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We're standing in a room in which men and women have helped execute one of the greatest space manoeuvres in all of human history; the awakening of the Rosetta probe.

'The 45 minutes before the signal from Rosetta was the toughest in my life,' mission director Paolo Ferri says. 'I never want to go through that again.'

But next week, Ferri and his team will have to undergo an even more excruciating wait – this time for seven hours - as they attempt to land Rosetta's Philae probe on an icy comet.

Scroll down for video and animation 

Emotions in the control room can run high. During launches, a moodily-lit space (pictured) with curved consoles facing the main screens, is staffed by specialists responsible for different parts of Rosetta

Rosetta has chased comet 67P/Churyumov–Gerasimenko through space for more than ten years in what has been described as 'the sexiest, most fantastic mission ever',

After a four billion mile (6.5 billion km) journey, the spacecraft is now just 19 miles (30 km) away from the 67P - and on Wednesday will attempt to send a probe to land on its craggy surface.

Tensions have been mounting in recent months at mission control. But today, other than a few engineers talking fervently in a corner, the German space center seems oddly quiet.

'It might not look like it,' says Ferri, 'but there is a lot going on.' 

Clocks on every wall are on a relentless march to zero – a time that will coincide with 08:35 GMT on the 12th of November.

The daring descent Philae (artist's impression shown) will take seven hours from separation. It will be exactly nine years that a similar landing attempt on an asteroid by Japan's Hayabusa failed in 2005

On that day, the world's media and dignitaries will be descend on the sleepy city of Darmstadt to watch Philae's daring landing. 

As morning approaches, Ferri and his team will take their positions at a spaceship-style control center from which the fate of more than two decades of research will be decided in just seven hours.

Emotions are already running high. 'This, for me, is a wonderful dream come true,' said Ferri. 'Just thinking about it…I have tears in my eyes. 

'You spend a lot of your time in very odd situations with [Rosetta], working weekends, and getting calls in the middle of the night. It's not fair to compare it to a relationship with a human, but it's very close.' 

When it was launched in 2004, Rosetta was so far from 67P that it had to pass Earth three times and Mars once, so that it could use their gravity to slingshot its way deep into the solar system.

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The spacecraft will spend more than a year studying the comet, which is made up of material left over from when planets were first created 4.5 million years ago.

The Philae probe aims to analyse the comet in more details. The results, Esa claims, could completely rewrite the history of the solar system.

It's an incredibly complex feat that has never been attempted. 'Imagine the comet as Mont Blanc,' said Ferri.

'You fly with an aircraft at 13.6 miles (22km) in altitude – so twice the altitude of a normal airline. At a certain point you have to drop a box and hope that it lands on the mountain within a square km.'

José Luis Pellon-Bailon is one of eight flight engineers responsible for Philae's descent. The team is fully prepared, he says, and has even planned out what they'll eat on the day.

Peanuts are crucial. 'We found out that people at Nasa eat peanuts on the day of the special activity. In a mission that is problematic, they will always have peanuts on the table.' 

Esa has inherited the superstition, and Ferri confirms that it's vital to the success of the mission. 'I'll also be wearing the same tie I wore when Rosetta launched ten years ago,' he says. 

Zoom in on the image below to find out where Rosetta is at the moment 

Rosetta took an incredible selfie of its 131ft (40 metre) solar wings gleaming against the darkness of space. In the background is the comet, Comet 67P/Churyumov-Gerasimenko, with its 'head' and 'body' clearly visible

The bizarre rituals at mission control are hoped to steady nerves as engineers perform complex manoeuvres around the comet.

As Philae descends, it will be travelling at walking speed of 3ft (one metre) per second relative to the comet while the duck-shaped mountain is rotating constantly. 

Philae will need to be released with pinpoint accuracy as its landing site contains a mix of sheer cliffs and deep craters– any of which could scupper its chances.

Scientists are aiming to land on a spot named 'Agilkia' on the smaller 'head' lobe of 67P. Philae will be released from a distance of 14 miles (22.5km) from the centre of 67P.

