Colorful sparkles in freshly fallen snow – Bob King / News Tribune
I was so surprised to wake up to four inches of snow with plenty still falling this Easter Sunday. A random survey of a minute’s worth of snowflakes on my dark-colored jacket revealed a variety of attractive six-sided and six-pointed shapes.
Ice is a hexagonal crystal and can act like a prism in the right circumstances to spread or refract light into a rainbow of colors. Snow crystals do this too.
When the sun comes out later today, try to see these colors for yourself by looking at the newly-fallen snow from 10 or 20 feet away while facing in the sun’s direction. Hunker down to get a low angle and peer into the glinting snow cover. It might take a few seconds, but you should start to see tiny glints of red, blue, green and yellow.
Once seen, you’ll be amazed at how vivid the hues are. Try moving your head slowly from left to right and watch what happens to the colors.
Astronomers use specialized prisms to spread starlight into a rainbow. Tucked between the colors are dark lines like fingerprints that reveal the elements stars are made of. More on this in a future blog. In the meantime, I hope refraction puts a sparkle in your day.
Tonight we have about an hour of darkness before moonrise (10 p.m. for the Duluth area). This would be a good time to follow the Dipper’s Handle to Arcturus and from there to Bootes. As always, if you’d like to share an observation, just add a comment and I’ll find a place for it. Happy star hunting.