Author Archives: Dan

The perils of planetary exploration

Artist's depiction of terraforming Mars. []

Artist’s depiction of terraforming Mars. []

I’m frequently concerned with the balance between scientific progress and the health and well-being of our species and our environment. These things do not necessarily go hand in hand, but neither are they absolutely opposed. One of the fundamental elements of technological advance is that it provides us with more options than we had before, and the way forward is often not entirely clear. Any decisions we make involve trade-offs between different values.

I’ve been reading the book “Cradle to Cradle”, by architect William McDonough and chemist Michael Braungart, which addresses the issue of sustainable design. In general it draws into question the “Reduce, Reuse, Recycle” motto of many sustainability advocates, suggesting that this approach delays the depletion of the earth’s resources rather than really trying to design products and lifestyles that are completely waste-free. They also have some things to say about space exploration:

There is some talk in science and popular culture about colonizing other planets, such as Mars or the moon. Part of this is just human nature: we are curious, exploring creatures. The idea of taming a new frontier has a compelling, even romantic, pull, like that of the moon itself. But the idea also provides rationalization for destruction, an expression of our hope that we’ll find a way to save ourselves if we trash our planet. To this speculation, we would respond: If you want the Mars experience, go to Chile and live in a typical copper mine. There are no animals, the landscape is hostile to humans, and it would be a tremendous challenge. Or, for a moonlike effect, go to the nickel mines of Ontario.

Seriously, humans evolved on the Earth, and we are meant to be here. Its atmosphere, its nutrients, its natural cycles, and our own biological systems evolved together and support us here, now. Humans were simply not designed by evolution for lunar conditions. So while we recognize the great scientific value of space exploration and the exciting potential of new discovery there, and while we applaud technological innovations that enable humans to “boldly go where no man has gone before,” we caution: Let’s not make a big mess here and go somewhere less hospitable even if we figure out how. Let’s use our ingenuity to stay here; to become, once again, native to this planet.

There are lot of beliefs inherent in that passage. Their complaint, that finding resources external to our planet makes us less likely to preserve those found on it, is one that I’ve heard before. It has some merit, in that sustainability has a strong economic imperative only when resources are limited. And although there are stronger arguments for sustainability than economics, that argument is often the strongest one for those making the decisions. So the pursuit of extraterrestrial resources (on Mars, as they suggest, or perhaps via asteroids) requires some caution, but the push for planetary exploration is so strong that in order to preserve the environments on Earth we need to rely on other arguments.

I don’t think the authors put enough stock in the scientific value of planetary exploration, nor do they give enough credit to the incredible curiosity and adaptability of people. For millennia, here on earth, people have been pushing to places they had no good reason to be. Sometimes it has been for the pursuit of resources, and sometimes it has been just to see what’s there.  Exploration is a fundamental characteristic of humanity. They contend that we “evolved on the Earth, and we are meant to be here,” but by that logic nobody would have ventured to new continents, establishing themselves in a new life there. Humanity evolved in Africa, but we didn’t stay confined there. Human evolution has virtually stopped, but we are now in a process of human/technology co-evolution. This has carried people from their homelands across oceans, to the barren plains of Antarctica, to the depths of the ocean, and it will carry us beyond this planet. It is true that we evolved on Earth, but we also involved in the Solar System, in the Milky Way, in the Universe.

Earth should and will hold a special place for humanity, but for future explorers it may be the same way that a modern American can trace his or her roots back to Africa, Asia, or Europe. Those places are a part of our history, part of our identity, but no longer our home. Humans on Mars will be Martians, and they may be concerned with preserving the wilderness of that planet. That doesn’t change the fact that those of us remaining on Earth still live here, and as long as we do its preservation should be a top concern, not because of the flimsy and variable problem of resource availability, but because it is our home.

Mapbox Mars

Mapbox, a company specializing in producing and maintaining detailed online maps, has recently released two map versions of the surface of Mars. Mars Satellite contains satellite imagery of the martian surface, while Mars Terrain is a vectorized version. Both are pretty cool, and it’s interesting to think that the surface of another planet is becoming so well known. Check it out. 

