As Britain's first official, government-backed astronaut, his selection for a mission in late 2015 marks a pivotal moment.

Countries as far afield as Belgium, Mexico and Vietnam have already had people in space, but so far the only Brits to make it have either had to change nationality (and become American) or win a Russian competition (as in the case of Helen Sharman in 1991).

For decades, British governments regarded astronauts as a rather strange and pointless luxury - the weightless floating about irrelevant to life on the ground and the costs far too extravagant to contemplate.

This attitude was memorably summed up by Kenneth Clarke in the last Conservative government in the 1980s. When asked if Britain would contribute to the European Space Agency's role in the International Space Station, he replied that he didn't want to pay to put a Frenchman in space.

Since then, quietly and modestly, British space labs and companies have grown to become market leaders in key technologies and their business is valued at £9bn a year.

The sensors that bring you those amazing pictures of the Sun, the rocket motors steering spacecraft, the harpoons that may help clear up space junk - many are designed and built in Britain.

There are hopes that the space sector will grow - eventually to support as many as 100,000 jobs - and the figurehead of this renewed British effort in space is a former helicopter pilot from Chichester.

Science Minister David Willetts regards the £16m to secure Tim Peake's ticket as money well spent.

While Nasa wraps its astronauts in the rhetoric of fabled explorers - lots of "celestial destiny" and "bold endeavour" - the British take is far more mundane: the press release announcing Tim Peake's mission is mainly about British industry and jobs.

So when he dons his spacesuit, and checks the union flag's in place, there'll be a lot riding on his multi-layered shoulders.

I first met him when he was picked for the European Space Agency's astronaut corps back in 2009 - the start of a long road to orbit - and he appeared exactly how you expect astronauts to look: calm, measured, ready for anything.

He's got the straight spine of a military man and the sharp gaze that Nasa selectors have always favoured, and he turns his head in even, steady moves, not unlike those chisel-jawed heroes of Thunderbirds.

On Monday morning, after his news conference, his cheeks were flushed in a way that reminded me of Prince Harry, and his manner has the same relaxed air.

"I'm clearly delighted with the decision. It's a true privilege to be assigned to a long-duration space mission," he told me.

I asked about the much-pushed angle that his mission is partly about trying to boost economic growth.

"There's also the inspiration part - the true human exploration in terms of what we are doing.

"We are pushing the boundaries every time an astronaut goes up; we learn new things about ourselves, about our bodies."

Then the really big questions: yes, he does play the guitar, not well, but did actually once play with the legendary Chris Hadfield, the most musically famous astronaut of them all.

Via Twitter, I was asked if Tim Peake would introduce his fellow astronauts to the delights of a Full English Breakfast.

"I get to choose some of the European food that comes up with me, so a Full English breakfast might be top of the list."

So in November 2015, at the desert launch complex at Baikonur that saw Yuri Gargarin blaze a trail into orbit, Tim Peake will climb into the top of a Soyuz rocket.

The countdown will be in Russian. Tim Peake's training will make him comfortable with the language. And then the first jolt of launch will kick in.

Down below him, a blast of flame will send a wall of heat across the scrubby dunes towards the viewing stands and camera positions: this will make compulsive viewing in homes and schools across Britain.

Tim Peake will be given a vigorous shaking - "a moment nothing can prepare you for", he told me - as the rocket motors accelerate him into space, and a place in the history books.

While Nasa wraps its astronauts in the rhetoric of fabled explorers - lots of "celestial destiny" and "bold endeavour" - the British take is far more mundane: the press release announcing Tim Peake's mission is mainly about British industry and jobs.

So when he dons his spacesuit, and checks the union flag's in place, there'll be a lot riding on his multi-layered shoulders.

Confused? If so, you're not alone.

The future of sea level rise is one of the most important questions in climate science because so many millions around the world live beside coasts - but it's also one of the most difficult to answer.

One of the authors of a new study, published today, even described the uncertainties of the field with that memorable phrase first coined by the former US defence secretary Donald Rumsfeld: "unknown unknowns".

Not everyone is always so open about this.

I'll never forget a video screened at the opening session of the UN's climate talks in Copenhagen in 2009 - the conference that got nowhere - which portrayed this issue at its most simplistic.

One scene showed a vast flood that left a little girl hanging from a tree screaming her heart out.

The message to delegates was crude: "If you don't negotiate a climate deal, the kid gets it".

I reported at the time that nothing in the scientific literature was specific enough to justify this lurid threat.

In the event, none of the major players was paying attention to this climate horror show anyway and there was no treaty.

So what did the science say back then and what does it say now?

The last major report by the UN's Intergovernmental Panel on Climate Change (IPCC), its Fourth Assessment Report published in 2007, concluded that the global average level of the sea may rise by between 18cm-59cm.

Much of that was expected to come from what's called "thermal expansion" - the physical process by which the volume of a body of water expands as it warms, as the oceans are.

But, crucially, the IPCC said that not enough was known about the other great potential contributor to sea level rise - the melting of the polar ice sheets and glaciers.

Polar melting has been a kind of wild card in these calculations: a sudden acceleration in melting could cross some hidden threshold and trigger runaway melting that would cause an unexpected surge. Or not.

To try to fill that gap in the knowledge, a leading British polar researcher, Professor David Vaughan of the British Antarctic Survey, and teams of colleagues came together in a consortium called Ice2sea.

So what does the new study tell us? The headline is that forecasts of the changes to the ice-sheets and glaciers in the Arctic and Antarctic suggest their melting could contribute between 3cm-36cm to sea level rise.

This would add another 10cm to the upper range of the last IPCC forecast.

This perhaps does not sound like much of a change - and the range in numbers is still pretty large spanning from "not very much at all" to "quite a bit".

But Prof Vaughan and others say the estimate is much more robust than earlier ones and provides more clarity for policy-makers.

In any case a rise on slightly larger bigger scale would of course be serious for communities in low-lying countries. I saw for myself how most the tiny island nation of Tuvalu is already only 2-3m above sea-level.

The challenge with all forecasts - especially on this question - is that they rely on a whole series of factors and assumptions.

The Ice2sea researchers started with a global climate model that assumed a particular scenario for the rise in greenhouse gases. It then used further models to investigate the potential change in climate in regions such as Greenland and Antarctica.

Another layer of computer simulations explored how the ice might respond. Final stages investigated what that could mean for sea level not just globally but also on particular coasts.

Hence the large range of possible outcomes.

On top of that, the ice-sheets and glaciers themselves are often inaccessible and hard to measure. One research effort even involved firing hi-tech javelins at a glacier in Antarctica.

And satellite data only stretches back a few decades.

Interestingly, one conclusion is that the very scariest scenarios look less likely.

There is only a one in 20 chance, they reckon, that by 2100 coastal towns in the Thames Estuary, Holland and Ireland may get hit by extreme surges about one metre higher than now.

At a media briefing, I asked what that meant and whether we could take it that there's a 95% chance that this won't be what happens. That's right, I'm told. The very gloomiest warnings look far less plausible.

The most certain piece of knowledge is that the global average sea level has been rising by about 3mm a year.

But what really matters is whether this will accelerate - and by how much. And all that's still a work in progress.

