Starship Century – Right here, Right Now
The Starship is still about 100 years away, but we will begin building it this century. This was the message that Gregory Benford and his mirror-twin, James Benford, were proclaiming together, with the help of notables of both science and science fiction. And me. Just how I got involved is another story, suffice it to say, I know a lot about starships, at least about every variety that has ever been seriously proposed.
The choice of venue and the timing were serendipitous – the Arthur C Clarke Foundation and the University of California in San Diego (UCSD) had been working together on the Arthur C Clarke Center for Human Imagination, and the UCSD is the alma mater of a surprising number of modern day Science-Fiction writers. Over the month of May a variety of events were scheduled, notably a conversation between John Lethem and Kim Stanley Robinson on May 14, but the biggest would be the Starship Century. Not coincidentally there is also an associated book, though when I began working on my chapter contribution over a year ago I had no inkling of the event coming up. The details came together quickly, and are a credit to the organisers, especially Sheldon Brown and his team. The event proper was on May 21 & 22, but a UCSD function the night before set the scene, with the Chancellor and Sheldon Brown explaining what the Arthur C Clarke Center was and how it came about. UCSD is the alma mater for a surprising number of contemporary SF writers – not just the Benfords, but also David Brin, Kim Stanley Robinson, Neal Stephenson and many others – so the idea of Arthur C Clarke’s legacy finding a home there seems fitting.
I had arrived in San Diego that afternoon (May 20), after crossing the Pacific with a tail-wind for 12 hours, and had shared a Shuttle bus to the La Jolla Shores Hotel, where the invited speakers were staying, with John Cramer. I had met John briefly at the Orlando 100 Year Starship (100 YrSS), but had corresponded with him on-and-off for some time. He gave me a quick update on his retrocausality experiments (see his Alternate View column for details) and then we arrived. I grew up on Queensland’s Sunshine Coast so seeing the Pacific, but looking West, took a moment of reorientation. Once checked in I needed to stretch my legs so I walked up the nearest street to the local Cafes and shops, only to run into fellow contributor to the book, Ian Crawford – another alien in this strange land of California. We discussed exoplanets and the fate of ocean planets, whether they would dry out or remain drowned, over the aeons. Returning to the Hotel to get dressed I ran into Greg Benford – who briefly I confused with his brother Jim, as he was wearing a tie – and had an inkling I might be slightly over-dressed.
As with 100 YrSS, much of the discussion and interaction happens “off screen”. I spoke to so many people, several of whom told me amazing things, but I then promptly forgot what was on their name-badges. Familiar faces I quickly caught up with, especially Al Jackson, who has a multi-decadal career with NASA going back to the beginning and co-wrote classic papers on interstellar flight through-out the 1970s. Al astounded me by saying he only managed to see one live launch from Cape Canaveral – STS 135 – even though he had worked with many of the Apollo crews in the 1960s. A new face for me was SF writer Allen Steele, whose work I knew of, but hadn’t managed to yet read. A mutual friend, Winchell Chung, has written up much of the technical details of Allen’s novels on his “Atomic Rockets” website, and has also advised Allen on his more recent works. Other new faces, for me, were the poly-math Eric Hughes, who wrote for “Wired” in the hey-days of Cyber-Punk in the early 1990s; Mark Canter, who is a former editor of “Men’s Health” magazine and these days writes SF novels with a more anthropological basis, and John Chalmers, an astrobiologist who has worked with Stanley Miller on the chemical origins of life. The audience of Starship Century was of stellar quality, how much more so the speakers.
Day One, May 21, began with breakfast watching the breakers and discussing interstellar matters with James Benford. Instead of the UCSD Shuttle ride, I had a lift with Jim and Allen Steele as another passenger. Arriving, the puzzle was where to sit. With so many luminaries in attendance, one doesn’t just sit next to Freeman Dyson without introduction. Jim, Greg and Sheldon Brown [video] opened the day officially, and I sat back to listen to Peter Schwartz, [video] renowned Futurist and long term strategist for some very large companies, discuss the scenarios of the future that might get humanity to the stars.
Peter covered three basic scenarios, though many more can be generated. The full details can be found in the “Starship Century” anthology, but in essence three ideologies could launch us to the stars. Firstly, “God’s Galaxy”, which implies a future Earth dominated by religion, sending forth missionaries to the unconverted of the Galaxy. Secondly, “The Dying Earth”, in which we’re seeking a second home, basically the back-story of “Firefly” and countless other SF treatments. Thirdly, “Interstellar Trillionaires”, in which the ultra-rich of a fully developed interplanetary economy launch forth for adventure or curiosity’s sake. Of course, what applies to us, might also apply to other civilizations, with the logical implications for Fermi’s Paradox. Peter’s response to that, was to suggest that “They” might be too sparsely spread in space-and-time for it to yet be an issue.
