NASA releases spectacular photo of 'rainbow' on Mars

A recent image taken by NASA’s Perseverance rover appears to show a breathtaking rainbow on Mars. The photograph has caused mass speculation online, as scientific evidence shows there shouldn’t be rainbows on Mars. On Earth, rainbows appear when sunlight meets the right atmospheric conditions, in which the light hits and reflects off of individual water droplets in the atmosphere. However, given the cold, thin, and dry atmosphere of Mars, the chances of the image being of an actual rainbow are unlikely.

... users have speculated that it could be a “dustbow,” with the reflections being caused by dust rather than water droplets. Further speculation on the site has come from a 2015 “Ask Me Anything” with NASA team members in which NASA Mars Program Office Chief Scientist Rich Zurek said it was possible that “icebows” could appear on Mars, because while there are no water droplets, snow has been observed at the Poles.

However, the most supported theory appears to be that the “rainbow” was caused by an artifact causing random rays of light entering and randomly dispersing inside the lens, similar to a “lens flare” in your typical camera. This was supported by Dave Lavery, the program executive for Solar System Exploration at NASA, who told Forbes, “Definitely not a rainbow. … It is just internal reflections in the camera lens."

https://thehill.com/changing-america/resilience/smart-cities/546655-nasa-releases-spectacular-photo-of-rainbow-on-mars