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 Venus Earth, the upper atmosphere has been proposed as a location for both exploration and colonization. On January 29, 2013, ESA scientists reported that the ionosphere of the planet Venus streams outwards in a manner similar to "the ion tail seen streaming from a comet under similar conditions." Mikhail Lomonosov was the first person to hypothesize the existence of an atmosphere on Venus based on his observation of the transit of Venus of 1761 in a small observatory near his house in Saint Petersburg, Russia. The atmosphere of Venus is composed of 96.5% carbon dioxide, 3.5% nitrogen, and traces of other