Pellon-Bailon explains his team will have to make a series of Go or No-Go decisions before the landing.

If the green light is given, communication between Rosetta and mission control will take 28 minutes and 20 seconds each way – the time it takes for a signal to travel 315 million miles (510 million km) to Earth. 

Rosetta's target comet, 67P/Churyumov–Gerasimenko, is about 2.48 miles (4km) wide. Here it is shown alongside some of Earth's landmark

Rosetta spacecraft: Story of the comet-chaser

Paolo Ferri, head of Esa Operations, is overjoyed after receiving Rosetta's acquisition of signal in January

'It's difficult, in the sense that you are commanding something and you are seeing the effects almost one hour later,' said Pellon-Bailon. 'If we land on the comet, it will be very emotional.'

If Philae doesn't make it, those emotions will have to be kept in check. The mission control team take part in simulations designed to make the team panic, frustrated, angry and upset.

'I always compare it to an orchestra,' said Ferri. 'Every person is a master of their instrument, but you still have to train to play together. 

'When I'm in a simulation I think I'm in the real thing. I get as excited, and I sweat and, I'm very good at that. It happens in simulations, people go mad…In real life we can't afford to lose control.'

Ferri's biggest fear isn't that Philae will be damaged during the descent, but that it could fail to send a signal back.

TOUCHDOWN ON THE COMET: PHILAE'S DETAILED LANDING TIMELINE 

Rosetta will release Philae at 08:35 GMT/09:35 CET on 12 November at a distance. Pictured is an artist's impression of the lander on Comet 67P

Rosetta will release Philae at 08:35 GMT/09:35 CET on 12 November at a distance of  14 miles (22.5km) from the centre of the comet.

The landing will be about seven hours later at around 15:30 GMT/16:30 CET.

During the descent, Philae will take images and conduct science experiments, sampling the dust, gas and plasma environment close to the comet.

It will take a 'farewell' image of the Rosetta orbiter shortly after separation, along with a number of images as it approaches the comet surface.

It is expected that the first images from this sequence will be received on Earth several hours after separation.

Once safely on the surface, Philae will take a panorama of its surroundings. Again, this is expected back on Earth several hours later.

The first sequence of surface science experiments will begin about an hour after touchdown and will last for 64 hours, constrained by the lander's primary battery lifetime.

Longer-term study of the comet by Philae will depend on for how long and how well the batteries are able to recharge, which is related to the amount of dust that settles on its solar panels.

It is expected that by March 2015, as the comet moves closer in its orbit towards the sun, temperatures inside the lander will have reached levels too high to continue operations, and Philae's science mission will come to an end.

But the Rosetta orbiter's mission will continue for much longer. It will accompany the comet as it grows in activity until their closest approach to the sun in August 2015 and then as they head back towards the outer solar system. 

Tensions have been mounting in recent months at mission control (pictured). But in the days leading up to Philae's historic landing, the German space center seems oddly quiet

'This would be a huge disappointment,' he says. 'Of course, the landing mission would be off, but also we wouldn't have learned why.'

Pellon-Bailon says when he first got involved in the mission in the early 1990s, it sounded to him like science fiction. Even now, he can't quite believe they've reached the comet. 

'It sounds crazy when you say it out loud,' says Ferri. 'Sometimes I sit back and think, there's a two cubic metre box flying half a billion kilometres away, that is now sending a very faint signal.

'That signal is picked up in Australia, and now I'm looking at it. Then I think, how is it possible?'

But it has been possible, and even if Philae doesn't make it on Wednesday, the mission has alreadt achieved its main objective. 

'You have to remember, and we have to remember, this landing is spectacular, but it is only one part of the mission,' says Ferri.

'Whatever happens, data from Rosetta has already rewritten the history of our solar system.' 

The reconstructed-colour image, taken early October, indicates how dark the comet appears. On the average, the comet's surface reflects about four per cent of impinging visible light, making it as dark as coal