At the top, above 11,000ft, the air is thin and the sun piercing. During my visit, I watched rain clouds boiling in the valleys below me. Charles David Keeling chose this otherworldly spot because the air up here is neither industrial nor pristine; it is "well-mixed" which means it can serve as a useful guide to changes in the atmosphere.

Despite their global significance, the devices he installed back in 1958 do not look impressive. But he battled bureaucratic objections to fund them and his legacy is the longest continuous record of a gas, linked to much of global warming, that just keeps rising.

The pieces of tusk were so numerous that a total of 79 elephants had been slaughtered to yield this haul destined for the remorseless markets of China.

The smell was indeed funereal: musty, pungent, depressing.

So much about the endless plunder of wildlife around the world - and the apparent failure of international agreements to stem the losses - is a cause for despondency.

Cross-border policing efforts are being stepped up but all too often the police themselves are involved in the trade. The money is easy and the pickings rich.

It's far easier to kill elephants, tigers and gorillas than to save them.

So it's always uplifting to hear stories about the handful of people brave enough to stand up and intervene. They have a lot stacked against them: indifferent or corrupt authorities, powerful criminal gangs, long-held traditions about how to make a living.

One of the plucky few is from Cameroon. Ekwoge Enang Abwe runs a project to try to safeguard the creatures of the Ebo Forest: the gorillas, chimpanzees and monkeys that are pillaged for bushmeat. Unchecked, the trade would wipe them out.

I met Ekwoge through a small conservation charity, the Whitley Fund for Nature. He is one of eight winners of this year's Whitley Awards (Read more about the winners here).

His challenge was to confront an entire economic system based on exploiting the forest for its animals. As many as 2,000 were being killed every week as traders from the cities brought traps and ammunition to equip the hunters for their grim ventures into the jungle.

How could he possibly hope to turn this around?

"Pride," he told me. "We've been appealing to the sense of pride of the communities. We used pride as a tool.

"We explained to them how the animals are special, how they're often unique, and that they could have a role in saving them."

Only 25 gorillas, from a sub-species, are left in the forest. The chimps are the only ones known both to fish for termites and use rocks to crack nuts. The Preuss's Red Colobus monkeys only live in one other habitat.

"So we educate the people and the chiefs about how special these animals are and how alternative livelihoods are possible."

The hunters have been encouraged to turn to cocoa farming. The chiefs have come together from previously divided clans to discuss setting up systems for keeping watch on poachers. A census of gun holders will take place.

Ekwoge's hope is that the forest will be granted the status of a National Park, a move which would give it more protection. National government does have a role but the impetus is local. And without a change in local attitudes - a revolution in thinking about the natural world's value - none of this would have been possible.

Another winner, Daniel Letoiye, a Samburu from Kenya, also says that the decisive factor is the support of his local community. His project is to restore the grasslands left barren by years of drought and overgrazing.

Initially his plan to reseed particular areas - and to keep the cattle away for up to three months - was met with hostility.

"There was a lot of opposition. People were saying, 'Why are you taking our land?' They didn't like the idea at all," Daniel recalls.

But after the first year when the grasses started to return, people saw the logic of agreeing to rotate the animals. The plans made sense.

And having healthier pastures allows native animals to recover too. Grevy's Zebras - notable for their relatively large size, narrow stripes and large ears - are down to just 2,400.

Continued degradation of the land and poaching would have finished them off. A traditional belief was that the zebras' fat was effective medicinally.

"A big theme is co-existence," says Daniel. "We have shown that the zebras can co-exist with the cattle and the tourism brings in an income of $80,000 a year."

Projects like these are chinks of light in an otherwise pretty gloomy international picture. Other winners include the people behind Turkey's first wildlife corridor and marine reserve, and schemes to save hornbills in India, turtles in Bangladesh, gorillas in Congo and wildlife in the headwaters of the Amur River.

They win £25,000 each - not a huge amount, but enough to help raise their profiles enough to start attracting political support.

For the Trust's founder, Edward Whitley, an important feature is that the initiatives are not imposed by "experts" flying in from outside.

He describes being dismayed by the sight in Madagascar of "the gleaming white Landcruisers of the international community" and wants to give local "heroes of conservation a leg-up".

It'll take more than this to halt the wildlife horror stories in so many countries. But after inhaling the stench from one of those crates full of smuggled ivory, it's a very welcome start.

Nor could they have predicted that a web-based debate would have explored the apparently outlandish idea of volunteers travelling on a one-way ticket to Mars and setting up a colony with no prospect of return - all on live television.

The technology for that kind of space travel didn't exist back then. The TV show Big Brother hadn't been invented. And the three letters "www" were known to only a handful of people.

But on Tuesday afternoon, in a Google "hangout" - the first of this type of web-based dialogue to be hosted by BBC News - contributors from as far afield as Arizona, Paris and Mumbai shared their thoughts with us in London on a plan for an outpost where people would live - and die - beyond Earth.

A Dutch organisation, Mars One, is seeking volunteers for a flight that would take them to the Red Planet and leave them there. The costs would be covered, it's hoped, by TV rights and corporate sponsorship.

There is something about Mars that catches the imagination - its bloody colour, its role in mythology, the terrible track record of attempts to land on its distant and dusty surface, and the prospects of finding forms of alien life.

I checked with Bas Lansdorp, boss of Mars One, for the latest number of people to sign up so far: 30,000 people had paid the 30 euro deposit by the end of last week - and that number is probably far higher now.

Applicants' videos on his website capture an extraordinary level of excitement about the chance of making the journey. So what is it that drives people to want to leave this planet and risk everything on another?

We discussed that question with Melissa Ede, who describes herself as a transgender woman, and has signed up as a contender to be selected for the Mars One mission - "failure isn't in my vocabulary", she told us before the webcast.

For her, it was about excitement and the need to explore. "How do we know it's not possible?" she asked.

That was in response to comments I'd made about the very high number of very large obstacles that need to be overcome before anyone's boots will scuff the soils of Mars.

For a start, space is difficult and expensive. There aren't colonies on the Moon or Mars right now for a reason: the challenges and costs are huge.

The preferred rocket, Falcon Heavy, has to yet to be tested by its makers, SpaceX, even though the Mars One plan calls for the first demonstration flight to land on Mars in 2016.

A satellite is due to be parked above Mars in the same year to act as a relay for live TV pictures. A British firm, Surrey Satellites, confirms to me that it has been approached by Mars One but says it needs to be paid before researching the proposal.

The Mars One plan has incredibly tight timings - possibly unrealistically tight. Various contributors agreed on the sheer scale of the technological difficulties, including Rajat Agrawal, a technology writer in Mumbai, and Amy Shira Teitel, a space historian in Phoenix.

Ms Shira Teital said: "What if one of their supplies ships doesn't make it and they lose food? What's going to happen when vital parts don't make it or survive the trip? Is the crew going to eat each other? How much are we willing to make it a 'Lord of the Flies'-type situation if it all goes terribly wrong?"

Meanwhile, another communications system only made possible by the Web - Twitter - focused on the apparently appealing notion of using Mars One to rid the Earth of various people - usually politicians. One said: "You would never have to hear Justin Bieber again."

