Once in a Blue Dune! NASA captured images of a 'blue' sand dune on Mars and the photos are mind-blowing.

Blue sand dune mars
NASA photographed an exquisite sand dune on Mars over the summer that's out of this world. The dune appears blue in an enhanced-colour image taken by the Mars Reconnaissance Orbiter (MRO), though it's actually a greyish hue. The visual effect comes from upping the contrast, a trick that allows researchers to see more detail in images of Mars.
Sand dunes often accumulate in the floors of craters. In this region of Lyot Crater, NASA's Mars Reconnaissance Orbiter (MRO) shows a field of classic barchan dunes on Jan 2018. Just to the south of the group of barchan dunes is one large dune with a more complex structure. This particular dune, appearing like turquoise blue in enhanced colour.T he dune is located in the red planet's Lyot Crater, a large crater on Mars that is known for its patterned ground."It is made of finer material and/or has a different composition than the surrounding [dunes]," NASA said...The MRO originally captured the image in January 2018.