An Early Manned Mission to Mars in 2018?

On 27 February Dennis Tito, who paid his way to the ISS as a tourist back in 2001, will be announcing the plans of a new private space company, the Inspiration Mars Foundation.  The rumor mill has it that their purpose is to launch a manned expedition to Mars as early as January 2018. 

According to several sources, the mission would be a 501-day free-flying flyby (neither orbiting nor landing on Mars).  It would be lifted into space by a Falcon Heavy launch vehicle and with crew accommodation for two people in the form of a modified Dragon capsule, of recent ISS fame.  This scheme would incorporate ideas already put forward by SpaceX’s Elon Musk, who is a vocal advocate of both private space development and the exploration and eventual colonization of Mars.

The mission would be financed privately and would advance on a much more ambitious schedule than any governmental or intergovernmental project could reasonably expect to achieve.

For those who instinctively disbelieve the concept that private enterprise can provide access to space cheaper and on a larger scale than governmental entities can, a refresher course on SpaceShipTwo, the Bigelow inflatable space station module, the Dragon capsule, and the dozens of companies that have set their sights on providing low-cost private access to space would be in order.

This seems to be a typically American thrust, but in fact Canadian, European, and other companies are also engaged in these pursuits.  In fiction, the first manned mission to the Moon was envisioned by Jules Verne (De la Terre a la Lune; 1865) as being a private venture funded by rich American industrialists, building on Civil War military technology, and launched (fired!) from Florida by a giant gun.  In fact, strangely enough, the first technically plausible suggestion of how to get humans into space was in a novel, “Beyond the Planet Earth: In the Year 2000”, written by the pre-Soviet Russian visionary Konstantin Tsiolkovskii in 1916.  In it, the impetus for the development of manned spaceflight came from an international team of scientists and a group of private investors whom we would now call venture capitalists.

Travel to Mars (“Barsoom”) was a standard theme of the writings of Edgar Rice Burroughs.  Percy Gregg’s novel “Across the Zodiac” (1880) recounts a visit to Mars.  Another early tale of interplanetary travel, like Tsiolkovskii’s novel also set in the year 2000,  was “A Journey in Other Worlds”, authored in 1894 by John Jacob Astor IV.  These and many other books, such as E. E. “Doc” Smith’s novels, generally attribute space travel ventures to innovators and private individual, not governments.

Perhaps Dennis Tito’s announcement will bring that spirit of non-governmental initiative not just into space, but all the way to Mars.

Curiosity about Life on Mars

The Curiosity rover is preparing to drill a little hole in a slab of Martian sedimentary rock to extract material for testing in the ongoing search for life on the red planet.  What can we expect to find?  What was the environment like for the origin and evolution of life forms on Mars?

               We know far more about the present physical and chemical conditions on the surface of Mars than we know about the distant, presumably warmer and wetter, past.  Since Mars has a thin, very dry atmosphere of 97% pure carbon dioxide, ultraviolet (UV) light from the Sun readily penetrates to the surface.  In the absence of more than a tiny trace of oxygen, ozone cannot be made in quantity, and cannot provide an ozone layer similar to Earth’s to protect the surface from killing UV radiation.  In fact, UV light can dissociate carbon dioxide into carbon monoxide (CO) and atomic oxygen (O) even at the surface of the planet.  Even a tiny trace of atomic oxygen is very bad news for organic matter: O is a very powerful oxidizing agent.  Any organic matter exposed at the surface of Mars, whether exposed by weathering of ancient organic-bearing sediments or dropped onto Mars by impacts of carbonaceous meteorites, would quickly ”burn” into carbon dioxide and water vapor.  It is only in the interiors of ancient sedimentary rocks, where O cannot penetrate, that organic matter might survive. 

               The CO₂ content of the atmosphere of Mars is sufficient to provide an average pressure of about 0.006 atmospheres at the surface, although this number is very variable from place to place because of the wide range of elevations spanning a deep basin (Hellas) and several towering volcanoes.  The CO₂ famous for maintaining Earth’s surface temperature above the freezing point (via the greenhouse effect) has a surface pressure of less than 0.0004 atmospheres.  So why is Mars so cold?  Several reasons: the greenhouse effect on Earth is dominated by water vapor, which is very rare on Mars; Mars experiences about half the intensity of sunlight that Earth receives.  So an earlier, warmer Mars requires that it was also a wetter Mars.  You need water vapor to make Mars warm enough to have water vapor!   Given favorable early conditions on Mars, with liquid water present and a strong greenhouse effect at work, life may indeed have originated there.  But what evidence of that former life would we be able to find today?  There are two obvious possibilities: well-protected organic matter deep inside ancient sedimentary rocks, or fossils of simple life forms.  But evidence of ancient life would not necessarily prove an independent origin for life off Earth: large impact events can launch surface rocks from both Earth and Mars into orbits around the Sun, from which they can collide with and land on either planet.  Martian life, if any, may be expatriate Earth life--- and vice versa.

"Demandite" and Resources in Space

“Demandite” is the word used by mineral economists to describe the materials that must be provided-- usually by mining-- to meet the needs of civilization. In the usual terrestrial setting, air and water are assumed to be freely available, and fossil fuel (natural gas, crude oil, and coal) is considered a necessity. In space, where dependence on solar energy is the norm, and where air and water must be “mined”, the numbers are different. The proportions of mineral needs, however, are otherwise generally similar. You can then ask how much of each material (iron, carbon, nitrogen, aluminum, copper, oxygen, water, nitrogen, etc.) is needed to be in circulation to support one person, depending on “renewable” (inexhaustible) solar energy to drive industry, agriculture, and recycling. We can then compare those requirements to the natural resources available on bodies in nearby space, and calculate how many people could be supported at each of those locations.


The proportions of these necessary materials (the relative abundances of water and iron, for example) are very different on the Moon, Mars, and nearby asteroids. The Moon, for example, is severely deficient in all volatile elements, including carbon, nitrogen, hydrogen, and chlorine, Mars, with its tenuous atmosphere and widespread ice deposits, fares better. But best by far is the match between the composition of near-Earth asteroids (NEAs) and “space-based demandite”. The 1000 or so kilometer-sized near-Earth asteroids contain enough of every essential element to support a population of 10 billion people from now until the Sun dies of old age. The NEAs, however, are a renewable resource: in nature, the rate at which NEAs are lost by collision with planets and ejection from the Solar System is compensated by recruitment of fresh asteroids kicked into near-Earth space by Jupiter’s gravitational interactions.

But what about the main Asteroid Belt? The answer is startling: the Belt contains one million times as much mass as the entire NEA population. Again depending on the Sun for power, the Belt could support a population of 10 million billion people-- a million times the ultimate carrying capacity of Earth. With that many people, wouldn’t we be running out of solar power? Not really-- even under these extreme assumptions, we would require less than one millionth of the Sun’s output energy.

The non-renewable resources available to Earth-bound humanity are finite. The resources available to a space-faring humanity are effectively infinite.