Space advocacy
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Space advocacy is a movement which promotes activity in space, or human presence in space. Today the movement is based in the USA. Excessively enthusiastic space advocates have been called space cadets. In the 20th century the movement was closely linked to science fiction fandom, through which it influenced many people who became very wealthy in the software industry in the 1990s and 2000s such as Jeff Bezos and Elon Musk. As of 2025 it has more funds than ever before even if its support base remains modest (membership in the Planetary Society, an international advocacy organization, peaked in 1989).[1] There are tensions within the movement between those who want humans to expand into space and those who are happy sending telescopes and robots, between those who want knowledge for everyone and those who want to claim resources for themselves, and between those who like partnering with governments and armed forces and those who think they get in the way or militarize peaceful exploration.
History[edit]
In the first half of the 20th century, some people started to actively argue for human presence in space, rather than just speculating that it might be possible or telling stories about flying into the void on a chariot pulled by giant swans. Mystic Nikolai Fyodorov (philosopher) was followed by engineers such as Konstantin Tsiolkovsky
in the USSR, the Verein für Raumschiffahrt
(Society for Space Travel, est. 1927) in Germany, and the British Interplanetary Society
(est. 1933). The United States had two organizations, the American Rocket Society
(est. 1930) founded by science fiction writers in New Jersey and GALCIT / the Jet Propulsion Laboratory
founded by Jack Parsons and fellow graduate students in California in 1936. Pulp science fiction presented Mars and Venus as no more hostile than Libya or Papua New Guinea which Europeans were colonizing.
In the postwar period, the Soviet and American space programs had some exciting successes. Humans launched Sputnik and other satellites into orbit, send robot probes to the planets, and landed on the Moon. Significant figures in this period included science fiction authors like Arthur C. Clarke and Robert A. Heinlein and war-criminal rocket scientist Wernher von Braun
. By the 1970s, believers started to feel that not everything was headed where they wanted it to go. Doing things in space was very expensive, with a cost in the tens of thousands of 1999-dollars to put 1 kg in orbit. Satellites were immensely useful for spying and communication, but other industries in space were not developing. Robotic missions took years of preparation and often failed spectacularly when Venus' surface was more hostile than anticipated[2] or someone messed up converting between US customary system and metric.[3] Instead of going to the planets, humans were visiting ramshackle space stations in low Earth orbit such as Mir
and Skylab
. Everything was slow and bureaucratic and required compromises to keep politicians voting for funds or the military supporting the civilian space program. Notable names in this period included Robert Zubrin
, Jerry Pournelle
, Gerald K. O'Neill
, and Carl Sagan. Space advocates who doubled down on the original vision often embrace doubtful ideas. This page focuses on those ideas and not the side of the movement which is more friendly to RationalWiki. SETI is fun, science-based, and not very expensive.
Anarcho-capitalist or Libertarian side[edit]
If NASA is disappointing, maybe private companies should get involved? The government could motivate them to compete for cash prizes. These were inspired by the Longitude Act (UK) of 1714 and lead to the Ansari X Prize. If these worked once, surely they can solve all the problems which limit human activity in space. Or perhaps the solution is privatization and NASA should focus on pure science and hire private companies to do everything else?[4] American space advocates lament that its hard to lead a plan from conception through ten or twenty Congresses until completion, and making programs dependent on businesses which issue quarterly reports to stockholders or single eccentric entrepreneurs sounds much more stable.[5]
Working with governments requires talking and compromising the pure engineering, and most investors want a plan to make a profit soon. Wouldn't a single wealthy patron let space advocates skip all this? But crewed spaceflight is jaw-droppingly expensive. The Apollo 11 moon landing cost about $102 billion in 2015-dollars, about the net worth of any of the 20 richest people in the world in 2025.[6][7] Even if one of the richest people in the world devoted all his wealth to crewed spaceflight, such a patron might die, lose interest, or interfere in things which he was not competent to interfere in. Being rich means you are a genius right?
If all the astronauts are volunteers, and all the investors are using their own money, doesn't that simplify the ethics? That depends on your point of view, but the risks of spaceflight can be truely gruesome, and do not necessarily lead to a quick death. Its easier to imagine heroically dying in a rocket crash than heroically going blind because your mission planners never solved eye degeneration in free fall.[8][9]
Could we finally build Libertarian paradise in space out of reach of governments? A pure capitalist society where even the oxygen is manufactured and home is a six-month rocket trip away sounds delightful.
