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Gravitational Lensing, Interstellar Cinematography, and the Future of Magical Warfare in Space

[Image: An example of gravitational lens effects, via Wikipedia.]

Over at WIRED, Daniel Oberhaus, author of the recent book Extraterrestrial Languages, takes a look at some proposals from NASA’s Innovative Advanced Concept (NIAC) program. “Among this year’s NIAC grants,” Oberhaus writes, “are proposals to turn a lunar crater into a giant radio dish, to develop an antimatter deceleration system, and to map the inside of an asteroid. But the most eye-popping concept of the bunch was advanced by Slava Turyshev, a physicist at NASA’s Jet Propulsion Laboratory who wants to photograph an exoplanet by using the sun as a giant camera lens.”

There is much more specific information in Oberhaus’s piece—about gravitational lensing, etc. etc.—but the following detail is killer. “Unlike a camera lens,” we read, “the sun doesn’t have a single focal point, but a focal line that starts around 50 billion miles away and extends infinitely into space. The image of an exoplanet can be imagined as a tube less than a mile in diameter centered on this focal line and located 60 billion miles away in the vast emptiness of interstellar space. The telescope must align itself perfectly within this tube so that you could draw an imaginary line from the center of the telescope through the center of the sun to a region on the exoplanet.”

Cameras in space, waiting to be discovered—or where astronomy and cinematography become the same pursuit.

Seen this way, the solar system is more like a maze of optical effects, a topology of entangled image-tubes and horizon lines, of gravitational mirages streamed from one side of the galaxy to the next, torqued, lensed, and ribboned into geometric shapes we then struggle to unknot with the right billion-dollar instrumentation.

Along those lines, recall this excellent post on Xenogothic following last year’s unprecedented “photo” taken of a black hole. According to Xenogothic, this curious anti-photo depicting the absence of light reveals “the true, formless nature of photography and our photographies-to-come… The further out into the imperceptible universe we reach, the quicker we must get used to seeing images which are ostensibly not-for-us.” Imaging black holes is art history by other means.

[Image: Black hole, via Xenogothic.]

In fact, all of this reminds me of one of my favorite museums in the world, the National Museum of Cinema in Turin, Italy, which begins its history of cinema with a display of circular mirrors, anamorphic paintings, perspectival diagrams, and other optical tricks that, in the proper historical context, seem indistinguishable from magic. The birth of “cinema,” we might say, occurred when someone distorted light with mirrors; its origins are rooted in illusion and reflection, not projection and electricity.

In any case, imagine magicians of the near-future, performing for audiences aboard relativistic spacecraft, making stars disappear by manipulating image-tubes in the voids between planets. Gravitational lensing will pass from a niche science into popular spectacle.

And then, of course—the inevitable next step in a Christopher Priest novel—these magical effects of stellar camouflage, Xenogothic’s “photographies-to-come,” will become weaponized, militarized, transformed into tools for catastrophically redirecting light through space and extinguishing distant worlds.

From an optical effect in the prehistory of cinema to relativistic gravitational lensing in the abstracts of NASA to future galactic conquerors casually folding closed their image-tubes and making entire planets disappear.

Tone Fields Larger Than Stars

[Image: From “Probing Cosmic-Ray Transport with Radio Synchrotron Harps in the Galactic Center,” by Timon Thomas, Christoph Pfrommer, and Torsten Enßlin.]

The above image, as described by Susanna Kohler over at AAS Nova, depicts an ultra-large-scale magnetic “harp” near the center of our galaxy, emitting radio waves. The black lines apparently “span several light-years.”

As Kohler writes, where the parenthetical comments are her own, “a team of scientists argues that this cosmic music is caused by a massive star or a pulsar (a magnetized neutron star) plunging through an ordered magnetic field in the galactic center. As the star crosses (moving upward, in the image above) bundles of field lines, it discharges high-energy cosmic rays that travel in either direction along the bundles, emitting radio waves.”

It’s a kind of cosmic the re min—an instrument where the “musician controls volume and pitch using her hands to interfere with electromagnetic fields generated by the device”—a huge and ancient instrument playing itself in space.

Dimming to Explode

[Image: Betelgeuse, before dimming; photo by ESO, M. Montargès et al, via NASA.]

There are many interesting things about the dimming of Betelgeuse, a giant star in the constellation of Orion’s belt—perhaps a sign that the star is on the verge of exploding in a giant supernova—including the fact that I remember talking about this very scenario in a poetry workshop more than two decades ago. Here we are, still waiting for that light.

[Image: Betelgeuse, during dimming; photo by ESO, M. Montargès et al, via NASA.]

Betelgeuse, of course, is more than 700 lightyears from Earth, which means that it could very well have exploded centuries ago—it could, technically speaking, not even be there anymore, and wasn’t there for your parents or their parents—but the light from that catastrophe simply hasn’t reached Earth. We are always out of synch with the stars we think we’re seeing, unwitting recipients of dead news from above.

