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For a planet in the so-called “Goldilocks Zone”, Mars is a pretty wretched place. But despite it’s low gravity, freezing temperatures, and a low pressure oxygen starved atmosphere, both NASA and the private-sector are still determined for American astronauts to be boots-on-the-ground sometime in the 2030s.
While its great that so many people now have interest in exploring the solar system, and even more great that some of these same people happen to be billionaires willing to put their money where their mouth is, the question of whether such missions are actually desirable is all too often brushed aside.
Certainly, Mars is a valuable and relatively nearby resource that can be mined and used as a refueling base for more important missions. And many scientists, in geology and biology for example, are excited by the opportunity for their future colleagues to step-foot on this unexplored terrain and gather a trove of fresh data. But have you ever wondered if it is really necessary for humans to actually go themselves? When one considers the success of the handful of space-probes, the past Mars rovers, and the emerging spectrum of advanced robotics becoming feasible today, it seems obvious that using unmanned probes will always be safer, more efficient, and potentially billions of dollars cheaper than sending humans. And if that’s so, will humans ever have any legitimate reason to leave Earth aside from subverting an existential threat?
The fact of the matter is that the money currently fueling modern space initiatives is probably not being allocated properly. And published proposals are clearly too reminiscent of the financial structure of the Apollo program.
It should be obvious that the 20th century Cold War political-theater put too much emphasis on immediate human exploration “moonshots”, and not enough emphasis on engineering autonomous mining probes or theoretical propulsion technology to be used by future generations. But today’s scientists should be allowed to think like scientists and not like political-pundits stoking their accomplishments and patriotism.
Of course, its quite possible that Homo sapiens will never establish any sustainable colony. Or perhaps it will instead be a descendant of our species that will one day inhabit the planets of this and other stars. Even so, we may still take interest in laying the intellectual foundations upon which some future generations might take advantage. Possibly, as one physicist suggests, we may even be responsible for the creation of the worlds our descendants will one day inhabit.
So how should we define what constitutes a productive and sustainable space program in the 21st century? Well, first we should prioritize maintaining and improving the infrastructure that already exists such as the International Space Station (ISS), as well as reducing the cost of space-launch-systems which is something the private-sector is actually doing a decent job of right now.
Our second priority however, should always be finding the most economic pathway to expanding our reach beyond the edges of the solar system and eventually gaining access to interstellar space. Also, we need to be clear about what we mean when we use words like ‘reach’ or ‘access’, and begin letting go of the testosterone-fueled notion of this generation’s Neil Armstrong embarking upon the conquest of a Vespucci-esque folk hero.
For example, the most promising method of sending a probe to another solar system is detailed by a project known as Breakthrough Starshot. This initiative proposes to utilize a 100GW laser to accelerate gram-scale space probes called StarChips to a velocity of 0.2 c. But while the first StarChips will likely be sterile probes that only transmit information about their target back to Earth, the intersection of emerging nanotechnology and molecular machinery with these interstellar spacecraft could radically alter the way we approach a diaspora into space.
Self-replicating seed factories (SRSF) are theoretical probes which carry infrastructural kits designed to utilize raw material in interest of creating an arbitrary number of duplicate probes to be sent to a greater number of farther out targets, which themselves repeat the same process all over again. As these probes propagate, they demonstrate an exponential growth pattern which enables a large-scale gathering of extrasolar information in remarkably short periods of time. Self-replicating systems in the context of nanotechnology was first brought to light in K. Eric Drexler’s 1986 Engine’s of Creation and if ever realized could easily be paired with the technology proposed by Breakthrough Initiatives.
Given sufficiently dexterous technology, we will be able to send small probes to an optimally chosen location (i.e., a planet with an abundance of desirable elements) to begin construction out of a virtually unlimited supply of raw materials. Having no requirements of human labor or investing in materials, we would never encounter any further cost for the construction or launch of space probes. In fact, the only future financial burden would be to research more advanced propulsion and other technologies which could be transmitted as software updates to the self-replicating systems previously deployed.
Indeed, one can envision a future of self-replicating StarChips breeding acres of factories across billions of interstellar moons from the seed of a few micrograms of nanorobots and molecular assemblers on-board a single initial probe. But in reality 1st generation SRSFs needn’t be so dependent on these theoretical molecular machines and gram-scale probes. (After all, there’s plenty of room in outer-space...)