Actually existing space programs are totally dependent on government contracts, regulation, and a global technological system. Living in space requires extreme cooperation because any mistake can kill everyone. If your cooling plant fails because a valve was the wrong alloy, its cold comfort that your heirs can sue the suppliers. Surprisingly, Libertarian science fiction is a whole subgenre.[10][11]
Space Nazis are also a trope, but space advocates rarely identify with them.
Dubious fundraising[edit]
Space is big, but its also expensive. Ordinary space advocates can only fund small projects with budgets in the millions of dollars like a demonstration of a solar sail.[12] In the 21st century, some billionaires fund commercial space companies such as SpaceX and Blue Origin, but their resources are not unlimited. Other possible sources of funds are either selling space-based goods or services, or asking taxpayers for help.
Intelligence agencies and telecommunications companies will pay for satellites, so how about we launch them like a Starcraft champion making Zerglings? The private space companies of the 2020s love this idea. For sure, these cheap disposable microsatellites emit light and radio which are very noticeable at night. Astronomers like Sam Lawler don't have a lot of money or political influence when their telescopes are blinded, these short-lived satellites have not crashed on anyone important yet,[13] and Kessler syndrome is just a theory.
Space tourism (or launching symbols and memorabilia like human remains, religious symbols, and lists of donors into space) seems barely viable as of 2025. It depends on a handful of wealthy clients, uncrewed missions often go wrong, and crewed missions are often very short. The private Peregrine Mission One
launched samples of the cremains of Gene Roddenberry and Arthur Clarke towards the moon but something went wrong and it burned up in the Earth's atmosphere in 2024.[14] That has not stopped some space advocates getting very enthusiastic about space tourism and dreaming of hotels in orbit or resorts on the Moon.
Supporters of public funds for crewed spaceflight often boast of their amazing benefits for healthcare or industry. Critics such as Maciej Cegłowski argue that most of their R&D goes into keeping the crews alive in space, and most of the science could be described as "do something in space, and see if it is different than on Earth."[15] Crewed missions are good publicity, but they are very expensive, and the public like photos from the Hubble Space Telescope and press releases about robotic landers too. If the arguments about economic benefits of crewed missions are just an excuse, telling a noble lie never worked out badly for anyone did it?
Speculative engineering and pseudoscience[edit]
Maybe there is a miraculous resource in space like Helium-3 in the lunar regolith? We don't know how to make fusion power, and we don't know there is useful 3He on the moon, but if there was and it was key to fusion power it would give us a reason to go there.[16]
What about asteroid mining?[17] There's iridium in them thar hills! Proposals for asteroid mining either propose producing resources to sell on Earth, or producing resources to use in space, avoiding the cost of launching them into orbit. The miners would just have to find the right asteroid, then invent freefall smelting, then beat Earth-based prices but avoid flooding the market. They would also have to convince governments on the ground that they would not accidentally drive an asteroid into a collision course with Earth, or keep their products in distant parts of the Solar System. As yet asteroid mining remains hypothetical, and its not clear that it would involve those pesky Belters and their torchships.[18] Robots and remote-controlled vehicles don't need expensive life support. For space advocates who want humans in space, this is disappointing.
The cost of getting a kilo into orbit is a problem that space advocates like to think about. A space elevator could reduce that cost, it just requites materials with incredible properties and would devastate a line hundreds of kilometers long if it ever broke.
Some space advocates want to place weapons in space to bombard the Earth, whether Wernher von Braun's orbital atomic bombs or Jerry Pournelle's tungsten rods (Kinetic bombardment). It turned out to be more practical to launch missiles briefly into space than to keep them there indefinitely, and even if you could solve the launch cost problem and wait for a launcher to orbit over a target, kinetic impactors entering the atmosphere would throw up a layer of plasma which made it very difficult to correct their course as they approached the target.[19] A bunker-buster which lands somewhere in a 100-metre radius is not very useful. This has not stopped air and space forces from tinkering with the idea!
Other space advocates want defensive weapons in space to shoot down oncoming missiles and their nuclear warheads. The first major project along these lines, the Strategic Defense Initiative, has its own page. The proposal caused a major split among space advocates between those who admired Ronald Reagan (or wanted Defense Department funding) and those who thought the project would demand "technological obscenities."[20]
The rocket equation is cold, and actually-existing spacedrives don't have as much zip as we could hope for. A Hohlman transfer orbit is slow and does not let us jaunt towards Saturn anytime we please. What if the Dean Drive
works or the EmDrive is real? Reactionless propulsion violates physics as we know it but would let humans zoom around the solar system.
