The following text, by Stephen Ashworth FBIS, has been presented at the British Interplanetary Society’s “Ways to Mars” symposium, held on 19 November 2008 at the Society’s London headquarters. Its main points:
– Most of the mass needed for an Earth-Mars transport system consists of propellants and life support materials, and that is already in space, and already in orbits very close to the ones which we need;
– But this near-Earth asteroidal resource is completely invisible to the space agency paradigm of space exploration, because [the paradigm] excludes the construction of permanent human activity in space.
Transport for Areopolis Or: “Implications of the Choice of Economic Paradigm for Strategies of Manned Access to the Moon and Mars” by Stephen Ashworth
When considering human access to Mars, it seems to me that there are two key points which need to be taken into account, but which are often ignored. I shall offer you these two points very shortly.
Designs for manned missions to Mars typically involve assembling in low Earth orbit a spaceship weighing several hundred to over a thousand tonnes.
For example, each Troy spacecraft, which we shall be hearing more about this afternoon, weighs nearly 800 tonnes to carry 6 astronauts. The “space lego” nuclear powered Mars mission uses two ships of 240 tonnes each, thus a total of 480 tonnes in low Earth orbit. [I was wrong — this turns out to come to a total of 955 tonnes.] The “magic” Mars mission requires five Energiya launches, thus probably weighs 4 to 500 tonnes when ready to go.
Meanwhile the official European Space Agency design study for a Mars mission proposed a ship, again for 6 astronauts, which required 20 Energiya launches for every single Mars departure. These launches would build up a ship weighing 1357 tonnes at departure.
The Mars ship in low Earth orbit thus weighs between about 50 tonnes and about 200 tonnes per astronaut on board. Launching such large masses into orbit for the benefit of so few people is one reason why manned Mars exploration is hopelessly uneconomic.
At present-day cargo rates to low Earth orbit of $10 million per tonne, this is a billion dollars per astronaut, plus the cost of the Mars hardware itself. Even at spaceplane rates, which may fall to as low as $10 thousand per tonne, this is still a million dollars per astronaut, plus the cost of the hardware.
At these rates, there will not be many people going to Mars.
Let me show you an Earth-Mars transfer orbit.
Here is an orbit which reaches out from Earth to pass the orbit of Mars. It has about the same size and shape as the orbit of an Earth-Mars cycler, such as the ones being studied by Buzz Aldrin and his collaborators.
It might therefore be the orbit of a future manned Mars vehicle. But that’s not what I drew. What I’m showing you here is the orbit of minor planet 4660 Nereus.
The concept of an interplanetary cycler, which repeatedly encounters Earth and Mars, goes back to the early 1980s. Alan Friedlander and John Niehoff first proposed setting up long-lived space habitats which remain permanently in interplanetary space. These would periodically be used for transporting people between Earth and Mars. Relatively small ferry spacecraft would complete the transport chain between the cycler and a local parking orbit or planetary surface.
In 1985 Buzz Aldrin added the concept of a gravity assist at each planetary flyby. This technique allows a cycler to stay in phase with the relative motion of Earth and Mars. It enables it to offer passage between these planets once every 2.14 years, the Earth-Mars synodic period.
A great number of near-Earth asteroids, such as 4660 Nereus, resemble natural Earth-Mars cyclers. A proportion of them are believed to be carbonaceous chondrites, containing water and other volatiles. Water in space is of incalculable value as a feedstock for propellant manufacture, as a near ideal substance for radiation shielding, and for other life support functions.
I have checked the online listings of near-Earth asteroids published by the Minor Planet Center. Applying quite stringent orbital criteria, I found a total of 56 Amor and Apollo asteroids which behave like natural Earth-Mars cyclers. New ones are being discovered all the time — for example, of those 56, ten were only identified this year.
Now to my two key points.
Firstly: most of the mass needed for an Earth-Mars transport system consists of propellants and life support materials. That mass is already in space, and already in orbits very close to the ones which we will need to reach and return from Mars. It does not need to be launched from Earth. It can be mined in situ.
So why is hardly anybody getting excited about this? Why does it not form the basis of the Constellation programme, or of the recent ESA or Russian design studies, or even the magic, the trojan or the space lego Mars missions?
Because of my second point: the asteroidal resource is completely invisible to the space agency paradigm of space exploration. That mode of planning excludes the possibility of systematic use of natural in-space materials, and it excludes the construction of permanent infrastructure on Earth-Mars cycler orbits. It will not contemplate anything that suggests permanent human activity in space.
I think we can identify two broadly contrasting attitudes to transport infrastructure.