Others asked about the practicalities, often the grim ones. "What happens to the corpses?" asked one woman in a Tweet. Fair question, and thought-provoking: colonies need cemeteries.

There's always massive interest in Nasa's rovers on Mars - and robots like Curiosity are a very efficient way to explore the solar system. But there's nothing like the prospect of humans venturing there to spark excitement.

The half hour hangout passed incredibly quickly. I was reminded - by an email - of an earlier venture, Mars Express, the European Space Agency's spacecraft sent to orbit Mars.

I witnessed its launch from Baikonur in Central Asia in June 2003 - almost 10 years ago. It was an uplifting sight watching the rocket blaze its way through space and the mission was a success.

But the craft was also carrying a tiny lander, the British Beagle-2, which was designed to touch down and search for signs of life. On Christmas Day, 2003, we waited for a signal - and waited and waited. The Beagle had crashed.

Imagine the risks of a manned mission to Mars, and the tension of a landing. If it gets off the ground - and it's a very big if - Mars One would provide irresistible viewing. And a lot more for us all to talk about.

After spending the winter inland in Finnmark, Europe's last great wilderness, the animals are moved to pastures near the coast for the summer.

The reindeer play a central role in the livelihoods and culture of the indigenous people of the region, the Sami, but this way of life is under pressure, as I saw on a journey in northern Norway earlier this month.

Look at a map of the region and you'll see very few roads and only a handful of towns. Our expedition of nine people, each towed by a team of huskies, hardly encountered another soul.

Led by our guide, Tom Frode Johansen, we passed through valleys and over hills, along the border between Norway and Finland, and then across frozen lakes and uplands of unblemished white.

When it was cloudy - or when there were flurries of snow - the landscape appeared almost lunar and barren, and it was impossible to imagine any kind of animals enduring here.

But when the sun came out, a golden light would transform the scene, revealing the details of cliffs, streams, clumps of woodland and - most significantly - herds of reindeer.

Brown and sturdy, their antlers silhouetted against the white, the reindeer clear away the snow to reach the food they rely on in winter: lichen. It does not seem to amount to much but it does mean that life is possible here.

And one night we saw how central the reindeer are to the lives of the Sami people.

We had been on the move for 12 hours and shelter from the cold couldn't come soon enough.

It was well below freezing and the snow was so deep that we sank into it past our knees.

A tiny glimmer of light shone from the window of a hut ahead of us. This was to be our sanctuary.

Our torches picked out the wooden walls of the small building; otherwise we were in a landscape so empty it was hard to remember that Finnmark is part of the overcrowded continent of Europe. My mobile phone hadn't had a signal all day.

As soon as we walked in, our host, Ellen-Anna Siri, welcomed us with an enormous dish of stew - of reindeer meat, of course - and exactly what we needed.

For breakfast the next day she and her mother Kristine offered a plate of dried reindeer heart which was also delicious.

And the two of them couldn't resist dressing my daughter Kitty in the full traditional Sami woman's costume of reindeer leather and embroidered hat.

The connection between the Sami people and their reindeer has been about survival in a hostile land and it runs very deep: there is a legacy lasting millennia of living together in the polar North.

The most immediate threat, we were told, is from wolves, bears and wolverines.

Attracted by the reindeer herds, these predators are highly aggressive so Ellen-Anna warned us about going outside at night.

If you need to go to the toilet, she said, which involved walking quite a distance through the snow, make sure you're accompanied so someone can keep a lookout.

Suddenly, the wilderness seemed very wild indeed.

But for the Sami this is nothing compared to the fundamental challenges they have faced.

Historically, as semi-nomads, they have been irritating to the various governments here.

For years Norway tried to make the Sami people more Norwegian. And along with Finland, Sweden and Russia, Norway closed its borders at various times, blocking the annual migrations.

In the Second World War, when the Nazis were driven back by the Soviet Army, the Sami suffered terribly.

Then the nuclear accident at Chernobyl in 1986 released a radioactive cloud which contaminated thousands of reindeer.

More recently, with rising temperatures in the Arctic, the Sami say the shorter winters are forcing them to change the patterns of their herding.

On top of that, the grazing lands are under constant pressure from developers and prospectors who are lured by deposits of gold, copper and iron ore.

Reindeer herding is no longer the only possible activity in these snowy lands.

Inevitably, there has been a drift to the cities, to an easier life; traditional cultures experience that loss the world over. But the Sami are showing a powerful streak of resistance.

At our destination, Kautokeino, a town regarded as a Sami capital (with a parliament and university), we watched a kind of Sami Olympics.

People had travelled from across the region to be there and the games attracted a lively mix of accents and languages.

The highlight was the reindeer racing, the animals tugging youngsters on skis at incredible speed.

Later there was a full house for a competition for 'yoiking': yoiks are songs of praise, highly personal and often haunting. I found one sung to a daughter particularly moving.

But then a band struck up. Yoiks have had an electronic makeover that's given them the sound of something from the Eurovision song contest.

My first thought was that Sami culture could easily drown in a sea of light pop; but then I wondered if this was actually a clever way of keeping alive an age-old practice.

I stepped outside into the bitter cold. Above me a vast green stripe arced across the sky: it was the mesmerising sight of the Northern Lights, strangely shaped clouds glowing and twisting from horizon to horizon.

It occurred to me that the Sami people are among the very few to live under this spectacular show; and their ancestors must have enjoyed it too.

Somehow the Sami have adapted and coped and survived over thousands of years, each generation gazing up at the swirling luminous skies while warming their hands on a bowl of reindeer stew.

Learn more about the Sami people by listening to David Shukman's report from Scandinavia on From Our Own Correspondent .

But I ask because I am merely wondering whether we sometimes forget a grim reality of the story of life on Earth - that extinction has always been with us.

In fact, it has quite often been good for us.

We are certainly far better off without velociraptors slashing their way through our cities. Our streets are safer with no sabre-toothed tigers. And imagine trying to swat one of those monster prehistoric insects like a vulture-sized dragonfly.

The question of extinction most recently surfaced at the talks on the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) - the treaty meant to save endangered species from the devastating effects of trade.

The slaughter of rhino, the decimation of elephant, the forlorn last stand of the tiger - all had their profiles raised as the delegates in Bangkok negotiated their fate.

BBC News: The Editors is a monthly programme on BBC One which brings together the BBC's on-air editors, each a specialist in their field, to answer some of the big questions about what's happening in the world. It is also on BBC World News.

BBC News: The Editors

And anyone hearing the protests and the campaigns, and the shocking statistics about the losses, might be forgiven for thinking that extinction was some new kind of evil that was not invented until rapacious and uncaring mankind came along.

I should state right now that some of the most ghastly examples are indeed entirely the result of man's activities, sometimes unwittingly, sometimes carelessly.

However, taking a long view, extinction has been part of the natural order of things throughout Earth's history.

The most famous mass wipe-out was the loss of the dinosaurs. And four other great die-offs have been identified - one of them killing off something like 90% of species.

But there is so-called "background" extinction as well - species fading out year by year, creatures quietly losing out to others and disappearing. These losses might not be spectacular - in fact, they're routine.

