On 9 November 2005, 10 years ago today, ESA’s Venus Express spacecraft left Earth and began its 153-day journey to Venus. The craft then spent eight years studying the planet in detail before the mission came to an end in December 2014.
One of the mission aims was to observe the planet’s atmosphere continuously over long periods in a bid to understand its dynamic behaviour.
The atmosphere is the densest of all the terrestrial planets, and is composed almost entirely of carbon dioxide. The planet is also wrapped in a thick layer of cloud made mostly of sulphuric acid. This combination of greenhouse gas and perennial cloud layer led to an enormous greenhouse warming, leaving Venus’ surface extremely hot – just over 450ºC – and hidden from our eyes.
Although winds on the planet’s surface move very slowly, at a few kilometres per hour, the atmospheric density at this altitude is so great that they exert greater force than much faster winds would on Earth. … (ESA)