Our Future in Space
By David Brandt-Erichsen
Blog> Our Future in Space
ORBITAL SPACE SETTLEMENTS
A landmark paper that showed that planets are not required to support a thriving civilization was published in Physics Today in 1974: “‑e Colonization of Space” by Gerard K. O’Neill. (‑is and many of the references in this article can be found at space.nss.org/space-settlement-library). O’Neill, a physics professor at Princeton University, envisioned large rotating space habitats with an Earth-like environment on the inner surface, with articial gravity produced by the rotation. O’Neill was one of the rst people to ask the question: giv-en current technology (back in 1969), how large could such a structure be built in zero gravity? When the calculations came back with an answer in the tens of miles, O’Neill thought he was onto something signicant. A key idea in O’Neill’s thinking was that such large structures could be built out of material mined from the Moon or asteroids to avoid the high cost of launching out of Earth’s much stronger gravitational eld.Between 1969 and 1974, O’Neill worked out some of the technical details, mostly by himself. By late 1974, O’Neill had linked his ideas with Peter Glaser’s Solar Power Satellite (SPS) concept. SPS’s are large solar collectors in space that would beam energy for use on Earth or in space. O’Neill suggested that they be manufactured out of nonterrestrial material, providing an export product potentially valuable enough to make an O’Neill settlement economically self-sustaining.In 1973, George Hazelrigg, also of Princeton, suggested to O’Neill that the Earth-Moon L4 and L5 Lagrangian libration points might be ideal locations for the large orbiting settlements that O’Neill envisioned. (‑e idea of locating a large structure at a libration point can be traced back further to the 1961 novel A Fall of Moondust by Arthur C. Clarke.)
L4 and L5 are points of gravitational equilibrium located on the Moon’s orbit at equal distances from both the Earth and the Moon. An object placed in orbit around L5 (or L4) will remain there indenitely without having to expend fuel to keep it in position. ‑e orbit around L5 has an average radius of about 90,000 miles, which leaves room for a very large number of space settlements just at this one location—enough even to house the entire Earth’s population! Orbital settlements can be built or moved anywhere in space, and materials in the asteroids are sucient for construction of orbital settlements with a total land area over 3,000 times the land area of the Earth.O’Neill can in some respects be likened to Columbus. Both men brought news of a New World, news that would inevitably change the course of history. In both cases, the New World was distant and expensive to get to, but full of natural resources waiting for its inevitable economic development. In the case of the New World of space, the basics of how to do this have been known for some time. ‑e big unknown is how long it will take.
THE L5 SOCIETY
A year after O’Neill’s Physics Today paper was published, a couple from Tucson, Arizona, Keith and Carolyn Henson, used O’Neill’s mailing list to form the L5 Society to promote these ideas. ‑e L5 Society was founded partly because of Arizona Congressman Morris Udall, who at the time was a serious candidate for President. Carolyn Henson arranged for a meeting between O’Neill and Udall, and Udall emerged quite enthusiastic about the idea. Udall asked for public recognition of his support, and a newsletter was needed for this. ‑e rst issue of the L5 News was published in September, 1975. Consisting of just four pages, it included a letter of support from Udall. ‑e newsletter also said that “our clearly stated long range goal will be to disband the Society in a mass meeting at L5.”Each early issue of the L5 News contained reports of new studies and progress in the eld, but excitement over the L5 scenario probably peaked in 1977. ‑at year produced the third consecutive NASA summer study on Space Settlements and Industrialization Using Nonterrestrial Materials. (‑e study was published in 1979 as NASA Publication SP-428, entitled Space Resources and Space Settlement.)
1977 was also the year that two major books came out on the subject: O’Neill’s classic work, e High Frontier, and T. A. Heppenheimer’s Colonies in Space. L5 members had naively thought that once the word got out about these ideas, everyone would immediately jump on board and say “let’s do it.” But that didn’t happen. By 1980 funding for space settlement studies pretty much ended. In 1987, the L5 Society merged with the Wernher von Braun-founded National Space Institute to form the National Space Society, where the dream lives on. O’Neill did not live long enough to achieve his hope of retiring in space. He died prematurely in 1992 after a long battle with leukemia. (Keith Henson tried to get him to sign up with Alcor, but to no avail.)Underestimating the enormous weight of political inertia that would need to be overcome to amass the resources needed to initiate such a venture, many early L5 members thought that they would really get the chance to personally live in space within their lifetimes. ‑ey had a slogan “L5 in ’95” and it meant 1995, not 2095! At the 1995 International Space Development Conference in Cleveland, I was giving a speech and observed that we had originally hoped to get to L5 by now, but only made it as far as Cleveland!