The result is that the average species only lasts a few million years. Mammals do worst, surviving between one and two million years. Clams do better at five to seven million.

A few hardy survivors - the leatherback turtle is a prime example of a sturdy design - cling on for tens of millions of years.

But the blunt truth is that the living world is a restless, churning enterprise in which nothing endures forever. Astonishingly, almost every life form that has ever existed on the planet has died out.

It is worth pausing to absorb what that means. Something like 90% - or even 99%, according to some estimates - of every kind of sea creature or land animal or insect or plant that enjoyed a spell on Earth then vanished into oblivion.

Some remains morphed into fossils and ended up on the shelves of museums. Others have left no trace.

Charles Darwin wrote of extinction in his landmark On the Origin of Species.

For him, the process of evolution involved new species gaining ground and others losing out. He certainly did not mourn the passing of the losers.

So, in the clamour to conserve a host of iconic species, is there a case for us to be more realistic about our ability to intervene? Might the awkward fact be that we can't save everything?

It is certainly the case that the creatures with the best chance are those whose looks or adorability or loveable eyes have attracted the strongest support. No-one is fighting to save the tubeworm.

But should the emphasis change if extinctions are our fault? Or, worse than that, if the losses are accelerating because of us - by tearing up habitats or causing pollution or simply slaughtering every member of a species?

There is a long list of animals whose disappearance can be blamed squarely on human actions.

I met one of them on the Galapagos Islands a few years ago - Lonesome George, the last giant tortoise of his species, a lumbering, sad-eyed, endearing creature.

On his home island, the plants that he and his kind depended on had been nibbled away by goats brought by sailors, while their eggs were eaten by rats that jumped from the ships. The tortoises themselves used to be carried on board to serve as living larders.

Clearly attitudes to the natural world change over time - and vary between regions.

For a poor villager in Africa, poaching an elephant for its tusks is easy money. For people in China, ivory and rhino horn are important culturally and - wrongly - medicinally.

Conservation is a fairly new idea - ivory used to be a major staple of British Empire trading.

By contrast, I found the sight of a haul of smuggled tusks in Bangkok Airport profoundly depressing. The stench was intense and a customs officer said the ivory "smelled like death".

So what are the arguments for resisting extinction? One is purely selfish - economics.

For example, if we fish every last tuna, thousands of people in the fishing industry will lose their jobs. Likewise, if every lion or elephant is shot, the tourist trade will suffer. Extinction can cost in hard cash.

Furthermore, there may be unintended effects from eliminating "keystone" species - the loss of one plant or creature in a food chain may affect a whole web that we depend on in some way that we have not yet understood.

In Thailand, I heard that too few tigers could mean too many deer. In turn, that would mean more destruction of vegetation with a knock-on impact on the birds and monkeys that live in the trees.

Another argument is moral - that as the most powerful species on the planet, we have an obligation not to obliterate others, especially if it is through wanton carelessness.

In other words, a mark of civilisation would be to feel responsibility for the survival of weaker species.

A final point that I find compelling is that we are the first species to have gained the remarkable knowledge that every living thing has its DNA at its heart. We all share that.

We may not like everything - ants, spiders, slugs and snakes - but we are related to them. In an extremely loose sense, they are family. And that casts the threat of extinction - and our role in it - in a very different light.

David Shukman's report What's wrong with extinction? will be broadcast in a new programme, BBC News: The Editors, starting on BBC1 on 25 March at 23:15 GMT.

A measure of the distance travelled is that it takes a staggering 16 hours for Voyager 1's radio messages to arrive on Earth.

Standing in Nasa's Jet Propulsion Laboratory in California two years ago, I watched as data from the lonely craft flickered across giant screens.

The scientist behind the mission, Ed Stone, talked in adoring terms of the 70s technology that has survived decades of hurtling through space to become mankind's most distant emissary.

Nasa has speculated for years about the actual moment of crossing from our Solar System into the void; and now this may finally have happened.

The next time the craft will come even remotely close to another star? About 40,000 years.

UK Seabed Resources is a subsidiary of the British arm of Lockheed Martin.

It has plans for a major prospecting operation in the Pacific.

The company says surveys have revealed huge numbers of so-called nodules - small lumps of rock rich in valuable metals - lying on the ocean floor south of Hawaii and west of Mexico.

The exact value of these resources is impossible to calculate reliably, but a leading UN official described the scale of mineral deposits in the world's oceans as "staggering" with "several hundred years' worth of cobalt and nickel".

An expedition to assess the potential environmental impact of extracting the nodules will be launched this summer amid concerns that massive "vacuuming" operations to harvest the nodules might cause lasting damage to ecosystems.

With the support of the British government, UK Seabed Resources has secured a licence from the United Nations to explore an area of seabed twice the size of Wales and 4,000m deep.

Under the UN's Convention on the Law of the Sea, mining rights on the ocean floor are controlled by a little-known body, the International Seabed Authority, which since 2001 has issued 13 licences - with another six in prospect.

These licences, valid for 15 years, have been bought for $500,000 each by government organisations, state-owned corporations and private companies from countries including China, India, Russia, Japan and South Korea.

The high prices fetched for copper, gold and rare-earth minerals are leading to a surge in interest in mining the ocean floor. The idea first surfaced in the 1970s but was dropped because the costs were too high and the technology could not cope.

The nodules are known to contain up to 28% metal - 10 times the proportion found on land.

A similarly high metal content is found in another target for seabed mining: hydrothermal vents, chimneys formed by extremely hot water, rich in minerals. We reported on the discovery of the world's deepest vents last month.

Stephen Ball, chief executive officer of Lockheed Martin UK, owner of UK Seabed Resources, says the engineering experience of offshore oil and gas operations and the trend to rising mineral prices have now combined to make seabed mining feasible.

"It's another source of minerals - there's a shortage and there's difficulty getting access, so there's strategic value for the UK government in getting an opportunity to get these minerals," he told the BBC.

China's domination of the global production of rare-earth minerals in particular has fuelled the search for other sources of materials essential for everything from electronics to wind turbines.

But many marine scientists and conservationists have warned that the implications of this deep-sea gold rush are not yet understood - and that mining nodules or hydrothermal vents could prove catastrophic for seabed ecology.

Mr Ball said exploration over the next three years would establish whether a system to vacuum up the nodules could be designed to cause minimal impact. The nodules typically lie in a shallow layer of silt.

He said he believed it would be "perfectly feasible to create a benign method to extract these minerals from extreme depths without disturbing the seabed."

"But until we've demonstrated that, there will be a debate around that."

One risk is that the mining operations could generate huge plumes of sediment that could drift through the sea - choking any marine life that feeds by ingesting water and filtering out its food sources.

Michael Lodge, general counsel for the International Seabed Authority, told me that the authority's aim was to encourage a new mining industry to exploit seabed minerals but within strict environmental controls.

"The nodules are generally lying in sediment that is between 2-6in (5-15cm) thick that's been there undisturbed for millions of years. We simply don't know the recovery times or the distribution of species - there are lots of uncertainties."

He described mining hydrothermal vents as "more invasive" because it would involve breaking up the uppermost metre of the sea floor and piping the rock fragments to the surface.

