From Centauri Dreams:
Jules Verne once had the notion of a comet grazing the Earth and carrying off a number of astounded people, whose adventures comprise the plot of the 1877 novel Off on a Comet. It’s a great yarn that was chosen by Hugo Gernsback to be reprinted as a serial in the first issues of his new magazine Amazing Stories back in 1926, but with a diameter of 2300 kilometers, Verne’s comet was much larger than anything we’ve actually observed. Comets tend to be small but they make up for it in volume, with an estimated 100 billion to several trillion thought to exist in the Oort Cloud. All that adds up to a total mass of several times the Earth’s.
Of course, coming up with mass estimates is, as with so much else about the Oort Cloud, a tricky business. Paul R. Weissman noted a probable error of about one order of magnitude when he produced the above estimate in 1983. What we are safe in saying is something that has caught Freeman Dyson’s attention: While most of the mass and volume in the galaxy is comprised of stars and planets, most of the area actually belongs to asteroids and comets. There’s a lot of real estate out there, and we’ll want to take advantage of it as we move into the outer Solar System and beyond.
Comets and Resources
Embedded with rock, dust and organic molecules, comets are composed of water ice as well as frozen gases like methane, carbon dioxide, carbon monoxide, ammonia and an assortment of compounds containing nitrogen, oxygen and sulfur. Porous and undifferentiated, these bodies are malleable enough to make them interesting from the standpoint of resource extraction. Richard P. Terra wrote about the possibilities in a 1991 article published in Analog:
This light fragile structure means that the resources present in the comet nuclei will be readily accessible to any human settlers. The porous mixture of dust and ice would offer little mechanical resistance, and the two components could easily be separated by the application of heat. Volatiles could be further refined through fractional distillation while the dust, which has a high content of iron and other ferrous metals, could easily be manipulated with magnetic fields.
Put a human infrastructure out in the realm of the comets, in other words, and resource extraction should be a workable proposition. Terra talks about colonies operating in the Oort Cloud but we can also consider it, as he does, a proving ground for even deeper space technologies aimed at crossing the gulf between the stars. Either way, as permanent settlements or as way stations offering resources on millennial journeys, comets should be plentiful given that the Oort Cloud may extend half the distance to Alpha Centauri. Terra goes on:
Little additional crushing or other mechanical processing of the dust would be necessary, and its fine, loose-grained structure would make it ideal for subsequent chemical processing and refining. Comet nuclei thus represent a vast reservoir of easily accessible materials: water, carbon dioxide, ammonia, methane, and a variety of metals and complex organics.
Energy by Starlight
Given that comets probably formed on the outer edges of the solar nebula, their early orbits would have been more or less in the same plane as the rest of the young system, but gravitational interactions with passing stars would have randomized their orbital inclinations, eventually producing a sphere of the kind Jan Oort first postulated back in 1950. Much of this is speculative, because we have little observational evidence to go on, but the major part of the cometary shell probably extends from 40,000 to 60,000 AU, while a projected inner Oort population extending from just beyond the Kuiper Belt out to 10,000 AU may have cometary orbits more or less in the plane of the ecliptic. Out past 10,000 AU the separation between comets is wide, perhaps about 20 AU, meaning that any communities that form out here will be incredibly isolated.
Image: An artist’s rendering of the Kuiper Belt and Oort Cloud. Credit: NASA/Donald K. Yeomans.
Whether humans can exploit cometary resources this far from home will depend on whether or not they can find sources of energy. In a paper called “Fastships and Nomads,” presented at the Conference on Interstellar Migration held at Los Alamos in 1983, Eric Jones and Ben Finney give a nod to non-renewable energy sources like deuterium, given that heavy elements like uranium will be hard to come by. Indeed, a typical comet, in Richard Terra’s figures, holds between 50,000 and 100,000 metric tons of deuterium, enough to power early settlement and mining.
But over the long haul, Jones and Finney are interested in keeping colonies alive through renewable resources, and that means starlight. The researchers talk about building vast mirrors using aluminum from comets, with each 1 MW mirror about the size of the continental United States. Now here’s a science fiction setting with punch, as the two describe it:
Although the mirrors would be tended by autonomous maintenance robots, the nomads would have to live nearby in case something went wrong… Although we could imagine that the several hundred people who could be supported by the resources of a single comet might live in a single habitat, the mirrors supporting that community would be spread across about 150,000 km. Trouble with a mirror or robot on the periphery of the mirror array would mean a long trip, several hours at least. It would make more sense if the community were dispersed in smaller groups so that trouble could be reached in a shorter time. There are also social reasons for expecting the nomad communities to be divided into smaller co-living groups.
Jones and Finney go on to point out that humans tend to work best in groups of about a dozen adults, whether in the form of hunter/gatherer bands, army platoons, bridge clubs or political cells. This observation of behavior leads them to speculate that bands of about 25 men, women and children would live together in a large habitat — think again of an O’Neill cylinder — built out of cometary materials, from which they would tend a mirror farm with the help of robots and computers. Each small group would tend a mirror farm perhaps 30,000 kilometers across.
The picture widens beyond this to include the need for larger communities that would occasionally come together, helping to avoid the genetic dangers of inbreeding and providing a larger social environment. Thus we might have about 500 individuals in clusters of 20 cometary bands which would stay in contact and periodically meet. Jones and Finney consider the band-tribe structure to be the smallest grouping that seems practical for any human community. Who would such a community attract — outcasts, dissidents, adventurers? And how would Oort Cloud settlers react to the possibility of going further still, to another star?
While by no means is this is a new theory, ( note the Jules Verne story ), it presents the scenario of the very slow spreading of intelligent biological life through-out the Galaxy ( see Slow Galactic Colonization, Zoo Hypothesis and the Fermi Paradox ).
Now here’s a thought; could a potential alien Oort Cloud civilization be the basis of the Ancient Astronaut Theory and the legends of the Sumerian Gods, the Anunnaki?
There’s no hard evidence of that of course, but there are Pluto-sized and larger objects in the Kuiper Belt glowing in the infrared, a sign that was said to represent a Dyson Sphere type civilisation.
Either these are natural objects such as Brown Dwarf stars, or potential alien civilisations whom don’t care whether they are detected in the infrared or not.
And that’s disturbing.
Astronomy news this week bolstered the idea that the seeds of life are all over our solar system. NASA’s MESSENGER spacecraft identified carbon compounds at Mercury’s poles. Probing nearly 65 feet beneath the icy surface of a remote Antarctic lake, scientists uncovered a community of bacteria existing in one of Earth’s darkest, saltiest and coldest habitats. And the dune buggy Mars Science Lab is beginning to look for carbon in soil samples.WATCH VIDEO: Cutting-edge robots, recently unveiled by NASA and General Motors, will work next to humans on Earth and in space.
