Obscuring of one celestial body by another, either by direct superposition or by the casting of a shadow. Solar eclipses are of three kinds, total (when the Moon completely eclipses the Our parent star. The structure of Sun's interior is the result of the hydrostatic equilibrium between gravity and the pressure of the gas. The interior consists of three shells: the core, radiative region, and convective region. Image source: http://eclipse99.nasa.gov/pages/SunActiv.html. The core is the hot, dense central region in which the), annular (when a complete ring of sunlight escapes around the edge of the Sun), and partial. Lunar eclipses are of two types, total and partial.
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