Orphan stars

Here in the twenty-first century, it's easy to deride the ancients for their belief that the Earth was the center of the cosmos, and everything revolved around it.

After all, that's certainly what it looks like.  We still talk about the Sun "rising" and "setting" -- even though we know the Earth orbits the Sun, the terms are a convenient way to describe our experience.  (Well, to be absolutely accurate, the Earth and the Sun both orbit their common center of gravity, but the Sun is so much more massive that to say the Earth orbits the Sun is substantially accurate.)

Even after Copernicus showed that the heliocentric model is correct, it still left us to explain the apparent motion of the stars.  As we gradually learned more, we found that we are far from the center of the universe; we orbit a rather ordinary star in the outer reaches of a rather ordinary galaxy.  It still boggles my mind that they figured this last part out.  Not only are we at the periphery of the Milky Way, and therefore seeing it edge-on, a lot of the bright central bits are obscured by dust.  But even so, we've now amassed enough data to understand that the Milky Way is a barred spiral galaxy, and even to map out its main features.

If ever there was an image you need to study in detail, this is it.  Take a look at the original, close up.  The Solar System is in the Orion Arm, directly down from the center of the galaxy.  The thing that blew me away is the circle marked "Naked Eye Limit" -- literally every star you have ever seen without the use of a telescope is in that little circle.  [Image licensed under the Creative Commons Pablo Carlos Budassi, Milky way map, CC BY-SA 4.0]

And if you want to feel even smaller, the Milky Way is just one of a hundred thousand galaxies in the Laniakea Supercluster, which stretches over a distance of 520 million light years.  And weirdest of all, the entire supercluster's center of gravity is at a point called "the Great Attractor," but we can't see what's there because it's on the other side of the Milky Way's center.  If there's actually something there holding the entire Laniakea Supercluster together, it's currently hidden, and will be for another hundred million years -- at which point the Solar System will have made a half-revolution around the Milky Way and will be able to see what, if anything, is out there.

The reason this topic comes up is a recent survey by the Hubble Space Telescope that found good evidence that there are stars -- and therefore probably associated planetary systems -- out there in the space between the galaxies.  It picked up "intracluster light," a faint glow produced by these unaffiliated stars.  What was fascinating and unexpected is that when you look at progressively more distant regions of space -- and thus, back further in time -- the amount of that ghostly glow doesn't change, which implies that earlier models attributing these orphan stars to the chaos resulting from galactic mergers or close side-swipes can't be true.  It looks like there have always been stars floating out there between galaxies.

Think about what it'd be like to live on a planet around one of those.  Remember the circle on the map marked "naked eye limit?"  Within the naked eye limit of a planet around one of those orphans, there would be nothing.  The skies would be pitch black... until the telescope was invented.  And then, what a surprise they'd get!  (If they'd even think of inventing the telescope -- why would you, when it appears that there's nothing up there to see?)

"We don't exactly know what made [the orphan stars] homeless," said astrophysicist James Jee of Yonsei University, who co-authored the study.  "Current theories cannot explain our results, but somehow they were produced in large quantities in the early universe.  In their early formative years, galaxies might have been pretty small and they bled stars pretty easily because of a weaker gravitational grasp."

More data should come in from the newly-deployed James Webb Space Telescope, and that may clarify this fascinating conundrum.

The ancients found it unsettling that we might not be at the center of the universe, and later that the universe is astonishingly larger than they ever dreamed.  Me, I find it reassuring.  My own little petty day-to-day concerns and worries seem like nothing at all on the scale of the Laniakea Supercluster.  Looking up on the next clear night, remember that little circle marked "naked eye limit" -- and think about what there is up in the night sky that you're not seeing.

Including the ghostly light of millions of orphan stars, lost in the deeps of interstellar space.

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Pottery in motion

Making pottery is a complicated enterprise.

I say this from some degree of personal experience.  About ten years ago, on the urging of my artist wife, I took a class to learn how to throw pottery.  For those of you who have no experience with this particular avocation, I'm not talking about hurling plates against the wall, which, of course, you wouldn't need to take a class for.  "Throwing," in pottery parlance, is the process of using a spinning pottery wheel to shape symmetrical vessels out of clay.  Some people still use old-fashioned "kick wheels" -- where the axle of the wheelhead attaches to a heavy stone disk set in motion with the feet, and the momentum of the disk keeps the wheel spinning (for a while, at least).  Fortunately -- because learning to use a kick wheel takes a whole different level of coordination -- I learned to throw on an electric wheel, the speed of which is controlled by a foot pedal a little like the accelerator of a car.