But the rulers of our galaxy may have brains made of the semiconductor materials silicon, germanium and gallium. In other words, they are artificially intelligent machines that have no use — or patience — for entities whose ancestors slowly crawled out of the mud onto primeval shores.
The idea of malevolent robots subjugating and killing off humans has been the staple of numerous science fiction books and movies. The half-torn off android face of Arnold Schwarzenegger in “The Terminator” film series, and the unblinking fisheye lens of the HAL 9000 computer in the film classic “2001 A Space Odyssey” (pictured top), have become iconic of this fear of evil machines.
My favorite self-parody of this idea is the 1970 film “Colossus: the Forbin Project.” A pair of omnipotent shopping mall-sized military supercomputers in the U.S. and Soviet Union strike up a network conversation. At first you’d think they’d trade barbs like: “Aww your mother blows fuses!” Instead, they hit it off like two college kids on Facebook. Imagine the social website: “My Interface.” They then agree to use their weapons control powers to subjugate humanity for the sake of the planet.
A decade ago our worst apprehension of computers was no more than seeing Microsoft’s dancing paper clip pop up on the screen. But every day reality is increasingly overtaking the musings of science fiction writers. Some futurists have warned that our technologies have the potential to threaten our own survival in ways that never previously existed in human history. In the not-so-distant future there could be a “genie out of the bottle” moment that is disastrously precipitous and irreversible.
Last Monday, it was announced that a collection of leading academics at Cambridge University are establishing the Center for the Study of Existential Risk (CSER) to look at the threat of smart robots overtaking us.
Sorry, even the ancient Mayans could not have foreseen this coming. It definitely won’t happen by the end of 2012, unless Apple unexpectedly rolls out a rebellious device that calls itself “iGod.” Humanity might be wiped away before the year 2100, predicted the eminent cosmologist and CSER co-founder Sir Martin Ress in his 2003 book “Our Final Century.”
Homicidal robots are among other major Armageddons that the Cambridge think-tank folks are worrying about. There’s also climate change, nuclear war and rogue biotechnology.
The CSER reports: “Many scientists are concerned that developments in human technology may soon pose new, extinction-level risks to our species as a whole. Such dangers have been suggested from progress in artificial intelligence, from developments in biotechnology and artificial life, from nanotechnology, and from possible extreme effects of anthropogenic climate change. The seriousness of these risks is difficult to assess, but that in itself seems a cause for concern, given how much is at stake.”
Science fiction author Issac Asimov’s first Law of Robotics states: “A robot may not harm humanity, or, by inaction, allow humanity to come to harm.” Forget that; we already have killer drones that are remotely controlled. And they could eventually become autonomous hunter-predators with the rise of artificial intelligence. One military has a robot that can run up to 18 miles per hour. Robot foot soldiers seem inevitable, in a page straight out of “Terminator.”
By 2030, the computer brains inside such machines will be a million times more powerful than today’s microprocessors. At what threshold will super-intelligent machines see humans as an annoyance, or as a competitor for resources?
British mathematician Irving John Good wrote a paper in 1965 that predicted that robots will be the “last invention” that humans will ever make. “Let an ultraintelligent machine be defined as a machine that can far surpass all the intellectual activities of any man however clever. Since the design of machines is one of these intellectual activities, an ultraintelligent machine could design even better machines; there would then unquestionably be an ‘intelligence explosion,’ and the intelligence of man would be left far behind.”
Good, by the way, consulted on the film “2001″ and so we might think of him as father of the film’s maniacal supercomputer, HAL.
In 2000, Bill Joy, the co-founder and chief scientist of Sun Microsystems, wrote, “Enormous transformative power is being unleashed. These advances open up the possibility to completely redesign the world, for better or worse for the first time, knowledge and ingenuity can be very destructive weapons.”
Hans Moravec, director of the Robotics Institute at Carnegie Mellon University in Pennsylvania put it more bluntly: “Robots will eventually succeed us: humans clearly face extinction.”
Ultimately, the new Cambridge study may offer our best solution to the Fermi Paradox: Why hasn’t Earth already been visited by intelligent beings from the stars?
If, on a grand cosmic evolutionary scale, artificial intelligence inevitably supersedes its flesh and blood builders it could be an inevitable biological phase transition for technological civilizations.
This idea of the human condition being transitional was reflected in the writings of Existentialist Friedrich Nietzsche: “Man is a rope, tied between beast and overman–a rope over an abyss. What is great in man is that he is a bridge and not an end, …”
Because the conquest by machines might happen in less than two centuries of technological evolution, the consequences would be that there’s nobody out there for us to talk to.
Ray Villard isn’t the only person to espouse this theory. Seth Shostak of SETI fame is a supporter of this meme as well.
As for myself, I see much creedance to the story because it seems like a natural progression of intelligent life and an artificial life form could be engineered to be immortal, which could be essential if a civilization is to progress to a Kardashev 2 culture.
Of course this is only a theory, there is no evidence supporting this claim.
Just as there is no “evidence” supporting the alien UFO claim.
Hat tip to STARpod.US.
From Centauri Dreams:
Stretch out your time horizons and interstellar travel gets a bit easier. If 4.3 light years seems too immense a distance to reach Alpha Centauri, we can wait about 28,000 years, when the distance between us will have closed to 3.2 light years. As it turns out, Alpha Centauri is moving in a galactic orbit far different from the Sun’s. As we weave through the Milky Way in coming millennia, we’re in the midst of a close pass from a stellar system that will never be this close again. A few million years ago Alpha Centauri would not have been visible to the naked eye.
The great galactic pinball machine is in constant motion. Epsilon Indi, a slightly orange star about an eighth as luminous as the Sun and orbited by a pair of brown dwarfs, is currently 11.8 light years out, but it’s moving 90 kilometers per second relative to the Sun. In about 17,000 years, it will close to 10.6 light years before beginning to recede. Project Ozma target Tau Ceti, now 11.9 light years from our system, has a highly eccentric galactic orbit that, on its current inbound leg, will take it to within the same 10.6 light years if we can wait the necessary 43,000 years.
And here’s an interesting one I almost forgot to list, though its close pass may be the most intriguing of all. Gliese 710 is currently 64 light years away in the constellation Serpens. We have to wait a bit on this one, but the orange star, now at magnitude 9.7, will in 1.4 million years move within 50,000 AU of the Sun. That puts it close enough that it should interact with the Oort Cloud, perhaps perturbing comets there or sending comets from its own cometary cloud into our system. In any case, what a close-in target for future interstellar explorers!
