Did the Perseverance rover capture a rainbow on Mars? This image, from the rover’s left rear Hazard Camera, sure looks like it. But alas, no. However, film director JJ Abrams would be proud.
The rover’s official Twitter account explained it best, that rainbows just aren’t possible on Mars, and this is simply a lens flare:
“Rainbows aren’t possible here. Rainbows are created by light reflected off of round water droplets, but there isn’t enough water here to condense, and it’s too cold for liquid water in the atmosphere. This arc is a lens flare.”
A lens flare is created when non-image forming bright light (such as direct sunlight) enters the lens and subsequently hits the camera’s digital sensor and scatters. Here’s another lens flare image, which also shows the recently dropped off Ingenuity helicopter:
Atmospheric science aside, these are extremely beautiful pictures from Mars. If you’re wondering why you perhaps haven’t seen lens flares like this before from the Red Planet, there probably have been, but the quality of Perseverance’s cameras are showing so much more crisp detail in its images.
Here’s another cool lens flare image, a close-up of one of Perseverance’s wheels, also taken by one of the rear Hazcams:
Image Credit: NASA/JPL-Caltech
The previous Mars Exploration Rovers had and the Opportunity rover has solar filters on most of their cameras. In addition to solar filters, Perseverance also has sunshades on the front Hazcams. This was considered mission-critical, because it needs them for driving forward (Perseverance is usually driving forward). Sunshades weren’t considered essential on the rear Hazcams, so some of those images have scattered light artifacts, such as the one below:
The lead lens flare image was taken on Sol 43 (that’s April 4, 2021 for us Earthlings).
Perseverance continues to take incredible images from ALL its cameras. See all of the raw images here.