Which is hard enough.  The first pieces I made looked like they were created by a kindergartner, or perhaps an unusually talented chimp.  I'm not very artistic, and improvement was slow, but I've gradually gotten to the point where I can turn out a decent-looking piece of pottery.

One of my better efforts

My first pottery teacher told us, "Never get attached to a piece until it's cool, in your hands, after the final firing."  It's good advice.  There are a million things that can go wrong.  After the piece is thrown, it still needs to be trimmed (removing excess clay at the bottom and finishing the shaping), have any modifications added (such as the spout and handle on the pitcher in the photograph).  Then it needs to dry -- without cracking.  (Cracks usually happen because the piece dried too fast or else unevenly, often when it has thicker walls at the bottom -- a common amateur mistake.)  Then it has to be "bisque fired," converting the raw clay to ceramic, usually at a temperature of about 1000 C.  Then it's cooled, and (most often) coated with a glaze to make it both attractive and water-tight, and re-fired at a higher temperature (depending on the clay and glaze used, between 1200 and 1400 C).  At every stage, the piece can crack, warp, or sag.  The glaze can malfunction in innumerable ways, including forming blisters or pock marks, pulling away from the clay (crawling), splintering as it cools (shivering), or even adhering to the clay and then shrinking and triggering spiral cracks (dunting).

Or, as happens all too often, you can just take the piece out and think, "why did I glaze it this way?  This looks like crap."

But every once in a while, all the stars align, and you get a piece that's really nice.

My favorite coffee mug

The reason all this comes up is a new study in Nature Human Behavior that looked at two interesting things: first, how far back the tradition of pottery-making goes; and second, once it arose, how quickly it spread.  The earliest pots known come from about 16,000 years ago in China and Japan, but after that it very quickly spread amongst the hunter-gatherer societies, and by 10,000 years ago it was found throughout the Near East and Europe.  (Pottery-making in Africa and the Americas is thought to have had an independent origin, but showed up around the same time.)

The authors write:

Human history has been shaped by global dispersals of technologies, although understanding of what enabled these processes is limited. Here, we explore the behavioural mechanisms that led to the emergence of pottery among hunter-gatherer communities in Europe during the mid-Holocene.  Through radiocarbon dating, we propose this dispersal occurred at a far faster rate than previously thought.  Chemical characterization of organic residues shows that European hunter-gatherer pottery had a function structured around regional culinary practices rather than environmental factors.  Analysis of the forms, decoration and technological choices suggests that knowledge of pottery spread through a process of cultural transmission.  We demonstrate a correlation between the physical properties of pots and how they were used, reflecting social traditions inherited by successive generations of hunter-gatherers.  Taken together the evidence supports kinship-driven, super-regional communication networks that existed long before other major innovations such as agriculture, writing, urbanism or metallurgy.

What blows me away about all this is that -- as I said earlier -- pottery-making ain't easy, and that goes double if you don't have modern technology to help.  First, you have to find a source of usable clay, which is by itself not simple.  Clays, depending on their chemical composition, fuse and turn into ceramic at different temperatures; an iron-rich earthenware, such as the clays used by the amazing potter Lucy Martinez, of the San Ildefonso Pueblo community, fire to a much lower temperature than kaolin-rich fine-grained clay of the type used in the classic Jingdezhen porcelains.  Fire a piece made from earthenware clay to the temperature used for porcelain, and it will simply melt into a puddle all over your kiln shelf.

Then there's learning which materials to use as glazes.  Our ancestors didn't have the refined glazes in plastic bottles that I use; they had to learn which naturally-occurring minerals would melt and coat the surface.  Not only did they have to concern themselves with coverage and water-tightness, they had to learn -- the hard way -- about safety.  Many of the prettiest glazes contain such dangerous heavy metals as cobalt, barium, and lead, and using vessels with those glazes for cooking or serving food could be downright dangerous.  (Now, chemists have done extensive testing on glazes to determine whether they're "food safe;" lead and barium have been almost entirely eliminated, and cobalt formulated so it stays put in the glazed surface and doesn't leach into your bowl of soup.  Fortunately for potters, because cobalt is an essential ingredient for just about all beautiful blue glazes.)

