Speculative Mineralogy

[Image: An otherwise unrelated image of crystal twinning, via Geology IN].

It’s hard to resist a headline like this: writing for Nature, Shannon Hall takes us inside “the labs that forge distant planets here on Earth.”

This is the world of exogeology—the geology of other planets—“a research area that is bringing astronomers, planetary scientists and geologists together to explore what exoplanets might look like, geologically speaking. For many scientists, exogeology is a natural extension of the quest to identify worlds that could support life.”

To understand how other planets are made, exogeologists are synthesizing those planets in miniature in the earthbound equipment in their labs. Think of it as an extreme example of landscape modeling. “To gather information to feed these models,” Hall writes, “geologists are starting to subject synthetic rocks to high temperatures and pressures to replicate an exoplanet’s innards.”

Briefly, it’s easy to imagine an interesting jewelry line—or architectural materials firm—using fragments of exoplanets in their work, crystals grown as representations of other worlds embedded in your garden pavement. Or fuse the ashes of your loved ones with fragments of hypothetical exoplanets. “Infinite memorialization,” indeed.

In any case, recall that, back in 2015, geologist Robert Hazen “predict[ed] that Earth has more than 1,500 undiscovered minerals and that the exact mineral diversity of our planet is unique and could not be duplicated anywhere in the cosmos.” As Hazen claimed, “Earth’s mineralogy is unique in the cosmos.” If we are, indeed, living in mineralogically unique circumstances, then this would put an end to the fantasy of finding a geologically “Earth-like” planet. But the search goes on.

This is not the only example of producing hypothetical mineral models of other worlds. In 2014, for example, ScienceDaily reported that “scientists for the first time have experimentally re-created the conditions that exist deep inside giant planets, such as Jupiter, Uranus and many of the planets recently discovered outside our solar system.” Incredibly, this included compressing diamond to a concentration denser than lead, using a giant laser.

Other worlds, produced here on Earth. Exoplanetary superdiamonds.

Read more over at Nature.

(Nature article spotted via Nathalia Holt).

Planetary Scale

[Image: “CHRONOS: The Space-Time Planetarium,” proposed by Drew Heller, Isabella Marcotulli, and Ibrahim Salman, via Eleven Magazine].

With news of “the largest planetarium in the Western Hemisphere and the fourth largest in the world” opening in New Jersey, I’m reminded of a design competition I meant to post about earlier this year.

A few months ago, Eleven Magazine hosted a quick competition to rethink the planetarium. It’s a great design brief: Eleven’s editors asked “if architecture itself could become—once again—a tool for experiencing and understanding space. How can architecture engage with and enhance today’s renewed age of space exploration and discovery? What does the next generation of planetariums look like?”

You can click around on the various entries here, but a few seemed worth mentioning.

[Image: “Microsphere” planetarium proposal by Christian Gabbiani and Elisa Porro, via Eleven Magazine].

The “Microsphere” proposal, for example, entails “a network of little planetariums scattered all over the world.” As the title suggests, each planetarium would be a small, single-occupancy sphere acting as a meditative space for viewing, studying, or thinking about the cosmos.

It’s an idea that only suffers from the unnecessary stipulation that these should be built directly next to existing, often very ancient sites of star observation, including Stonehenge. Not only does Stonehenge not need this sort of thing parked next to it, but installing these out in the suburbs, on city streets, on the roofs of low-income housing units, or even hidden in thickets in state parks would seem to be a much more interesting way for these structures to bring astronomy to the masses.

[Image: “Microsphere” planetarium proposal by Christian Gabbiani and Elisa Porro, via Eleven Magazine].

Another project is interesting for its attempt to reconceive what “space” really is and how a planetarium is meant to represent or engage with it.

[Image: “CHRONOS: The Space-Time Planetarium,” proposed by Drew Heller, Isabella Marcotulli, and Ibrahim Salman, via Eleven Magazine].

Acting as a “space-time planetarium,” a project called CHRONOS would allow visitors to “perceive astronomical scenes at different rates… through a labyrinth of six architectural techniques that invite the user to abandon earthly notions of space and time.”

The building thus requires a “space-time diagram.”

