howe is it measured?
In SI units, luminosity is measured in joules per second, or watts and in astronomy, in the terms of the luminosity of the Sun, L
Luminosity
In SI units, luminosity is measured in joules per second, or watts. In astronomy, values for luminosity are often given in the terms of the luminosity of the Sun, L.
characteristics of stars based on the characteristics of the sun A star with mass greater than 0.4 times the Sun's will expand to become a red giant when the hydrogen fuel in its core is exhausted. have these been observed since ancient times? UNANSWERABLE how are they measured? It is often most convenient to express mass, luminosity, and radii in solar units could you please explain the second term? It is an absolute measure of radiated electromagnetic power, the radiant power emitted by a light-emitting object.
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Luminosity [SEP] Introduction
Luminosity is an absolute measure of radiated electromagnetic power (light), the radiant power emitted by a light-emitting object. In astronomy, luminosity is the total amount of electromagnetic energy emitted per unit of time by a star, galaxy, or other astronomical object. In SI units, luminosity is measured in joules per second, or watts. In astronomy, values for luminosity are often given in the terms of the luminosity of the Sun, L. Luminosity can also be given in terms of the astronomical magnitude system: the absolute bolometric magnitude (M) of an object is a logarithmic measure of its total energy emission rate, while absolute magnitude is a logarithmic measure of the luminosity within some specific wavelength range or filter band.