Atmosphere of Uranus vast. The number density of atomic hydrogen in the corona falls slowly with the distance from the planet, remaining as high a few hundred atoms per cm at a few radii from Uranus. The effects of this bloated exosphere include a drag on small particles orbiting Uranus, causing a general depletion of dust in the Uranian rings. The infalling dust in turn contaminates the upper atmosphere of the planet. Uranus has a relatively bland appearance, lacking broad colorful bands and large clouds prevalent on Jupiter and Saturn. No discrete features were observed in Uranus's atmosphere before 1986. The most conspicuous
Atmosphere of Mars and southern hemispheres. Mars's temperature difference greatly influences the amount of water vapor in the atmosphere, because warmer air can contain more moisture. This, in turn, affects the production of ozone-destroying hydrogen radicals. In early 2016, Stratospheric Observatory for Infrared Astronomy (SOFIA) detected atomic oxygen in the atmosphere of Mars. This was the first time in forty years it was detected, the last time being the Viking and Mariner missions in the 1970s. Molecular nitrogen (N) is present in the atmosphere at 1.9%. Measurements by various robotic missions, and analyses of Martian meteorites, show that the atmosphere is enriched in