"There is a large crater in the western portion of the landing zone which contains rougher terrain than what we've seen elsewhere, " Zurek told reporters.

BBC: Mars probe canyon crash theory

Richard Zurek, MPL project scientist, described the Denver Post exclusive as "premature", and said the crater theory was just one of several scenarios still being investigated.

BBC: Mars probe canyon crash theory

"Before, we could hardly make out dunes there, " said Rich Zurek, project scientist for the Mars Climate Orbiter and Mars Polar Lander, set to arrive at the planet in September and December, respectively.

CNN: Scientists debate implications of Mars pictures

"Now with the new images, we're able to watch when the frost comes and goes and we can see that dunes are moving today and aren't just relics from times past, " Zurek said.

CNN: Scientists debate implications of Mars pictures