So what's amazing is that our ancestors learned all this by trial-and-error.  No wonder that after that -- as the researchers found -- the technology spread like wildfire.  Everyone would want to learn something that useful.

It's cool that in these days of mass production there are still people who want to learn this ancient skill.  Maybe today, with our electric wheels and factory-processed clays and bottled, tested glazes, we've got it easy compared to our forebears, but we are still using the same skills of shaping and refining and decorating that were developed ten thousand years ago.  When I get on the wheel to make a serving bowl or a coffee mug or a pitcher, I'm working in a medium that links me, in an unbroken line, back to nomadic hunter-gatherers who discovered that with little more than natural materials, a hot enough fire, and a pair of strong hands, you could make something that would last for millennia.

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The fingerprints of a slaughter

During the reign of Augustus Caesar, the Roman leadership felt very close to all-powerful.

They had enjoyed unbridled expansion into what is now France and Spain, the Near East, and North Africa.  The Roman legions were well-trained, disciplined, and powerful, led by ruthless men chosen because of their knowledge of strategy.  When they launched campaigns northward, against the Germanic tribes who lived in what is now Austria, Germany, Denmark, and the Netherlands, it seemed like it was only a matter of time before just about all of Europe came under Roman sway.

That all came to a screeching halt in the year 9 C.E.

I'd heard about the overwhelming defeat of the 17th, 18th, and 19th Legions near the village of Kalkriese, Germany in my college history classes, but I got a much better perspective on it last year when I read the wonderful book The Battle that Stopped Rome: Emperor Augustus, Arminius, and the Slaughter of the Legions in the Teutoberg Forest by Peter S. Wells.  The general gist is as follows.

Arminius (known in German as Armin or Hermann, but most historians use his Latin appellation of Arminius) was a chieftain of the Cherusci, a Germanic tribe who lived in northwestern Germany.  Arminius had been sent to Rome by his father, Segimerus (Sigimer), after the latter had agreed to become a vassal of the Roman Empire.  Many of the Cherusci resented this deeply -- Arminius amongst them.  But while he was in Rome, he played along, and learned a great deal about Roman military strategy, and eventually achieved Roman citizenship.

By trusting him, the Romans had sown the seeds of their own defeat.

Upon Segimerus's death, Arminius returned home to take up the chieftainship.  At the same time, the three legions that were charged with maintaining the peace in Germany were taken over by a brutal man named Publius Quinctilius Varus, whose harshness raised a great deal of ire amongst the Germanic people -- both those who were enemies and those who were nominally friendly.  Arminius became Varus's trusted advisor -- and used his knowledge to forge secret alliances with a number of other groups in the area.

The plans came together in autumn of the year 9 C.E.  The weather was turning bad, and Varus wanted to get his legions back to Rome before it became too difficult to travel.  What is especially ironic is that Arminius's uncle, Segestes, warned Varus the night before they decamped that Arminius was a traitor -- but Varus dismissed the warning as nothing more than a family feud and personal animosity at Arminius's popularity.

Arminius's training in strategy paid off.  He chose his site beautifully.  In the wooded hills near the modern town of Osnabrück, they entered a forest that was bounded by overgrown, thicketed hillsides on one side and a bog on the other.  This necessitated that they spread out -- by the time they were into Teutoberg Forest the legions were a long, straggling line over fifteen kilometers in length, hemmed in on both sides, with no easy place to mobilize defense and nowhere to run.

That's when Arminius sprang his trap.

All three of the legions were completely destroyed.  Varus himself survived, but the following day committed suicide in humiliation.  Total Roman losses in the debacle are estimated at between fifteen and twenty thousand.  A handful of men escaped -- or were allowed to escape -- to bring the news back to Augustus, who reportedly shouted, "Quinctili Vare, legiones redde!"  ("Quinctilius Varus, give me back my legions!")  It's said that Augustus never really recovered from the shock of the defeat; it certainly put an end to any serious attempt to recapture German territory, and the Rhine River became the boundary between the Roman Empire and the uncontested lands of the Germanic tribes for decades.  Augustus himself died almost exactly five years later, disappointed to the end at how his campaign for European domination had come to a crashing halt.