Next up was Freeman Dyson [video], who has a deserved reputation as a big thinker, as well as at least one near-miss with a Nobel Prize. In interstellar matters, his seminal popular piece “Interstellar Transport” (1968) described one of the few interstellar propulsion systems we could almost build now – nuclear fusion pulse propulsion. What I hadn’t realised was that the testing ground for “Project Orion”, the USAF/NASA nuclear pulse rocket, was in San Diego – of course, the test models only used high-explosives, but the video available of those tests is quite inspiring. Since the heady days of the 1960s, Freeman has argued more for biotechnology playing a role in our interstellar plans. His lecture covered several ideas he has produced over the last 50 years, namely plant-derived habitats that we might grow on the cold bodies of the outer solar system, and the most efficient means of getting between the stars – send information. Eventually, he suggests, we might launch “biosphere seeds” to other star systems and grow new habitats for Earth-derived life as well as ourselves. Naturally this had ethical reactions from the audience as well as the rattling of chains by the Ghost of Fermi – if we can do it Out There, why hasn’t Someone done it here? After the lecture, during a break, I suggested to Ian Crawford that we might not know our biosphere’s genome well enough to tell if such a scenario hasn’t happened here.
If Freeman Dyson created controversy, the next speaker, Robert Zubrin [video], practically invited it by daring to suggest that Greenhouse warming might be preferable to billions of people living in poverty. Zubrin’s talk covered the economic Big Picture of what was needed to create an interstellar capable civilization, but also provided a chance for Robert to vent spleen about more radical environmental ideologues who are promoting what was once called “Nazism”. Naturally he has a book which covers that particular argument, so I will refer the reader to that for more details. On interstellar matters, he made a powerful case that 100 to 200 years of continued development would see humanity ready to set forth to the stars in the first generation of fusion-propelled starships. My one quibble was the “Energy at Retail Prices” fallacy being used to estimate the economic scale of interstellar flight – a 1,000 tonne spaceship moving at 0.1c and using energy at 10% efficiency would cost $125 trillion in energy bought at the retail rate of $0.1/kW.hr. The problem is that one doesn’t buy energy for a starship and just charge up the batteries. Instead a starship is more like an energy generator – using either solar energy or fusion fuels – and this requires a wholly different economic measurement. The estimates can vary significantly as a result.
Neal Stephenson’s talk [video] was something else again. Not what I expected from an SF writer at all. Instead of Big Picture discussions, he described a vast 20 kilometre Tower that he, and his Arizona State University team, have designed. His talk was thus a detailed look at an advanced theoretical engineering design study in progress. The challenge of such an immense structure, possibly hundreds of millions of tonnes of steel, working in such a changeable environment as the Earth’s atmosphere is fascinating, as is the associated novella in the anthology. But how does it relate to interstellar flight? Naturally the first thing I thought of was as an anchor for a space elevator. Greg Benford suggests another use, in the anthology, but in the current design there is a big empty volume – for future use. A space to fill, for the next generation’s imagination. A reminder, like the Pyramids became, that what one achieves in the present, will look different to the people who come after you.
Lunch at the “Starship Century” Symposium was provided by UCSD, allowing attendees to remain nearby, adding to the discussion and trading of ideas and concerns. Certainly I appreciated the chance to catch up with friends and faces from the other side of the Pacific, as well as meeting new people. Having read people’s novels, books or scientific papers for years, then meeting them on Facebook or email, I felt like I knew some of them already. Meeting authors that I had grown up with like Larry Niven, Joe Haldeman or David Brin was something I was getting used to, as I was more eager to discuss their interstellar ideas than succumb to fan-shock. I finally had my ideas about Larry Niven’s fusion-shield, from his “Known Space” stories, confirmed by the source, but didn’t quite get to talk to David Brin about the Fermi Paradox during the whole event.
The afternoon of the first day was thematically about “New Space” – what we’re doing, as a species, in the near term of a commercial nature. Of course, this was largely from the North American perspective. Patti Grace Smith [video], one of the senior Regulators of “New Space” in Washington DC, spoke about her role in helping commercial space efforts by creating a more operator friendly legal environment. Patti also gave a summary of the key-players in commercial sub-orbital and orbital commercial space efforts, the most prominent being “SpaceX”, while the most secretive has been “Blue Origin”, whom Patti has encouraged to be more open.
