Very similar to Earth in size and mass, Venus was expected to be very similar to our planet when the first Russian and American space probes approached it in the early 1960s and started returning the first data about its atmosphere.
Observers soon realised that Venus is an entirely different, exotic and inhospitable world, hidden behind a curtain of dense clouds of noxious gases. It has an atmosphere mainly composed of carbon dioxide, with crushing surface pressure and burning-hot temperatures.
Then the question arose: why did a planet apparently so similar to Earth evolve in a way so radically different over the last four thousand million years?
Up to the mid 1990s, many ground observatories and more than 20 spacecraft had attempted to explore Venus. A set of orbiters and descent probes - the Soviet Venera series and the Vega balloons and landers, the US Mariner, Pioneer Venus and the Magellan missions - tried to penetrate this hostile world to add pieces to the big puzzle that Venus represented for scientists.
Many missions were lost, many landers were destroyed under the high pressure and temperature of the Venusian atmosphere while providing the first information about the planet. It is still due to such a dense atmosphere with thick cloud cover that, for years, scientists were prevented from seeing what lays below and from understanding the nature of the Venusian surface.
Only when modern radar imaging systems became operational on space probes and ground observatories, did the first glimpses of the real face of Venus started to emerge.
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| | Looking at Venus (http://www.esa.int/SPECIALS/Venus_Express/index.html) |
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 Launch replay

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| | Venus Express launch (mms://esawms.cdnetworks.net/esawms/wmv/Venus_Express_launch_low.wmv) |
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 Related articles

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| | Venus Express performs flawlessly, LEOP complete (http://www.esa.int/SPECIALS/Venus_Express/SEMK9UJBWFE_0.html) |
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| | Venus Express mission operations update (http://www.esa.int/SPECIALS/ESOC/SEM780738FE_0.html) |
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| | "Venus Express, give me a GO/NO GO for launch..." (http://www.esa.int/SPECIALS/Venus_Express/SEM6SV638FE_0.html) |
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| | Venus Express: ready for lift-off (http://www.esa.int/SPECIALS/Venus_Express/SEMAWL638FE_0.html) |
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| | Green light for Venus Express launcher fuelling (http://www.esa.int/SPECIALS/Venus_Express/SEMJVL638FE_0.html) |
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| | Venus Express countdown activities started (http://www.esa.int/SPECIALS/Venus_Express/SEM93L638FE_0.html) |
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| | Venus Express moved back to launch pad (http://www.esa.int/SPECIALS/Venus_Express/SEM24K638FE_0.html) |
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| | Venus Express set for transport to launcher assembly building (http://www.esa.int/SPECIALS/Venus_Express/SEM1BB6Y3EE_0.html) |
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| | Venus Express mated with upper-stage (http://www.esa.int/SPECIALS/Venus_Express/SEMTYW5Y3EE_0.html) |
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 More about...

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| | Status reports (http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=31575 &farchive_objecttypeid=30 &farchive_objectid=30930) |
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| | Launch in detail (http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=31574 &farchive_objecttypeid=31 &farchive_objectid=30928) |
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| | Venus Express factsheet (http://www.esa.int/SPECIALS/Venus_Express/SEM2EE1A6BD_0.html) |
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 Related links

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| | Starsem - the Soyuz (http://www.starsem.com/) |
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| | Venus Express operations (http://www.esa.int/SPECIALS/Operations/SEM7QMQJNVE_0.html) |
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| | Cebreros station webcam (http://www.esa.int/SPECIALS/Operations/SEM26DSMTWE_0.html) |
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