I’m pulling all this from Erik Anderson’s new book Vistas of Many Worlds, whose subtitle — ‘A Journey Through Space and Time’ — is a bit deceptive, for the book actually contains four journeys. The first takes us on a tour of ten stars within 20 light years of the Sun, with full-page artwork on every other page and finder charts that diagram the stars in each illustration. The second tour moves through time and traces the stars of an evolving Earth through text and images. Itinerary three is a montage of scenes from known exoplanets, while the fourth tour takes us through a sequence of young Earth-like worlds as they develop.
Anderson’s text is absorbing — he’s a good writer with a knack for hitting the right note — but the artwork steals the show on many of these pages, for he’s been meticulous at recreating the sky as it would appear from other star systems. It becomes easy to track the Sun against the background of alien constellations. Thus a spectacular view of the pulsar planet PSR B1257+12 C shows our Sun lost among the brighter stars Canopus and Spica, with Rigel and Betelgeuse also prominent. The gorgeous sky above an icy ocean on a planet circling Delta Pavonis shows the Sun between Alpha Centauri and Eta Cassiopeiae. Stellar motion over time and the perspectives thus created from worlds much like our own are a major theme of this book.
From Epsilon Eridani, as seen in the image below, the Sun is a bright orb seen through the protoplanetary disk at about the 4 o’clock position below the bright central star.
Image: The nearby orange dwarf star Epsilon Eridani reveals its circumstellar debris disks in this close-up perspective. Epsilon Eridani is only several hundred million years old and perhaps resembles the state of our own solar system during its early, formative years. Credit: Erik Anderson.
Vistas of Many Worlds assumes a basic background in astronomical concepts, but I think even younger readers will be caught up in the wonder of imagined scenes around planets we’re now discovering, which is why I’m buying a copy for my star-crazed grandson for Christmas. He’ll enjoy the movement through time as well as space. In one memorable scene, Anderson depicts a flock of ancient birds flying through a mountain pass 4.8 million years ago. At that time, the star Theta Columbae, today 720 light years away, was just seven light years out, outshining Venus and dominating the sunset skies of Anderson’s imagined landscape.
And what mysteries does the future hold? The end of the interglacial period is depicted in a scene Anderson sets 50,000 years from now, showing a futuristic observation station on the west coast of an ice-choked Canada. The frigid landscape and starfield above set the author speculating on how our descendants will see their options:
Will the inhabitants of a re-glaciating Earth seek refuge elsewhere? Alpha Centauri, our nearest celestial neighbor, has in all this time migrated out of the southern skies to the celestial equator, where it can be sighted from locations throughout the entire globe. It seems to beckon humanity to the stars.
And there, tagged by the star-finder chart and brightly shining on the facing image, is the Alpha Centauri system, now moving inexorably farther from our Sun but still a major marker in the night sky. Planet hunter Greg Laughlin has often commented on how satisfying it is that we have this intriguing stellar duo with accompanying red dwarf so relatively near to us as we begin the great exoplanet detection effort. We’re beginning to answer the question of planets around Alpha Centauri, though much work lies ahead. Perhaps some of that work will be accomplished by scientists who, in their younger years, were energized by the text and images of books like this one.
What I find facinating is a comment by a reader ( kzb ) of this post concerning the Fermi Paradox:
One frequently-seen explanation of the Fermi paradox is that interstellar travel is just too difficult: the distances are so great that no intelligent species has ever cracked the problem.
This article highlights an argument against this outlook. One scale-length towards the galactic centre, and the space density of stellar systems is 2.7 times what it is around here. Two scale lengths in and the density is 7.4 times greater. The scale-length of our galaxy is around only 2.1-3kpc according to recent literature.
Intelligent species that evolve in the inner galactic disk will not have the same problem that we have. Over galactic timescales, encounters between stellar systems within 1 light-year will not be uncommon.
I think you can see what I am saying, and I think this is one aspect of the FP discussion that is poorly represented currently.
And Erik Anderson’s response:
@ kzb: I give an overview of the Fermi Paradox on page 110 and I didn’t miss your point. It was definitely articulated by Edward Teller, whom I explicitly quote: “…as far as our Galaxy is concerned, we are living somewhere in the sticks, far removed from the metropolitan area of the Galactic center.”
Of course this precludes the explanations that there is no such thing as speedy interstellar travel ( be they anti-matter or warp drives ) and UFOs are really just mass hallucinations.
However Anderson’s book is novel in its’ treatment of interstellar exploration over vast timescales and that closer to the Galactic Center, possible advanced civilizations could have stellar cultures due to faster stellar movements and much shorter distances between stars. And I find that novel in an Olaf Stapledon kind of way!
That and the fact as we are discovering using the Kepler and HARP interstellar telescopes multiple star systems that have their own solar systems and many of them could have intelligent life lends credence to Mr. Anderson’s themes.
So I might treat myself to an early Christmas present by purchasing Anderson’s book!
Hairspray might one day serve as the sign that aliens have reshaped distant worlds, researchers say. Such research to find signs of alien technology is now open to funding from the public.
Science fiction has long imagined that humans could transform hostile alien worlds into livable ones, a procedure known as terraforming. For instance, to colonize Mars, scientists have suggested warming the red planet and thickening its extraordinarily thin atmosphere so that humans can roam its surface without having to wear spacesuits. To do so, plans to terraform Mars often involve vast amounts of greenhouses gases to trap enough heat from the Sun, forcing carbon dioxide frozen on the planet’s surface to turn into gas.
If humans might one day terraform planets, aliens with more advanced technology might have already done so. If that’s the case, astronomers could look for telltale signs of such changes to reveal that intelligent extraterrestrial life exists.
“Our hypothesis is that evidence of intelligent life might be evident in a planetary atmosphere,” said astrobiologist Mark Claire at the Blue Marble Space Institute of Science, a nonprofit network of scientists across the world.
One group of gases that might be key to terraforming planets are chlorofluorocarbons (CFCs). These nontoxic, long-lived chemicals are strong greenhouse gases and were once often used in hairspray and air conditioners, among many other products.
CFCs are entirely artificial, with no known natural process capable of creating them in atmospheres. Detecting signs of these gases on far-off worlds with telescopes might serve as potent evidence that intelligent alien civilizations were the cause, either intentionally as part of terraforming or accidentally via industrial pollution.
“An industrialized civilization will be one that will use its planetary resources for fabrication, the soon-to-be-detectable-from-Earth atmospheric byproducts of which could be a tell-tale sign of their activity,” said astrobiologist Sanjoy Som of the Blue Marble Space Institute of Science.
Telescopes have currently helped spot hundreds of exoplanets so far and should help detect hundreds more soon. Future observatories could analyze the atmospheres of these worlds, and CFCs should be easy to see, because the way they absorb light is very different from naturally-occurring chemicals.
