Claude Plymate is the Telescope Engineer/Chief Observer at Big Bear Solar Observatory in California, and is the former chief wrangler of the McMath-Pierce Solar Telescope at Kitt Peak National Observatory Arizona for many years. He is a regular contributor to Musical Milliner.
It likely won’t come as any surprise to those of you who know me or have read some of my earlier essays that I am a strong advocate of sending humans to Mars. What might surprise you are my reasons which are more about societal needs than about scientific exploration. Our population has now passed the 7 billion mark.
There are indicators all around us that this planet cannot maintain the pressure we’re applying to its resources and resiliency. There is little reason for me to go into the details here; you are all well aware of the risks we are subjecting ourselves to. Global climate change, fresh water depletion, famine, nuclear proliferation, pandemics and war are just a sampling of the dangers we pose to ourselves. On top of our self-imposed hazards, the solar system is in general a menacing place to live. Asteroid impacts have already wiped out the dominant species on Earth at least once before. A nearby supernova could disrupt our ozone layer with catastrophic consequences. We are fortunate to have a strong magnetic field and atmosphere that protects us from the harsh radiation coming from solar flares but civilization has left our technology quite vulnerable to such eruptions. It doesn’t appear that a “super flare” will kill us outright but just imagine the disruption to society if the Internet, electric grid, GPS system, radio communications and even telephones suddenly and unexpectedly went ‘dark’– and not just for a few hours but possibly days, weeks or even months!
What I’m trying to point out is that there are many real threats to our civilization and even our existence as a species. Some are self-imposed, some are natural.
This leads us to the question of how to mitigate such threats to humanity. Consider how you deal daily with risk management of other items you regard as valuable. For example, you wish to protect your documents and photos stored on your computer’s hard drive. What do you do? Of course, you backup your files onto a separate drive stored in a separate location. (You do back up your files, don’t you?) Applying this same rationale to society naturally leads to the conclusion that to survive long-term, humanity must expand beyond this one little planet. Then, even if the unthinkable occurs, all that humanity has achieved won’t completely disappear from history.
The obvious first destination for a human outpost beyond Earth is Mars. Mars is the most Earthlike of the other planets within the solar system. It is close in astronomical terms and has an atmosphere. Mars is a place we can live. Plus, the lower surface gravity of Mars (about 1/4 that of Earth) makes getting on and off its surface much easier than here on the Earth.
Unfortunately, the atmosphere on Mars is very tenuous with a mean surface pressure ~ 600 Pa (0.087 psi), equivalent to an Earth atmospheric altitude of around 90,590 ft (27,612 m). On top of that, it’s a toxic mixture of mostly carbon dioxide. Anyone on the surface would have to wear a pressure suit (space suit). Even this exceedingly thin atmosphere could be used to pressurize suits & shelters. All that would be needed would be a compressor to pressurize the interiors. Simple inflatable structures could even be used for such things as storage, workshops and greenhouses. You still couldn’t breathe in the high CO2 environments but an oxygen mask would be all that’s required for people to work in otherwise shirtsleeve comfort. There are likely many plants that could thrive in these pressurized greenhouses. Obliviously, living quarters would need more oxygen to make a breathable atmosphere which is easily attainable
by liberating O2 from either CO2, water or even iron oxides (rust!) in the soil that gives the planet its red color.
Water means life. We need water to drink, water for crops and water to make oxygen. Recent Mars probes are making it clear that water (at least in the form of ice) is much more common on Mars than previously believed. What is required to harvest the water is energy; energy to drill wells or mine ice, energy to extract the O2. Possible sources for power include solar panels and/or nuclear generators and perhaps even geothermal. I suspect that the atmosphere is simply too thin to support wind power.
There are two primary arguments against going to Mars that people normally state; interplanetary spaceflight is beyond our technical ability and the cost would be far too great. I’d like to address these arguments one at a time.
Stay tuned for We Should Become Martians: Part II next week.