If you want to explore the galaxy, Einstein's relativity is depressing. The first space advocates lived before it was known that the speed of light is an absolute limit. What if exotic propulsion methods such as the Albucierre drive work?
Anti-relativity and reactionless drives seem marginal within space-advocacy circles in 2025, but were popular among science-fiction fans and writers in the 20th century. One tension within space advocacy is between the anarcho-capitalist side and those who dream of megaprojects like Dyson spheres or exploring the galaxy on solar sails driven by giant laser beams. Even the wealthiest billionaire can't dismantle Saturn for spare parts.
Apes in a can[edit]
Automation keeps getting better and better, but humans will always need food, air, and water, be vulnerable to radiation, and be prone to arguing or snogging when they should be watching that collision alert. Science fiction writers sometimes dream of sending up eighteen-year old construction workers instead of 35-year-old PhDs, but the market for unskilled labour is shrinking even on Earth.[21] This is a problem if you really want humans in space.
Since the 1960s, evidence has grown that living in freefall and exposure to radiation outside the Earth's magnetic field have serious health consequences.[22][23] Most astronauts' bones rapidly lose mass, even with ninety minutes per day of mandatory exercise on a treadmill (although some with the right genes are immune).[24][25] As of 2025, space stations rely on frequent deliveries of food, clothing, and spare parts, and astronauts can return to Earth in case of a medical emergency. A longer mission to the Moon or Mars would need to be self-sufficient. Building a closed-loop life-support system is extremely difficult, and the Biosphere 2 project in the USA was not a success. While some space advocates like Andy Weir
enthuse about the details of life support and space gardening, others prefer to wave their hands and hope that if they build a really big rocket, the messy bio problems will sort themselves out.
After about six weeks living in close quarters, humans tend to get annoyed with each other (cabin fever or irrational antagonisms).[26] For the foreseeable future, a mission to Mars would require 500 days at close quarters, and an early Moon base would be cramped too.[27] Isolated campers can go for a walk to get away from their mates but there would be no way to get away from crewmates on a ship between planets. Space agencies are cagey about the forms those antagonisms have taken, but one American astronaut was arrested after bringing pepper spray, a knife, and a hammer to greet a love rival at the airport, a simulation of confined living in 1999/2000 was disrupted when one participant forcibly kissed another and two others got into a fistfight,[28] and the crew of the Soviet Salyut 5 mission had to return early when they broke down from stress after an electrical failure on day 42 in 1976.[29] Astronauts on spacewalks are subject to space euphoria (a feeling of godlike joy) and vertigo.[30] Good astronauts are stolid, highly educated, and good at following checklists, but long missions to space stations are very difficult for them, and a mission to another planet or a base on the Moon would be even more difficult.[31]
Another thing that people trapped in confined spaces do is have sex. Officially, all astronauts have kept their hands to themselves until returning to Earth, viral emails to the contrary.[32] Sexual tensions lead to bad decisions, and no company or space agency wants a story about an orbital love triangle to appear on social media. People separated from their partners for months or years also do strange things. People in the space community have debated what to do about this.[33] Some propose sending married couples into space because lovers never quarrel, break up, or cheat on each other. Others propose single-sex crews or asexuals because lonely men never play with each other. A third approach is just accepting that on long missions, astronauts will acquire space boyfriends and space wives for the duration of the mission, like researchers who overwinter in the Antarctic.
Setting space would require having children there. As of 2010, there had been few experiments with mammalian reproduction in space, but radiation is dangerous to sex cells and freefall has serious health consequences. Science fiction from the 20th century often assumed that those born on the Moon would be unable to survive on Earth and people would have children anyways, but that sounds unethical.
Moon dust is nasty: it corrodes equipment and gets into lungs.[34][35] The soil of Mars is tainted with toxic perchlorates.[36] These problems could be mitigated by the right equipment and processes, like never bringing spacesuits into the habitation area, and washing Martian soil with water before using it to grow plants, but could not be ignored. European explorers in the Arctic and Antarctic faced many health challenges, even though indigenous people were already living successfully in the Arctic.
