The European-built Venus Express spacecraft successfully went into orbit around Earth's closest planetary neighbour after a five-month journey, ground controllers said Tuesday.
"Everything went as it was planned, clearly, without difficulties," Gaele Winters, director of operations at the European Space Agency, told a news conference at mission control in Darmstadt, Germany.
"This is a great success."
Its mission is to find about the greenhouse effect – the way carbon dioxide traps the sun's heat on Venus – and to help scientists draw comparisons with global warming on Earth.
Both planets have similar sizes and compositions, but Venus evolved differently and is showing much stronger effects of global warming.
"If we can understand those [differences], then it makes it easier for us to understand how the Earth might evolve in the future, for example into this unknown state that we're facing as the climate changes," said Prof. Fred Taylor of Oxford University.
The spacecraft will repeatedly orbit Venus, measuring the chemical makeup and other elements of the atmosphere. It will also take photos of the clouds and planet.
The average temperature on Venus is 477 C – hot enough to melt lead.
The planet's toxic atmosphere is mainly composed of carbon dioxide, with clouds of sulphuric acid and winds whipping up to 400 kilometres per hour.
1st images expected within days
The Venus Express probe is well equipped to carry on its mission, said Don McCoy, a Canadian aerospace engineer who is managing the project.
"We probably have enough fuel to do the extended mission, one year and a half, for 468 days," said McCoy, who works for the European Space Agency.
The first images of the south pole of Venus could be returned as soon as Thursday, space officials said.Venus Express resembles the Mars Express spacecraft that is orbiting the Red Planet.