solar-wind isotopic compositions
Earth and Planetary Science Letters, 2004With only a few exceptions, the solar photosphere is thought to have retained the mean isotopic composition of the original solar nebula, so that, with some corrections, the photosphere provides a baseline for comparison of all other planetary materials. There are two sources of information on the photospheric isotopic composition: optical observations,
Wiens, Roger C. +3 more
openaire +2 more sources
Turbulence in the Solar Atmosphere and Solar Wind
Space Science Reviews, 2010The objective of this review article is to critically analyze turbulence and its role in the solar atmosphere and solar wind, as well as to provide a tutorial overview of topics worth clarification. Although turbulence is a ubiquitous phenomenon in the sun and its heliosphere, many open questions exist concerning the physical mechanisms of turbulence ...
Petrosyan, A. +8 more
openaire +3 more sources
The solar wind: from solar minimum to solar maximum
Advances in Space Research, 2001We describe the evolution of the heliosphere from solar minimum to solar maximum from a solar wind perspective. With the current fleet of spacecraft progress can be made in separating radial distance, heliolatitude, and solar cycle effects. The solar wind speed decreases with distance, but the changes from solar minimum to solar maximum produce a ...
John D. Richardson +2 more
openaire +1 more source
Solar Fuels and Solar Chemicals Industry
Accounts of Chemical Research, 2017Two decades of solar energy research, since the "Holy Grails" Account on Artificial Photosynthesis, has delivered astounding discovery that sets the stage for a paradigm shift from a fuels and chemicals industry powered by fossil fuels to one powered by the sun.
openaire +2 more sources
Solar radiation and solar activity
Quarterly Journal of the Royal Meteorological Society, 1970AbstractUsing high‐altitude balloon soundings (1961 to 1968) and other data, it is shown that the most reliable maximum value of the solar constant is at present 1.94 cal cm−2 min−1, to an accuracy of 1 per cent. This value is observed with Wolf numbers between 80 and 100, below or above which the solar constant decreases. The maximum decrease does not
K. Ya. Kondratyev, G. A. Nikolsky
openaire +1 more source
Solar neutrinos and nuclear reactions in the solar interior
2018We discuss the results of Homestake and Kamioka experiments, showing that - if the results of these experiments are taken at their face values - one way to save "conventional neutrinos" is to look for a nuclear solution decreasing both 7Be and 8B neutrino fluxes with respect to the predictions of the standard solar models.
Castellani V +2 more
openaire +4 more sources
Hybrids of solar sail, solar electric, and solar thermal propulsion for solar-system exploration
2012 IEEE Aerospace Conference, 2012Solar sails have long been known to be an attractive method of propulsion in the inner solar system if the areal density of the overall spacecraft (S/C) could be reduced to ∼10 g/m2. It has also long been recognized that the figure (precise shape) of useful solar sails needs to be reasonably good, so that the reflected light goes mostly in the desired ...
openaire +1 more source