The heroic paradigm is only interested in special missions of heroic exploration. This is the space agency mode of thinking. Its prime goal is national presige, under a fig-leaf of science, spinoff and educational inspiration. Think of the Apollo programme. Further back in history, think of Zheng He’s epic voyage of exploration around 1421, from a China which was about to close in on itself.
In contrast with the heroic paradigm, we can identify the systemic paradigm of transport infrastructure. The prime goals here are permanence, growth, and economic profitability. Think of the Cunard and White Star steamers which connected Britain with the Americas and the Empire from the mid-nineteenth to the mid-twentieth century.
Now obviously, since there is currently nobody on the Moon or Mars, the next people to travel there will of necessity be heroic government explorers. But the question we need to address is this: will their transport system be designed for cancellation, like Apollo, or will it be designed for growth, like Cunard?
What would a systemic manned space transport system look like?
I have identified four key features.
Firstly, it will employ reusable spacecraft — an obvious enough point.
Secondly, it will not be content with a single route — say, between Kennedy spaceport on Earth and a single base at Utopia Planitia on Mars. It will rather seek to foster a network of different routes among a number of different transport nodes. Those nodes may include an increasing number of space hotels, factories and laboratories, and lunar and martian bases.
Note particularly that the use of transport nodes allows in-space refuelling. This capability was regarded by early spaceflight theorists such as Hermann Oberth and Guido von Pirquet as essential if lunar and martian flights were to become achievable using chemical fuels.
Thirdly, a systemic space transport system will diversity its sources of propellants and life support materials, exploiting the transport nodes for in-space refuelling.
Fourthly, it will not be content with a pillar architecture, but will develop a pyramidal one. In a pillar architecture, one unique space station is succeeded by one unique Moon base, and that in turn by one unique Mars base. In a pyramid architecture, by contrast, it is growth in the use of space stations that supports the first Moon base, and growth in the use of Moon bases that supports the first Mars base.
Thus in impressionistic figures, if there are ten people on Mars, then we should expect to see at the same time at least a hundred people on the Moon, and at least a thousand on board stations in Earth orbit at any one time.
So we can now design a Mars transport system along the following principles:
— The long-haul journey is accomplished on modular interplanetary cycler stations, which are upgrades of stations in regular use as Earth-Moon cyclers, which are themselves upgrades of stations in regular use in low Earth orbit as hotels, factories and so on;
— The transport chain between Earth and the interplanetary cyclers is closed by short-range ferries, which are upgrades of ferries in regular use to connect with the Earth-Moon cyclers, which are themselves upgrades of ferries in regular use between Earth’s surface and low Earth orbit;
— The bulk of the development work that goes into the first Mars mission is carried out by commercial companies in pursuit of profitable business in space tourism, manufacturing and energy;
— As a result of growth in traffic in the Earth-Moon system, an in-space refuelling system based on near-Earth asteroidal water will become economically viable, vastly decreasing launch costs from Earth.
There may still be a heroic attempt to get to Mars in isolation from the development of such a space economy. If we are lucky, it will be like Apollo, and will be cancelled after the first few landings. If we are unlucky, it will be like the X-33 or Hermès spaceplanes, or like the Soviet Moon-landing programme, and be cancelled before its first landing.
Either way, it will not produce much progress towards sustainable human access to Mars. That can only be achieved by a systemic transport system, not a heroic one.
To conclude, I would remind you of my two key points:
— Most of the mass needed for an Earth-Mars transport system consists of propellants and life support materials, and that is already in space, and already in orbits very close to the ones which we need;
— But this near-Earth asteroidal resource is completely invisible to the space agency paradigm of space exploration, because it excludes the construction of permanent human activity in space.
It is rather unfortunate that the widescreen TV industry has decided to go down the route of an almost outright cheating of their customers, by marketing TV sets around their diagonal size.
Fact (1): Widescreen TVs aspect (ratio between width and height) is 16:9 , “normal” TVs’s 4:3. That is, a widescreen TV of the same height of a “normal” TV, is also considerably wider.
Fact (2): Apart from dodgy movies and panoramic documentaries, most TV broadcasts picture objects standing vertically, eg people walking or talking to each other. Even Italian footballers are shown standing on their feet, most of the time. Therefore, the height of the image is very important in the enjoyment of a TV show.
The above means that anybody buying a 28″ widescreen TV to substitute a 28″ “normal” one, is in for a nasty surprise: the new TV set will be shorter in height, and therefore all the objects on the screen will be smaller.
This may explain a generic sense of disappointment when looking at “small” sets in TV shops, with rather minute screens sporting unbelievable sizes of 19″ or 20″…
Some quick maths can provide guidance: it turns out that to keep the same height, a widescreen TV set’s diagonal size must be around 1.22 times larger than a “normal” one.