The Teutoberg Forest today [Image licensed under the Creative Commons Nikater, Hermannsweg02, CC BY-SA 4.0]

A lot of Roman artifacts have been found near Kalkriese -- significantly, very few Germanic ones -- but it's difficult to date metal with any kind of precision.  But a recent study of some of the artifacts by a team from the German Mining Museum Bochum, Leibniz Research Museum for Geo-Resources, and the Varus Battle Museum has developed a technique that suggests a way to identify the provenance of metal goods, and has pinpointed the artifacts from Kalkriese as coming from the 17th, 18th, and 19th Legions.

Thus, relics of the famous Battle of Teutoberg Forest.

Each Roman legion came with its own set of metalworkers, and each of them created their tools using a slightly different recipe for making bronze and brass.  Using a mass spectrometer, the researchers were able to pinpoint the subtle fingerprint of each legion's spearpoints, knives, shield fittings, armor, and jewelry, and from comparing metal objects known to come from the three "lost legions," they identified the articles from Kalkriese as remnants of one of the most famous battles ever fought.

"In this way, we can allocate a legion-specific metallurgical fingerprint, for which we know the camp locations at which they were stationed," said Annika Diekmann, one of the co-authors of the study.  "We find that the finds from Dangstetten [where the 19th Legion was stationed prior to their destruction in the battle] and Kalkriese show significant similarities.  The finds that come from legion sites whose legions did not perish in the battle, differ significantly from the finds from Kalkriese."

It's fascinating that we now have a way of identifying archaeological artifacts that are non-organic, where such techniques as carbon dating don't work.  What is now a quiet, peaceful forest was once the site of unimaginable bloodshed, in a battle that altered the course of history.  Looking at these objects brings home the impact of this victory on the Germans; Arminius is still considered a national hero, and the imperial ambitions of Rome were changed forever.  

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The clothing department

Mark Twain quipped, "Clothes make the man.  Naked people have little or no influence on society."

Given the fact that most of us are clothed most of the time, it's easy to lose sight of how odd it is.  We're one of the only species that covers our bodies -- the only others I can think of offhand are hermit crabs and caddisfly larvae.  In the climate where I live, of course, a lot of it is necessity.  For nine months of the year, we get temperatures that would be pretty uncomfortable if we weren't dressed warmly; for six of those months, if I ran around naked I'd risk freezing off body parts I still occasionally have a use for.

Even when it's warm, though, just about all of us wear some kind of body covering, for the sake of adornment, propriety, or (usually) both.  It's a custom in just about every culture on Earth.

But how long has this been going on?  Its ubiquity speaks to its antiquity; something shared by almost everyone is probably either highly important, or else very old.  (Once again, probably both.)  When we picture our distant ancestors, we usually think of them in furs and skins:

Gary Larson's cavemen aside, when did humans first start wearing clothes?

Some new research on fossils in Germany suggests it might be a lot longer ago than we realized -- perhaps as much as 300,000 years.

Archaeologists studying bones of cave bears (Ursus speleus) near the town of Schöningen found knife marks on the phalanges, metacarpals, and metatarsals -- the bones of the paws.  When butchering an animal for meat, the paws are usually ignored; there is little meat there, so the effort just isn't worth it.  The archaeologists studying the site claim that this is evidence that the men and women who cut up the unfortunate bears whose remains are at the site were after something else -- fur.

"The study is significant because we know relatively little about how humans in the deep past were protecting themselves from the elements," said Ivo Verheijen of the University of Tübingen, co-author of the study, which appeared two weeks ago in The Journal of Human Evolution.  "From this early time period, there is only a handful of sites that show evidence of bear skinning, with Schöningen providing the most complete picture.  We found the cutmarks on elements of the hands/feet where very little meat or fat is present on the bones, which argues against the cutmarks originating from the butchering of the animal.  On the contrary, in these locations, the skin is much closer to the bones, which makes marking the bone inevitable when skinning an animal."

The skins could have been used as clothing, but also might have been bedding.  The earliest evidence of sewing -- eyed needles -- comes from about 45,000 years ago.

So the discovery in Germany doesn't cinch down our ancestors from 300,000 years ago as being clothes-wearers, but it does mean they were aware of the use of animal pelts for something.  And given how cold it was back then, it'd be surprising that they didn't go pretty quickly from "This is comfy to sleep on" to "I could stay a hell of a lot warmer if I draped this around myself."

