If you’re old enough, you might just remember where you were when the history of human spaceflight began – that seminal moment in 1638 when Domingo Gonsales, a diminutive Spanish adventurer, left the island of Tenerife and flew to the ‘Moone’, in English Bishop Francis Godwin’s ‘picaresque’ tale of space travel, The Man in the Moone. Gonsales made his lunar voyage not on a rocket, but by harnessing a flock of a special breed of migrating lunar geese called Gansa, that pulled him across the circumlunar space between the earth and the moon in some twelve days. Equipped with a religious certainty and a new scientific questioning, he lived for many months with the native Lunars, before heading back to earth. The tale is a reflection on the practicalities of space travel, extraterrestrial life, the universality of Christianity and the exotic new science ideas of the day: planetary science and orbital mechanics, and early ideas about gravity and electromagnetism. It’s a sort of Jacobean James and the Giant Peach and essential background research for anyone wanting to leave the planet. Perhaps we can call Domingo Gonsales our first proto-astronaut? A ‘celestial Don Quixote’? A missionary Buck Rogers?
Godwin wasn’t alone. The French writer Cyrano de Bergerac also imagined A Voyage to the Moon in 1657, propelled to the heavens not by goose power, but by an altogether different scientific phenomenon – the evaporation of dew. Reasoning that the dew on the ground was attracted by the sun’s rays, he bottled it up, strapped the bottles around his body, creating a sort of Jacobean jet pack, rising high above the clouds, but a few broken bottles meant his weight finally brought him back to earth.
In the same year that Francis Godwin’s lunar geese story was published, John Wilkins, a founding member of the Royal Society, wrote his own altogether more practical thoughts on lunar travel in The Discovery of a World in the Moone. The book’s cover illustration shows the sun being orbited by the earth and moon, an advert for Copernicanism. Like Godwin’s adventure, behind the story was a popularization of the new science du jour. Above all, Wilkins was fascinated by the practicalities of the mechanical world, writing about catapults and levers, springs and gears in his later work Mathematical Magick (1648), as was David Russen in his all but forgotten Iter Lunare (1703) which entertained the idea of getting to the moon by using a giant, powerful spring.
These lunar imaginings didn’t spring from the ether. The seventeenth century, much like the second half of the twentieth century, was an important period for ‘Moone shots’. It was the time where our understanding of the universe and our place in it were slowly being turned inside out. The classical world of Ptolemy and Aristotle was giving way to ideas grounded in new technology, exploration, empire-building, art and a European scientific revolution, underpinned by our most important invention of all – the scientific method.
THE RENAISSANCE RIGHT STUFF
In the fifteenth and sixteenth centuries, the world had been gradually mapped by the great voyages of Columbus, Magellan, Drake and Da Gama. Their sailing ships had pushed beyond the horizons, revealing the planet as it was rather than how it had been imagined. Europe was no longer the centre of the universe. Indigenous people, speaking in strange tongues, worshipping blasphemous gods, were discovered, often with disastrous results. Commerce and trade routes were being established, providing a new motivation to explore.
Similarly, the radical new invention called the telescope permitted us for the first time to reveal the celestial bodies, not as imagined supernatural manifestations, but as viable destinations. Solid islands floating in the ocean of space. Galileo Galilei, looking to the heavens with his new configuration of lenses, confirmed the Copernican model of the solar system as heliocentric rather than geocentric, not just in theory but in testable practice. For the first time the moon’s surface was revealed. Planets and their moons were drawn. Sunspots were seen moving across the face of the sun. The architects of this revolution in thinking – Tycho Brahe, Robert Boyle, Francis Bacon, Johannes Kepler, Robert Hooke, John Wilkins, and later Isaac Newton – were studying God’s intricate handiwork in detail. Gravity, magnetism, astronomy and anatomy were all under the spotlight.
In the seventeenth century, this new knowledge seeded the imagination of the scientists themselves. In 1608, physicist Johannes Kepler, famous for his work describing the orbits of the planets, imagined in his novel Somnium what the earth would look like from the moon. He describes the logistics of a moon journey propelled by supernatural ‘daemons’, with a detailed description of the physiological challenges of space travel to humans. Like Arthur Dent and Ford Prefect’s ten pints of beer taken as ‘muscle relaxants’ in the pub before their ride on the Vogon ship in The Hitchhiker’s Guide to the Galaxy, Kepler’s astronauts are prescribed drugs and opium for their space voyage to combat the physical shock. Lack of air and cold were to be remedied by cold sponges up the nose.
