These observations have essentially confirmed three things. One, that carbon dioxide ice particles observed in these polar clouds are large enough to fall to the surface. Second, that these "flakes" of carbon dioxide ice could develop and fall to the ground during the lifespan of the clouds. And most importantly, the MRO has provided strong evidence that they do exactly that. By pointing the orbiter's instruments at the horizon from an angle rather than straight down at the ground from above, they were able to observe the presence of these ice particles extending from the clouds to the surface.