The desolate land that covers our neighbouring planet, giving it its unmistakeable red hue, has continued to surprise researchers since they began investigating Mars' surface. Now the red planet has revealed another surprise, which could provide scientist with clues into the history of the world. Researchers have discovered a new type of dune on Mars that look similar to those that form underwater on Earth. Researchers have discovered a new type of dune on Mars, and it is unlike anything seen on Earth. These ripples are different in terms of size, morphology, and the way they form, from any other known.