What kind of people would Kepler sign up as space travellers? Here are his thoughts so you can see how you measure up:
We do not admit desk-bound humans into these ranks, nor the fat, nor the foppish. But we choose those who regularly spend their time hunting with swift horses, or those who voyage in ships to the Indies, and are accustomed to living on hard bread, garlic, dried fish and other abhorrent foods. The best adapted for the journey are dried-out old women, since from youth they are accustomed to riding goats at night, or pitchforks, or travelling the wide expanses of the earth in worn-out clothes. There are none in Germany who are suitable, but the dry bodies of Spaniards are not rejected.
My subject is, then, what I have neither seen, experienced, nor been told, what neither exists nor could conceivably do so. I humbly solicit my readers’ incredulity. Lucian of Samosata, True History
As long as humans have imagined anything, we’ve imagined going into space. As a literary genre, we can date space travel science fiction to long before the Renaissance, all the way back to True History, by Lucian of Samosata (AD120–c.180), which begins an entire literary genre loosely called ‘imaginary voyages’. True History was a second century proto-Star Wars saga, with sailing ships propelled into space by violent storms, battles between warring factions and nightmarish Hieronymus Bosch-esque descriptions of alien worlds: the moon was populated by a race of hairless homosexuals, who copulated with each other via openings above the calf muscle. The resulting leg growth was then lanced, the child pulled out, and with mouth open to the wind the life force would blow into them.
Lucian, like Jonathan Swift* in his fantasy travelogue Gulliver’s Travels, played with the idea of fact and fiction, weaving fantasy and political satire against a celestial backdrop. The universe was no longer distant and immutable, but a place of revelation. A stage where dramas could play out. Disappointingly, like Star Wars, Lucian finished with a rather lazy ‘To be continued…’. Unlike George Lucas, he never got round to the sequels.
With all science fiction, whether first century, seventeenth century or twenty-fifth, dream worlds and real worlds orbit, collide and cross-pollinate with what we know to be true and what we imagine may become. It’s our incomplete knowledge that gives rise to the wildest reaches of the imagination. Imaginative flights of fancy are still our most powerful form of transportation, beyond anything we could engineer.
But of course nothing will ever happen in the real world unless you imagine it first. John Wilkins at least offers some practical advice to the would-be space traveller in his treatise Mathematical Magick for those attempting to defy ‘gravitas’:
* By the help of fowls
* By wings fastened immediately to the body
* By a flying chariot.
The first three options are problematic. Option four – the flying chariot – has provided the more successful basis for modern space travel.
But where will such a machine take us? Where is space exactly?
For me space begins near junction 15 of the M6, in between Ashbourne and Leek. I’m at Alton Towers theme park, with Al Worden, the charmingly funny Apollo 15 Command Module pilot, who flew to the moon and back in 1971, earning himself the title of ‘world’s most isolated human’ as a result. Al had remained alone in lunar orbit while the two other crew members were exploring the lunar surface. We’re here doing some interviews for World Space Week, as well as being guests of honour for the opening of the park’s latest space-themed virtual reality roller coaster, Galactica. During the interviews, Al held court with a group of local schoolkids, recounting his extraordinary lunar adventure. There wasn’t a flicker of resentment from him, despite having answered the same questions for the last half century: What’s it like on lift off? How do you know which way to go? How do you go to the loo in space?
As dusk fell, we made our way to the roller coaster for the grand opening and duly christened the new ride. Al, with his NASA flight jacket on, and I were manhandled into the front-row seats of an empty rollercoaster. Restraining bars tightened. Walkie-talkies crackled. Final checks were carried out and we prepared for launch. Fifty years ago, he, along with Commander Dave Scott and Lunar Module pilot Jim Irwin, had been through a very similar procedure in a machine that had orders of magnitude less computing power behind it than the one we were now strapped into. The latest in virtual reality headsets were lowered over our faces like the Apollo spacesuit helmet visors, thrusting us into a computer-generated dream state. The laws of physics, engineering and computer science, woven together with our most profound fantasies. As we rattled on our way, the film in front of our eyes immersed us in a future vision (slightly pixellated) of space travel. Like the mighty Saturn V rocket, designed by Wernher von Braun, the roller coaster car climbed the arduous gravity well, until we reached the top. All that potential energy was now released as we dropped down the other side in free fall. I’m weightless for a moment, looking at the spherical earth against the blackness of space. A virtual ‘overview effect’. Leaving the planet is much easier, safer and cheaper when it’s just your imagination that has to do the work. And for that it helps to be on a VR roller coaster at Alton Towers, while sitting next to an Apollo astronaut.