If other worlds are hostile to human life, perhaps they could be terraformed to be more like Earth? This is possible in principle, but healing Earth from climate change or the fallout of a nuclear war might be easier. So even if it were possible, that might not be a good argument for settling humans on Mars. The costs and technologies involved put terraforming far in the future if it happens at all.
Reducing the cost of launch would allow spacecraft to include more radiation shielding, and perhaps even allow space stations to be so big that they could spin to simulate gravity. (No current or near-future technology could give noticeable acceleration for days or weeks at a time, like astronauts launching into space are pushed towards the back of the rocket by the force of the launch). The other difficulties would remain. Because humans' only experience in low gravity has been the six Apollo landings, it remains to be seen whether living in low gravity is much healthier than living in freefall.
Automated and remote-controlled missions like the Mars Exploration Rover and Chandrayaan-3
have none of these problems, and when they fail nobody dies.
Existential risk[edit]
Another argument is that if humans settled on the Moon, Mars, or even other solar systems, humanity would be less likely to become extinct. Couldn't an asteroid impact, a gamma-ray burst, or nuclear war sterilize the earth? Advocates often intone "Earth is too small a basket for mankind to keep all its eggs in" or point out that the dinosaurs didn't have a space program.[37] That might have made sense a hundred years ago, but we now know that the moon and Mars are more hostile to human life than the most remote parts of Earth. Putting not just a few hundred people, but enough to sustain civilization, in space would be mind-boggling expensive. And many dangers to humanity come from other humans, such as nuclear war and climate change. Even if humans on earth blow themselves up, humans on Alpha Centauri could blow themselves up too. Daniel Deudney has expanded this argument into a whole academic book, noting that plans to colonize the solar system often increase the risk of war or environmental catastrophe on earth. Intercontinental ballistic missiles which pass through space on their way towards their targets have surely done more to endanger the future of humanity than the Apollo Program or Tiangong have done to protect it.
Some people want to risk their lives in space rather than have long but quiet lives on Earth. The idea of one-way trips comes up every few decades. At the beginning of the American moon program, several engineers proposed sending a man to the Moon first, and figuring out how to get him back later.[38] The Mars One project claimed that it would send astronauts on a one-way trip to Mars,[39] and Elon Musk warned that his own proposed Mars mission would be "really very dangerous."[40] Under the current understanding of physics, interstellar trips would almost certainly be one-way too, since voyages between stars would take decades or centuries. Space advocates often dream of making humanity immortal, but some are willing to give up their own lives early to make that happen.
Cults of personality[edit]
Space advocacy has always been tied to fiction where a handful of protagonists have adventures and achieve great things. The space programs which put humans in orbit and on the moon were giant bureaucracies with tens of thousands of skilled workers, each of whom could only understand and influence a tiny part of the problem.[41] If you want to be the main character, that is disappointing. Space advocates in the USA tend to cluster around individuals, whether inspiring science-fiction authors or entrepreneurs. Walter Cronkite called von Braun "the New Columbus" although the good doctor acknowledged that "space exploration is not a one-man show."[42] You can find globe-trotting journalists who promise that Elon Musk's charisma, genius, or wheeling and dealing are about to revolutionize spaceflight and his erratic behavior is just the price of genius.[43] The stories about four teenagers and their eccentric uncle building a spaceship prepared people to trust anyone who seems like a space genius.
Because they are private companies, there is some question about how much companies like SpaceX have reduced the cost of launch (around $3,000 or $6,000 per kilo circa 2020?).[44][45] Private companies quote much lower prices than public space agencies, but those private companies do not have to be as transparent as government agencies or companies on the stock market.
The very wealthy individuals who fund private space companies include some curious characters. Hotel magnate Robert Bigelow gave up his plans to build a hotel in orbit in 2020 but is still investigating extraterrestrials and life after death (he was also the onetime owner of Skinwalker Ranch). No doubt space advocates from the reality-based community can take their money, spend it exactly how they want, and not get pulled into the fringe world.
Nationalism and internationalism[edit]
Is space an environment where all nations can work together in the pursuit of knowledge? An excuse for Americans to pay Russian scientists so they don't decide to build missiles or bombs for the wrong clients? Or an excuse to beat your chest like a gorilla and scream slogans? The American space advocates on the Planetary Radio don't say as much about Chinese or Russian projects as American, European, or Japanese projects. Whereas it once cooperated with Russia, NASA is forbidden by the Wolf Amendment from cooperating with Chinese space programs without specific congressional approval. The Outer Space Treaty
forbids some fun activities like testing weapons on the Moon or claiming territory on Mars.