So if you want to replace a 28″ TV, don’t ever go for anything less than a 35″ widescreen; a 14″ set, buy a 18″ widescreen or larger; a 32″ “normal” TV, substitute with a 40″ widescreen at least.
Ah…and if you are dreaming of the 42″ widescreen TV sets I can tell you from experience…after two weeks, it will look as small as the old one.
Using the infrared camera in the Wii remote and a head mounted sensor bar (two IR LEDs), you can accurately track the location of your head and render view dependent images on the screen. This effectively transforms your display into a portal to a virtual environment. The display properly reacts to head and body movement as if it were a real window creating a realistic illusion of depth and space.
Dec 6, 1957: Vanguard-TV3, three feet up, still 656,165 to go before reaching orbit…
Ponderously it lifted itself off the pad—one foot, two feet, three feet. For one blink of an eye it seemed to stand still. A tongue of orange flame shot out from beneath the rocket, darted downwind, then billowed up the right side of TV3 into a fireball 150 feet high. “There it goes! There is an explosion!” an observation pilot cried into his radio
News of the failure of TV3 was flashed out around the nation and the world. Impact: shock, scorn, derision. Almost instantly the U.S.’s tiny, grounded satellite got rechristened stallnik, flopnik, dudnik, puffnik, phutnik, oopsnik, goofnik, kaputnik and—closer to the Soviet original—sputternik. At the U.N., Soviet diplomats laughingly suggested that the U.S. ought to try for Soviet technical assistance to backward nations. An office worker in Washington burst into tears; a calypso singer on the BBC in London strummed a ditty about Oh, from America comes the significant thought/Their own little Sputnik won’t go off. Said a university professor in Pittsburgh: “It’s our worst humiliation since Custer’s last stand.” Said Dr. John P. Hagen, director of Project Vanguard, as he got ready to face a doleful press conference in Washington: “Nuts.“
Ad agencies appear to have woken up to the superiority of “portrait” (“vertical”) setting of displays compared to standard “landscape” (“horizontal”): that is, how much more natural and life-like the images look on them.
Why has that happened? Likely for two reasons. First of all, computer screens were originally built using standard TV technology. Television started as a kind of “remote theatre” (most of it, still is). Theatre stages are wide rather than deep, because all actors need to be placed in front of the public and it’s pretty hard to stack them up…the original 4:3 landscape format for TV sets was therefore not a bad choice (even more so, the contemporary 16:9 format).
Furthermore, perhaps since the times of Xerox’s Palo Alto workshop that heralded the era of computer graphics, a PC’s screen has been meant to be a “desktop”…literally, the top surface of one’s desk. Now, office desks are usually rectangular, and this is because of the way we can move our arms (reaching out is much easier on the sides than straight in front of us).
But most of us use computers for reading and writing messages, for blogs and comments, for developing programming code, and in most cases to surf the internet. I am not sure anybody pretends that their few square inches of screen are actually their desktop?
Instead, as books and newspapers are usually in portrait format, and people’s bodies and faces are usually vertically -oriented (that’s why it is called portrait), and even the windows in most buildings are taller than wider…our real-life world is full of portrait-oriented features with which we interact.
It would all look obviously much more natural if we had portrait computer screens. In some cases, even portrait-oriented TV sets.
And that’s in fact what is happening in some airports, where TV screens are being mounted vertically to display advertisements. Whatever is shown, such as panoramas or products, the impression is of looking into a window into another real world, rather than the artificial theatre of television.
So if your screen and your PC’s graphics card allow portrait-orientation, do not hesitate and try it out.
Me, I have no intention to go back to “landscape”.
It has long been common wisdom to have rectangular monitors, be them TV or for PC’s, with landscapeorientation, wider than taller.
Perhaps it is a way of mimicking the movie theatre experience, where such an orientation is in order to serve amphitheatre-like seating, and to provide context to the action.
Recently, things are gone even further down the same path, with Widescreen TV sets (and laptop PC monitors) all the rage.
That may as well be a good choice if all people want to do is watch movies. Not so for Computers of any sort.
Think about it: we are trained to read on portrait-orientedbooks. Even text fonts and standard printer paper are taller than wider (not to mention our bodies, faces and windows apart from exceptional cases).
Most of us use computers for reading and writing messages, for blogs and comments, for developing programming code, and in most cases to surf the internet.
It would be therefore much better to re-orient the monitors sideways, making their long side vertical.
I have been using such a configuration for more than two years and there is simply no comparison regarding having a more natural experience with portrait-oriented monitors, with far less need of eye and neck movements to keep track of the content of the screen.
Portrait-viewing is rather easy to do on a PC (or Tablet PC), but unfortunately next-to-impossible to find on a laptop computer.
