The European Space Agency (ESA) launched its maiden mission to Venus early on Wednesday.
The "Venus Express" took off from the Baikonur space centre in Kazakhstan at 03.33 GMT following a two-week delay caused by technical problems on the Russian Soyuz carrier rocket.
After travelling through space for 162 days the probe will go into Venusian orbit in April 2006 and gather information about the planet, which has an average surface temperature of a staggering 470 degrees Celsius.
The probe will spend almost 500 days moving in an elliptical orbit over the poles, passing at 250 km to 66,000 km above Venus as it carries out the most comprehensive study ever of its atmosphere.
Scientists say they hope the EUR 220 M mission will reveal the meteorological and atmospheric processes at work above the planet.