The good news for you, wherever you are in the world, is that space isn’t very far away. A hundred kilometres to be exact. An easy commute in a straight line. That’s the distance from where I’m sitting now (Rosebery Avenue in London) to Portsmouth on the south coast or Northampton. A lot closer than Alton Towers.* A little past Oxford or Cambridge. A train ticket to Portsmouth will cost me £10 and take an hour or so. Seven hours on my bike, according to Google Maps.
There is no physical boundary or natural shoreline marking where space begins, just a gradual thinning of the atmosphere as the air molecules become spaced further apart. The Fédération Aéronautique Internationale (FAI) based in Lausanne, Switzerland, is the official governing body that acknowledges and mediates aerospace records, including human space flight. They are the organization who patrol this imaginary boundary and it is them you will need to convince that you’ve left the planet and entered space.
There was controversy surrounding Yuri Gagarin’s first flight, because officials submitting the documentation of the event had not mentioned that on his return to earth he’d ejected from his spacecraft (Vostok 1) at 20,000 feet. The FAI had stipulated at the time that you had to land with your spacecraft for the record to stand, but – reflecting the spirit of the law rather than the letter – sensibly, in light of the historic achievement of Gagarin’s flight, this rule was amended.
The Kármán Line is an imaginary line 100 kilometres above sea level named after the Hungarian physicist and aerospace engineer Theodore von Kármán. In an informal set of discussions in the mid-1950s with scientists and engineers from the FAI and the, confusingly for us, IAF (International Astronautical Federation), von Kármán established the demarcation line between aeronautics (‘sailing the air’) in the atmosphere, where aircraft need aerodynamic forces to work, and astronautics (‘sailing through the stars’) beyond the atmosphere, where aerodynamic flight is no longer feasible.
As the space race heated up in the early 1960s, aircraft such as the hypersonic rocket-powered X-15 began blurring the line between aircraft and spacecraft, so an official space boundary became important. But this demarcation had international differences at the time. A handful of X-15 pilots, including Bill Dana, John B. McKay and Joseph A. Walker, were awarded ‘astronaut wings’ for 50-mile (80-km) flights. Von Kármán had very sensibly suggested 100 kilometres to be the internationally-recognized boundary line, being a nice round number and easy to remember, and that eventually stuck. Crossing that line now means you get your astronaut wings, which is ironic since the last thing that will help you in space is wings, but excitingly it also means a badge and/or lapel pin along with bragging rights. Who you are and where you’re from will determine what kind of badge you’ll get. Unless you’re a member of the US armed forces, or flying as a NASA civilian, you’d most likely be going for a Federal Aviation Administration (FAA) civilian astronaut badge.
So far, only SpaceShipOne test pilots Mike Melvill and Brian Binnie have this civilian astronaut badge, so you’d be in exclusive company. If you’re planning on becoming a ‘Bransonaut’ with Virgin Galactic they have designed their own pin. If you’re British born, the British Interplanetary Society will award you one of their silver rocket pins with a Union Jack. Private astronaut Richard Garriott lost his and asked for another one. I had the honour of awarding this replacement to him over a pint with some friends in the Cittie of Yorke pub in London’s High Holborn.
GRAVITY WELLS
If space is so close, within walking distance, why is going ‘uphill’ so tricky? In a word: gravity.