[Image: “Microsphere” planetarium proposal by Christian Gabbiani and Elisa Porro, via Eleven Magazine].

Whether or not the resulting building would actually resemble what the designers have proposed here, it sounds awesome. “The planetarium grounds users through abstract learning as they navigate the entanglement while warping their perception of space-time,” they write. “While traveling through a series of architectural space-time scenarios, users are enlightened with astronomical scenes that transcend human perception.”

[Image: “Microsphere” planetarium proposal by Christian Gabbiani and Elisa Porro, via Eleven Magazine].

As you’d expect, not every entry is particularly interesting and there are some real doozies in there, but it’s worth checking out. While you’re there, though, check out the other competitions—some still ongoing—that Eleven has hosted.

The Coming Amnesia

[Image: Galaxy M101; full image credits].

In a talk delivered in Amsterdam a few years ago, science fiction writer Alastair Reynolds outlined an unnerving future scenario for the universe, something he had also recently used as the premise of a short story (collected here).

As the universe expands over hundreds of billions of years, Reynolds explained, there will be a point, in the very far future, at which all galaxies will be so far apart that they will no longer be visible from one another.

Upon reaching that moment, it will no longer be possible to understand the universe’s history—or perhaps even that it had one—as all evidence of a broader cosmos outside of one’s own galaxy will have forever disappeared. Cosmology itself will be impossible.

In such a radically expanded future universe, Reynolds continued, some of the most basic insights offered by today’s astronomy will be unavailable. After all, he points out, “you can’t measure the redshift of galaxies if you can’t see galaxies. And if you can’t see galaxies, how do you even know that the universe is expanding? How would you ever determine that the universe had had an origin?”

There would be no reason to theorize that other galaxies had ever existed in the first place. The universe, in effect, will have disappeared over its own horizon, into a state of irreversible amnesia.

[Image: The Tarantula Nebula, photographed by the Hubble Space Telescope, via the New York Times].

It was an interesting talk that I had the pleasure to catch in person, and, for those interested, it includes Reynolds’s explanation of how he shaped this idea into a short story.

More to the point, however, Reynolds was originally inspired by an article published in Scientific American back in 2008 called “The End of Cosmology?” by Lawrence M. Krauss and Robert J. Scherrer.

That article’s sub-head suggests what’s at stake: “An accelerating universe,” we read, “wipes out traces of its own origins.”

[Image: A “Wolf–Rayet star… in the constellation of Carina (The Keel),” photographed by the Hubble Space Telescope].

As Krauss and Scherrer point out in their provocative essay, “We may be living in the only epoch in the history of the universe when scientists can achieve an accurate understanding of the true nature of the universe.”

“What will the scientists of the future see as they peer into the skies 100 billion years from now?” they ask. “Without telescopes, they will see pretty much what we see today: the stars of our galaxy… The big difference will occur when these future scientists build telescopes capable of detecting galaxies outside our own. They won’t see any! The nearby galaxies will have merged with the Milky Way to form one large galaxy, and essentially all the other galaxies will be long gone, having escaped beyond the event horizon.”

This won’t only mean fewer luminous objects to see in space; it will mean that, “as a result, Hubble’s crucial discovery of the expanding universe will become irreproducible.”

[Image: The “interacting galaxies” of Arp 273, photographed by the Hubble Space Telescope, via the New York Times].

The authors go on to explain that even the chemical composition of this future universe will no longer allow for its history to be deduced, including the Big Bang.

“Astronomers and physicists who develop an understanding of nuclear physics,” they write, “will correctly conclude that stars burn nuclear fuel. If they then conclude (incorrectly) that all the helium they observe was produced in earlier generations of stars, they will be able to place an upper limit on the age of the universe. These scientists will thus correctly infer that their galactic universe is not eternal but has a finite age. Yet the origin of the matter they observe will remain shrouded in mystery.”

In other words, essentially no observational tool available to future astronomers will lead to an accurate understanding of the universe’s origins. The authors call this an “apocalypse of knowledge.”