A Canadian company, Nautilus Minerals, is hoping to be the pioneer of vent mining with plans for operations off the coast of Papua New Guinea. However, work is currently delayed because of a legal dispute. The concern is for the impact mining could have on ecosystems

Nautilus would use massive robotic machines, which are being built in Wallsend, near Newcastle-upon-Tyne, by a firm with long experience of marine engineering, Soil Machine Dynamics.

Nautilus says that it is devising strategies for minimising the environmental impact, by trying to contain any disturbed sediment and leaving parts of the seabed untouched so the mined area can be recolonised by marine life.

A leading biologist, Professor Cindy Van Dover of Duke University in North Carolina, has carried out research for Nautilus and says life might recover after a single mining event but that no-one can be sure.

"How do we do this so a hundred years from now somebody doesn't look back at us - at me - and say 'Oh my God, I can't believe they were so stupid and let this happen in a particular way'.

"So how do we do it right? How do we do it sustainably?

Michael Lodge has also said questions will remain about profitability while the final terms of mining licences are settled.

The authority was set up to encourage and manage this new sector but any future business, such as the Lockheed Martin subsidiary UK Seabed Resources, will have to pay royalties to the authority to be distributed to developing countries. The exact details have still to be negotiated.

Research into seabed minerals has a long and slightly conspiratorial history, starting in the Cold War with the United States and the Soviet Union surveying the oceans ahead of possible future conflict.

Surveys of seabed nodules in 1970s were also used as a cover by the US for the secret retrieval of a lost Soviet submarine.

Now, the legacy of all that research and exploration is the growing likelihood of large-scale mining operations, fuelled by rising mineral prices, in many parts of the ocean in the coming decades.

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Now back on dry land after broadcasting on the latest work on the research ship James Cook in the Cayman Trough, I'm still picking up messages from people amazed at getting such an extraordinary vision of the reality of the deep sea.

Technology is transforming the way in which we can view our planet. The star of the show is ISIS, the remotely-operated vehicle equipped with HD cameras despatched as an emissary into the unlit depths.

With remarkable accuracy, the pilots on the James Cook used an acoustic navigation system to "fly" the robot over the rock three miles (4.8km) down towards the oases of life thriving around the vents.

The clarity of the images was astonishing - laying bare everything from the spindly grey-brown chimneys, rising at crooked angles, to the violent pitch-black jets of superheated water to the ghostly swarms of blind shrimp.

It's often said that we know more about the surface of the Moon or even of Mars than we do about the two-thirds of our planet covered by water.

Slowly that's changing, but rather like a torch beam picking out features in a darkened cave. Satellites give us a broad overview of the ocean floor, ISIS and other robots give us the detail.

I write this from Grand Cayman waiting for my flight home. The sea is flat and gives no clue about what lies below.

The UK scientists and crew of the James Cook are deploying the ISIS again right now. Its cameras spotted an oceanic white-tip shark during the descent.

This is a mission of genuine exploration. Who knows what they'll find next?

A huge surge of water swept down the North Sea on 31 January 1953, pulverising the east and south-east coasts of England in an onslaught with powerful echoes even now.

That national trauma 60 years ago - one of the worst peacetime disasters in British history - still guides research into the dangers of coastal flooding and the efforts to manage defences against it.

Back then the shoreline was largely undefended with few barriers to hold back the exceptionally high waters. Only central London, guarded from the Thames by a series of embankments, had any serious protection.

The Met Office was in operation, but it had no system for forecasting the coincidence of weather, waves and tides that would give the sea such overwhelming force.

Even as towns and villages and farms were hit, one after another, the various authorities lacked any kind of coordination so no information was passed on or warnings given.

As the people of Lincolnshire and East Anglia were coping with the shock and misery of lost lives and devastated homes, households further south - in the Thames Estuary - went to bed with no clue that the deadly waters were heading their way.

The final death toll of 307 led to an entirely new perception of the risk the sea could pose to an island nation. The distinctively shiny shapes of the Thames Barrier are the most tangible result.

Storm surges have the potential to be dangerous because they involve a great upwelling of a stretch of ocean - intense low pressure at the heart of a storm literally tugs the sea surface above its normal level to create a massive bulge. In 1953 this stood several metres high.

The surge then acts as an elevated platform on which the winds of the storm whip up waves that can be reach much higher than usual. If this coincides with a high tide, the risk can become extreme.

Geography provides an exacerbating factor: where the North Sea narrows into the English Channel, the waters are funnelled towards the English and Dutch coasts. In the Netherlands, where large areas are below sea level, the 1953 surge killed more than 1,700 people.

While the flash floods caused by intense rain tend to be localised and flooding from rivers usually comes with plenty of warning, coastal inundations can be far-reaching and violent. As one government emergency planner once told me, "it's storm surges that really worry me."

So what lessons have been learned? Most significantly, forecasting has improved beyond all recognition. The 1953 storm struck before the space age. Satellites now keep watch on the weather systems and computer models calculate whether the conditions are right to create a surge.

A network of monitoring stations around the coast provides minute-by-minute data on the height of the sea. And the Met Office, Environment Agency and other bodies not only talk to each other but also work together on a system of warnings. The emergency services and local authorities are involved in preparations.

The 1953 produced a massive physical response as well: beyond the Thames Barrier, a network of hundreds of miles of sea walls now stands against a rising sea.

With budgets tight or declining, only London gets the highest standard of defence and winning new or improved protection can be quite a battle for many communities.

But while the coast is immeasurably better guarded than it was 60 years ago, the population living close to it has soared.

More people and more economic value need protecting than ever before. For example Canvey Island, which saw a terrible loss of life in the flood, has three times more people than 60 years ago.

And the shoreline itself has changed. The south-east corner of Britain is gently subsiding while the sea is rising, as it warms, so the relative level of the sea is increasing.

At one stretch of shoreline in Essex, it is now 10cm higher than it was in 1953 - the kind of rise that could make the difference between a flood defence holding or being overwhelmed.

Given the cost of building ever larger sea walls, there is an attempt to harness Nature's own defences. The Dutch call it "making space for water".

Dr Iris Moeller of Cambridge University and her colleagues, study those often-forgotten features of our coastline, the salt marshes. Working on a project known as CBESS funded by the Natural Environment Research Council, they have calculated that waves lose about half of their energy when they pass over just ten metres of marshland.

"Each wave is like a hammer stroke beating on a sea wall which starts to make it crack and then we have to repair it," she says. "But when we have a salt marsh, it takes away the power of those hammer strokes so the wall can be more cheaply made."

If spending on defences remains limited, and the scenarios for sea-level rise through climate change prove correct, conservation of the marshes may acquire more urgency.

So are we safer than in 1953? Definitely, according to the Environment Agency. But its officials find themselves torn between wanting to reassure people that the threat is under control and reminding us all that no defence is perfect.

The man in charge of London's protection, Andy Batchelor told me: "You can never say never - there is always going to be the tide that may overtop or may cause problems. I'm not scaremongering but it's about people needing to be aware."

As we stand in the Thames Barrier control room, computer screens tracking the waves out in the North Sea, I ask him about the value of remembering the catastrophe of 1953.

