NASA released a picture in April 2021 depicting dunes colored bright blue surrounded by the red surface of Mars.
The picture didn't show actual colors on Mars — the colors represented variance in temperature on the surface.
On April 8, 2021, NASA released a photograph that appeared to show bright, cerulean blue dunes surrounded by the red surface of Mars. The picture can be seen in the tweet posted by Space.com, a space and astronomy news website:
The picture is beautiful, but it doesn't show the actual colors on the surface of the Red Planet. NASA pointed out that the picture is a "false color image" that depicts temperature, not color.
"In this false-color image, areas with cooler temperatures are recorded in bluer tints, while warmer features are depicted in yellows and oranges. Thus, the dark, sun-warmed dunes glow with a golden color," per NASA.
Per Space.com, the picture was presented as part of a series marking the 20th anniversary of the Odyssey, the "longest-working Mars exploration craft in history." The picture is a "combination of images taken between December 2002 and November 2004 by the Thermal Emission Imaging System instrument on the Mars Odyssey orbiter."