[Image: “The Christianized constellation St. Sylvester (a.k.a. Bootes), from the 1627 edition of Schiller’s Coelum Stellatum Christianum.” Image (and caption) from Star Maps: History, Artistry, and Cartography by Nick Kanas].

There are many interesting things here, including the somewhat existentially horrifying possibility that any intelligent creatures alive in that distant era will have no way to know what is happening to them, where things came from, even where they currently are (an empty space? a dream?), or why.

Informed cosmology will, by necessity, be replaced with religious speculation—with myths, poetry, and folklore.

[Image: 12th-century astrolabe; from Star Maps: History, Artistry, and Cartography by Nick Kanas].

It is worth asking, however briefly and with multiple grains of salt, if something similar has perhaps already occurred in the universe we think we know today—if something has not already disappeared beyond the horizon of cosmic amnesia—making even our most well-structured, observation-based theories obsolete. For example, could even the widely accepted conclusion that there was a Big Bang be just an ironic side-effect of having lost some other form of cosmic evidence that long ago slipped eternally away from view?

Remember that these future astronomers will not know anything is missing. They will merrily forge ahead with their own complicated, internally convincing new theories and tests. It is not out of the question, then, to ask if we might be in a similarly ignorant situation.

In any case, what kinds of future devices and instruments might be invented to measure or explore a cosmic scenario such as this? What explanations and narratives would such devices be trying to prove?

[Image: “Woodcut illustration depicting the 7th day of Creation, from a page of the 1493 Latin edition of Schedel’s Nuremberg Chronicle. Note the Aristotelian cosmological system that was used in the Middle Ages, below, with God and His retinue of angels looking down on His creation from above.” Image (and caption) from Star Maps: History, Artistry, and Cartography by Nick Kanas].

Science writer Sarah Scoles looked at this same dilemma last year for PBS, interviewing astronomer Avi Loeb.

Scoles was able to find a small glimmer of light in this infinite future darkness, however: Loeb believes that there might actually be a way out of this universal amnesia.

“The center of our galaxy keeps ejecting stars at high enough speeds that they can exit the galaxy,” Loeb says. The intense and dynamic gravity near the black hole ejects them into space, where they will glide away forever like radiating rocket ships. The same thing should happen a trillion years from now.

“These stars that leave the galaxy will be carried away by the same cosmic acceleration,” Loeb says. Future astronomers can monitor them as they depart. They will see stars leave, become alone in extragalactic space, and begin rushing faster and faster toward nothingness. It would look like magic. But if those future people dig into that strangeness, they will catch a glimpse of the true nature of the universe.

There might yet be hope for cosmological discovery, in the other words, encoded in the trajectories of these bizarre, fleeing stars.

[Images: (top) “An illustration of the Aristotelian/Ptolemaic cosmological system that was used in the Middle Ages, from the 1579 edition of Piccolomini’s De la Sfera del Mondo.” (bottom) “An illustration (influenced by Peurbach’s Theoricae Planetarum Novae) explaining the retrograde motion of an outer planet in the sky, from the 1647 Leiden edition of Sacrobosco’s De Sphaera.” Images and captions from Star Maps: History, Artistry, and Cartography by Nick Kanas].

There are at least two reasons why I have been thinking about this today. One was the publication of an article by Dennis Overbye earlier this week about the rate of the universe’s expansion.

“There is a crisis brewing in the cosmos,” Overbye writes, “or perhaps in the community of cosmologists. The universe seems to be expanding too fast, some astronomers say.”

Indeed, the universe might be more “virulent and controversial” than currently believed, he explains, caught-up in the long process of simply tearing itself apart.

[Image: A “starburst galaxy” photographed by the Hubble Space Telescope].

One implication of this finding, Overbye adds, “is that the most popular version of dark energy—known as the cosmological constant, invented by Einstein 100 years ago and then rejected as a blunder—might have to be replaced in the cosmological model by a more virulent and controversial form known as phantom energy, which could cause the universe to eventually expand so fast that even atoms would be torn apart in a Big Rip billions of years from now.”

In the process, perhaps the far-future dark ages envisioned by Krauss and Scherrer will thus arrive a billion or two years earlier than expected.

[Image: Engraving by Gustave Doré from The Divine Comedy by Dante Alighieri].