But lo-and-behold: Adobe Inc.’s hugely popular Acrobat Reader does allow re-orientation indeed, making reading of electronic documents almost completely equivalent to paper ones’.
Is portrait-orientation the next step towards the utopian dream called “paperless office“? We will know when manufacturers will, one day, pick up such an obvious idea.
The latter article contains sobering statements about the current status of space-travel technology (my emphasis):
For Mars missions, we conjecture a 400-day round trip transit to and from Mars, and about 560 days on the surface. The [Galactic Cosmic Radiation] dose equivalent with 15 g/cm2 of aluminum shielding during Solar Minimum is about double the allowable annual dose for each leg of the trip to and from Mars. If a major [Solar Particles Event] occurred during a transit, the crew would receive a sufficient dose to reduce their life expectancy by more than the 3% limit. […]
On the surface of Mars, the accumulated [Galactic Cosmic Radiation] exceeds the annual allowable [amount]. For a 560-day stay on Mars [it] would exceed the career allowable dose for most females and younger males.
It basically says you’re not just the product of your genes. Or even of your genes and your environment
Your mother may have cuddled you early on out of trouble (on deep into it) for the rest of your life (as reported on The Economist [subscription may be necessary])
Theoretically, your great-grandmother (or much less likely, great-grandfather) may have been exposed to something that slightly changed their cells’ environment, and you are now paying the consequences…even without any changes to your genes
But that is nothing compared to the possibilities that may open if epigenetics is well understood. We could soon get tumors switched off with a relatively simple cellular-level intervention, rather than cumbersome DNA modifications
And by simply changing a few chemicals in a just-fertilized human egg, we will be able to program a genius as the identical twin of a fool
(3) Obviously, a widespread use of podcasts, and their transformation in commercial vehicles with the introduction of very short advertising (and therefore not easy to fast-forward on an iPod or equivalent)
In theory one would also be speaking about DAB, the “digital radio” fanfared in the UK, but despite years going by and an unremitting passion as radio listener, I do not see any future in an expensive technology that basically promises only a cleaner sound (and is still battling with its own million different “standards”)
Personal recording devices, and by that I mean especially mobile phones, will soon become a tool for reasserting our individual rights
Already now, one can record sound and even images with nobody noticing. Pictures are taken with no much of a fuss in the most unlikely of places, and whatever happens in the (connected) world, some sort of audio/video record usually tends to show up on the Internet (newsmedia are starting to make large use of user-provided content).
All you need for your mobile to become an electronic shield is some kind of wireless minicamera and a bit more memory on the phone
Your entire life will then be recordable *
And what could be there to record, as a way of defending oneself? For example: when asked for a bribery, the business person could walk into next police station and deposit the evidence of the crime.
Or when threatened by the mob, he or she will be able to throw back the threat. Or when confronting politicians that are trying to expand their sleaze empire, the “victim” will have the option of cashing in by sending the right files to scandal-hungry magazines
Elderly people will be able to show who attacked them in their house, and which carers treat them inhumanely
Children bullied at school won’t need to hide a thing, and life will become harder for sadistic teachers and nannies as well.
We’ll soon be able to literally see the last thing a murder’s victim was looking at
Even torturers will be in trouble, if they won’t take care of eliminating anything with an electronic memory: and still it may not be enough: one can imagine pictures being downloaded elsewhere continuously (it already happens with some mobile phone providers), so that even if the Bad People snatch the camera, what’s been snapped until then will be left for posterity
Expect a flurry of hi-tech bust-ups then not prepared by police. Ehi, even Robocop got out of trouble by showing what he had recorded.
And expect lots of “interesting” items appear on gossipy and even serious newspapers, mostly during the initial period, with people not smart enough to understand they are being filmed during 99% of their lives.
Things will definitely get better on several fronts for a while (and even if you’re the paradigm of honesty, just be careful about picking your nose in the street: your fame may be preceding you at your next job application)
But surely it will be no Paradise: criminals and evildoers will simply have to find a different way.
Some scandals will turn up to be elaborate hoaxes based on doctored pictures, and no doubt we will see discussions about that at trials, as entertaining as genetics during OJ Simpson’s
Still, it will be a progress. Hypocrisy will need a tad more effort to be maintained.
After all, the only freedom we are losing by getting our lives recorded, is the freedom of not having to face our individual consciences
(* How much memory? 24hx3600s/hx24pics/s=2 million pictures. Say, 320×240=76,800 pixels x 3 bytes = 230kB/pic
So one day is 230kB/pic * 2 million pics = 440 Megabytes. With a good compression rate, 200 Megabytes. Do we want to record while asleep? If not, 180 megabytes may suffice. How long before that much will be available on mobile phones? It is already. Average memory now is a bit more than 400 Megabytes)