Colder temperatures have brought something a little extra dazzling to the night sky for residents across the northern U.S. Hundreds have witnessed a phenomenon known as “light pillars,” which are vertical shafts of light appearing as beams that shoot up into the night sky, according to CNN.
“It was almost like I was looking at the northern lights because they were bouncing, moving and changing in appearance,” National Weather Service Meteorologist Bill Taylor said of the anomaly, which he photographed in North Platte, Nebraska, earlier in the week.
The pillars are the result of ice crystals near the ground that reflect light. When conditions are right, the small particles are just light enough to float, stacking on top of each other as they slowly move through the atmosphere. They become like a mirror in that they reflect any nearby light sources, such as street lamps and the moonlight. Temperatures need to be extremely cold and the air needs to be calm for the phenomenon to occur.
“The higher the crystals in the atmosphere, the taller the pillar,” the National Weather Service in La Crosse, Wisconsin, told CNN.
The brilliant beams are something of an optical illusion, however. While they look like they are shooting up into the air, something else is happening. The light source that is moving through space is actually redirected to the eye as the ice particles align vertically.
Sightings of the dazzling formations have been reported in Michigan, and CNN wrote that as temperatures in northern Minnesota, North Dakota and Montana struggle to reach above zero degrees this week, the chances are good that many in those areas will be able to witness the unusual events — as long as they are willing to brave the frigid air.
The temperature had dropped to minus 20 Fahrenheit the night Taylor captured the rarity on film in Nebraska, according to NWS Meteorologist Darren Snively.
Last month, a similar occurrence happened with the full moon. Ice crystals in the atmosphere reflecting light off of thin clouds formed what looked like a halo around the satellite, as shown here. The halos can appear to be different colors and even resemble a rainbow due to their refraction, reflection, and dispersion, according to WMC-TV in Memphis, Tennessee.