His reply? "To remind us to guard against complacency."

First the horse's passport tracking its drug history has to be misleading - an illegal act in itself.

Then the horse has to get past the spot checks - relatively easy because not many are carried out.

Finally, the meat has to end up being processed and sold for human use - almost always on the Continent, very little being eaten here.

The numbers involved in this scenario cannot be large since only around 8,000 horses are slaughtered each year.

But checks since 2007 do show bute turning up in small but consistent quantities. And the stuff is best avoided.

A specialist Defra committee says it has "serious adverse effects". Real harm is very unlikely, but the episode once again raises awkward questions about the international meat trade.

Or the country that fostered the Industrial and Agricultural Revolutions could succumb to the all-too-familiar affliction of coming up with astonishing inventions only to see others walk off with the profits.

That's the stark choice of scenarios laid out by the science minister David Willetts in an examination of the potential and pitfalls of British research in the years ahead.

The assessment comes in a pamphlet, Eight Great Technologies, published by the think-tank Policy Exchange.

The technologies were first identified in a speech by the Chancellor George Osborne at the Royal Society and have been selected for their scientific importance, Britain's "distinctive capability" and the chance of commercial opportunities.

In other words, they are all areas in which Britain should not only excel but also benefit from the flourishing of whole new industries and new jobs.

The optimistic scenario involves Britain leading in exciting new realms such as regenerated body tissue and tiny satellites and the handling of 'big data' to improve health care and weather forecasting.

In talking of these advances, Mr Willetts carries the infectious enthusiasm of anyone who has spent time hearing the imaginative visions of inventors and scientists and entrepreneurs.

Ideas include a British-designed car that could "drive you down the M1 in five years' time", the reusable Skylon spaceplane, which we reported on last year, "skipping a generation in launch technologies", and robotic submarines that could travel unmanned for six months at a time under the Arctic ice sheet measuring environmental change.

Britain's unique history of record-keeping - of the weather, of NHS patients and of agricultural research - is also suddenly of modern scientific value. Combined with excellence in software-writing, it should also provide great opportunities for new tools for 'data mining' and new hubs for IT.

But the minister's admiration for British ingenuity is mingled with a barely-concealed dread: that the most promising offerings from the labs might not be turned into commercial products by British companies.

His worry is nothing new. His predecessors and others in the field have long bemoaned the fact that so much British brilliance stumbles into the notorious "valley of death" that must be crossed for a new idea to make it to the market place.

The "valley" is the stage where adventurous investors, including the public sector, are meant to step in to help fund the crucial but risky transition from concept to product.

From the development of the jet engine and liquid crystal displays, from cracking the inner workings of DNA to pioneering work on Lithium-ion batteries, the country has all too often managed to break new scientific ground but then fail to capitalise on the vast potential that others then enjoy.

Only last month we reported that though the 'miracle material' graphene was first isolated in Manchester University, the race to secure patents on it - and thus try to make money from it - is being won by China and the United States.

Even the South Korean electronics giant Samsung has nearly 10 times more graphene patents than the UK as a whole.

Obviously there are some successes. The chip designer ARM grew out of the BBC Acorn computer project. And Manchester University and others will fight back in the graphene patents contest.

But the challenge, Mr Willetts believes, is to overcome a historic legacy of underinvestment - and a lack of policy attention - in the R&D stage that can see ideas successfully cross the perilous valley.

"Strong markets and flexible markets is a good combination. But, like patriotism, it is not enough. It misses out crucial stuff in the middle - real decisions on backing key technologies on their journey from the lab to the marketplace.

"That is the missing third pillar to any successful high-tech strategy…

"It is our historic failure to back this which lies behind the familiar problems of the so-called 'valley of death'."

One striking example came with the Lithium-ion batteries - very successfully exploited by Japan.

"It was the gap between our basic science and the manufacturing techniques which gave the Japanese their chance. We must not repeat that mistake."

So what can be done? Mr Willetts is just back from the sunshine and energy of San Francisco. He was driven in Google's autonomous car, obviously loved it and looks to two crucial differences between the support offered by the British and American governments.

First, US public funding continues for longer in the lifecycle of a new idea to bring it closer to market.

By contrast, Mr Willetts describes the British policy in terms that capture the brutality of the natural world.

"Sometimes our approach can look like mother birds pushing their fledglings out of the nest but with too many falling to the forest floor to be eaten by foxes."

Second, the US government continues its support beyond the research stage through procurement: by placing big orders with small new companies.

"Silicon Valley originally grew on the back of contracts from the military for computers and IT."

One major effort here is made with the Technology Strategy Board, a body that endeavours to combine public and private finance to nurture new technologies.

But beyond that, Mr Willetts is thinking of a "Leadership Council" bringing together ministers, business people, officials and researchers to prepare "road maps" on technologies - to smooth out regulations and foster development.

He looks ahead 10 years to ask whether the "Great Eight Technologies" will still be in the lab or developed abroad; whether they will have spawned new British Googles and Facebooks or attracted multinationals around British research centres.

No single path is certain, he admits. But the good ones involve pushing against the tide of technological history, and that's never easy.

It might be useful to a few applications, he complained, but graphene will never be revolutionary: the technology is too limited - it is interesting but not a game changer.

We were talking a few months after the Chancellor George Osborne had allocated £50m to graphene research.

The year before, Andre Geim and Konstantin Novoselov of Manchester University had won the Nobel Prize for Physics for their pioneering work on the "miracle material" and the funding was a vote of faith in an exciting new area of research. Another £11m followed just after Christmas.

Graphene is the name given to a novel substance composed of a single layer of carbon atoms, extracted from graphite, with astonishing properties: the stuff is stronger than diamond, more conductive than copper and more flexible than rubber.

However amazing, more than £60m is a lot of money to pump into one particular area of science in an age of austerity and researchers in other subjects are always bound to quibble, at the very least.

In the clamour for funding, resentment is not unusual, particularly if the money appears to be aimed at one specific project rather than a whole field of fundamental research which may deliver far more in the long run.

The objection is to what could be called the Concorde syndrome: public money being hosed at a single project, in that case a supersonic passenger plane, admired for its beauty but limited in its possible uses.

But graphene is different and has caught the eye of the British government - and other governments and companies - precisely because its potential benefits reach into an extraordinary range of areas.

Even if it fails to deliver all that is promised for it in, say, electronics, it might still prove incredibly useful in others such as energy or medicine.

In a paper in Nature last year, Professor Novoselov and his colleagues outlined a "road map" for possible applications of graphene, exploring whether it could become "the next disruptive technology, replacing some of the currently used materials and leading to new markets?"

They acknowledge that many of the material's most exciting characteristics are only achieved with the highest-grade graphene and that industrial-scale techniques for making it have yet to be confirmed.

Still, they argue that a long list of applications is plausible.

Flexible electronic screens may emerge soonest, with the most appealing idea being "e-paper". A working prototype is expected by 2015, according to the Nature study, though the costs are still far too high for any marketable product at the moment.

The authors acknowledge that the established role of silicon will mean that graphene, which is not a semi-conductor, might not play a part in processors till after 2021.

