Turn off the daylight and horizon displays. Use the “Selection”
button and click on “Find.” In the window, type in
Pleiades and then click “Find.” Zoom in on the Pleiades
until the field of view is about 3°. Click on “H-R” button
on the vertical toolbar to display the H-R diagram of the
cluster. Use the Selection Tool to point at various stars in
the Pleaides. The red dot on the H-R diagram display
shows the position of the star at which you are pointing.
Keep looking until you find the hottest main sequence star
in the cluster. Double click to find the luminosity and
temperature of the hottest star. Using Table 19.1 and
Equation 19.5, estimate the age of the Pleiades from the
properties of the hottest main sequence star in the cluster.