The table below lists stars of several different sizes. Information…

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Question Answered step-by-step The table below lists stars of several different sizes. Information… The table below lists stars of several different sizes.  Information about spectral type, luminosity class, mass, and luminosity is also given.The Sun’s main sequence lifetime is approximately 10 billion years.  This calculation comes from the following:  (1) the amount of energy released by proton-proton chain reactions, (2) the amount of mass the Sun has available to use for nuclear fusion in its core (something like 10-13% of its total mass), and the rate at which the Sun is putting out energy (its luminosity).  Based on measurements of radioactive elements in the Solar System, astronomers believe the Sun is already about 5 billion years old, meaning it is halfway through its lifetime.  Furthermore, we can estimate the lifetimes of other stars using similar reasoning simply by scaling the result for the Sun.  More mass = a longer lifetime (more fuel to burn), while a greater luminosity = a shorter lifetime (more energy output because fuel is being used up faster).  This leads to the following equation: In this equation,  is the star’s lifetime, M is the star’s mass in solar units (so M = 1 for the Sun, a star with double the mass would have M = 2), and L is the star’s luminosity in solar units (same idea as for mass).  Obviously, if you put in 1 for both M and L, you get 10 billion years, which is the Sun’s estimated main sequence lifetime.Image transcription textMAIN MASS LUMINOSITY — SPECTRAL LUMINOSITY SAQUENCE STARS (RELATIVE [RELATIVE TYPECLASS LIFETIME (m TO THE SUN)_ TO THE SUN)_ YEARS) Alpha , 62 V 1.1 1.52 Centauri A Eta Centauri 31.5V 12 8700 11 Leonis , , GS V 0.96 0.76 Minoris Barnard’s Star M4 V 0.144 0.0035 Antares M0.5 | 12… Show more… Show more  Science Astronomy PHYS 210 Share QuestionEmailCopy link Comments (0)