spacetoday.net: Venus atmosphere once more like Earth

Posted: Fri, Nov 30, 2007, 6:40 AM ET (1140 GMT)
Venus Express illustration (ESA)

The atmosphere of the planet Venus early in its history was once more like Earth's, with similar amounts of water, but was changed by its proximity to the Sun, scientists announced this week. In a group of papers published in the journal Nature, scientists reported on the latest findings from ESA's Venus Express mission. Among those findings was a high ratio of deuterium in the planet's atmosphere, confirming a finding from a NASA mission nearly 30 years ago. That level of deuterium suggests that the planet once had a significant amount of water in the atmosphere that was broken down into hydrogen and oxygen by solar radiation, with most of the hydrogen escaping to space. Venus Express also confirmed that there is lightning in the planet's atmosphere, occurring more frequently than on Earth.