Lichen Growing on an Arizona Boulder
Yes, what you have heard about Southern Arizona is true. It gets warm here in the desert. For most of July it is well over 100 degrees, and the humidly is usually less than 20%. It starts cooling off in September and October when the monsoon rains come. It is a hostile environment, but plants and animals have learned to adapt. For me — a kid who grew up in grey drizzly Oregon — it is like a huge exotic petting zoo. I love it, and spend all the time I can enjoying it.
A few years ago, I was coming down the Tanque Verde Trail in the Rincon Mountains outside of Tucson when I came across an odd-looking boulder. We have many boulders here, but this one caught my eye because of an odd colored streak running along one side. It was sort of purple. At first, I thought it was a streak of copper ore — we have, a lot of copper here — but copper is usually a turquoise color and what I was looking at was definitely purple. It was so unusual I took some photographs thinking I would search the net or ask a geologist about it.
I was about half way down the mountain when I ran into a group of about a dozen young men and women along the trail. They were huddled together in several small groups, heads together and murmuring as they examined rock outcroppings with the same strange streaks, I saw on the rock further up the trail.
I joined one of the knots of people. “What the heck is that anyway?” I asked pointing to a streak in the rock they were examining. “I found a big rock up the trail with the same streaks.”
“Oh that’s lichens.”
“Lichens? Like moss?”
Suddenly I got very interested.
Being from Oregon I knew all about moss. It is green, fuzzy, and filled with water. It is slimy to the touch and slippery underfoot. When I was a kid, my father once volunteered me to spend the weekend helping an elderly friend collect Sphagnum Moss from his Tillamook County swamp for local florists.
“How can lichens grow on rocks here? Its 115 degrees today and probably 15% humidity.”
A woman stepped forward, introduced herself, and told me that she was supervising this group of PhDs, post-grads, and graduate students on this field trip to see lichens in their natural habitat and take samples for the lab.
The kinds of lichens these scientists study are called “extremophiles” because they can live in such hostile conditions. Not very long ago, it was a scientific fact that biological organisms could survive only in environments that were relatively mild; say between the freezing and boiling point of water.
However, little by little, as more advanced instruments became available scientists found microbes where they should not have existed. At first in highly acidic water near volcanos, then in the superheated and highly pressurized waters of geysers like Old Faithful. Microbes are living deep beneath the earth in rocks where no light shines.
In his Can’t.Put.It.Down book all about dirt, Tales from the Underground, David Wolfe takes us into the world beneath our feet. He tells us about a 1989 filed trip Princeton geologists and biologists took to South Africa’s Driefontein gold mine to look for suspected extremophiles. At a depth of two miles in 140 degree temperatures and until recently under extreme pressure the scientists took samples of living microbes from the rock that had been exposed by the miners.
Their analysis showed that there were a number of species of extremophiles living in a symbiotic relationship with one another. Living in an oxygen free environment some microbes evolved to breathe iron oxide, (rust), while others exhaled methane. An entire colony of these creatures were living in solid rock under high pressure, high heat, with no light or water.
Scientists love to talk about their work with people who have some inkling of what they study, and the group of lichen scientists on the Tanque Verde trail loosened up a bit. They showed me how to tell different species of lichen by the color and location. Some lichens need just a little sunlight and were easy to see on the rock outcroppings. Others preferred cooler and darker fissures.
Suddenly I knew exactly why they were there.
“Do you guys know about a new company called Planetary Resources?”
Abruptly all conversation stopped and everyone was looking at me. The fate of Old West claim jumpers sprang to mind and I found myself regretting my mention of Planetary Resources. We were miles from the nearest road and the desert can feel very empty sometimes.
“What do you know about it?” someone said.
I spit out what I knew like a tickertape:
“It’s a newly formed company funded by the founders of Google, partnering with Virgin Galactic with plans to lasso an asteroid, tow it into lunar-earth orbit and mine and smelt it for precious metals on site and transport them to earth.”
“How do you know that?”
“Uh, I read a lot.”
For just a heartbeat, it was dead silent.
Then they all started laughing.
“Lasso an asteroid?”
“Only in Arizona!”
“Can’t wait to put that one in a paper.”
Academics can be a competitive bunch, but now they seemed to understand that I was not a scholarly spy looking for the secrets of their research, like a scene out of Indiana Jones. In fact, they shared their excitement about their research.
That is because I understood they are onto something incredibly momentous, something of enormous historical, scientific and economic importance.
The goal of Planetary Resources and their competitors is as I described — towing an asteroid into earth orbit, and using genetically modified extremophiles to eat and excrete everything needed to mine gold, platinum, and most importantly, water, from an asteroid.
Yes, asteroids have water. Lots of it. It happens that space is full of water.
Rare Earth is a wonderful tour through the evolution of the solar system. Anyone with a passing interest in the birth and life of our planetary home should give this book a read. The physics and chemistry can be a little challenging for someone not well steeped in undergraduate STEM courses, so it takes careful reading in places. However, Peter Ward and Don Brownlee do an excellent job of making complex science understandable for the rest of us.
Following the Big Bang there was no solid surface anywhere, just elements slowly accreting into molecules in the heat and darkness. As solids formed these molecules coalesced into solid bodies, like comets, asteroids and embryonic planets. These bodies contained large amounts of water, or perhaps their constituent elements, hydrogen and oxygen.
Ward and Brownlee paint a vibrant picture of early Earth as watery asteroids and comments pummeled its surface. For half a billion years this went on, slowing to a top 3.8 billion years ago. Scientists think this is how Earth got its water, although some was already in the elements that formed the earth.
Planetary Resources’ business plan seems to be to use the precious metals extracted from an asteroid to fund efficient means of harvesting water to use as fuel. There would be little need to bring asteroids to earth after the first one. Instead, specific asteroids in specific locations could be targets for genetically modified microbes from earth. They would live and grow on asteroids, producing water for passing spaceships to use as fuel.
We are talking about cornering the market on interplanetary fueling stations.
Standard Oil of the late 21st century!
If that that sounds far-fetched, so might this:
There were very few roads suitable for automobiles in 1900. By 1916, there were 521,915 miles of surfaced roads. The event that caused this explosion of paving was the other explosion of automobile production. Only about 1,000 cars were built in 1899. They were curious contraptions of little practical value. However, by 1917 auto productions passed the one million mark.
That is not the half of it.
Consider what was needed to accommodate that sort of growth. Oil refineries, concrete and asphalt production, rail lines and rolling stock connecting manufactures, suppliers, extraction industries, to just scratch the surface. All these technologies were brand new at that time, and represented the cutting edge of chemistry, physics, metallurgy, and organizational theory.
At the same time, similar transformations were occurring in the electrification of the United States and our educational system. The Industrial Economy was nearing its peak.
All in the space of just 25 years or so.
Towing asteroids into lunar-earth orbit is no more far-fetched that what has already happened in the recent past.
Asteroid mining might just be what allows us to build a space-based economy. Maybe that is the economy we are fated to build and our current economic morass is an interlude separating a 19th century industrial economy and a 21st century space based economy. Imagine being alive to see the end of one and the beginning of another as humanity begins the transition to a space faring race.
What a momentous time to be alive!
If you liked this article here are some books and news items you might also enjoy:
Ward, P. D., & Brownlee, D. (2000). Rare earth: Why complex life is uncommon in the universe. New York: Copernicus
Wolfe, D. W. (2002). Tales from the underground: A natural history of subterranean life. Cambridge, MA: Perseus Pub.