Student controlled satellite sensors

I’ve been hearing about a number of interesting science/tech education projects recently, all approaching the topic in innovative and very hands-on ways. Just recently I met someone working for a new startup called Ardusat, which provides students with the opportunity to program and operate Arduino microcontrollers aboard satellites. These microcontrollers are connected to a variety of sensors, allowing students to design experiments and collect a variety of data. Here we are, barely 50 years after the launch of Sputnik, and space has become a laboratory accessible from the classroom. 

Cycle for Science

On April 17th Rachel and Elizabeth, two young scientists and cyclists, left San Francisco on bicycles and set out for the east coast in what they call Cycle for Science. Along the way they talked with educators and classrooms about what science is and how everyone can participate. I’m a little sad that I only just heard about the trip, now that it is almost over, but it is nevertheless an interesting project, and I’m sure there will be good educational material that comes out of it.

100,000 Stars

100,000 Stars is an online visualization of our solar system’s nearest neighboring stars. It was created by Google’s Data Arts Team (see a write-up of the project here). Although it is perhaps a bit difficult to extract specific useful information from this site, it provides an interesting perspective on our place in the universe, a self-portrait of our galaxy (or at least some subset of it) that could only be possible with a computer visualization.

Our Island Universe

The idea that there are galaxies that surround us, and that they stretch out to the edge of the universe, is a relatively new one in the historical context. It is an idea that was perhaps first suggested by the philosopher Immanuel Kant, who proposed that certain nebula (cloudy smudges of light) seen in telescopes were outside of our own local sphere of space and existed in their own right as what he called ‘island universes.’ The resolution of this issue would have to wait until the beginning of the 20th century, when new astronomical observations brought, quite literally, new light to the discussion.

The nature of these nebula was the subject of a serious discussion that took place at the meeting of the National Academy of Sciences in 1920, an event now known as the Great Debate. On one side of the debate was Harlow Shapley, who argued that the nebula were contained within our own local area and that the Milky Way encompassed the entirety of the universe. Arguing against this was Heber Curtis, who proposed that the number of nova observed within the Andromeda nebula indicated that it was an entirely separate galaxy from our own.

One of the definitive pieces of evidence in favor of the ‘island universe’ hypothesis came in 1924, when Edwin Hubble (the namesake of the famous space telescope) published his observation of Cepheid variables (a certain class of star known to have specific relationships between brightness, fluctuation period, and distance) in the Andromeda nebula, establishing it at a distance on the order of a million light years, well beyond the acknowledged limits of the Milky Way. Andromeda was not a mere nebula, but an entire galaxy.

These results build on earlier work by Shapley, who had undertaken a mapping of the Milky Way and found that the Sun occupied an unremarkable location towards the edge. Just as Shapley’s work had displaced mankind from the center of our own galaxy and reinforced the possibility that our own solar system was one of many contained within that galaxy, Hubble’s results now suggested that even our galaxy was only one of many.

Hubble Ultra Deep Field

The Hubble Ultra Deep Field image, taken by the Hubble telescope and released in 2004. This image covers as much of the sky as a 1mm by 1mm square held at arm’s length and contains an estimated 10,000 galaxies. Image Source:      Image Author: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)

Shapley recognized the implications of this continued progression. He remarked,
“The physical universe was anthropocentric to primitive man. At a subsequent stage of intellectual progress it was centered in a restricted area on the surface of the earth. Still later, Ptolemy and his school, the universe was geocentric; but since the time of Copernicus the Sun, as the dominating body of the solar system, has been considered to be at or near the center of the stellar realm. With the origin of each of these successive conceptions, the system of stars has ever appeared larger that was thought before. Thus the significance of man and the earth in the sidereal scheme has dwindled with advancing knowledge of the physical world, and our conception of the dimensions of the discernible stellar universe has progressively changed.”

As Shapley found, both in his own work and in the history of scientific progress that came before him, the more knowledge that we gain about the way that the universe works, the further from the center of things we move, and the more apparent it becomes that we occupy a small place in the cosmos. And yet, as conscious minds, our small place is a very special place. As Carl Sagan remarked, “we are a way for the cosmos to know itself.”  Perhaps we may discover other life out in the universe somewhere, potentially even conscious, intelligent life. As enormous as the universe is, anywhere that conscious life arises is itself a very remarkable place.

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