Authors: Professor Brian Cox
My grandad, sitting behind me in that 1972 family Christmas photograph, was born in 1900. He was three years old when, on 17 December 1903 at Kill Devil Hills in North Carolina, Orville Wright took the controls of the Wright Flyer and lifted off the ground for twelve seconds. He was 68 when he saw Neil Armstrong walk on the Moon. Orville Wright himself died in the year that Neil Armstrong began studying aeronautical engineering at Purdue University, Indiana. I still find it hard to believe that I have spoken to someone who was born before powered flight, and to someone who walked on the Moon. It is important to notice that this sentence can’t be followed. Someone who walked on the Moon, comma, and someone who … What? Where will the next generation of Apollo’s Children come from? Perhaps a new superpower will take America’s place as the great exploring nation. China and India, those re-emergent cradles of civilisation, have ambitions in space. As Jacob Bronowski wrote in
The Ascent of Man
, ‘Humanity has a right to change its colour.’ But I share his regret that the retreat of Western civilisation may leave Shakespeare and Newton as historical fossils, in the way that Homer and Euclid are. If that is the case, it will be our choice.
Two more astronauts followed Duke and Young onto the lunar surface. They left at 10.55pm GMT on 14 December 1972. Commander Gene Cernan, as he prepared to step on to the ladder of the Lunar Module, quietly spoke the final words from the Moon.
… I’m on the surface; and, as I take
man’s last step from the surface,
back home for some time to come – but
we believe not too long into the future
– I’d like to just say what I believe
history will record. That America’s
challenge of today has forged man’s
destiny of tomorrow.
And, as we leave the Moon at Taurus-
Littrow, we leave as we came and, God
willing, as we shall return, with peace
and hope for all mankind.
Godspeed the crew of Apollo 17.
Gene Cernan, Taurus-Littrow Valley,
14 December, 1972.
Apollo was about many things. It was about winning a race against the Soviets. It was about national pride. It was born out of fear as well as optimism. It was about laying the foundations of American dominance in the late twentieth century. It was about economic stimulus. It was about dreams. It succeeded on all fronts. Was it really about dreams? ‘Well, space is there, and we’re going to climb it, and the Moon and the planets are there, and new hopes for knowledge and peace are there. And, therefore, as we set sail we ask God’s blessing on the most hazardous and dangerous and greatest adventure on which man has ever embarked.’ I think so. Kennedy was a politician, but I believe he meant it.
So what of the dreamers now? Is the twenty-first century the era of pragmatism? The era in which we believe, because we have to, that the interests of shareholders are aligned with the interests of humanity? Innovation funds the shops on New Bond Street, but is that all? A common governmental lament is that new knowledge is not converted efficiently enough into economic growth. Is that what knowledge is for? Who pays for progress? Who
should
pay for progress?
Human Universe
is a piece of documentary television, and this book is based on the series. Television is about stories; examples that illustrate a point.
Human Universe
is also at heart optimistic, because I am optimistic. I think we as a civilisation could do better, as I’m sure you’ve gathered, but it would be ridiculous to suggest that we are not doing some things right. In the final episode, we found two stories that demonstrate that long-term thinking is not dead; one almost Apollo-like in state-funded grandeur, and the other more modest but equally important. The first was a project I’d visited once before, back in 2009, known as the National Ignition Facility at the Lawrence Livermore National Laboratory in California. The aim is to make a star on Earth.