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However, they say graphene is so thin that a "paint" could act as a rust protector or an "electronic ink" or be added to advanced composite materials to make them impermeable or conductive or stronger.

It could be used to enhance solar cells and to improve the working life of batteries, though a lot of technological barriers still remain.

As a material highly sensitive to the environment, graphene could act as a sensor with a single device measuring strain, gas, magnetism or pressure.

And its purity and large surface area make it suitable for medical uses too: from aiding drug delivery to building new tissue for regenerative medicine. However, the authors admit that the sheer number of hurdles mean this will not happen before 2030.

They recognize that "established benchmark materials will only be replaced if the properties of graphene, however appealing, can be translated into applications that are sufficiently competitive to justify the cost and disruption of changing…"

In other words, the price and hassle of switching to graphene need to make sense financially.

So, the paper argues, graphene's "full potential will only be realized in novel applications, which are designed specifically with this material in mind…"

What this means is that graphene is something of a gamble: to really make sense, people will have to dream up inventions for it.

The bottom line is that graphene is too good to be ignored and - in some applications - may yet prove to be too good to be true.

But a look at the statistics for patents - a key indicator of commercial intent - reveals how many countries and companies are prepared to throw the graphene dice.

From a standing start with the Manchester work in 2004, there are now more than 7,000 patents on graphene, with the largest number - more than 2000 - held by China. Samsung alone holds more than 400.

Massive investments on this scale can turn sour - plenty of promising technologies do flop.

But the greater the level of finance, energy and sheer brainpower devoted to graphene globally, the greater are the chances of exploiting it successfully.

The miracle material will soak up a lot of money but, taking a long view, it's unlikely that much will be wasted.

The fact is that the science of understanding why rain falls, and where and when, and how it then soaks into the ground or spills into the streets, is extremely challenging.

And Britain, as an island nation, tucked between the Atlantic Ocean and the continental mass of Europe, and caught in a tussle between mild maritime air and icy blasts from the Arctic, has the least predictable weather of all.

So, as the Met Office tells us what we guessed already - that 2012 was one of the top five wettest years on record - a huge effort is under way to improve the forecasting.

This could make the difference between floodwaters that are contained and those that ruin homes and wreck lives.

One initiative is research that involves bands of scientists braving the turbulence of flying through the heart of storms - the only way to measure what is happening inside them. I reported on one of these missions last year.

Further flights are planned this year with a focus on the south west of England where violent downpours have caused devastation in places like Boscastle in 2004.

The rain that battered that Cornish village was far greater than the computer models had forecast so the scientists will try to get a better grasp of the forces at work inside the clouds.

One of the scientists leading the research is Prof Geraint Vaughan, of the University of Manchester, who told me that however good the models "we can't escape the fact that the atmosphere is chaotic".

One option is for weather centres to run 'ensembles' of models with different variables - groups of computer simulations to see if any come up with similar forecasts.

According to Prof Vaughan: "Sometimes the ensembles all look broadly similar (and different models from different weather centres agree) - then a forecast can be made with some confidence.

"At other times the ensembles diverge and confidence is much lower.

"Knowing how to construct and interpret an ensemble is something we still need to do a lot of research into, but in principle it's a big step forward in gauging uncertainty of the weather forecast."

So a really accurate forecast weeks ahead is unlikely - there are just too many different factors involved.

The best hope lies in trying to identify the broader changes under way - for example with the retreat of the Arctic sea-ice or the cycle of warming in the Pacific Ocean with El Nino and La Nina.

Understanding their impact might make it possible to offer some odds on the kind of weather likely in a coming season.

But, as Prof Vaughan admits: "I don't think I'd want to plan my holiday on such a basis!"

So, what about trying to forecast not only the rainstorms but also their likely impact?

One project being planned for release later this year is the first of a series of 'hydrological outlooks' for the UK - forecasts of water conditions for the month ahead.

This is being prepared with data from every rainfall station across the country, together with readings from the UK's 1300 river gauges, plus information about soil moisture.

It involves the Met Office, the Environment Agency and the Centre for Ecology and Hydrology (CEH).

On Thursday I reported from the CEH on the latest findings about how much water has soaked into the ground - and saw a bore-hole used for measuring water levels actually spouting out water because the ground was so saturated.

According to Professor Alan Jenkins, of the CEH at Wallingford in Oxfordshire, the outlook will be "a first attempt to give stakeholders what they've been asking for - a guide to water conditions ahead."

"It obviously comes with huge uncertainties but it's about trying to give advance warning.

"As with all models you've got to ask - are they better than nothing? We won't know till we've tried one in anger."

A key factor that is missing at the moment for any flood forecast is the level of saturation of the soil.

The current estimates are produced by analyzing a range of variables like rainfall, temperature and evaporation.

So scientists are planning a major new research network of moisture indicators - 50-100 devices across the country that would feed real time data on the amount of moisture in the soil.

Similar to a much larger network being rolled out in the US, and Britain's version, known as Cosmos, would cost in the region of £10m.

The rationale is that any flood forecast would be much more accurate if the computer models include not just rainfall and river flow but the level of ground saturation too.

The devices would be so-called cosmic ray moisture probes - small instruments standing about 2m above the ground - which would measure neutron intensity.

Basic physics describes how neutron activity is correlated with the presence of water and each instrument would cover an area of about one square km and down to a depth of about 50 cm.

Prof Jenkins estimates that if the project gets the go-ahead it could improve flood warnings "by several hours".

"Even an additional 2-4 hours of warning can make a big difference - you can get a lot of sandbags out in that time."

None of this will stop the barrage of criticism aimed at the authorities when they get forecasts wrong - but it is the start of the long and painful journey of trying to get it right.

This really matters. The Met Office count of days of extreme rainfall for the past half-century shows a slight increase in the frequency of the heaviest downpours. And warmer air can hold more moisture - which means more rain.

Lives, homes, businesses, travel - there's a lot at stake.

The rest will be gone, along with all the equipment, the stores and a union jack, in a few weeks' time, leaving no trace of this daring mission to reach beneath the ice.

The most exciting science often carries the greatest risk and, despite three years of planning, this is a gamble that has not paid off.

The talk from the team is brave, of course - of lessons learned, of valuable experience, of regrouping to try again.

But the voice of the chief scientist, Prof Martin Siegert, conveys the painful combination of exhaustion and failure that marks all projects that go wrong.

And it carries memories of another brave British attempt to search for life, on another planet almost 10 years ago.

The aim in Antarctica was to use a hot-water drill to reach down through the two miles of the ice sheet to open a borehole to the waters of Lake Ellsworth below.

The plan had estimated that five days of drilling would do the job and would then allow for 24 hours before the hole re-froze to lower devices into the water and sediment.

In theory, by now, the team should have been hauling to the surface precious containers holding samples from a lost and hidden world isolated for up to half a million years.

Instead the hot water drill did not manage to reach into the depths as required.

The drilling plan called for the creation of a large cavity in the ice to act as a reservoir and as a means of regulating the pressure from the lake below.

The cavity was formed - so far, so good - but when the main borehole was drilled, just 1.5m from the hole leading to the cavity, it could not make a connection down below.