Transhumanism[edit]
Keeping primates alive in space is hard. Taking more risks did not go well for Stockton Rush's Titan submersible. What if we make humans better able to survive in space with genetic engineering or nanotechnology? Just by trying we might solve longevity!
What about inducing hibernation or suspended animation in astronauts before long voyages? Bears can hibernate, and microbes can enter a suspended state and recover when a hospitable environment emerges, which is wonderful if you want to build an interplanetary wildlife refuge or microbiology lab. There is no reliable way to induce these states in humans. If it were possible, it would reduce the consumption of food and water and the psychological tension on long voyages, but be another thing that could go wrong.[46] More ambitious versions of these ideas have the same problems as cryonics with the addition of a radiation bombardment and a tiny team with limited equipment to revive the sleeping astronauts.
What if we turned humans into something else and send mind-uploads or eggs, sperm, and mechanical wombs to distant stars? We don't know how to do any of those things so we can imagine they would solve our problems.
What if we sent posthuman entities like a self-replicating von Neumann probe? Probes which arrive in a star system, replicate themselves and their fuel, and launch copies to new star systems could explore the galaxy one centuries-long jump at a time. Machines do not age, change their minds, or need air and water, but they can break down over time.
Several of the earliest space advocates were Russian Cosmists, so the movement is connected to the TESCREAL ideologies. Some Latter-Day Saints are very interested in space because space advocacy and transhumanism have some similarities to teachings like the celestial exaltation.[47]
Conclusion[edit]
Space advocacy includes some sympathetic ideals, some ugly politics, and some crazy ideas. This article does not discuss the first kind because organizations like the Planetary Society will tell you everything you want to know about why the JWST is awesome. The weirder ideas are often recycled from the 1970s and earlier, or inspired by science fiction (Elon Musk looks kind of like Delos D. Harriman if you squint, and both he and Jeff Bezos grew up on stories by space advocates). Space advocates oppose doubtful ideas that would get in the way of human presence in space such as the Moon landing hoax, but can be tempted by ideas that fit their politics or their dreams.
Further Reading[edit]
- Christian Davenport, Rocket Dreams: Musk, Bezos, and the Inside Story of the New, Trillion-Dollar Space Race (2025)
- Daniel Deudney, Dark Skies: Space Expansionism, Planetary Geopolitics, and the Ends of Humanity (Oxford University Press, 2020) Reviewed in Bryon Williston, The Case Against Mars, Boston Review, May 26,2020
- Howard E. McCurdy, Financing the New Space Industry: Breaking Free of Gravity and Government Support (2019)
- Oliver Morton, Mapping Mars: Science, Imagination, and the Birth of a World (2002)
- Phil Plait, Death from the Skies! These Are The Ways The World Will End (2008)
- Mary Roach, Packing for Mars (2011)
- Kelly and Zach Weinersmith, A City on Mars: Can We Settle Space, Should We Settle Space, and Have We Really Thought This Through? (2023)
References[edit]
- ↑ Our Story, The Planetary Society
- ↑ Doug Adler, The Venera program: Interplanetary probes from behind the Iron Curtain, Astronomy Magazine, May 9, 2025
- ↑ Robert Lee Hotz, Mars Probe Lost Due to Simple Math Error, Los Angeles Times, October 1, 1999
- ↑ Jerry Pournelle, Why Have NASA and What are X Programs?, Testimony to Subcommittee on Space, March 16, 1995 archived https://archive.ph/zrN4I
- ↑ Maciej Cegłowski, Why Not Mars, Idle Words, January 1, 2023
"To borrow a quote from John Young, keeping such a program funded through fifteen consecutive Congresses would require a series 'of continuous miracles, interspersed with acts of God'."
- ↑ Kelly Dickerson, Two MIT students lay out the facts about why the Mars One mission is bogus, Business Insider, September 18, 2015
- ↑ Bloomberg Billionaires Index, Bloomberg.