Nuclear fusion is the power source of the stars. The Sun releases energy in its core by turning hydrogen into helium. Two protons approach each other at high speed, because the core is hot. The core became hot initially through the collapse of the gas cloud which formed the Sun. Protons are positively charged, and therefore repel each other through the action of the electromagnetic force, but if they get close enough, the more powerful nuclear forces take over. The weak nuclear force acts to turn the proton into a neutron, with the emission of a positron and an electron neutrino. The proton and neutron then bind together under the action of the strong nuclear force to form a deuterium nucleus, which is an isotope of hydrogen (because it contains a single proton) with a neutron attached. Very quickly, another proton fuses with the deuteron to form helium-3, and finally two helium-3 nuclei stick together to form helium-4, with the emission of the two ‘spare’ protons. The important result in this convoluted process is that four protons end up getting converted into a single helium-4 nucleus, made of two protons and two neutrons, and the helium-4 nucleus is less massive than four free protons. This missing mass is released as energy, in accord with Einstein’s equation E=mc
2
, and this is why the Sun shines. The energy released in fusion reactions is colossal by terrestrial standards. If all the protons in a cubic centimetre of the solar core were to fuse into deuterium, enough energy would be produced to power the average town for a year. Or to put it another way, one kilogram of fusion fuel produces as much energy as 10 million kilograms of fossil fuel, which is approximately a hundred thousand barrels of oil, with no CO
2
emissions; the waste product is helium, which can be used to fill party balloons.
Energy is the foundation of civilisation. Access to energy underpins everything, from public health to prosperity. Access to clean water is surely more fundamental, you might say, but this requires energy. Even in the most arid regions, desalination plants or deep wells can deliver water in abundance
if
sufficient energy is available. It isn’t, of course. Profligate energy use has a bad name today, but consider this. In every country in which the per capita energy use is greater than half the European average, adult life expectancy is greater than 70 years, literacy rates are greater than 90 per cent, infant mortality rates are low and more than one in five of the population is in higher education. The reason energy use has a bad name is not because it is bad in itself. It is good, it is the foundation of modern civilisation, and modern civilisation is a good thing. I don’t want to live on a subsistence farm, sleep in stifling heat, run the risk of dying of malaria and have no access to clean water or cutting-edge medical care. I am lucky. I live in a city, I buy all the food I want from nice shops, I have a fulfilling job in a university and I get to do research at places like CERN, which is interesting. I want everyone in the world to have choices, like I have, and that means I want everyone in the world to have access to energy, like I have. In 2011, 1.3 billion people lacked access to electricity. Yes. Energy use is good. The problem with energy is how we produce it.
The world produces more than 80 per cent of its energy by burning fossil fuels. This is expected to fall to 76 per cent by 2035 as nuclear and renewables grow in importance. Burning things is humanity’s oldest technology. The energy sector is responsible for two-thirds of global greenhouse gas emissions. The most recent scientific modelling suggests that global average temperatures will rise by around 2–2.5°C above the average of the years 1986 to 2005 by 2100. The rise could be less – as low as 1 to 1.5°C, or it could be 4°C or more. Some of the uncertainty depends on our actions, and so there are assumptions about future behaviour built into the predictions. But over 90 per cent of computer models agree that global temperatures will have increased by 2100 as a result of greenhouse gas emissions from fossil fuel burning.
Nuclear fusion, then, is a good idea. If it can be made to work in an economically viable way, it will provide limitless, clean energy for everyone. It is not the
only
way of achieving this goal. One can make a case for solar power, and indeed an increased contribution from other renewables and nuclear fission. But it is a possible way to solve the world’s energy problems for good, in principle, and is therefore worth exploring.
The challenge is technical rather than fundamental, in the sense that we know fusion works because the Sun does it. Fusion is difficult to achieve on Earth primarily because of the colossally high temperatures and pressures required. There are two approaches being followed, and each is Apollo-like. In Europe, a worldwide collaboration involving Russia, USA, the European Union, Japan, China, Korea and India is in the process of constructing ITER. This machine is in effect a magnetic bottle, which can store a plasma at temperatures in excess of 150 million °C – ten times that of the solar core. ITER will use deuterium and tritium, which is another isotope of hydrogen comprising one proton and two neutrons, to make helium-4. This bypasses the slow initial weak interaction in the Sun that makes deuterium out of hydrogen, making ITER a lot more efficient than our star. Deuterium is extracted from seawater, and tritium is made inside the reactor itself by irradiating a lithium blanket with the spare neutrons produced during the fusion reaction. An 800MW fusion power station of this type would consume around 300 grams of tritium fuel per day. ITER is not particularly telegenic at the moment because it is under construction and will not be commissioned until 2019. This is why we chose to focus on the US National Ignition Facility, which is already up and running.