Delayed explosions, stars that are no longer there, constellations made of ghosts: the death–or not—of Betelgeuse is the metaphor that gives on giving, as evidenced by the fact that, even in my own lifetime, the topic has come up once again.

But what’s also so interesting about this sort of news is its juxtaposition between human timescales and astral ones, or human awareness colliding with cosmic time more generally: the implication that the universe is capable of extraordinary events that, in the long-term scheme of things, are actually extraordinarily common, but, from within the limits of a human lifetime, even the lifetime of an entire animal species, appear so rare as perhaps never to be encountered. To never be witnessed or even thought possible. There are things that happen only every 100 million years, every billion years, yet here we are right in the middle of it, unaware of strange gravitational inversions or churning, stroboscopic tides of light, of impossible stars and energy forms stranger than all mythology. Black chemistries in space, awaiting catalysis.

There could be physical processes as regular as clockwork pinging off like fireworks—constant, dead rhythms pulsing through the cosmos every two billion years—but our species will never see, hear, or know, because we simply never overlap.

We inhabit the same universe but not the same time.

International House of Wobbling

[Image: The Gaithersburg Latitude Observatory, via the U.S. Library of Congress].

The Gaithersburg Latitude Observatory was designed in 1899 as part of a ring of similar facilities around the world, all constructed at the same latitude.

[Images: The Gaithersburg Latitude Observatory, via the U.S. Library of Congress].

Each building was installed at its specific location in order to collaborate in watching a particular star, and—as revealed by any inconsistencies of measurement—to find evidence of the Earth’s “wobble.” This was part of the so-called “International Latitude Service.”

[Image: The Gaithersburg Latitude Observatory, via the U.S. Library of Congress].

The building seen here basically operated like a machine, with a sliding-panel roof controlled by a rope and pulley, and a solid concrete foundation, isolated from the building itself, on which stood a high-power telescope.

[Image: The Gaithersburg Latitude Observatory, via the U.S. Library of Congress].

This pillar gives the building a vaguely gyroscopic feel, or perhaps something more like the spindle of a hard drive: a central axis that grounds the building and allows it to perform its celestial mission.

[Image: The Gaithersburg Latitude Observatory, via the U.S. Library of Congress].

What’s interesting, however, is that this absolutely heroic building program—a structure for measuring heavenly discrepancies and, thus, the wobble of the Earth—is hidden inside such an unremarkable, everyday appearance.

[Image: A photo of the Gaithersburg Latitude Observatory, via NOAA].

It’s a kind of normcore beach hut that wouldn’t be out of place on Cape Cod, with one eye fixed on the stars, a geodetic device revealing our planet’s wobbly imperfections, masquerading as vernacular architecture.

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).

Skyfall

Although the Earth itself will be coming to its fiery and magmatic end in 7 billion years’ time, its nighttime skies will be undergoing an extraordinary slow-motion light-show: the merging of the Milky Way and Andromeda galaxies.

An animation released last summer by NASA, called “What the Night Sky Will Look Like Over the Next 7 Billion Years” and embedded above, depicts the glowing filaments of these two galaxies, like plate tectonics in space, crashing together, gravitationally distorting one another, and then merging in a featureless cloud of light.

[Image: Via HubbleSite].

In his weird, brilliant, and unimaginably dense book The Invention of the Zero poet Richard Kenney exclaims, “Imagine, all new constellations! …a seethe / and flume of unfamiliar skies.”

But such skies are not merely the domain of speculative poetry, as they are, in fact, on their way, roiling toward us in billion-year-long collisions that we, as a species, will never see the true light of.

[Image: Via HubbleSite].

I’m reminded of an essay by geologist Steven Dutch, at the University of Wisconsin, Green Bay, called “The Earth Has A Future,” originally published in the May 2006 issue of Geosphere.

Advocating what he calls a “futurist approach” to the planetary sciences, Dutch points out that “a million years is relatively short in geologic terms. For example, even the fastest plates, moving on the order of 15 cm/yr, will have moved only 150 km in a million years, enough to have very significant local geological effects but scarcely enough to be casually noticeable on a globe.”

However, Dutch’s “futurist approach” to landscape studies becomes particularly fascinating when he turns his attention upward, to the sky, looking out beyond the Earth to what stars and their constellations might look like in roughly one million years. Dutch predicts, for instance, that “distant star patterns like Orion should be recognizable” for several hundred thousand years, “but many constellations will have changed noticeably.”

In other words, the sky is always—even now—adrift, already fulfilling Kenney’s “seethe and flume of unfamiliar skies.”

[Image: Via HubbleSite].

But that’s just a million years. Multiply that by seven-and-a-half thousand, and the heavenly distortions torquing through the skies above us become magical even to contemplate.