The Hidden World of Light

If there is a mountain in the way of the reflected that red light at night, especial a snow covered mountain, the snow looks red. I took the photo of a particularly good sunset Alpenglow on Utah's Mt Timpanogos (11,977 ft) from our house at 6,000 ft. The sun is setting behind the mountain. Note the dark shadows of the approaching night. That is the basis for Alpenglow-- red or orange or pink tinged clouds at sunset or sunrise reflecting colored sun light near sunset or sunrise. Alpen is German for the Alps, but read it as mountains. The setting sun sometimes turns the clouds red. Clouds reflect sun light, so red clouds reflect red light.

Blue Sky

Sunny Day in Bulgaria

“Red sky at night, sailor's delight”

Same Mountain, Early Morning

Alpenglow is always defined as an event seen when the sun is near the horizon. That is wrong. We once saw Alpenglow produced purple snow at high noon. Mt Timpanogos is part of the 155 mile long Wasatch Range which marks the western edge of the Rocky Mtns. and the start of the Great Basin. We were nearing the southern end of the Wasatch Range at Nephi, UT, on I-15 when we looked up a snow covered canyon in the Wasatch Range. The snow on the mountains creating the canyon was purple. The partially overcast sky was threatening thunder storms-- big dark cloud. With the mountains to our left, and the sun on our right. The purple snow came from sunlight hitting a big dark cloud above which reflected purple light down on the snow. Its all geometry and angles and being in the right place at the right time. These are the kind of things that can happen when you travel if you stay aware.