NIF is pure science fiction; in fact, it was used as a set for
Star Trek: Into Darkness
. It is the world’s largest laser system by an order of magnitude. The laser delivers 500,000 gigawatts of power onto a target smaller than a peppercorn in a series of increasingly powerful hammer blows, tuned to arrive with a precision of better than a tenth of a billionth of a second. That is 1000 times the peak energy-generating capacity of the United States. This, as you can imagine, creates a bit of a bang. The peppercorn-sized target contains deuterium-tritium fuel, just like ITER. The laser pulses raise the temperature of the pellet’s gold container, and the X-ray radiation produced drives a rapid collapse of the fuel, initiating fusion. The devil is in the detail; the precise timing and duration of the laser pulses, and the shape of the gold container, all contribute to the chances of success and the efficiency of the process. Despite the tremendous engineering difficulty, in September 2013 more energy was released from a deuterium-tritium fuel pellet than the pellet absorbed, although this was only 1 per cent of the total energy input to the lasers. Nevertheless, this demonstrates that so-called inertial fusion works in principle. The inertial fusion power station of tomorrow would use far more efficient laser systems – NIFs are now more than a decade out of date – and the fuel pellet technology being developed by NIF. The technology has been demonstrated to work, at least on a vast, government-funded research scale, and this is how difficult things like space exploration have to begin. Commercial companies will rarely take such enormous risks, and this means that we, the taxpayers, must pay for the creation of this type of knowledge. As with Apollo, we will be repaid, but the investment horizon is beyond that of the average accountant.
It therefore appears that there is no technical reason why such power stations could not be constructed. There is much research to be done, but the barriers are likely to be budgetary rather than fundamental; the United States spends more on pet grooming than it does on fusion research. There is a serious point behind that cheap shot. I think one of the primary barriers to progress is education. I am a believer in the innate rationality of human beings; given the right education, the right information and the right tuition in how to think about problems, I believe that people will make rational choices. I believe that if I said to someone: ‘Here’s the deal. You can have limitless clean energy for your lifetime, for your children and grandchildren’s lifetimes and beyond, in exchange for grooming your own cat’, then most people would reach for a comb. I have to believe that, otherwise this book is a futile gesture.
The second of our stories couldn’t be more different. It involves no high technology and very little cash, but it may have a tremendous impact. Securing the future isn’t all about money; it’s also about action.
The Svalbard Global Seed Vault is modest and beautiful from the outside. In common with all publicly funded construction projects in Norway, the simple door on an Arctic hillside is a work of art, created by Dyveke Sanne. In the summer, it reflects the eternal Sun. In winter, fibreoptic cables shine in the perpetual night. The doorway leads into a converted coal mine, deep in the permafrost. There are three caverns, each maintained at a temperature of -18°C by a cooling system. The temperature was chosen very precisely; it is the temperature at which seeds metabolise slowly, but do not die. At -18°C, the most hardy seeds remain viable for over 20,000 years. Only one of the caverns is in use; the other two are for the future. Inside, there are over 800,000 populations of seeds from almost every country in the world. All the seeds are agricultural crop varieties – the raw material for and the foundation of global food production. Seeds from America and Europe nestle next to those from Asia and Africa. Syrian seeds, rescued from the recent troubles in Aleppo, the home of a local seed bank, sit beside those from North Korea, South Korea, China, Canada, Nigeria, Kenya, and so on around the world. The vault contains virtually the whole history of human agriculture, stretching back to its origins in the Fertile Crescent all those years ago. Each seed population reflects some choices that were made, some environmental challenge or perhaps simply the taste of a farmer or his village. There are varieties manipulated by multinationals, or carefully cultivated and cherished by isolated tribes. The boxes are food for the imagination, time capsules, the stuff of dreams. They are also of fundamental importance.