- The Hertzsprung–Russell diagram (abbreviated as H–R diagram, HR diagram or HRD) is a scatter plot of stars showing the relationship between the stars’ absolute magnitudes or luminosities and their stellar classifications or effective temperatures. The diagram was created independently in 1911 by Ejnar Hertzsprung and by Henry Norris Russell in 1913, and represented a major step towards an understanding of stellar evolution.
Oh, Andy loved geology. I imagine it appealed to his meticulous nature. An ice age here, million years of mountain building there. Geology is the study of pressure and time. That’s all it takes, really. Pressure, and time. That and a big damn poster. Like I said, in prison, a man will do almost anything to keep his mind occupied. Turns out Andy’s favorite hobby was totin’ his wall out into the exercise yard, a handful at a time. I guess after Tommy was killed, Andy decided he’d been here just about long enough.
Ellis Boyd, The Shawshank Redemption