- ↑ Risk of Spaceflight Associated Neuro-ocular Syndrome (SANS) nasa.gov
- ↑ Lee, A.G., Mader, T.H., Gibson, C.R. et al. Spaceflight associated neuro-ocular syndrome SANS and the neuro-ophthalmologic effects of microgravity: a review and an update. npj Microgravity 6, 7 DOI 10.1038/s41526-020-0097-9
- ↑ Libertarians in Space. TvTropes
- ↑ Matt Novak, Libra: The 21st Century (Libertarian) Space Colony, Smithsonian Magazine, February 15, 2013
- ↑ LightSail, a Planetary Society solar sail spacecraft, The Planetary Society
- ↑ Samantha Lawler, A New, Deadly Era of Space Junk Is Dawning, and No One Is Ready, Scientific American, July 10, 2024
- ↑ Marcia Dunn, Remains of sci-fi legends burn in Earth’s atmosphere, The Sydney Morning Herald, January 19, 2024
- ↑ Maciej Cegłowski, A Rocket to Nowhere, Idle Words, August 2005
- ↑ Greg De Temmerman, The helium bubble: Prospects for 3He-fuelled nuclear fusion, Joule, Volume 5, Issue 6, 16 June 2021, pages 1312-1315 https://doi.org/10.1016/j.joule.2021.05.003
- ↑ John S. Lewis, Mining the Sky: Untold Riches from the Asteroids, Comets, and Planets (1997)
- ↑ Jerry Pournelle, "Those Pesky Belters and Their Torchships" in A Step Farther Out (1979)
- ↑ Hypervelocity Rod Bundles (HRB) GlobalSecurity.org
- ↑ Alec Nevala-Lee, Astounding (2018) pages 388, 389
- ↑ Jerry Pournelle, Chaos Manor Mail, March 5-11, 2001 archived https://archive.ph/1FcjD
- ↑ Would astronauts’ kidneys survive a roundtrip to Mars? UCL News, 11 June 2024
- ↑ The mysterious aging of astronauts. Daniel Lemire's Blog, December 1, 2015
- ↑ Mary Roach, Packing for Mars (2010) pages 218-224
- ↑ Everyday Life in Space. European Space Agency
- ↑ Mary Roach, Packing for Mars (2010) pages 52-53
- ↑ The Shape of a Mars Mission, Idle Words, February 2025
- ↑ Mary Roach, Packing for Mars (2010), pages 45-47
- ↑ Mary Roach, Packing for Mars (2010) pages 73-76
- ↑ Mary Roach, Packing for Mars, pages 66-71
- ↑ Mary Roach, Packing for Mars (2010) pages 36-37
- ↑ Oliver Tryst. snopes.com
- ↑ Mary Roach, Packing for Mars (2010) pages 59-61
- ↑ Pohlen M, Carroll D, Prisk GK, Sawyer AJ. Overview of lunar dust toxicity risk. NPJ Microgravity. 2022 Dec 2;8(1):55. doi: 10.1038/s41526-022-00244-1. PMID: 36460679; PMCID: PMC9718825.
- ↑ What Hazards Are Caused by Lunar Regolith? science.nasa.gov
- ↑ P.D. Archer et al., Perchlorate on Mars – Overview and Implications, NASA 2019
- ↑ Great Space Quotes, spacemonitor.blogspot.com, July 5, 2007
- ↑ Mary Roach, Packing for Mars (2010) pages 166-168
- ↑ Mary Beth Griggs, All the countries (and companies) trying to get to Mars, Popular Science, September 29, 2017
- ↑ Ali Sundermeier, Elon Musk: To Join SpaceX's First Mission to Mars, You Have to Be "Prepared to Die", ScienceAlert, September 28, 2016
- ↑ NASA Workforce Chart, The Planetary Society
- ↑ Bob Ward, Dr. Space: the Life of Wernher von Braun (New York : Naval Institute Press, 2013) page 257
- ↑ Gwynne Dyer, The Very Precious Life of Elon Musk, gwynnedyer.com, August 21, 2024
- ↑ Harry Jones, The Recent Large Reduction in Space Launch Cost, 48th International Conference on Environmental Systems, 8-12 July 2018, Albuquerque, New Mexico
- ↑ How Much Do SpaceX Rocket Launches Really Cost? Faustus Notes, November 23, 2018
- ↑ Roach, Packing for Mars, pages 224-226
- ↑ Danielle Wiedner-Bronner, Mormons Don't Technically Get a Planet Once They Die, Say Mormons, The Atlantic, February 2014