Since the late 1950s, increasingly clear evidence from various space probes showed Venus has an extreme climate, with a greenhouse effect generating a constant temperature of about 500 °C on the surface. The atmosphere contains sulfuric acid clouds and the atmospheric pressure at the surface is 90 bar, almost 100 times that of Earth and similar to that of more than 1,000 m (3,300 ft) deep in Earth's oceans. In such environment, and given the increasingly hostile characteristics of the Venusian weather, the chances of life as we know it are excluded from the surface of Venus.