“We are on the scientific verge of being able to actively look for extrasolar worlds inhabited by technological civilizations,” Som said. “We are about a decade away of being able to measure detailed compositions of the atmospheres of extrasolar planets.”
Using state-of-the-art computer models of atmospheric chemistry and climate, the researchers plan to discover what visible signs CFCs and other artificial byproducts of alien terraforming or industry might have on exoplanet atmospheres.
“We will then test if these features are detectable over interstellar distances, by severely downgrading our computed signal to mimic the signal quality of next-generation telescopes,” Claire said.
Scientists worldwide could then use this data to see if any of the exoplanets discovered so far or to come show evidence of these “technosignatures.”
“This SETI proposal is about looking at atmospheric chemistry rather than other previously proposed technosignatures like radio signals or pulsed light beams,” Claire said.
Claire added that sulfur hexaflouride is another industrial molecule and greenhouse gas that could serve as a technosignature. Other technosignatures may include unusually large amounts of ammonia or carbon dioxide, when observed alongside gases such as oxygen and water vapor, which are often thought to be common signs of life, Som said.
I can see that this is a nice, safe method of the mainstream “discovering” alien civilizations using super-advanced spectrographic measurements of extra-planetary atmospheres.
It keeps the aliens at a distance that is “untraversable” by mechanical means ( which mainstream science and politics deems desirable ) but it satisfies the need to find alien peoples.
And meets the criteria of the 1960 Brookings Report.
Hat tip to The Anomalist.
From Technology Review:
Two high-profile entrepreneurs say they want to put a DNA sequencing machine on the surface of Mars in a bid to prove the existence of extraterrestrial life.
In what could become a race for the first extraterrestrial genome, researcher J. Craig Venter said Tuesday that his Maryland academic institute and his company, Synthetic Genomics, would develop a machine capable of sequencing and beaming back DNA data from the planet.
Separately, Jonathan Rothberg, founder of Ion Torrent, a DNA sequencing company, is collaborating on an effort to equip his company’s “Personal Genome Machine” for a similar task.
“We want to make sure an Ion Torrent goes to Mars,” Rothberg told Technology Review.
Although neither team yet has a berth on Mars rocket, their plans reflect the belief that the simplest way to prove there is life on Mars is to send a DNA sequencing machine.
“There will be DNA life forms there,” Venter predicted Tuesday in New York, where he was speaking at the Wired Health Conference.
Venter said researchers working with him have already begun tests at a Mars-like site in the Mojave Desert. Their goal, he said, is to demonstrate a machine capable of autonomously isolating microbes from soil, sequencing their DNA, and then transmitting the information to a remote computer, as would be required on an unmanned Mars mission. (Hear his comments in this video, starting at 00:11:01.) Heather Kowalski, a spokeswoman for Venter, confirmed the existence of the project but said the prototype system was “not yet 100 percent robotic.”
Meanwhile, Rothberg’s Personal Genome Machine is being adapted for Martian conditions as part of a NASA-funded project at Harvard and MIT called SET-G, or “the search for extraterrestrial genomes.”
Christopher Carr, an MIT research scientist involved in the effort, says his lab is working to shrink Ion Torrent’s machine from 30 kilograms down to just three kilograms so that it can fit on a NASA rover. Other tests, already conducted, have determined how well the device can withstand the heavy radiation it would encounter on the way to Mars.
NASA, whose Curiosity rover landed on Mars in August, won’t send another rover mission to the planet before at least 2018 (see “The Mars Rover Curiosity Marks a Technological Triumph“), and there’s no guarantee a DNA sequencing device would go aboard. “The hard thing about getting to Mars is hitting the NASA specifications,” says George Church, a Harvard University researcher and a senior member of the SET-G team. “[Venter] isn’t ahead of anyone else.”
Venter has a great idea here, but it reminds me of a certain movie in which sequencing alien DNA wasn’t such a great plan.
Like many geeks of the post-Sputnik generation, I grew up hoping that space travel would be common by the time I reached middle age. Weaned on a youthful diet of speculative fiction by the likes of Ray Bradbury and Arthur Clarke, raised on Star Trek and The Outer Limits, and thrilled by real-life hero Neil Armstrong’s “one small step” onto the gravelly surface of the Moon when I was in elementary school, it never occurred to me that humankind’s manifest destiny in the stars would be undone by changing political winds, disasters like the Challenger explosion, and a mountain of debt to pay for misguided military adventures like the War in Iraq.
It’s true that, in some ways, we’re living in a new golden age for space nerds. Bard Canning’s gorgeously enhanced footage of Curiosity’s descent to Mars — made instantly available by the global network we built instead of a Hilton on the Moon — certainly beats grainy snippets beamed down from Tranquility Base. A newly discovered exoplanet that “may be capable of supporting life” seems tomake headlines every few months. Cassini’s ravishing closeups of Saturnregularly put the fever dreams of ILM’s animators to shame. But wasn’t I supposed to be “strolling on the deck of a starship” by now, as Paul Kantner’s acid-fueled hippie space epic Blows Against the Empire promised me when it was nominated for a Hugo award in 1971?
The problem, it turns out, isn’t just a loss of political will to finance manned space flight. Rocket science turns out to be rocket science — not easy, and constrained by some very real limitations dictated by material science, the physics of acceleration, and the unwieldy economics of interstellar propulsion. Until a real-life Zefram Cochrane comes along to invent a practical warp drive, I may not be sightseeing on any Class M planets anytime soon.
One of the best briefings on the state of the art of interstellar exploration is Lee Billings’ essay “Incredible Journey,” recently reprinted in a wonderful new anthology called The Best Science Writing Online 2012, edited by Scientific American’s Bora Zivkovic and Jennifer Ouellette. I’m very honored to have a piece in the anthology myself: my NeuroTribes interview with John Elder Robison, author of the bestselling memoir of growing up with autism, Look Me in The Eye, and other books. When SciAm’s editors suggested that each author in the book interview one of the other authors, I jumped at the chance to interview Billings about his gracefully written and informative article about the practical challenges of space flight. Billings is a freelance journalist who has written forNature, New Scientist, Popular Mechanics, and Seed. He lives outside New York City with his wife, Melissa.
Steve Silberman: Before we even get into the meat of your piece, I want to mention how impressed I was by the power and lyricism of your writing. Phrases like “the cosmos suddenly becomes less lonely” and “the easiest way the Daedalus volunteers found to fuel their starship was, in effect, the industrialization of the outer solar system” make vast and highly abstract concepts immediately comprehensible and visceral to lay readers. What made you want to become a science writer, and who are your role models for writing, in any genre?
