A simple version of an H R diagram shows only the main sequence, masses and lifetimes.Long Description: Traveling along the main sequence from upper left to lower right, or from high surface temperature and high luminosity to low surface temperature and low luminosity, we encounter masses relative to the sun and lifetimes in order within the following table. Type, Surface temperature, Luminosity in solar units, Stellar Mass, Stellar LifetimeO, over 40000 Kelvin, almost 10 to the sixth power solar units, 60 M sub Sun, Less than Lifetime 10 to the seventh power yearsO, about 40000 Kelvin , between 10 to the fifth and 10 to the sixth power solar units, 30 M sub Sun, Less than Lifetime 10 to the seventh power yearsO, about 30000 Kelvin, between 10 to the fourth and 10 to the fifth power solar units, Between 30 and 10 M sub sun, Lifetime 10 to the seventh power yearsBetween O and B, about 28000 Kelvin, 10 to the fourth power solar units, 10 M sub Sun, Lifetime of between 10 to the seventh power and 10 to the eighth power yearsB, about 15000 Kelvin, between 10 to the second and 10 to the third power