The second thing that made me think of this, however, was a short essay called “Dante in Orbit,” originally published in 1963, that a friend sent to me last night. It is about stars, constellations, and the possibility of determining astronomical time in The Divine Comedy.

In that paper, Frederick A. Stebbins writes that Dante “seems far removed from the space age; yet we find him concerned with problems of astronomy that had no practical importance until man went into orbit. He had occasion to deal with local time, elapsed time, and the International Date Line. His solutions appear to be correct.”

Stebbins goes on to describe “numerous astronomical references in [Dante’s] chief work, The Divine Comedy”—albeit doing so in a way that remains unconvincing. He suggests, for example, that Dante’s descriptions of constellations, sunrises, full moons, and more will allow an astute reader to measure exactly how much time was meant to have passed in his mythic story, and even that Dante himself had somehow been aware of differential, or relativistic, time differences between far-flung locations. (Recall, on the other hand, that Dante’s work has been discussed elsewhere for its possible insights into physics.)

[Image: Diagrams from “Dante in Orbit” (1963) by Frederick A. Stebbins].

But what’s interesting about this is not whether or not Stebbins was correct in his conclusions. What’s interesting is the very idea that a medieval cosmology might have been soft-wired, so to speak, into Dante’s poetic universe and that the stars and constellations he referred to would have had clear narrative significance for contemporary readers. It was part of their era’s shared understanding of how the world was structured.

Now, though, imagine some new Dante of a hundred billion years from now—some new Divine Comedy published in a trillion years—and how it might come to grips with the universal isolation and darkness of Krauss and Scherrer. What cycles of time might be perceived in the lonely, shining bulk of the Milky Way, a dying glow with no neighbor; what shared folklore about the growing darkness might be communicated to readers who don’t know, who cannot know, how incorrect their model of the cosmos truly is?

(Thanks to Wayne Chambliss for the Dante paper).

Alien Geology, Dreamed By Machines

[Image: Synthetic volcanoes modeled by Jeff Clune, from “Plug & Play Generative Networks,” via Nature].

Various teams of astronomers have been using “deep-learning neural networks” to generate realistic images of hypothetical stars and galaxies—but their work also implies that these same tools could work to model the surfaces of unknown planets. Alien geology as dreamed by machines.

The Square Kilometer Array in South Africa, for example, “will produce such vast amounts of data that its images will need to be compressed into low-noise but patchy data.” Compressing this data into readable imagery opens space for artificial intelligence to work: “Generative AI models will help to reconstruct and fill in blank parts of those data, producing the images of the sky that astronomers will examine.”

The results are thus not photographs, in other words; they are computer-generated models nonetheless considered scientifically valid for their potential insights into how regions of space are structured.

What interests me about this, though, is the fact that one of the scientists involved, Jeff Clune, uses these same algorithmic processes to generate believable imagery of terrestrial landscape features, such as volcanoes. These could then be used to model the topography of other planets, producing informed visual guesstimates of mountain ranges, ancient ocean basins, vast plains, valleys, even landscape features we might not yet have words to describe.

The notion that we would thus be seeing what AI thinks other worlds should look like—that, to view this in terms of art history, we are looking at the projective landscape paintings of machine intelligence—is a haunting one, as if discovering images of alien worlds in the daydreams of desktop computers.

(Spotted via Sean Lally; vaguely related, “We don’t have an algorithm for this”).

An Abundance of Glass

Going through some old notes, I found this great line from architect Kengo Kuma’s 2008 book Anti-Object, describing the conceptual ambition—and ultimate anticlimax—of modernist architecture. “Modernism set out to connect time and space,” he wrote, “but ultimately managed only to create objects that used an abundance of glass.”

Space Grain

[Image: A micrometeorite, photographed by Donald Brownlee, University of Washington].

A paper published last month in Geology reported “the discovery of significant numbers (500) of large micrometeorites (>100 μm) from rooftops in urban areas”—or “cosmic dust grains,” in the words of New Scientist, that have been “found on city rooftops for the first time.”