One thing I've always wondered is how we've become the only animals that have any sense of modesty about certain body parts, which (after all) we all have in some fashion or another.  It's one of those things that seems perfectly reasonable until you start thinking about it.  Customs do vary from place to place, of course; when we were in Denmark in summer, we saw women sunbathing topless, and nobody batted an eyelash.  In America, that'd cause some serious freakouts, and probably arrests for indecent exposure, even though guys can run around shirtless all they want.  And as far as the parts farther down, just about all cultures have a taboo against exposing those.

It's odd.

In any case, wherever our sense of modesty comes from, it seems to be very, very old.  And given that behaviors don't fossilize, it's likely that we'll never know the full story.  But it looks like Gary Larson's visions of cave men and women wearing pelts might not be all that far off.

Although I doubt seriously whether they held spelling bees.

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Lights in the sky

In March of 2022, dozens of people saw a UFO near the town of Lygurio, Greece.  The apparition has yet to be explained.

Lygurio is in the eastern Peloponnese, in a wooded region at the foot of Mt. Arachnaion.  It only has 2,500 inhabitants, but its scenic beauty and the proximity to the ancient Sanctuary of Asclepius attracts a good many tourists every year.  It's a rural area, far enough from Athens that it's mostly the quiet home of olive growers and vineyard owners.

The UFO was seen by many people in the village, but the best account comes from a man named Christos Tarsinos and his fifteen-year-old son.  Their story was corroborated over and over by others who had witnessed the mysterious occurrence.

"They were six bright lights," Tarsinos said.  "At first we thought it was a military helicopter, but it just flew meters above our car without wind or making any type of noise.  It was silent."

After a few minutes of watching, they saw the light rise and hover over some nearby houses.  "It was a bright tube of light," Tarsinos said.  "It appeared to shine down on the houses for a minute or two, as if looking for something.  The lights were low, about fifteen or twenty meters or so above the roofs.  They then moved down towards the old abandoned quarry.  The UFO, or whatever it was, hovered above the quarry for a few more minutes."

At that point, his view was obstructed by nearby hills and trees.

"We couldn’t see the lights anymore but we could hear them doing something.  A loud mechanical sound started to come from behind those hills.  It sounded like some type of hammering or drilling… it was mechanical in nature, I can tell you that."

Tarsinos's son asked what it was, and the father had to admit he had no idea.

"I told my dad that it was too big to be a drone, and I knew it wasn’t a helicopter," his son said.  "They were so bright and scary.  The lights were different colors.  The first two were red, the second two were white, and the last pair were greenish in color...  It was so bright, we couldn’t see our hands in front of us.  I thought we were going to die."

Several witnesses took photographs on their phones, but the quality is poor -- all they show is a scene at night and some glowing lights on the horizon of a hill in the distance.  (If you want to see the photographs, go to the link provided, but be aware they're nothing to write home about.)

Police investigated, and while a dozen witnesses who had been out on the road all said pretty much the same thing about the floating lights, interestingly none of the inhabitants of the village who were home at the time noticed anything amiss during the time when Tarsinos's "bright tube of light" was scanning the houses.  Myself, if a UFO sent a brilliant beam of light down toward my house at night, I think I'd notice.  Or at least my dogs would.  Someone would.

So, what are we to make of this?

The story is certainly suggestive, and the fact that we don't have the usual UFO situation of a lone observer in the middle of nowhere lends credence to the claim that the people in Lygurio saw something.  In other words, it isn't just a hoax.  But what was it?

The fact is, we have next to nothing to go on.  The poor quality of the photographs isn't really that surprising; phones take notoriously bad shots in dim light unless you know what you're doing to compensate.  But a couple of distant lights in an otherwise black photograph doesn't really prove anything.

As far as the eyewitness testimony, I'm in agreement with astrophysicist Neil deGrasse Tyson; "In science, we need more than 'you saw it.'  Eyewitness accounts, by themselves, do not meet the minimum standard of evidence a scientist needs to support any kind of conclusion."