Once we’re in orbit the only way is Out – into the wider Solar System. Chemical propulsion isn’t up to the task, so Geoffrey Landis [video] made the argument that Nuclear Thermal Rockets (NTRs) will be the “Workhorse of the Solar System”. Geoff’s presentation was based on material presented previously, to more technical audiences, and the technical reports he referenced are also widely available. So he focussed initially on the long history of the NTR in astronautics – dating back to the late 1940s and almost brought to operational readiness by NASA’s Nuclear Engine for Rocket Vehicle Applications (NERVA) rocket program, before being shelved in the early 1970s. Since then research has focussed on newer materials and newer testing techniques of reactor designs, largely via computer simulation and hot hydrogen gas experiments to simulate the operating environment of engine components. An important point is that NERVA-style NTRs allow transport of humans and their machines in reasonable time-frames all the way to Jupiter. Inside the orbit of Jupiter there exist many sources of the chief NTR propellant – hydrogen – usually in solid form attached to oxygen as water. Conveniently water has many other uses for human beings, thus will be in demand.
That key point lead neatly into the next presenter’s talk [video], Chris Lewicki of “Planetary Resources”, who gave an intriguing overview of the next steps for one of the first “asteroid mining” companies. Chris had clearly covered the material many times before, showing a polish that only comes with practice. The Inner Solar System has abundant energy from the Sun, and convenient chunks of material orbiting in free space in the form of asteroids (and dead comets), but the first task is prospecting and finding the most convenient resources to retrieve from their distant orbits. Thus “Planetary Resources” plan of building small satellites with autonomous control, to minimise ground-control costs, and many of them, to achieve savings via mass-production. Interplanetary prospectors that are cheap enough to crash into an asteroid if that’s what the mission requires. Eventually the quest for precious high-value materials in space to return to Earth, such as the Platinum-Group Metals (PGMs), will also have the side-benefit of producing great volumes of useful in-space materials, such as high-grade iron-nickel metal and water. In time the Inner Solar System could have a viable network of resource trading, with PGMs being dropped back to Earth via “whiffle-balls” of foamed metal, and storage depots of liquid hydrogen for NERVA-style NTRs carrying people to the Moon, Mars and the asteroids.
Panel: The Future of New Space [video]
With those thoughts in mind the day ended with a special presentation and viewing of a small fraction of Arthur C Clarke’s paintings and memorabilia, now at the Geisel Library. Seeing promotional material from “2001: A Space Odyssey”, signed by the actors and similar items made me mindful of the vast legacy that Clarke’s work had inspired. In the nearly 50 years since he began working with Stanley Kubrick on 2001, we have achieved but a tiny part of what the 1960s imagined possible — a reminder of the difficulty of making dreams real.
Intense conversations ate up the hours after the scheduled activities, shadowed by my awareness that I was to be the first speaker on Day Two. My sleep was a broken few hours, an hour at a time, looking at the clock, while my sub-conscious was working on arranging what I would say. Needless to say, I have no idea how the delivery looked [video], as I covered slide-after-slide of starship concepts – most of which are covered in the anthology. One gratifying aspect was being able to point out several starship designers in the audience – Freeman Dyson nodded approvingly when I discussed his Interstellar Orion from 1968, and I covered Al Jackson’s role in the development of the Laser-Powered Ramjet. As a parting note I mentioned the “Ultimate Starship” – my personal suggestion, based on the late Robert Forward’s idea of a neutrino-rocket, to use electroweak unification physics to convert ram-scooped mass directly into a neutrino-jet. One day I will need to write the paper.
Jim Benford [video] covered the concept of Microwave Sail-Ships, giving a fascinating look into his experimental work in the late 1990s, with twin-brother Greg, using carbon-sails in vacuum chambers, made to do amazing things via concentrated beams of polarized microwaves. Jim, like Greg, is a physicist, an alumnus of UCSD, but an applied physicist who has literally written the book on high-power microwave systems, like the million-watt RADAR regularly used by the world’s armed forces. Thus he is well able to discuss the practicalities of propelling sails to interstellar speeds via beams of microwaves and has written several papers covering the economics of micro-wave starships. An elementary conclusion of the Benfords’ experiments is that a conical sail can very effectively ride a polarised microwave beam and be spun so it is self-stabilising. A less encouraging finding is that the cost of energy will dominate interstellar missions at high speeds. Before we can reach the stars we will need to create abundant energy supplies.
Next up was John Cramer [video], a physicist from the University of Washington, well-known to SF fans via his “Alternate View” columns in the “Analog” science fiction magazine, as well as several novels. John focussed on the use of wormholes to allow rapid transit to other star systems. Simply put, wormholes are “tunnels” between two regions in space-time, compatible with Einstein’s equations of General Relativity as one possible mathematical solution. Outside a wormhole itself, observers would see two “ends” of the one space-time structure. Whether wormholes exist or not is a matter for astronomical observation, as larger wormholes should produce distinctive gravitational lensing patterns that astronomers might be lucky enough to see. If the connection formed between the two ends of a wormhole is shorter than the distance through regular space-time, then passing through the wormhole allows apparently faster-than-light travel, though nothing ever exceeds lightspeed locally. Thanks to time-dilation — the slowing of time experienced when approaching lightspeed — a time-lag can be developed between the two ends if one end is sent to a distant star. For example, if a one end is accelerated to a time-dilation of 7,000 (0.99999999c), then only 75 minutes is required for the travelling end to appear to travel 1 light-year from the stationary end’s point-of-view. John Cramer discussed how this might allow a network of rapid-transit wormholes to be set-up throughout the Galaxy – with the caveat that the network can’t be allowed to form a “Closed Time-like Circuit,” else this might destroy the wormholes via amplifying quantum fields.
