What are my eyes seeing? What are those strange blue spots that glow in Earth’s atmosphere?
We owe this image to an astronaut aboard the International Space Station (ISS), who took a peculiar image of Earth from space with these curious blue spots of light that shine brightly. It is nothing from another world, but a coincidence of two natural phenomena that were captured at the same time in photography.
The first, a lightning strike somewhere in the Gulf of Thailand ; that as there was a gap in the top of the clouds, the rays illuminated the surrounding walls of the circular structure, creating a striking ring of light; the second, at the top right of the image, is nothing but distorted light from the Moon, looking like a bright blue patch with a fuzzy halo.
Why do we see this blue effect?
As NASA explains, the different colors of visible light have different wavelengths, which affects their interaction with atmospheric particles . Blue light has the shortest wavelength and therefore the one most likely to be scattered, hence we saw the bluish moon. It is the same explanation why we see blue sky during the day, the blue wavelengths of sunlight are scattered more and become more visible to the human eye.
The photo was posted online on October 9 by NASA’s Earth Observatory ( NASA EARTH OBSERVATORY ).
Reference: NASA EARTH OBSERVATORY / ISS