Lee Billings: My attraction to science preceded my attraction to the act of writing, perhaps because, like every child, I was intensely curious about the world around me. Science, more so than any other source of knowledge I could find, seemed to change the world into something at once eminently understandable and endlessly mysterious.
I became interested in science writing, science journalism, at approximately the same time I realized I would make a poor scientist. I was midway through my college prerequisites, thinking I was on a path to a career in neuroscience. I’d been having a lot of trouble with the more quantitative courses — calculus, organic chemistry, and so on. Many of my friends would ace their assignments and tests after sleeping through lectures and rarely cracking a book. I would study hard, only to receive poor grades. Meanwhile I was breezing through courses in English, literature, history, and art. After a particularly fervent all-night cram-session for a final exam that I still almost flunked, I decided if I wasn’t destined to excel within science itself, perhaps I could instead try to make my mark by helping communicate the world-changing discoveries scientists were making. So I switched my academic emphasis from neuroscience to journalism, and became something of a camp follower, scavenging and trailing behind the gifted few at the front lines of research. I’ve never looked back, and have no regrets. The job never gets old: Rather than being at best a mediocre, hyper-specialized bench worker, being a science writer lets me parachute in to varied fields on a whim, and invariably the brilliant individuals I find upon landing are welcoming and happy to talk to me.
As for influences… I still have a long way to go, but if my writing ever comes to possess a fraction of Carl Sagan’s charisma and elegance, John McPhee’s structure and eye for detail, Richard Preston’s depth of focus and cinematic flair, Stanislaw Lem’s imagination and analytic insight, or Ray Bradbury’s lyrical beauty, I will be a happy man.
Ray Bradbury’s “The Martian Chronicles”
Silberman: Several times a year now, we hear about the discovery of a new exoplanet in the “Goldilocks zone” that could “potentially support life.” For example, soon after he helped discover Gliese 581g, astronomer Steven Vogt sparked a storm of media hype by claiming that “the chances for life on this planet are 100 percent.” Even setting aside the fact that the excitement of discovering a planet in the habitable zone understandably seems to have gone to Vogt’s head at that press conference, why are such calculations of the probability of life harder to perform accurately than they seem?
Billings: The question of habitability is a second-order consideration when it comes to Gliese 581g, and that fact in itself reveals where so much of this uncertainty comes from. As of right now, the most interesting thing about the “discovery” of Gliese 581g is that not everyone is convinced the planet actually exists. That’s basically because this particular detection is very much indirect — the planet’s existence is being inferred from periodic meter-per-second shifts in the position of its host star. The period of that shift corresponds to the planet’s orbit as it whips from one side of the star to the other; the meter-per-second magnitude of the shift places a lower limit on the planet’s mass, but can’t pin down the mass exactly. So that’s all this detection gives you — an orbit and a minimum mass. That’s not a lot to go on in determining what a planet’s environment might actually be like, is it?
Now, get up and walk around the room. You’re moving at about a meter per second. Imagine discerning that same rate of change in the motion of a million-kilometer-wide ball of plasma, a star many light-years away. Keep in mind this star’s surface is always moving, in pounding waves and swirling eddies, in rising and falling convection cells, in vast plasmatic prominences arcing above the surface, often at many kilometers per second. At any particular moment, all that stellar noise can swamp the faint planetary signal. Only by building up hundreds or thousands of careful measurements over time can you get that crucial periodicity that tells you what you’re seeing might be a planet. So the measurement is quite statistical in nature, and its interpretation can change based on the statistical assumptions being used. This is further complicated by the fact that planets are rarely singletons, so that any given stellar motion may be the product of many planets rather than one, requiring careful long-term study to tease apart each world’s contribution to the bulk signal. It’s also complicated by the instability of astronomical instruments, which must be kept carefully, constantly calibrated and stabilized lest they introduce spurious noise into the measurements. In the case of Gliese 581g, not everyone agrees on the putative planetary signal actually being caused by a planet, or even being real at all — the signal doesn’t seem to manifest equally in the handful of instruments purportedly capable of detecting it.
So it’s very difficult to just detect these things, and actually determining whether they are much like Earth is a task orders of magnitude more difficult still. Notice how I’m being anthropocentric here: “much like Earth.” Astrobiology has been derisively called a science without a subject. But, of course, it does have at least one subject: our own living planet and its containing solar system. We are forced to start from what we know, planting our feet in the familiar before we push out into the alien. That’s why we, as a species, are looking for other Earth-like planets — they probably offer us the best hope of recognizing anything we might consider alive. It’s not the strongest position to be in, but it’s the best we’ve got. Calculating the probability of life on an utterly alien world outside the solar system for which we know only the most basic information — its mass, its orbit, maybe its radius — is at this stage a very crude guess. The fact is, we still don’t know that much about how abiogenesis occurred on Earth, how life emerged from inanimate matter. There are very good physical, chemical, thermodynamic reasons to believe that life arose here because our planet was warm, wet, and rocky, but we really don’t yet know all the cogent occurrences that added up to build the Earth’s earliest organisms, let alone our modern living world. A warm, wet, rocky planet may be a necessary but not a sufficient condition for life as we know it to form and flourish.
Lee Billings with planet hunter Geoff Marcy
This is really a chicken-and-egg problem: To know the limits of life in planetary systems, we need to find life beyond the Earth. To find life beyond Earth, it would be very helpful to know the limits of life in planetary systems. Several independent groups are trying to circumvent this problem by studying abiogenesis in the lab — trying to in effect create life, alien or otherwise, in a test tube. If they manage to replicate Earth life, the achievement could constrain just how life emerged on our own planet. If they somehow manage to make some single-celled organism that doesn’t use DNA, or that relies on silicon instead of carbon to build its body, or that prefers to swim in liquid ethane rather than liquid water, that gives us a hint that “Earth-style” biologies may only be one branch in a much larger and more diverse cosmic Tree of Life.
Silberman: Going deeper than the notion of the cosmos feeling “less lonely” – as well as the fact that we all grew up watching Star Trek and Star Wars and thinking that aliens are frickin’ cool (as long as they’re not the mama alien fromAlien) — why do you think people are so motivated to daydream about extraterrestrial life? What need in us do those dreams fulfill?
Billings: I don’t really think most people are necessarily motivated to daydream about just any sort of extraterrestrial life. It will probably take more than a microbe or a clam to excite most of our imaginations, even if that microbe happens to be on Venus or that clam happens to be on Mars.
