Desafio: qual será a descoberta feita pelo rover Curiosity em Marte?

talvez algum mineral resultante da precipitação de soluto de uma solução saturada, tipo halite (sal gema)

Placas tectônicas se movendo. Mistério resolvido.

água na fases sólida, liquida e gasosa já foi descoberta em Marte. Hoje, no presente, líquida.

Em grandes quantidades sólida nas calotas e sob a superfície em latitudes mais equatoriais, gasosa em pequenas quantidades na atmosfera e líquida em gotas quando o gelo não sublima instantaneamente.

No passado há um conjunto enorme de evidências de ter existido na fase líquida, com rios, correntes e bacias oceânicas.

“An artist’s impression of what ancient Mars may have looked like, based on geological data
Water on Mars exists almost exclusively as water ice. The Martian polar ice caps consist primarily of water ice, and further ice is contained in Martian surface rocks at more temperate latitudes (permafrost). A small amount of water vapor is present in the atmosphere.[1] There are no bodies of liquid water on the Martian surface.
Current conditions on the planet surface do not support the long-term existence of liquid water. The average atmospheric pressure and temperature are far too low, leading to immediate freezing and resulting sublimation. Despite this, research suggests that in the past there was liquid water flowing on the surface,[2][3] creating large areas similar to Earth’s oceans.[4][5][6][7]
There are a number[8] of direct and indirect proofs of water’s presence either on or under the surface, e.g. stream beds,[9][10][11] polar caps, spectroscopic measurement,[12] eroded craters or minerals directly connected to the existence of liquid water (such as goethite), grey, crystalline hematite, phyllosilicates, opal,[13] and sulfate.[14][15] With the improved cameras on advanced Mars orbiters such as Viking, Mars Odyssey, Mars Global Surveyor, Mars Express, and the Mars Reconnaissance Orbiter pictures of ancient lakes,[16][17][18][19][20][20][21][22] ancient river valleys,[9][23] and widespread glaciation[24][25][26][27][28] have accumulated. Besides the visual confirmation of water from a huge collection of images, an orbiting Gamma Ray Spectrometer found ice just under the surface of much of the planet.[29][30] Also, radar studies discovered pure ice in formations that were thought to be glaciers.[31][32][33][34][35][36] The Phoenix lander exposed ice as it landed, watched chunks of ice disappear,[37][38][39] detected snow falling,[40] and even saw drops of liquid water.[41][42][43]