ENTREPRENEURIAL SPACE COMPANIES
The biggest reason for the lack of major progress in space over the past several decades is the high cost of getting into space. In my opinion, for all its great accomplishments NASA is currently on the wrong path with its Space Launch System, which I call “the monster cost pork rocket to nowhere.” It will never get us anywhere because it is just too expensive to use. ‑e sooner that program is cancelled, the better.But things are now starting to look up in a big way thanks to the efforts of entrepreneurial space companies, most prominently Elon Musk’s company, SpaceX, which he founded specically to “make humans a multiplanetary species.” (Yes, Musk is a planetary chauvinist, but I will forgive him!) SpaceX is the rst to build a rocket designed to cost, and in doing so their current Falcon 9 rockets have already lowered costs signicantly and captured half of the launch market. ‑e next step is making them re-usable, a process well underway. ‑e rst stage is designed to come back and land for re-use, and as of this writing the last 16 launches in a row were successfully landed. SpaceX is also the rst private company to orbit a spacecraft (Dragon) and return it to Earth. ‑e Dragon spacecraft is currently being used to bring cargo to the International Space Station and Dragon 2, when ready, will carry astronauts as well. (‑e Dragon 2 spacecraft uses the same control panel as the Tesla!)In September 2017, Musk announced that he will be gradually phasing out the Falcon rockets (including the upcoming Falcon Heavy) and the Dragon spacecraft and use the prots from them to funnel the company’s entire resources into a new rocket temporarily called BFR (Big Falcon Rocket). Construction will begin in mid-2018 and it will take about ve years to develop. ‑e rocket engines have already been red on the test stand, and a prototype composite fuel tank has already been built for testing (see photo). It will be a fully re-usable two-stage design about the size of the Saturn 5 Moon rocket but with greater lifting power and the lowest use cost of any rocket ever made. It will be able to launch 150 tons of payload to orbit and return 50 tons from orbit. ‑e second stage is a spacecraft that can refuel in orbit and carry 100 passengers to land on Mars. (It is designed to be capable of landing on any solid surface in the solar system.) Musk’s stated goal is to get a million people to Mars and he refers to the planet as “a good xer-upper.”Other companies are involved as well. Amazon founder Jeff Bezos is putting a billion dollars a year of his personal Amazon fortune into his company Blue Origin, which is also building reusable rockets and as of this writing is well under way in constructing a 750,000 square-foot rocket factory near Kennedy Space Center. Although they have not yet reached orbit, they have own (and re-own) re-usable suborbital rockets and are selling their own rocket engines to legacy aerospace companies. Also, Bezos obviously has business acumen. Bezos’ stated vision is “millions of people living and working in space” so he is more in alignment with O’Neill’s vision than is Musk.‑ree other companies are particularly worth mentioning. Bigelow Aerospace, founded and nanced by hotel chain owner Robert Bigelow, wants to build space stations and space hotels with inatable modules, three of which are currently in space for testing (one of them is attached to the International Space Station). Two companies, Planetary Resources and Deep Space Industries, plan to mine the asteroids, particularly for platinum group metals to sell on Earth and for water to sell in space for rocket fuel (hydrogen and oxygen) as well as for oxygen for breathing and, of course, just plain water. ‑e leadership of Deep Space Industries is heavily inltrated by former L5 members.
Interstellar settlement: Orbital settlements could eventually be used as interstellar vessels. Furthermore, as humans spread farther out into the solar system, even Kuiper Belt objects can be used for material to build orbital space settlements. Still farther out, objects in the Oort Cloud could be used. ‑e Oort Cloud extends as much as two light years from Earth, and if the nearest star has a similar Oort Cloud, they may overlap, providing “stepping stones to the stars.” Other stars may or may not have livable planets, but it doesn’t matter because all that is needed is rubble (asteroids) to support a larger population in orbital settlements than what could be supported on planets.Other technologies: Nanotechnology could greatly reduce the cost and increase the re-liability of all aspects of space systems, and Eric Drexler has stated that the strongest materials built with nanotechnology could allow continent-sized orbital settlements. Transhumanism could at least in part adapt humans to the space environment rather than adapting the environment to humans (greater resistance to radiation would be nice, for example). And a space elevator could greatly affect the economics of space. (A space elevator would ride on a cable stretching from the Earth as far as 60,000 miles into space, requiring materi-als stronger than any that now exist.)
It is not certain that the human race will move into space, but there are many drivers to do so: the fact that most of the material and energy resources of the solar system are in space, the historical trend of life lling any available niche, and, yes, the very hu-man desire to boldly go where no one has gone before. ‑e future is likely to be an exciting place, and a major reason for my signing up for cryonics is because I want a chance to see that future and be a part of it.