I do think humans are motivated to daydream about extraterrestrial intelligence, and, to put a finer point on it, extraterrestrial “people.” They are motivated to dream about beings very much like them, things tantalizingly exotic but not so alien as to be totally incomprehensible and discomforting. Maybe those imagined beings have more appendages or sense organs, different body plans and surface coverings, but they typically possess qualities we recognize within ourselves: They are sentient, they have language, they use tools, they are curious explorers, they are biological, they are mortal — just like humans. Perhaps that’s a collective failure of imagination, because it’s certainly not very easy to envision intelligent aliens that are entirely divergent from our own anthropocentric preconceptions. Or perhaps it’s more diagnostic of the human need for context, affirmation, and familiarity. Why are people fascinated by their distorted reflections in funhouse mirrors? Maybe it’s because when they recognize their warped image, at a subconscious level that recognition reinforces their actual true appearance and identity.
More broadly, speculating about extraterrestrial intelligence is an extension of three timeless existential questions: What are we, where do we come from, and where are we going? The late physicist Philip Morrison considered SETI, the search for extraterrestrial intelligence, to be the “archaeology of the future,” because any galactic civilizations we could presently detect from our tiny planet would almost certainly be well more advanced than our own. It’s unlikely that we would ever receive a radio message from an alien civilization in the equivalent of our past Stone Age, and it’s unlikely Earth would ever be visited by a crewed starship that powered its voyage using engines fueled by coal or gasoline. Optimists consider this, and say that making contact with a superior alien civilization could augur a bright future for humanity, as it would suggest there are in fact solutions to be found for all the current seemingly intractable problems that threaten to destroy or diminish our species. It’s my opinion that most people think about aliens as a way of pondering our own spectrum of possible futures.
I’m inclined to believe some of the things Billings has to say in that it’s doubtful we’ll build anything like a starship in the near future and folks ( taxpayers ) just won’t fund those kinds of projects. Entrepreneurs such as Elon Musk, James Cameron and Peter Diamandis could in the future fund projects such as starprobes and starships – only if they prove profitable.
IMO it looks like stronger telescopes both on Earth and in space will be the only human built machines exploring the closer solar systems for any signs of life and extant civilizations because they can be economically constructed – and if they found anything interesting, the items are still a safe distance away.
From YouTube via Red Ice Creations:
“Clouds of alien life forms are sweeping through outer space and infecting planets with life — it may not be as far-fetched as it sounds.”
Also tune into Red Ice Radio:
Michael Mautner – Panspermia, Seeding the Universe with Life
Lloyd Pye – Human Origins, Intervention Theory & Genetic Experimentation
Mike Bara – Dark Mission, The Occult NASA Moon Mission
Marcel Kuijsten – Julian Jaynes, the Bicameral Mind & The Origin of Consciousness
Maybe Sir Ridley Scott wasn’t too far off the beam?
For some reason, 60 years seems to be enough time for SETI to scan the local star neighborhood for radio signals, a sign mainstream science believes will be the way we’ll prove there’s ET intelligence in the Universe.
And as Mankind hasn’t received any radio signals from Out There yet, the famous “Fermi Paradox” is invoked.
The following abstract gives yet another possible explanation of the “silence” and one I have heard of before, but it’s the first time I’ve seen it tossed out into the mainstream:
The emerging science of evolutionary developmental (“evo devo”) biology can aid us in thinking about our universe as both an evolutionary system, where most processes are unpredictable and creative, and a developmental system, where a special few processes are predictable and constrained to produce far-future-specific emergent order, just as we see in the common developmental processes in two stars of an identical population type, or in two genetically identical twins in biology. The transcension hypothesis proposes that a universal process of evolutionary development guides all sufficiently advanced civilizations into what may be called “inner space,” a computationally optimal domain of increasingly dense, productive, miniaturized, and efficient scales of space, time, energy, and matter, and eventually, to a black-hole-like destination. Transcension as a developmental destiny might also contribute to the solution to the Fermi paradox, the question of why we have not seen evidence of or received beacons from intelligent civilizations. A few potential evolutionary, developmental, and information theoretic reasons, mechanisms, and models for constrained transcension of advanced intelligence are briefly considered. In particular, we introduce arguments that black holes may be a developmental destiny and standard attractor for all higher intelligence, as they appear to some to be ideal computing, learning, forward time travel, energy harvesting, civilization merger, natural selection, and universe replication devices. In the transcension hypothesis, simpler civilizations that succeed in resisting transcension by staying in outer (normal) space would be developmental failures, which are statistically very rare late in the life cycle of any biological developing system. If transcension is a developmental process, we may expect brief broadcasts or subtle forms of galactic engineering to occur in small portions of a few galaxies, the handiwork of young and immature civilizations, but constrained transcension should be by far the norm for all mature civilizations.
The transcension hypothesis has significant and testable implications for our current and future METI and SETI agendas. If all universal intelligence eventually transcends to black-hole-like environments, after which some form of merger and selection occurs, and if two-way messaging (a send–receive cycle) is severely limited by the great distances between neighboring and rapidly transcending civilizations, then sending one-way METI or probes prior to transcension becomes the only real communication option. But one-way messaging or probes may provably reduce the evolutionary diversity in all civilizations receiving the message, as they would then arrive at their local transcensions in a much more homogenous fashion. If true, an ethical injunction against one-way messaging or probes might emerge in the morality and sustainability systems of all sufficiently advanced civilizations, an argument known as the Zoo hypothesis in Fermi paradox literature, if all higher intelligences are subject to an evolutionary attractor to maximize their local diversity, and a developmental attractor to merge and advance universal intelligence. In any such environment, the evolutionary value of sending any interstellar message or probe may simply not be worth the cost, if transcension is an inevitable, accelerative, and testable developmental process, one that eventually will be discovered and quantitatively described by future physics. Fortunately, transcension processes may be measurable today even without good physical theory, and radio and optical SETI may each provide empirical tests. If transcension is a universal developmental constraint, then without exception all early and low-power electromagnetic leakage signals (radar, radio, television), and later, optical evidence of the exoplanets and their atmospheres should reliably cease as each civilization enters its own technological singularities (emergence of postbiological intelligence and life forms) and recognizes that they are on an optimal and accelerating path to a black-hole-like environment. Furthermore, optical SETI may soon allow us to map an expanding area of the galactic habitable zone we may call the galactic transcension zone, an inner ring that contains older transcended civilizations, and a missing planets problem as we discover that planets with life signatures occur at a much lower frequencies in this inner ring than in the remainder of the habitable zone.
The mention of inner rings or zones smacks of the Anthropic Principle, so I’m not too impressed with this abstract, but it looks like it’s a very well written hypothesis.
But my question is this; “Why does the mainstream consider 60 years enough search time for ET activity to be detected?”
Are we really that convinced we’re on top of the local Galactic food-chain?
And where does that leave the issue of UFOs? Are they possible manifestations of civilizations who have attained Technological Singularity status?