Although the samples were “collected primarily from roof gutters in Norway,” according to the original paper, their presence there “demonstrates that, contrary to current belief, micrometeorites can be collected from urban environments.” That is, the dust of ruined cosmic objects can be found intermixed with autumn leaves, cigarette butts, and brake pad dust, perhaps even accumulating on your bedroom window sill.

[Image: Gorgeous photograph of a micrometeorite by Matej Pašák].

Of course, it has long been possible to sample urban areas for micrometeorites, so this is not entirely new.

What’s fascinating, nonetheless, is that these micrometeorites are most likely to have arrived on Earth within the past six years, the study points out, but their size is notably larger than the average sample of micrometeorites from the recent geological record, indicating “variations in the extraterrestrial dust flux” on the scale of 800,000 years.

As New Scientist points out, this means that larger cosmic shifts can be deduced from the size and shape of these grains:

The differences [in size] may be linked to changes in the orbits of planets such as the Earth and Mars over millions of years, [researcher Matthew Genge] says. Resulting gravitational disturbances may have influenced the trajectory of the particles as they hurtled through space. This in turn would have an effect on the speed at which they slam into the Earth’s atmosphere and heat up.

“This find is important because if we are to look at fossil cosmic dust collected from ancient rocks to reconstruct a geological history of our solar system, then we need to understand how this dust is changed by the continuous pull of the planets,” Genge says.

Something’s changing in our local cosmic-dust environment, in other words, and evidence of this shift is slowly collecting on our roofs and sidewalks, accumulating in our gutters and sills.

(Conceptually related: War Sand).

The World as a Hieroglyph of Spatial Relationships Yet to be Interpreted

[Image: Courtesy Iris Automation].

In an interview published on the blog here a few years ago, novelist Zachary Mason, author of The Lost Books Of The Odyssey, pointed out something very interesting about the nearly limitless, three-dimensional space of the Earth’s atmosphere and how it relates to artificial intelligence.

“One of the problems with A.I.,” Mason explained back in 2010, “is that interacting with the world is really tough. Both sensing the world and manipulating it via robotics are very hard problems, and [these are] solved only for highly stripped-down special cases. Unmanned aerial vehicles, for instance, work well because maneuvering in a big, empty, three-dimensional void is easy—your GPS tells you exactly where you are, and there’s nothing to bump into except the odd migratory bird. Walking across a desert, though—or, heaven help us, negotiating one’s way through a room full of furniture in changing lighting conditions—is vastly more difficult.”

Another way of thinking about Mason’s comment—although Mason himself might disagree with the following statement—is that it is precisely the sky’s ease of navigation that makes it ideal for the emergence and testing of artificial intelligence. The Earth’s atmosphere, in other words—specifically because it is an unchallenging three-dimensional environment—is the perfect space for machine-vision algorithms and other forms of computational proto-intelligence to work out their most basic bugs.

Once they master the sky, then, autonomous machines can move on to more complicated environments, such as roads, mountains, forests. Cities.

In any case, I was thinking about Mason’s interview again earlier today when I read that drones are close to achieving “situational awareness”—albeit through visual, not artificially intelligent, means. In other words, it’s not AI—at least not yet—that will give unmanned aerial vehicles their much-needed ability to avoid colliding with other flying objects. Rather, it is a sufficiently advanced visual processing system that can identify and, more importantly, avoid potential obstacles.

Exactly such a system, TechCrunch claims, has been built by a Canadian firm called Iris Automation. Their system is able “to process visual data in real time, so it can see structures that suddenly appear, like a plane, flock of birds or another drone—not just static objects and waypoints that might be mapped using older technologies like GPS.” The company refers to this as “industrial drone collision avoidance,” which suggests a kind of on-board traffic management system for the sky. Air traffic control will be internal.

Now connect a drone’s “situational awareness” to sufficient processing power, and you could help steward into existence a computationally interesting form of autonomous intelligence.

To return to Zachary Mason’s computationally-inflected rewriting of The Odyssey, it would be AI as Athena, springing fully formed into the world from an empty sky.

A Window “Radically Different From All Previous Windows”

LIGO[Image: The corridors of LIGO, Louisiana, shaped like a “carpenter’s square”; via Google Earth].

