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One of Europe's most successful spacecraft has gone gently into the silent night around the hottest planet in the solar system.

Since 2006 Venus Express had been studying the second world from the sun in unprecedented detail, revealing - among many discoveries - that the planet may still be geologically active.

But Esa has revealed that the spacecraft has now run out of fuel, bringing to a close this flagship European mission - and leaving Venus without any spacecraft in orbit.

Esa in Paris has confirmed that its Venus Express spacecraft (illustrated) has died. The probe had been orbiting Venus for eight years since 11 April 2006 - far exceeding its original planned lifetime of under two years. But it finally run out fuel during a series of daring atmospheric manoeuvres

Venus Express was launched back on 9 November 2005 and arrived at Venus on 11 April 2006.

It was one of the longest-serving spacecraft to orbit the planet, despite initial estimates for the mission expecting it to last not even two years.

Now it seems time has caught up with the spacecraft, though, as it has finally run out of fuel - which means contact cannot be made with it any more, as its antenna cannot be pointed towards Earth.

Although it had far exceeded its planned life, scientists had recently been preforming a series of daring manoeuvres deep into the Venusian atmosphere as the spacecraft ran out of fuel.

Unlike cars and aircraft, spacecraft are not equipped with fuel gauges, so the time of propellant exhaustion for any satellite - especially after such a long time in space - is difficult to predict.

However, while the end could not be predicted, it was not completely unexpected as it was known the spacecraft would be running low on fuel.

Full contact with Venus Express was lost on 28 November. Since then some communications had been partially re-established, but they were very unstable and only limited information could be retrieved.

Without propellant, there is no chance of restarting communications.

It is also impossible to raise the altitude further, meaning that the spacecraft will naturally sink deeper into the atmosphere over the coming weeks and ultimately burn up in the atmosphere of Venus.

'The available information provides evidence of the spacecraft losing attitude control most likely due to thrust problems during the raising manoeuvres,' said Patrick Martin, Esa's Venus Express mission manager.

'It seems likely, therefore, that Venus Express exhausted its remaining propellant about half way through the planned manoeuvres last month.'

Adam Williams, Esa's acting Venus Express spacecraft operations manager, added that they knew the spacecraft was 'running on fumes' but they were pleased to push the boundaries 'right down to the last drop'.

Venus Express can no longer re-position itself to communicate with Earth. However, the mission was hugely successful, revealing that Venus (shown) may still be geologically active - and also revealing increasing wind speeds in its atmosphere over just six years

In a few weeks the spacecraft will go out in a 'blaze of glory' as it silently plunges into the Venusian atmosphere (illustration shown). It ran out of fuel as it was performing lower and lower drops into the atmosphere in a bid to glean more science before the mission ended

However, despite now coming to a conclusion end, the mission returned some key science in its eight years around the planet.

'While the science collection phase of the mission is now complete, the data will keep the scientific community busy for many years to come,' said Håkan Svedhem, Esa's Venus Express project scientist. 

One highlight from the mission was the tantalising hint that the planet may still be geologically active today.

A study found numerous lava flows that must have been created no more than 2.5 million years ago - just yesterday on geological timescales - and possibly even much less than that.

And even though the conditions on the surface of Venus are extremely inhospitable today, a survey of the amount of hydrogen and deuterium in the atmosphere suggests that Venus once had a lot of water in the atmosphere, which is now mostly gone, and possibly even oceans of water like Earth's.

Studies of the planet's 'super-rotating' atmosphere - it whips around the planet in only four Earth-days, much faster than the 243 days the planet takes to complete one rotation about its axis - also turned up some intriguing surprises.

When studying the winds, by tracking clouds in images, average wind speeds were found to have increased from roughly 185 to 250 mph (300 to 400 km/h) over a period of six Earth years.

At the same time, a separate study found that the rotation of the planet had slowed by 6.5 minutes since Nasa's Magellan measured it before completing its five-year mission at Venus 20 years ago.

However, it remains unknown if there is a direct relationship between the increasing wind speeds and the slowing rotation.

A study using data from Venus Express found numerous lava flows that must have been created no more than 2.5 million years ago (illustration of the Venusian surface shown) - just yesterday on geological timescales - and possibly even much less than that

'Venus Express has been part of our family of spacecraft in orbit since it was launched in 2005,' says Paolo Ferri, Head of Esa Mission Operations.

'It has been an exciting experience to operate this marvellous spacecraft in the Venus environment. The scientific success of the mission is a great reward for the work done by the operations teams and makes us more proud than sad in this moment of farewell.'

And Martin Kessler, Head of Esa Science Operations, added: 'While we are sad that this mission is ended, we are nevertheless happy to reflect on the great success of Venus Express as part of Esa's planetary science programme and are confident that its data will remain important legacy for quite some time to come.

'The mission has continued for much longer than its planned lifetime and it will now soon go out in a blaze of glory.'