Mars Gallery Jul 30, 2018 Tags: Mars , Gallery Spiral caps on Mars' North Pole. Each winter in Mars, a new outer layer forms about one meter thick composed of carbon dioxide frozen out of the thin atmosphere. Mars, shown here as the bright yellow light, was captured between the Trifid (Top, small) and Lagoon (Bottom, big) Nebulas. Image by Sebastian Voltmer. Dark Dunes (Namib) on Mars. Similar to wind-created ripples on Earth, but mostly resemble the dunes seen underwater here. (Image Compressed). Gullies "ravines" on Mars. Scientists examined high-resolution compositional data from more than 100 sites throughout Mars. The Curiosity Rover takes first selfie on Mars in 2015. Layered rock formations on Mars. Image taken by Mastcam: Right onboard NASA's Mars rover Curiosity on Sol 1459. First image of Mars' surface during the Viking Project in 1976. Image of Mysterious black streaks on Mars. Astronomers believe they could be dust avalanches, evaporating dry ice sleds, or liquid water flows from the past. Dust storm season on Mars. This image was captured by the Curiosity rover on June 10, 2018. The small solar-powered rover Opportunity stopped operation as the storm grew thicker. White Rock "finger' formations on Mars. What was once thought as just salt deposits, these formations now indicate that it's most likely volcanic ash.