Related papers: Solar astrometry: the status of art in 2011
The modern methods of measurement of the solar diameter and oblateness are reviewed. Either ground-based or balloon-borne and satellite measurements are considered. The importance of solar astrometry for General Relativity is emphasized,…
Solar radius measurements and their variations -- if any -- are a difficult problem that has vexed researchers for decades. In this paper, we have attempted to clarify the various ways of expressing the definition ''solar diameter'', from a…
The solar diameter changes or not? Whatever will be the answer the methods used for its measurements are more and more challenging, and facing new astrophysical and optical problems since the required space resolution is of astrometric…
The lifetime of a satellite is limited, and its calibration may be not stable, it is necessary to continue ground-based measures of the solar diameter with methods less affected by atmospheric turbulence, and optical aberrations: planetary…
A sunset over the sea surface offers the possibility to chronometrate a solar transit across the horizon. The vertical solar diameter is proportional to the duration of the sunset, the cosine of the azimuth and the cosine of the latitude of…
The study of stellar oscillations - asteroseismology - has revolutionized our understanding of the physical properties of the Sun, and similar potential for other stars has been demonstrated in recent years. In particular, asteroseismic…
X-ray observatories contribute fundamental advances in Solar System studies by probing Sun-object interactions, developing planet and satellite surface composition maps, probing global magnetospheric dynamics, and tracking astrochemical…
The measurement of the Sun's diameter has been first tackled by the Greek astronomers from a geometric point of view. Their estimation of ~1800", although incorrect, was not truly called into question for several centuries. The first…
For many decades the determination of accurate fundamental parameters for stars (masses, radii, temperatures, luminosities, etc.) has mostly been the domain of eclipsing binary systems. That has begun to change as long-baseline…
Asteroid photometry has three major applications: providing clues about asteroid surface physical properties and compositions, facilitating photometric corrections, and helping design and plan ground-based and spacecraft observations. The…
During the last century, with the development of modern physics in such diverse fields as thermodynamics, statistical physics, and nuclear and particle physics, the basic principles of the evolution of stars have been successfully well…
A surprisingly large amount of information on our solar system can be gained from simple measurements of the apparent angular diameters of the sun and the moon. This information includes the average density of the sun, the distance between…
The uncertainty of measurement of solar diameter is depending on the observational time scale. Full-disc images of SDO/HMI and the images from ground observations in Huairou Solar Observing Station have been analyzed to get the values of…
The variation of the solar diameter is the subject of hot debates due to the possible effect on Earth climate and also due to different interpretations of long period solar variabilities, including the total solar irradiance. We shortly…
The size of the diameter of the Sun has been debated for a very long time. First tackled by the Greek astronomers from a geometric point of view, an estimate, although incorrect, has been determined, not truly called into question for…
An inert sphere of a few meters diameter, placed in a special stable geosynchronous orbit in perpetuo, can be used for a variety of scientific experiments. Ground-based observations of such a sphere, "GeoSphere", can resolve very difficult…
The answers to fundamental science questions in astrophysics, ranging from the history of the expansion of the universe to the sizes of nearby stars, hinge on our ability to make precise measurements of diverse astronomical objects. As our…
The measurement of the solar diameter is introduced in the wider framework of solar variability and of the influences of the Sun upon the Earth's climate. Ancient eclipses and planetary transits would permit to extend the knowledge of the…
The Sun has long been considered a constant star, to the extent that its total irradiance was termed the solar constant. It required radiometers in space to detect the small variations in solar irradiance on timescales of the solar rotation…
The new generation of ground-based, large-aperture solar telescopes promises to significantly increase our capabilities to understand the many basic phenomena taking place in the Sun at all atmospheric layers and how they relate to each…