Colonization of Venus
Venus's atmosphere is made mostly out of carbon dioxide, which, after filtering from sulfuric acid, can be used to grow food. Because nitrogen and oxygen are lighter than the carbon-dioxide that makes the atmosphere, breathable-air-filled balloons will float at a height of about . At this height, the temperature is a manageable ; or if we could get higher (see ).
Atmosphere of Venus
In 2009 a prominent bright spot in the atmosphere was noted by an amateur astronomer and photographed by "Venus Express". Its cause is currently unknown, with surface volcanism advanced as a possible explanation.