| Venus is the brightest object in our sky, after the sun and moon. Swirling clouds of sulfur and sulfuric acid obscure Venus’s surface and inhibited study of the planet from Earth until technology permitted space vehicles, outfitted with probes, to visit it. These probes determined that Venus is the hottest of the planets, with a surface temperature of about 460° C (about 860° F). Scientists believe that a greenhouse effect causes the extreme temperature, hypothesizing that the planet’s thick clouds and dense atmosphere trap energy from the sun. |