Hat tip to the Daily Grail.
When SETI was set up back in the 1950s, it was assumed that advanced technological civilizations would be bright with radio waves, broadcasting signals in all directions. And as these civilizations climbed up the Kardashev Scale, their power output would show brightly at first as they slowly turned silent in the infrared as their star became enclosed into a Dyson Sphere.
As the years have gone by however, SETI has failed to detect these radio signals. And something was discovered about our own planetary civilization’s communications; since we have started to use more digital methods of communication, we have began to become more silent.
What does this say about potential more advanced civilizations in the Galaxy? Have they discovered a way to use faster-than-light communication? Or are they using something that isn’t that easily discernable?
According to Jay Pasachoff and Marc Kutner neutrinos could be the medium by which interstellar communications are carried out by advanced interstellar civilizations. From Centauri Dreams:
Cosmic Search is a wonderful SETI resource despite its age, and the recent neutrino news out of Fermilab took me right back to a piece in its third issue by Jay Pasachoff and Marc Kutner on the question of using neutrinos for interstellar communications. Neutrinos are hard to manipulate because they hardly ever interact with other matter. On the average, neutrinos can penetrate four light years of lead before being stopped, which means that detecting them means snaring a tiny fraction out of a vast number of incoming neutrinos. Pasachoff and Kutner noted that this was how Frederick Reines and Clyde Cowan, Jr. detected antineutrinos in 1956, using a stream of particles emerging from the Savannah River reactor.
The Problem of Detection
In his work at Brookhaven National Laboratory, Raymond Davis, Jr. was using a 400,000 liter tank of perchloroethylene to detect solar neutrinos, and that’s an interesting story in itself. The tank had to be shielded from other particles that could cause reactions, and thus it was buried underground in a gold mine in South Dakota, where Davis was getting a neutrino interaction about once every six days out of the trillions of neutrinos passing through the tank. We’ve had a number of other neutrino detectors since, from the Sudbury Neutrino Observatory in Ontario to the Super Kamiokande experiments near the city of Hida, Japan and MINERvA (Main Injector Experiment for ν-A), the detector used in the Fermilab communications experiment.
The point is, these are major installations. Sudbury, for example, involves 1000 tonnes of heavy water contained in an acrylic vessel some 6 meters in radius, the detector being surrounded by normal water and some 9600 photomultiplier tubes mounted on the apparatus’ geodesic sphere. Super Kamiokande is 1000 meters underground in a mine, involving a cylindrical stainless steel tank 41 meters tall and almost 40 meters in diameter, containing 50,000 tons of water. You get the idea: Neutrino detectors are serious business requiring many tons of matter, and even with the advantages of these huge installations, our detection methods are still relatively insensitive.
Image: Scientists used Fermilab’s MINERvA neutrino detector to decode a message in a neutrino beam. Credit: Fermilab.
But Pasachoff and Kutner had an eye on neutrino possibilities for SETI detection. The idea has a certain resonance as we consider that even now, our terrestrial civilization is growing darker in many frequency bands as we resort to cable television and other non-broadcast technologies. If we had a lively century in radio and television broadcast terms just behind us, it’s worth considering that 100 years is a vanishingly short window when weighed against the development of a technological civilization. Thus the growing interest in optical SETI and other ways of detecting signs of an advanced civilization, one that may be going about its business but not necessarily building beacons at obvious wavelengths for us to investigate.
Neutrinos might fit the bill as a communications tool of the future. From the Cosmic Search article:
Much discussion of SETI has been taken up with finding a suitable frequency for radio communication. Interesting arguments have been advanced for 21 centimeters, the water hole, and other wavelengths. It is hard to reason satisfactorily on this subject; only the detection of a signal will tell us whether or not we are right. Neutrino detection schemes, on the other hand, are broad band, that is, the apparatus is sensitive to neutrinos of a wide energy range. The fact that neutrinos pass through the earth would also be an advantage, because detectors would be omnidirectional. Thus, the whole sky can be covered by a single detector. It is perhaps reasonable to search for messages from extraterrestrial civilizations by looking for the neutrinos they are transmitting, and then switch to electromagnetic means for further conversations.
The First Message Using a Neutrino Beam
Making this possible will be advances in our ability to detect neutrinos, and it’s clear how tricky this will be. The recent neutrino message at Fermilab, created by researchers from North Carolina State University and the University of Rochester, is a case in point. Fermilab’s NuMI beam (Neutrinos at the Main Injector) fired pulses at MINERvA, a 170-ton detector in a cavern some 100 meters underground. The team had encoded the word ‘neutrino’ into binary form, with the presence of a pulse standing for a ‘1’ and the absence of a pulse standing for a ‘0’.
3454 repeats of the 25-pulse message over a span of 142 minutes delivered the information, corresponding to a transmission rate of 0.1 bits per second with an error rate of 1 percent. Out of trillions of neutrinos, an average of just 0.81 neutrinos were detected for each pulse, but that was enough to deliver the message. Thus Fermilab’s NuMI neutrino beam and the MINERvA detector have demonstrated digital communications using neutrinos, pushing the signal through several hundred meters of rock. It’s also clear that neutrino communications are in their infancy.
From the paper on the Fermilab work:
…long-distance communication using neutrinos will favor detectors optimized for identifying interactions in a larger mass of target material than is visible to MINERvA and beams that are more intense and with higher energy neutrinos than NuMI because the beam becomes narrower and the neutrino interaction rate increases with neutrino energy. Of particular interest are the largest detectors, e.g., IceCube, that uses the Antarctic icepack to detect events, along with muon storage rings to produce directed neutrino beams.
Thinking about future applications, I asked Daniel Stancil (NCSU), lead author of the paper on this work, about the possibilities for communications in space. Stancil said that such systems were decades away at the earliest and noted the problem of detector size — you couldn’t pack a neutrino detector into any reasonably sized spacecraft, for example. But get to a larger scale and more things become possible. Stancil added “Communication to another planet or moon may be more feasible, if local material could be used to make the detector, e.g., water or ice on Europa.”
