Observed at night through a telescope, Venus shines a slightly yellowish white. This is actually due to its thick cloud cover, which reflects the Sun's light and conceals the surface, explaining why Venus has long been a mystery.
Venus was the first planet to be visited by spacecraft, with the launch of the Mariner 2 probe in 1962. Between then and 1989, some 20 probes—including Mariner, Pioneer Venus, Venera and Vega—passed, orbited and even landed on the surface of Venus.
The Soviets made about 10 successful landings, gathering data and analysing samples. In June 1985, a pair of balloons released by space probes Vega 1 and 2 drifted for 2 days through Venus’ atmosphere, taking numerous measurements.
In 1989, the US probe Magellan took images of more than 90% of the planet’s surface, while its altimetry radar provided us with a series of relief maps.
In 2006, the European probe Venus Express will make a detailed analysis of Venus’ atmosphere.
Venus Fact Sheet, National Space Science Data Center (NASA)
VENUS EXPRESS mission, ESA website
Solar System exploration, NASA website
Planetary photojournal - NASA website
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