Sphere celestial

The physical quantity directly detected by the interferometer is the correlated flux and the complex visibility for a given wavelength, corresponding to an angle frequency on the celestial sphere which depends on the projected baseline. Let us summarise which kind of quantities an interferometer can deliver and which kind of information on the observed source can be extracted. 

H.W. Kroto, Buckminsterfullerene, a celestial sphere that fell to Earth. Angew. Chem. Int. Ed, 31 (1992) 111. 

On the road that leads from appearance to essence, the astronomer s first care is to allow for the effects of distance. To this end all stars are artificially located at the same distance in order to compare their brightnesses in a completely objective way. Curiously, this ploy restores the old idea of a celestial sphere, a purely mental construct so long discredited, dedicating it to the cause of objective knowledge. 

Tis clear they shonld halt on the grave of old Dalton On their way to celestial spheres ... 

The celestial sphere is a fixed sphere of infinite radius, concentric with the center of the earth. The celestial North and South poles (Pjv and P ) are an extension of the earth s North and South poles to infinity. The celestial equator is the great circle whose poles are Pn and Ps. The (local) zenith point Z is the point vertically above an observer at some arbitrary point on the earth s... 

The celestial sphere, with local zenith Z, and a point B (a star). Note the spherical triangle BZPN. 

Kroto, H. Nanotechnology 1992, i, 111. A lecture given in the same title is also available as an audio hie from http //www.learnoutloud.eom/Catalog/Science/Scientists/C60-The-Celestial-Sphere-That-Fell-to-Earth/15201... 

BERTHELOT 1885 records a sigil from the Greek astrological tradition. Intended to refer to the celestial spheres in general ... 

The nature of the philosopher s stone depends on the positive interaction (+) of Sun, Moon and Hermes Trismegistos, the mythical founder of alchemy, whose name appears on the Rosetta stone and who represents the syncretic link between the Greek god Hermes and the Egyptian moon god Thot. Active masculine qualities are separated from passive feminine qualities. The relationship between Avicenna s two-element model and the four elements of Aristotle is shown. The total pattern resembles the incommensurable nesting of Platonic solids within the celestial sphere. 

The sidelobes shown in figure 1 appears as equidistant circles only because we plot the correlation map on a plane perpendicular to the RMC spin axis. When projected on the celestial sphere the sidelobes are neither circular nor equidistant. This means, that if we overlay the correlation maps for many observations, with different orientations of the spin aods, then only the central peaks will add constructively from all exposures, while the sidelobes wiU have differing phases, and therefore diminish in relative importajice in the combined image. This is illustrated in figure 2. 

H.W. Kroto (1992) Angewandte Chemie International Edition, vol. 31, p. Ill - Cgo Buckminsterfullerene, the celestial sphere that fell to earth . 

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