It's unfortunate, but in the many accounts of UFO sightings I've read, not one has reached that minimum standard -- hard evidence, of the kind that can be studied in the lab, of something of alien manufacture.  Now, understand that I'm not saying that none of the thousands of UFO sightings could possibly be alien spacecraft; there are a good many that have defied conventional explanation, and I'm also in agreement with physicist Michio Kaku that if even one percent of sightings cannot be accounted for, that one percent is well worth studying.

So, it could be that what Christos Tarsinos, his son, and a dozen other witnesses in Greece saw that night was a visitor from another planet.  But "it could be" is a far cry from "therefore it is one."

The whole incident, as curious as it is, can be summed up by another quote from the eminent Dr. Tyson: "Remember what the 'U' in 'UFO' stands for.  It stands for 'unidentified.'  Well, if it's 'unidentified,' that's where the conversation stops.  You don't go on to say 'therefore it must be' anything."

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Voices and faces

I've blogged before about my difficulties with prosopagnosia (better known as "face blindness").  My ability to recognize faces is damn near nonexistent; when I do recognize someone, it's either through context or because I remember a specific feature or features (she's the woman with the blonde hair, green eyes, and lots of freckles; he's the guy with curly gray hair and a little scar on the forehead; and so forth).  This, of course, backfires badly when someone changes their appearance.  It's why I have an extremely poor track record of recognizing actors in unexpected roles, where makeup and costumes can dramatically change what distinctive features they may have.  I was absolutely flattened when I found out that Jim the Vampire in What We Do In the Shadows was played by none other than Mark Hamill, and that Peter Davison -- the Fifth Doctor in Doctor Who, a show I'm absolutely obsessed with -- played the suave French teacher Mr. Clayton in Miranda.

When I figure it out, it's often because the actor has a distinctive voice that even being in a different character can't quite hide.  I know British actress Zoë Wanamaker from three very different roles -- Quidditch instructor Madam Hooch in Harry Potter, the scheming Lady Cassandra in Doctor Who, and hapless mystery writer Ariadne Oliver in Agatha Christie's Poirot.  But in each role, she keeps a very distinct clipped, staccato cadence in her voice that, for me, is instantly recognizable.

So I'm above average at voice recognition, whereas I can't form mental images of faces at all.  Hell, sitting here right now, I can't picture my own face.  I know I have sandy blond hair, gray eyes, black plastic-framed glasses, and a narrow face, but it doesn't come together into any sort of image.  If I see a photograph of myself in a group shot, I often have a hard time finding myself, unless (1) I know where I was standing, (2) I recognize the shirt I'm wearing, or (3) there aren't any other skinny blond guys with glasses in the photo.

As I've mentioned before, to anyone local who is reading this; if I've walked past you on the streets of the village with a blank look, and not said hi, please don't take it personally.  I had no idea who you were, or that I'd ever seen you before.  I have no problem if you say hi and mention your name; in fact, I really appreciate it.  It's much less awkward to have someone say, "Hi, Gordon, it's Bill" than to have me standing there trying frantically to search for clues so I can figure out who I'm talking to, or worse, ignoring someone I actually like.

[Image licensed under the Creative Commons mikemacmarketing, Facial Recognition22, CC BY 2.0]

The reason this topic comes up is because of a puzzling piece of research in the Journal of Neurophysiology this week, that looked at the brain firing patterns in people when they heard famous people speaking (they used the voices of Barack Obama, George W. Bush, and Bill Clinton).  The test subjects were epileptic -- such studies often use epileptic volunteers who already have electrodes implanted in their brains to monitor their seizures, and the same technology can be used to study their other brain responses -- but were not prosopagnosic. 

The reason I say the research was puzzling is they found that very same part of the brain that seems to be miswired in prosopagnosia, the fusiform gyrus of the basal temporal lobe, was extremely active during the volunteers' attempts to identify voices.  Put a different way, the face-responsive sites in the brain are also involved with vocal recognition.

How, then, does one of those responses go so badly wrong in people like me, and the other one is largely unimpaired?

The current research is preliminary; identifying the site in the brain where a response occurs is only the first step toward figuring out what exact pathway the firing sequence takes or how it's mediated.  The parts of the brain have a remarkable degree of functional overlap, and this is hardly the only example of two seemingly related abilities working in very different ways.  