It’s been really interesting for the last few weeks to watch as rumors and speculations about the first confirmed detection of gravitational waves have washed over the internet—primarily, at least from my perspective, because my wife, Nicola Twilley, who writes for The New Yorker, has been the only journalist given early access not just to the results but, more importantly, to the scientists behind the experiment, while writing an article that just went live over at The New Yorker.

It has been incredibly exciting to listen-in on partial conversations and snippets of overheard interviews in our home office here, as people like Kip Thorne, Rainer Weiss, and David Reitze, among a dozen others, all explained to her exactly how the gravitational waves were first detected and what it means for our future ability to study and understand the cosmos.

All this gloating as a proud husband aside, however, it’s a truly fascinating story and well worth mentioning here.

LIGO—the Laser Interferometer Gravitational-Wave Observatory—is a virtuoso act of precision construction: a pair of instruments, separated by thousands of miles, used to detect gravitational waves. They are shaped like “carpenter’s squares,” we read, and they stand in surreal, liminal landscapes: surrounded by water-logged swampland in Louisiana and “amid desert sagebrush, tumbleweed, and decommissioned reactors” in Hanford, Washington.

Ligo-Hanford [Image: LIGO, Hanford; via Google Earth].

Each consists of vast, seismically isolated corridors and finely calibrated super-mirrors between which lasers reflect in precise synchrony. These hallways are actually “so long—nearly two and a half miles—that they had to be raised a yard off the ground at each end, to keep them lying flat as Earth curved beneath them.”

To achieve the necessary precision of measurement, [Rainer Weiss, who first proposed the instrument’s construction] suggested using light as a ruler. He imagined putting a laser in the crook of the “L.” It would send a beam down the length of each tube, which a mirror at the other end would reflect back. The speed of light in a vacuum is constant, so as long as the tubes were cleared of air and other particles, the beams would recombine at the crook in synchrony—unless a gravitational wave happened to pass through. In that case, the distance between the mirrors and the laser would change slightly. Since one beam was now covering a shorter distance than its twin, they would no longer be in lockstep by the time they got back. The greater the mismatch, the stronger the wave. Such an instrument would need to be thousands of times more sensitive than any before it, and it would require delicate tuning, in order to extract a signal of vanishing weakness from the planet’s omnipresent din.

LIGO is the most sensitive instrument ever created by human beings, and its near-magical ability to pick up the tiniest tremor in the fabric of spacetime lends it a fantastical air that began to invade the team’s sleep. As Frederick Raab, director of the Hanford instrument, told Nicola, “When these people wake up in the middle of the night dreaming, they’re dreaming about the detector.”

Because of this hyper-sensitivity, its results need to be corrected against everything from minor earthquakes, windstorms, and passing truck traffic to “fluctuations in the power grid,” “distant lightning storms,” and even the howls of prowling wolves.

When the first positive signal came through, the team was actually worried it might not be a gravitational wave at all but “a very large lightning strike in Africa at about the same time.” (They checked; it wasn’t.)

Newton[Image: “Newton” (1795-c.1805) by William Blake, courtesy of the Tate].

The big deal amidst all this is that being able to study gravitational waves is very roughly analogous to the discovery of radio astronomy—where gravitational wave astronomy has the added benefit of opening up an entirely new spectrum of observation. Gravitational waves will let us “see” the fabric of spacetime in a way broadly similar to how we can “see” otherwise invisible radio emissions in deep space.

From The New Yorker:

Virtually all that is known about the universe has come to scientists by way of the electromagnetic spectrum. Four hundred years ago, Galileo began exploring the realm of visible light with his telescope. Since then, astronomers have pushed their instruments further. They have learned to see in radio waves and microwaves, in infrared and ultraviolet, in X-rays and gamma rays, revealing the birth of stars in the Carina Nebula and the eruption of geysers on Saturn’s eighth moon, pinpointing the center of the Milky Way and the locations of Earth-like planets around us. But more than ninety-five per cent of the universe remains imperceptible to traditional astronomy… “This is a completely new kind of telescope,” [David] Reitze said. “And that means we have an entirely new kind of astronomy to explore.”