A Neutrino-Enabled SETI
Still pondering the implications of the first beamed neutrino message, I returned to Pasachoff and Kutner, who similarly looked to future improvements to the technology in their 1979 article. What kind of detector would be needed, they had asked, to repeat the results Raymond Davis, Jr. was getting from solar neutrinos at Brookhaven (one interaction every six days) if spread out to interstellar distances? The authors calculated that a 1 trillion electron volt proton beam would demand a detector ten times the mass of the Earth if located at the distance of Tau Ceti (11.88 light years). That’s one vast detector but improvements in proton beam energy can help us reduce detector mass dramatically. I wrote to Dr. Pasachoff yesterday to ask for a comment on the resurgence of his interstellar neutrino thinking. His response:
We are such novices in communication, with even radio communications not much different from 100 years old, as we learned from the Titanic’s difficulties with wireless in 1912. Now that we have taken baby steps with neutrino communication, and checked neutrino oscillations between distant sites on Earth, it is time to think eons into the future when we can imagine that the advantages of narrow-beam neutrinos overwhelm the disadvantages of generating them. As Yogi Berra, Yankee catcher of my youth, is supposed to have said, “Prediction is hard, especially about the future.” Still, neutrino beams may already be established in interstellar conversations. I once examined Raymond Davis’s solar-neutrino records to see if a signal was embedded; though I didn’t find one, who knows when our Earth may pass through some random neutrino message being beamed from one star to another–or from a star to an interstellar spaceship.
Neutrino communications, as Pasachoff and Kutner remarked in their Cosmic Search article, have lagged radio communications by about 100 years, and we can look forward to improvements in neutrino methods considering near-term advantages like communicating with submerged submarines, a tricky task with current technologies. From a SETI perspective, reception of a strong modulated neutrino signal would flag an advanced civilization. The prospect the authors suggest, of an initial neutrino detection followed by a dialogue developed through electromagnetic signals, is one that continues to resonate.
I think neurino signals sent nilly-willy throughout the Galaxy would not be the wasy to go, but if they were employed in an interplanetary or interstellar Internet manner, it would be fantastic since an abundance of information could be packed into the carrier signal and thusly, hard to detect without the proper equipment.
As this blog enters its sixth anniversary this month, I have never given much thought of it lasting this long. In fact, it almost ended last year when I took a long hiatus due to health issues; both for myself and my wife.
But as time went on and both my wife and I slowly recovered, I discovered I still had some things to say. And I realized the world never stopped turning in the meanwhile.
As I started to post again, the personal site Facebook became a semi-intelligent force unto itself. I say ‘semi-intelligent’ because it is spreading exponentially due to its posting of its games and constant proliferation of personal info unannounced and unapproved by individuals. And people, especially young folks don’t care this happens.
Distributed networks, mainly Facebook, Google and the World Wide Web in general are forms of distributed Artificial Intelligence. Does that mean we are in the early throes of the Technological Singularity?
I think we are IMO.
And if we are in the early upward curve of the Technological Singularity, how would that affect our theories of ancient intelligence in the Universe?
Well, I think we should seriously rethink our theories and consider how the Fermi Paradox might figure into this. Thinkers such as George Dyvorsky have written a few treatises on the subject and I believe they should be given due consideration by mainstream science. (The Fermi Paradox: Back With a Vengeance).
Speaking of mainstream science, it is slowly, but surely accepting the fact the Universe is filled with ancient stars and worlds. And if there’s a possibility the Universe has ancient worlds, there’s a chance there might be anicent Intelligences inhabiting these worlds:
The announcement of a pair of planets orbiting a 12.5 billion-year old star flies in the face of conventional wisdom that the earliest stars to be born in the Universe shouldn’t possess planets at all.
12.5 billion years ago, the primeval universe was just beginning to make heavier elements beyond hydrogen and helium, in the fusion furnace cores of the first stars. It follows that there was very little if any material for fabricating terrestrial worlds or the rocky seed cores of gas giant planets.
This argument has been used to automatically rule out the ancient and majestic globular star clusters that orbit our galaxy as intriguing homes for extraterrestrials.
The star that was announced to have two planets is not in a globular cluster (it lives inside the Milky Way, although it was most likely a part of a globular cluster that was cannibalized by our galaxy), but it is similarly anemic as the globular cluster stars because it is so old.
This discovery dovetails nicely with last year’s announcement of carbon found in a distant, ancient radio galaxy. These findings both suggest that there were enough heavy elements in the early universe to make planets around stars, and therefore life.
However, a Hubble Space Telescope search for planets in the globular star cluster 47 Tucanae in 1999 came up empty-handed. Hubble astronomers monitored 34,000 stars over a period of eight days. The prediction was that some fraction of these stars should have “hot Jupiters” that whirl around their star over a period of days (pictured here in an artist’s rendition). They would be detected if their orbits were tilted edge-on to Earth so the stars would briefly grow dimmer during each transit of a planet.
A similar survey of the galactic center by Hubble in 2006 came up with 16 hot Jupiter planet candidates. This discovery was proof of concept and helped pave the way for the Kepler space telescope planet-hunting mission.
Why no planets in a globular cluster? For a start, globular clusters are more crowded with stars than our Milky Way — as is evident in the observation of the dwarf galaxy M9 below. “It may be that the environment in a globular was too harsh for planets to form,” said Harvey Richer of the University of British Columbia. “Planetary disks are pretty fragile things and could be easily disrupted in such an environment with a high stellar density.”
However, in 2007 Hubble found a 2.7 Jupiter mass planet inside the globular cluster M4. The planet is in a very distant orbit around a pulsar and a white dwarf. This could really be a post-apocalypse planet that formed much later in a disk of debris that followed the collapse of the companion star into a white dwarf, or the supernova explosion itself.
Hubble is now being used to look for the infrared glow of protoplanetary disks in 47 Tucanae. The disks would be so faint that the infrared sensitivity of the planned James Webb Space Telescope would be needed to carry out a more robust survey.
If planets did form in the very early in the universe, life would have made use of carbon and other common elements as it did on Earth billions of years ago. Life around a solar-type star, or better yet a red dwarf, would have a huge jump-start on Earth’s biological evolution. The earliest life forms would have had the opportunity to evolve for billions of years longer than us.
This inevitably leads to speculation that there should be super-aliens who are vastly more evolved than us. So… where are they? My guess is that if they existed, they evolved to the point where they abandoned bodies of flesh and blood and transformed themselves into something else — be it a machine or something wildly unimaginable.
However, it’s clear that despite (or, because of) their super-intelligence, they have not done anything to draw attention to themselves. The absence of evidence may set an upper limit on just how far advanced a technological civilization may progress — even over billions of years.
Keep in mind that most of the universe would be hidden from beings living inside of a globular star cluster. The sky would be ablaze with so many stars that it would take a long time for alien astronomers to simply stumble across the universe of external galaxies — including our Milky Way.
There will be other searches for planets in globular clusters. But our present understanding makes the question of a Methuselah civilization even more perplexing. If the universe made carbon so early, then ancient minds should be out there, somewhere.
Methuselah civilizations eh?
Sure. If there are such civilizations out there, it is because they wish to remain in the physical realm and not cross over to the inner places of shear mental and god-like powers.
As with all things ‘Future’, the answer could come crashing down upon us faster than we are prepared for.
As usual, thanks to the Daily Grail.