Alpenglow is a term often used to describe the last light falling on many of the natural landmarks seen in Yosemite Valley.
After the sun sets, and the light fades, a phenomenon takes place, in what many photographers call the "magic hour".
The granite monoliths of El Capitan, and Half Dome intensify their color, and seem to actually give off their own colorful light. Imagine hundreds of years ago when explorers first entered these glorious places.
The experience must have transformed them.