Interestingly, in fact, my “seeing” metaphor, above, is misguided. As it happens, the gravitational waves studied by LIGO in its current state—ever-larger and more powerful new versions of the instrument are already being planned—“fall within the range of human hearing.”

If you want to hear spacetime, there is an embedded media player over at The New Yorker with a processed snippet of the “chirp” made by the incoming gravitational wave.

In any case, I’ve already gone on at great length, but the article ends with a truly fantastic quote from Kip Thorne. Thorne, of course, achieved minor celebrity last year when he consulted on the physics for Christopher Nolan’s relativistic time-travel film Interstellar, and he is not lacking for imagination.

Thorne compares LIGO to a window (and my inner H.P. Lovecraft reader shuddered at the ensuing metaphor):

“We are opening up a window on the universe so radically different from all previous windows that we are pretty ignorant about what’s going to come through,” Thorne said. “There are just bound to be big surprises.”

Go read the article in full!

“Building with metals not from Earth”

I missed the story last month that a company called Planetary Resources had successfully 3D-printed a small model using “metals not from Earth”—that is, metal harvested from a meteorite. “Transforming a chunk of space rock into something you can feed into a 3D printer is a pretty odd process. Planetary Resources uses a plasma that essentially turns the meteorite into a cloud that then ‘precipitates’ metallic powder that can be extracted via a vacuum system. ‘It condenses like rain out of a cloud,’ said [a company spokesperson], ‘but instead of raining water, you’re raining titanium pellets out of an iron nickel cloud.’ (…) ‘Everyone has probably seen an iron meteorite in a museum, now we have the tech to take that material and print it in a metal printer using high energy laser. Imagine if we could do that in space.’”

“A City on Mars is Possible. That’s What All This is About.”

Last week’s successful demonstration of a reusable rocket, launched by Elon Musk’s firm SpaceX, “was a critical step along the way towards being able to establish a city on Mars,” Musk later remarked. The proof-of-concept flight “dramatically improves my confidence that a city on Mars is possible,” he added. “That’s what all this is about.”

Previously, of course, Musk had urged the Royal Aeronautical Society to view Mars as a place where “you can start a self-sustaining civilization and grow it into something really big.” He later elaborated on these ideas in an interview with Aeon’s Ross Anderson, discussing optimistic but still purely speculative plans for “a citylike colony that he expects to be up and running by 2040.” In Musk’s own words, “If we have linear improvement in technology, as opposed to logarithmic, then we should have a significant base on Mars, perhaps with thousands or tens of thousands of people,” within this century.

(Image courtesy of SpaceX. Elsewhere: Off-world colonies of the Canadian Arctic and BLDGBLOG’s earlier interview with novelist Kim Stanley Robinson).

Dead Ringer

[Image: Mars’s moon, Phobos; courtesy NASA /JPL/University of Arizona].

Oh, to live another 40 million years… “One day,” Nature reports, “Mars may have rings like Saturn does”:

The martian moon Phobos, which is spiralling inexorably closer towards the red planet, will disintegrate to form a ring system some 20 million to 40 million years from now, according to calculations published on 23 November. Other research suggests that long grooves on Phobos’s surface may represent the first stages of that inevitable crack-up.

After that point, a red mineral ring will gradually coalesce from the dust storm, circling the planet in a desert halo.

In terms of human experience, 20-40 million years obviously dwarfs our anatomical and genetic history as modern Homo sapiens, and I am excessively confident that no humans will be around to witness this event. Nonetheless, it’s not actually that far off. The Earth itself is 4.5 billion years old; 20-40 million years is the geological blink of an eye. In a sense, we will just miss it.

For what it’s worth, Neal Stephenson’s most recent novel, Seveneves, is about a similar event—but set on Earth, not Mars.

“What if Earth’s moon suddenly and spontaneously broke apart into seven large pieces?” a review in the New York Times asked. “What would happen to life on Earth? It’s an intriguing premise, one that could conceivably go in any number of interesting directions. What would be the ramifications for every aspect of society, including economics, governance, the rule of law, privacy and security, not to mention even more fundamental matters like reproductive rights, religion and belief?”

In any case, read more over at Nature.