Project Daedalus was a non-replicating interstellar probe designed back in the 1970s which proposed a two-stage fusion rocket be constructed in Earth-orbit capable of approaching 0.12 c. A self-replicating variation of Daedalus was later published in 1980 by Robert Freitas, hypothesizing the delivery of a macro-scale SRSF with a mass of about 443 metric tons to a distant site. The seed factory replicates many copies of itself to increase it’s total manufacturing capacity, then uses the resulting automated manufacturing complex to construct new probes equipped with their own seed factories.
What Freitas doesn’t discuss is the application of reprogramming some seed factories to suit other purposes. For example, if the technology is sufficient and the targeted system contains habitable planets, the manufacturing capacity of seed factories could also be exploited to construct the infrastructure necessary to facilitate entire human colonies, as well as spacecraft capable of supporting human passengers. If such seed factories were first deployed in our own solar system, we would render the spending on present-day initiatives completely wasteful.
It would then seem that the ideal situation would be to scrap NASA’s bantam Mars ambition and reroute the billions of dollars we save to an international SRSF coalition on the scale of the ISS. Which could probably open a pathway to exploring the solar system and beyond within a century of launch. Meanwhile, the commercial space race can continue making progress developing their own manned-missions to the moon, Mars, or any other near-term accessible terrain without digging into federal resources. To be sure, not all the technology required for SRSF is quite there yet, but neither was all the technology present when President Kennedy announced the original moonshot, understanding that it is only through the most brazen scientific endeavors that such technology can be brought to life.
Unfortunately concepts like an SRSF-Daedalus are unlikely to ever receive funding in the real world. Despite the fact that developing such a program would literally be exponentially more efficient than a manned Mars mission, NASA obviously believes that self-replicating space probes which, though incredibly efficient, are too difficult to explain to the people who write the budget.
In discussing near-term colonization efforts within the solar system we tend to find more economic and political barriers to consider than scientific ones. There is a big difference between SpaceX or any other private company orchestrating a Mars colony under the advisement of NASA, and the United States congress wasting billions on a theatrical flag-planting.
A growing list of startup corporations are now attempting to create a new market of commercial space launch, tourism, and mining efforts. But these companies can afford large costs because they along with their investors are betting big on a sizable return in the (albeit far) future, and private citizens are entitled to gamble with their own resources. The government on the other hand, is basically prohibited from financially profiting from their investments in space, as it is illegal for any nation to claim ownership of a celestial object. Which is another excellent example of why the federal government shouldn’t waste it’s time on Mars, especially at the expense of NASA’s budget for more important work such as climate research.
For several years President Trump has been plugging a future mission to Mars during his endless parade of campaign rallies, and back in 2018, the President presented a list of “Space-Force” insignia proposals to his campaign donors, with one such insignia displaying the slogan ‘Mars Awaits’.
Admittedly the fictional god of war is a fitting mascot for a military branch devoted to fighting equally fictional wars, but it is nonetheless unclear what role the Trump Administration anticipates space-marines playing in a NASA Mars mission. Especially considering the first manned mission planned by NASA isn’t scheduled until 2032. In other words, even if Trump proves to be a two-term president, astronauts won’t enter orbit of Mars for a full eight years after his administration leaves office. So we can probably disregard the preposterous idea of pressure-suits being anywhere near a military conflict for the time being.
But the question we should be asking regarding Mars should be what purpose it may serve to our long-term interests, and how best we can work to meet these goals. If our interests lie in moving farther into the solar system during the next century, we should find the most efficient method of doing so. From a logistics perspective, NASA sending a few humans to the red planet in 2032 may not meet this standard.
Personally, I believe U.S. citizens are far more adept in STEM than most bureaucrats and politicians assume. I also believe that with the right leader, gaining support for a cutting-edge space initiative such as self-replicating space probes would be an awesome and historic presidential achievement.
Outside of Cold War era saber-rattling, manned space initiatives funded by governments are notoriously slow moving. Virtually every U.S. president’s administration since JFK has blabbered on about sending astronauts to Mars at one time or another. By 2032 this will amount to about 70 years of rather impotent propaganda and futile proposals labored on by generations of dedicated scientists and engineers. In-contrast, the international collaboration demonstrated by the ISS is a testament to what can be achieved outside of wartime.
This is why we must revise the way our money is being spent on space initiatives in order to ensure that the majority of available funding is directed toward missions focused on building sustainable infrastructure and not some politician’s nostalgia for the 1960s. This would include diverting funds to develop technology necessary to remotely construct a fuel mining facility on Mars, enabling future probes and manned craft alike to go deeper into the solar system. Additionally we need to focus on local challenges such as extending funding for the International Space Station and developing a plan for it’s successor as well as new efforts of international cooperation in space.
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