Giovanni Cassini

The specter of the crown very shows shining lines that, up to 1940, were not known. Currently and it knows that they are produced by atoms of iron, nickel, neon and calcium highly ionized and not for no strange element, as previously she was thought. The fact of some times ionized in the crown to exist these elements imply that its temperature must be much high, therefore are necessary much energy to extract many electrons of an atom. The crown must have around 1 million of degrees Kelvin. Of the crown it emanates the solar wind, particle a continuous flow emitted of the crown that causes a loss of the mass on the part of the Sun. The Solar wind that reaches the Land is of approximately 7 prtons/cm travelling about 400 km/s, that it is captured by the magnetic field of the Land, forming the cinturo of Van Allen, in the terrestrial magnetosphere. The diameter of the Sun is around 1.390.000 km and its surface arrives 6000 K, in the center reaches 20 million degrees K.

The term Sun is of origin Greek? helium? discovered first in the Sun and one room century was discovered in the Land. The helium if establishes in the Sun to a temperature equivalent 14.000.000 C, emitting violent rays X, if these rays penetrated in the terrestrial atmosphere would cause bad a harmful one to the life of the man. In the distance of the Sun it was discovered in 1673, for Jean Richer (1630-1696) and Giovanni Cassini (1625-1712) that they had determined in the distance of Mars and with this they had esteem the astronomical unit as 140 million km (150 km is the current value), was possible to determine its luminosity, that is the power that it produces. The luminosity of the Sun currently determines in 3,9×10 watts = 3,9×10 ergs/s.