Isaac Newton first described mathematically in his work Philosophiae Naturalis Principia Mathematica why your ballpoint pen won’t write upside down and how objects like apples falling toward the centre of the earth are ruled by the same force keeping the planetary bodies in orbit. Gravity, of course, keeps us planted on the ground, keeps the tides moving (thanks to the moon) and keeps the atmosphere in place. All very useful until you want to go somewhere else. We tend to think of gravity as being very strong, holding large structures like solar systems and galaxies together. But the fact that you, weighing 70 kg or thereabouts, can jump in the air under your own muscle power and separate yourself from something as massive as a planet weighing 5.9721986 x 1024 kg, means the opposite is true. Giant stars may collapse under gravity, but a cheap airport-bought novelty magnet sticks happily to the fridge door despite the mass of the entire earth trying to dislodge it. This is all summed up neatly for you in Newton’s famous gravity equation:
I’m momentarily free from the effect of gravity on the apexes of the Alton Towers roller coaster with Al Worden, for exactly the same reason that astronauts float about on the International Space Station. Tim Peake is floating, not because there’s an absence of gravity, but because he’s constantly falling around the earth. If he wasn’t moving, he’d be walking around normally.
BREAKING FREE
The secret to getting into orbit and staying there is to travel fast enough, and not to slow down. Around 17,000 mph will do it. The secret to breaking free of the earth altogether, is to go even faster: say 25,000 mph. We call this earth’s escape velocity.
Let’s say you throw a tennis ball or an apple as hard as you can – how strong you are will determine how fast, and therefore how far, it will travel. You’ll notice as its speed drops, the path of the ball curves (a parabola) towards the ground due to objects – planets and tennis balls – being attracted to each other by gravity. Because the earth is curved,* if you can throw the ball fast enough, say at over 17,000 mph, its curved path is big enough to miss the earth altogether and go on missing it. If your parabola matches the curve of the earth, it will keep falling round and round the planet. A satellite or space station will stay on its trajectory around the earth as long as you want it to because there’s nothing to slow it down, like air resistance.
The smaller your planet, the less gravity there is and therefore the easier it is to leave. Getting off the moon takes a lot less energy than getting out of the deeper gravity well of the earth. Even more massive objects, like stars or giant planets, have even deeper gravity wells. Black holes, which aren’t holes at all but extremely dense collapsed neutron stars, are the deepest of them all.
The key to thinking about gravity and orbits and getting to and from the moon is in the word falling. The moon is falling around the earth. As is the International Space Station (ISS). If the ISS slowed down by firing its rocket boosters in the opposite direction of travel, it would slow down and fall back to earth just like your tennis ball.
At the time of the Jacobean space programme, our understanding of gravity was still in a muddle. It was reasonably assumed that heavier objects, when dropped, accelerate to the ground faster than lighter ones. Galileo Galilei in 1589 famously (apocryphally) dropped two different weights off the Leaning Tower of Pisa to show that in fact they fall at the same speed. You can try this: if you drop, say, a hammer and a feather then it seems reasonable to assume that the hammer will hit the ground first. You’d be right, but only because of their shapes – air resistance slows the feather more. If you go to the moon (where there is no air), and specifically to the Apennine mountain range at the Apollo 15 landing site, you will see a geological hammer and a falcon feather lying in the lunar dust. If you pick them up, hold them at arm’s length and drop them, you’ll notice they indeed land at the same time, which was confirmed by Commander Dave Scott when the experiment was filmed on the moon in 1971: ‘How about that? Mr Galileo was correct in his findings…’
It wasn’t until Newton’s description of gravity in Principia in 1687 that the basics were cleared up. Isaac Newton in your flying chariot’s driving seat will get you into orbit and to the moon and back. Albert Einstein went even further in describing what gravity actually was and how it worked. In his theory of general relativity* he realized that massive objects like stars and planets warp the fabric of space-time itself, like bowling balls on stretched rubber sheets.
You can demonstrate the time-warping effect of the planet’s gravity field yourself, which I did once on the BBC science programme Bang Goes the Theory. All you need are a couple of synchronized, highly accurate caesium beam atomic clocks, a long-range aircraft and a pilot to fly you and one of the clocks around the world. When you reunite the clocks, you’ll notice they’re no longer synchronized.** A fun experiment to try, although atomic clocks and airliners are generally harder to get hold of than hammers and feathers.
* Title from Professor Allan Chapman. See the end notes section for information on sources and other thoughts.
* The great-great-nephew of Francis Godwin.
* 203 km as the goose flies.
* Due to gravity. If the radius of an object is greater than the so-called ‘potato radius’ of about 200 km, there will be sufficient gravity pulling towards its centre to shape it into a sphere.
** See Hafele-Keating experiment, 1971.
