I just finished reading Dr Robert Zubrin’s The Case for Mars (TCFM), which I bought from the man himself when he was last in Adelaide. Dr Zubrin is the president of the US Mars Society, a group which advocates sending a manned mission to Mars. Zubrin creates a rather compelling case for why we should send such a mission and how we could do it. The book is somewhat anti-NASA with the author expressing his frustration that we could get to the Moon in the 1960’s, yet can’t get back today, let alone get to Mars. There is a recurring theme that we are doing less with more than our space faring predecessors. I’ll cover several key ideas of the book, including the plan to get to Mars, then how to colonise and terraform the red planet, and add my own ideas.
Zubrin’s plan to put humans on Mars is dubbed the Mars Direct Plan. A bit of background: due to the rate at which Earth and Mars orbit relative to each other, the ideal launch window for a mission to Mars opens up once every 2 years. For a mission with reasonable propulsion capability, it should take around 6 months to get there. One of the biggest complaints about sending a human mission to Mars is the fact that it would be too hard to bring all the fuel you need to launch back to Earth from Mars’ surface. So – going to Mars would be a death sentence, so to speak – a little off-putting for some. The Mars Direct mission utilises in-situ propellant generation, creating a fuel from Mars’ atmosphere via a series of chemical reactions using a feedstock of a small quantity of fuel brought from Earth. This means that we don’t have to bring the fuel with us, and we can return humans to Earth.
We start by sending an unmanned Earth Return Vehicle (ERV) to Mars with in-situ propellant generation capabilities. This travels for 6 months then lands. It spends the next 18 months generating fuel. By this time, we are about ready for the next launch window. We remotely test the ERV to make sure it’s good to go for return, then send the first human mission and another ERV. The second ERV can act as a spare if the first doesn’t work, but more importantly can repeat the same process to prepare for the next human mission in 2 years.
I could go on at length about the numerous technical aspects. You can either trust me that Zubrin does a good job at covering all the bases or you can read the book yourself! But note that this plan doesn’t necessarily involve futuristic technology. A lot of the infrastructure required (including the in-situ propellant generation) exists now.
One idea proposed to encourage Mars exploration is dubbed the ‘Gingrich Approach’. This involves creating a series of challenges, each with its own cash prize, culminating in the ultimate prize of ‘Be the first to send a crew to Mars and return the crew members safely to Earth‘ with a reward of $20 billion US, plus $1 million per person for each day spent on the Martian surface, up to a maximum bonus of $5 billion. Not bad! I’d certainly put my hand up to spend 18 months on Mars for $1 million a day! Similar competitions exist, such as the Google Lunar xPrize. The idea is to create a financial incentive for private entities to explore Mars and develop the technology required. This would likely be a cleaner, more efficient way than directly funding the mission through a space agency. The country in question (in this case USA) would offer the prize at tax-payer expense, but the benefits to jobs and the economy would be huge, not to mention furthering science, and if no one succeeds, the tax-payer doesn’t cough up a cent.
One idea that came out of TCFM was to ‘sell’ blocks of land on Mars (of which there is 144 million square kilometres), just as tracts of land in Kentucky were sold for large sums of money a hundred years before settlers arrived. This would encourage the exploration of Mars as investors push for development of the planet in the hope that the value of their Martian territory increases in value as miners look to lease the land and property developers look to purchase it in the future. This would require the creation of some international body whereby all countries agree on the legality and authority of individuals owning parts of Mars. Why not go one step further and use the money raised to just fund a Mars mission? Zubrin thinks it should only cost $4-6 million for a private entity. At a value of just $20 an acre (around 4,000 square metres), Mars would be worth $700 billion. Or you could, I don’t know, solve a whole bunch of problems. Whatever. While we’re at it lets start selling off other planets, moons, asteroids, stars… We could have a whole swatch of money from cashed up investors to do with what we like. Cash which probably would not have been spent anyway.
The concept of terraforming Mars is certainly plausible enough. Essentially, the theory is that there is carbon dioxide and other gas locked in the polar ice caps and beneath the surface in permafrost. The aim is to heat up a small area of an ice cap using one of several methods (my favourite is a giant mirror near Mars to reflect and focus sunlight – read TCFM for more details!), which releases some of the gas, thickening the atmosphere and trapping in more heat. Eventually enough gas is released that this triggers a ‘runaway’ effect which finishes melting the rest of the ice itself over a time scale of decades to centuries, eventually making the atmospheric pressure high enough to wander about without a full space suit. The air still won’t be breathable though, so then we’d have to introduce plants to turn some of the carbon dioxide into oxygen.
While I confess I don’t fully grasp some of the atmospheric and climate system modelling covered in TCFM, we have certainly achieved a version of ‘terraforming’ by accident here on Earth over the course of the industrial revolution, raising the carbon dioxide concentration from 280 to 400 parts per million (0.028-0.04%) and increasing surface temperature. Imagine what we could do when we actually try to achieve such changes. This brings me to an important question: should we terraform another planet?
It’s a difficult one to answer, and I don’t pretend to know the answer, but there are a lot of clever people working on this sort of thing, and I’m sure I’ll write a blog entry devoted to terraforming in the future.
Regarding the simpler case of accidentally transporting Earth-based microbes to Mars and ‘contaminating’ the planet, Zubrin raises the interesting point that unsterilized Earth originating material is already raining down on Mars, possibly seeded with organisms, just as Mars rock rains down on Earth (at the rate of around 500 kg per year) as the result of material flung into space from asteroid impacts and large volcanic eruptions. Following on from this is the realisation that perhaps life on Earth originated on Mars.
Zubrin appeals to our humanity in that we as humans have a need to explore the next frontier, and Mars is just that.
“One world will be just too small a domain to allow the preservation and continued generation of the diversity needed not just to keep life interesting, but to assure the survival of the human race.”
I wonder… does Zubrin refer to the innate human need to expand and consume more resources? If that is truly necessary for human survival as a species, we will eventually consume our entire Solar system in the not too distant future. Rocky planets, asteroids and gas giants alike will one by one fall to humanity’s conquest. Is it impossible for us as a species to be sustainable? Zubrin seems to think that humanity is not doomed because the universe is vast, its resources are infinite, and technology is advancing at an ever increasing rate. I’ll leave you all with that thought, and some of my favourite quotes from the The Case for Mars.
“To summarize in Star Trek terminology, what a piloted Mars mission needs are two “Scottys” and two “Spocks”. No “Kirks,” “Sulus,” or “McCoys” are needed…“
“Just as the example of nineteenth-century America changed the way the common man was regarded and treated in Europe, so the impact of progressive Martian social conditions may be felt on Earth as well as on Mars.”
Until next time.
Anyone interested in reading more about or joining the Mars Society can do so here: www.marssociety.org
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