The shimmering turquoise surface of Bear Lake is something most residents in the region are familiar with, but it’s doubtful many have seen the lake quite like it appears in an image from space released this week by NASA.
According to the space agency, the 19-mile-long lake straddling the Utah-Idaho border “caught the eye” of an astronaut on the International Space Station on Sept. 6, and one of the photos taken by the astronaut was featured Dec. 11 as the Image of the Day on the NASA website.
In addition to the bright color of the water, what really stands out in the photo are two large white spirals in the middle of the lake that NASA described as “sediment swirls.” Smaller, less conspicuous spirals are also visible on the north end of the lake.
“The two swirls near the center are rotating in the deepest water — perhaps from outflow from Swan Creek or Fish Haven Creek,” NASA said in a short narrative accompanying the photo. “The more diffuse swirls at the north end of the lake (lower right) likely formed from sediment entering from North Eden Creek. This sediment is carried north along the shoreline by lake currents, joining with sediment eroded from the white beaches.”
The website entry also makes note of a small delta containing two circular irrigated fields on the east side of the lake, calling it “one of the few flat places in this mountainous landscape.”
The image was produced using a Nikon D4 digital camera with a 600 millimeter lens — equipment beyond the capabilities of most amateur photographers. The sediment swirls are not visible in the satellite image of Bear Lake on Google Maps.
Had NASA wanted to provide its worldwide internet audience with more information, it could have also explained the turquoise color of Bear Lake, which scientists have attributed to the sun’s reflection off calcium carbonate (limestone) deposits suspended in the lake’s uncommonly clear water.
The color has earned Bear Lake the nickname “The Caribbean of the Rockies.”
