Figure 11-11 The Pleiades and Its H-R Diagram (a) The Pleiades star cluster is 117 pc (380 ly) from Earth in the constellation Taurus and can be seen with the naked eye. (b) Each dot plotted on this H-R diagram represents a star in the Pleiades whose luminosity and surface temperature have been measured.

(Note: The scales on this H-R diagram are different from those in Figure 11-12b.) The Pleiades is about 100 million (10 × 10⁸) years old. (NASA, ESA and AURA/Caltech)