The team assumed that the borehole would descend vertically but maybe it veered off slightly which meant that an accurate aim - and connection - was not possible.

And without being able to hook up the main borehole to the cavity, countless gallons of hot water were wasted in the attempt and the limited fuel stores rapidly depleted.

On Christmas Eve, a fateful decision approached. This £8m project had coped with equipment breakdowns and last-minute hurdles, ferocious weather and utter remoteness.

At one stage, an electronic component the size of a thumbnail - essential to the running of the main boiler - had to be flown out all the way from Britain.

But in the end it was the drilling that proved the project's undoing: it simply could not continue because fuel was running low.

By the evening, gathered in the main tent, the team had to face an awful moment: there was no option but to pull the plug.

The chief scientist, and main driver behind the project, Prof Martin Siegert, prepared a few words for on-site cameraman Pete Bucktrout. It was '"Game over".

Last summer, when I first met Prof Siegert, I was too polite to remind him of what had happened to another British science project, the Beagle 2 mission to Mars, the spacecraft named after the ship that had carried Charles Darwin.

That clever piece of engineering was a tiny lander that was carried to the Red Planet in 2003 on board the European Space Agency's Mars Express orbiter.

Back then many of us gathered with Beagle's mastermind, Prof Colin Pillinger, to wait to hear the first signal that the spacecraft had touched down safely. The signal never came; Beagle went missing, presumed dead.

So it was to my surprise that Prof Siegert himself brought up the parallel, comparing that audacious attempt to search for life on Mars with his own bid to seek it in the unlit depths beneath the Antarctic ice sheet.

At the time, in that summer conversation, neither of us realised an eerie coincidence. Beagle crashed on Christmas Day 2003; the Lake Ellsworth mission was abandoned on Christmas Eve 2012.

Over a crackly satellite phone connection today, Prof Siegert managed a laugh at the timing.

But there is a difference between the two projects. Funding was never found to launch another Beagle to Mars while it is likely that another attempt will be made on Lake Ellsworth.

The team will work on a revised plan next year. Another go may be tried in four or five years' time.

For the moment, though, the fundamental question that drove both missions remains unanswered: what is the limit to where life is possible?

The team knew that the risks were high, but the idea of exploring an ancient and mysterious body of water isolated for hundreds of thousands of years had inspired passion and determination.

The challenge of designing and engineering equipment that could remain sterilised on the long journey to Antarctica, and then down through the 3km of ice-sheet, was immense and involved hundreds of people.

So the disappointment will be felt far beyond the 12 men at their remote camp on the ice. Engineers, technicians, support staff - and researchers eager for the results - will feel heavy disappointment. They may try again next year. But this was frontier science, a gamble, and it did not pay off.

The project to drill through the ice-sheet to reach the hidden waters of Lake Ellsworth has been on hold for the past week after a boiler broke down.

The component just arrived after a journey of roughly 15,000km.

Engineers will now attempt to fit the part in the next few days in the hope of restarting drilling next week.

The drill is meant to be powered by hot water but the entire effort had to shut down when a "varistor" - a variable resistor - on the boiler's circuit board burned out. A replacement also failed.

A spare was sent from Britain via Chile to the remote camp in West Antarctica.

But tension surrounding this operation is mounting because of the uncertainty about whether the boiler will not only fire up but also whether it will continue to run for at least a week - or fail again as a result of a fundamental fault.

Another major concern is the amount of fuel being used to run a back-up boiler which is essential for keeping the drill system from freezing up.

It is likely that the system can be kept ticking over in this way for another fortnight - but any longer will use up too much fuel to power the main boiler for the drilling operation itself, assuming it starts.

In case the new component fails, another replacement is already on its way from Britain but is likely to take several more days to reach the drill site.

So the window of opportunity for a successful drilling operation is getting tight.

Should it prove impossible to carry out the drilling before winter arrives in February, one option on the horizon will be to winter-proof as much of the equipment as possible to be ready for another attempt next year.

But sources at the British Antarctic Survey say they are still determined to keep trying and that "fingers are crossed" that the new component will work.

The project's aim is to penetrate the 3km-thick ice-sheet to gather samples of water and sediment from the lake below - to answer the fascinating question of whether life is possible in conditions of total darkness and immense pressure.

Lake Ellsworth is one of nearly 400 sub-glacial lakes in Antarctica - a feature of this polar region only discovered 16 years ago.

If the drilling does start next week, the first samples could be brought to the surface a week later.

The team has reported "a serious problem" with the main boiler used to heat the water that powers a drill.

Work was halted on Saturday in what could prove to be a major blow to the project to investigate sub-glacial Lake Ellsworth.

The aim is to use 90C water to blast a hole through the two-mile-thick ice-sheet to reach the lake waters below.

The research goal is to gather samples of water and sediment to search for signs of life and clues about the region's climatic history.

Prof Martin Siegert, chief scientist of the project, said: "The technical difficulties are something that are not unfamiliar in Antarctica - it's a hostile environment and very difficult to do things smoothly.

"The good news is that we found the fault relatively early on in our deployment system and so we have quite a lot of fuel that is left remaining. If we didn't have that of course we wouldn't be able to continue any further.

The project relies on the successful operation of the hot-water drill which in turn depends on the boiler.

Last Thursday the team reported that a key circuit on the boiler - controlling the primary burner - had failed to start.

A back-up burner was fitted which ran successfully for 4-5 days - enough to melt the water needed to start drilling.

The first task was to melt a cavity 300m below the ice to act as a water store to help balance water pressure once the main drilling to the lake started.

In a statement released this morning, the team announced: "Unfortunately, the burner failed at approximately 3pm local time on Saturday."

A replacement component has been ordered and is expected to reach the team in a few days' time.

"In the meantime," the statement says, "the engineering team is in contact with the manufacturers of the units who are helping them to determine the cause of the malfunction.

"Both units demonstrated the same problem. When the replacement circuit arrives the engineers will work with the manufacturer to go through the set up procedure. The team is hopeful that this will solve the problem."

"If not, a further option is to attempt to bypass the circuit and manually "drive" the burner. The team is discussing operating protocols with the manufacturer before exploring this option further."

Project manager Chris Hill told BBC News in an email that the boiler was currently running on a back-up electric element which is not powerful enough to heat the water to the temperature needed for drilling.

"We are also vulnerable if this element fails, we will have to fully drain down the system…and start over from scratch - this would be a big deal."

A major concern is that the system was designed to be operated on one attempt - to heat the water and melt open the bore-hole without pause to avoid the risk of ice forming inside the drill-pipe.

However sources at the British Antarctic Survey say there is no issue of any water having frozen in the pipes. They say the system is still "ticking over" with warm water.

In temperatures as low as minus 30C, and in a region notorious for its winds and remoteness, any technical problems of this scale are a huge challenge.

Martin Siegert commented: "We're working very hard to make sure things are right here. It's not the end of the field season by any means and with our suppliers in the UK and the expertise we have on site we're hopeful to restart drilling in a few days' time."

The team always recognized that the project involved high risks - with sophisticated technology in a hostile environment.

It is unlikely that the team will resume drilling before Friday 21 December.