Before lunch, British astronomer Ian Crawford [video], a fellow member of “Project Icarus”, discussed what we might find amongst the nearer stars, out to 15 light-years. A planetary system probably exists around every star, something we can say with statistical confidence thanks to the work of the “Kepler” exoplanet detection mission, but discerning every planetary system will require improvements on current techniques. And we almost certainly haven’t found every small star within 15 light-years yet, as the 2013 discovery of a brown-dwarf binary at just 6.5 light-years should remind us. Ian made the forceful point that even with vast telescopes able to image those many new planets and stars, there’s only so much we can learn via telescopes. If we find a planet showing all the signs of life, we will only know more by actually going there – via robotic proxy, in Ian’s opinion.
Once we do go, will we survive? This was the after-lunch opener from Paul Davies [video], who posed the puzzling question of how terrestrial life might interact with truly alien life in another star-system. Could they co-exist, with no biochemical compatibility at all? Could they share common simple biochemicals, but foreign genetic and protein chemistry? Or could the two integrate in ways we haven’t yet imagined? Even more intriguingly, Davies suggested that we might already co-exist with “alien” biochemistries on Earth – organisms might exist in niches that otherwise exclude our kind of biology. A suggested location might be at temperatures higher than what known microbes can tolerate, or in highly alkaline fluids, such as what seeps from ocean thermal vents. Davies has suggested, in more than one book, that any life on Mars shares a common ecosystem with Earth, due to the trade in meteorites between the planets over the aeons. Mentioning this sharing of life between planets produced an out-burst from Robert Zubrin, who is an advocate of interstellar transfer of life throughout the Galaxy. A credit to Davies, his response was more interested curiosity than the reflexive dismissal Zubrin seemed to expect. His answer was that we simply don’t know enough to rule out the possibility and they should discuss it more later.
The Benfords encouraged researchers to be present in the audience, with divergent points-of-view. Despite their difference these all share a desire to bridge the space between the stars, but differ in details of how and why we’ll go to the stars. The next speaker unified the many voices by sharing his sense of wonder at the Universe, through a living work of art – Jon Lomberg [video] and his Galaxy Garden. Long-time readers of “Centauri Dreams” will know of Jon Lomberg’s artwork for Carl Sagan’s “Cosmos” in the 1970s and his Galaxy Garden in Hawaii. Having Jon share it with us, a guided-tour in slides, was inspiring and drew multiple rounds of applause from the audience. As Jon put it, we can be Citizens of the Galaxy now.
Two discussion panels concluded the Symposium. The first, chaired by Jill Tarter of the SETI Institute, featured Ian Crawford, Robert Zubrin, Geoffrey Landis, Paul Davies and myself. Our theme was “Getting to the Target Stars” [video] but with Jill as the Chair we wandered into the Search for Others who might have made the same journey. Jill gave a brief summary of false-positive detections of extraterrestrial technology, which have proven to have natural explanations. The sole exception, the distinctive spectroscopic signature of tritium, has no natural explanation – if it is ever detected. With that in mind each of the panellists made suggestions about how we might detect aliens. Robert Zubrin mentioned the distinctive radio output of a starship deploying a magnetic sail, while I suggested the Solar System be searched for dead Starships, since not everyone succeeds in their long voyages. A final task was to sum up how we thought humanity would go to the stars. A common feeling seemed to be via robotic proxies, or nano-bots. In my opinion, by the time we are ready, the distinction between “human” and “robotic” might be meaningless or arbitrary – thus my quip “Nanobots are people, too.”
The final panel was a perspective [video] by the Science Fiction writers, some involved in the “Starship Century” anthology – Joe Haldeman, David Brin, Larry Niven, Vernor Vinge – and Jon Lomberg. This was the artistic side of the event, as all these have produced visions of the starship era. The general feeling was that, given the growth in space industry that Chris Lewicki and Robert Zubrin advocated, then we would see the first star-voyagers depart in about 2200, as Freeman Dyson had extrapolated back in the late 1960s. Some envisioned the unexpected – the discovery of extraterrestrial intelligence near enough to communicate with; breakthroughs in physics that would allow rapid interstellar travel; or, as Allen Steele depicted in his award-winning “Coyote” series, the rise of a tyrant putting a nation or the world on a crash-course program of starship-building. As always, the future will surprise us, but we can prepare ourselves by listening carefully to the modern-day prophets.