In fact, I can think of another instance of this phenomenon from my own experience.  I have near-perfect recall for music; my wife calls it my "superpower."  I hear a melody a couple of times, and I pretty much have it for life, and if it's in the range of my instrument, I can play it for you.  My ability to remember text, though, is mediocre at best, the main reason I gave up on doing community theater -- memorizing lines was painfully difficult for me.  It's hard to imagine why two different examples of recall involving sound would be so dramatically different, but they are.

So here, there's obviously something going on in the fusiform gyrus in face-blind individuals that interferes with visual recognition and leaves vocal recognition largely unaffected.  It'd be interesting to look at the electrocorticography for prosopagnosic volunteers.  (To use the technique in the paper, though, they'd have to find face-blind people who were also epileptic and had surgical electrode implants, which would be a small subset of a small subset of a small subset of humanity.  Kind of limits the possibilities for volunteers.)

In any case, it's interesting research, and I'm curious to see where it will lead.  We're only at the beginning of understanding how our own brains work, and the next twenty years should see some significant strides toward the maxim engraved on the walls of the temple of the Oracle of Delphi -- γνῶθι σεαυτόν (know thyself).

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Completing the recipe

Last week, I wrote a piece on the peculiarities of Jupiter's moon Io -- surely one of the most inhospitable places in the Solar System, with hundreds of active volcanoes, lakes of liquid sulfur, and next to no atmosphere.  But there's a place even farther out from the warmth of the Sun that is one of our best candidates for an inhabited world -- and that's Saturn's icy moon Enceladus.

It's the sixth largest of Saturn's eighty-some-odd moons, and was discovered back in 1789 by astronomer William Herschel.  Little was known about it -- it appeared to be a single point of light in telescopes -- until the flybys of Voyager 1 and Voyager 2 in 1980 and 1981, respectively, and even more was learned by the close pass in 2005 by the Cassini spacecraft.  

One of Cassini's spectacular photographs of Enceladus [Image is in the Public Domain courtesy of NASA/JPL]

Enceladus, like Io, is an active world.  It has a thick crust mostly made of water ice, but there are "cryovolcanoes" -- basically enormous geysers -- that jet an estimated two hundred kilograms of water upward per second.  Some of it falls back to the surface as snow, but the rest is the primary contributor to Saturn's E ring, 

Where it gets even more interesting is that beneath the icy crust, there is an ocean of liquid water estimated to be ten kilometers deep (just a little shy of the depth of the Marianas Trench, the deepest spot in Earth's oceans).  Like Io's wild tectonic activity, the geysers of Enceladus are maintained primarily by tidal forces exerted by its host planet and the other moons.  But that's where any resemblance to Io ends.  Chemically, it could hardly be more different.  Analysis of the snow ejected by the cryovolcanoes of Enceladus found that dissolved in the water was ordinary salt (sodium chloride), with smaller amounts of ammonia, carbon dioxide, methane, sulfur dioxide, formaldehyde, and benzene.

What jumped out at scientists about this list is that these compounds contain just about everything you need to build the complex organic chemistry of a cell -- carbon, nitrogen, oxygen, hydrogen, and sulfur.  I say "just about" because one was missing, and it's an important one: phosphorus.  In life on Earth, phosphorus has two critical functions -- it forms the "linkers" that hold together the backbones of DNA and RNA, and it is part of the carrier group for energy transfer in the ubiquitous compound ATP.  (In vertebrates, it's also a vital part of our endoskeletons, but that's a more restricted function in a small subgroup of species.)

But just last month, a paper was presented at the annual meeting of the American Geophysical Union describing the research that finally found the missing ingredient.  There is phosphorus in Enceladus's ocean -- in fact, it seems to have a concentration thousands of times higher than in the oceans of Earth.

This is eye-opening because phosphorus is a nutrient that is rather hard to move around, as vegetable gardeners know.  If you buy commercial fertilizer, you'll find three numbers on the package separated by hyphens, the "N-P-K number" representing the percentage by mass of nitrogen, phosphorus, and potassium, respectively.  These three are often the "limiting nutrients" for plant growth -- the three necessary macronutrients that many soils lack in sufficient quantities to grow healthy crops.  And while the nitrogen and potassium components usually (depending on the formulation) "water in" when it rains and spread around to the roots of your vegetable plants, phosphorus is poorly soluble and tends to stay pretty much where you put it.

The fact that the snow on Enceladus has amounts of phosphorus a thousand times higher than the oceans of Earth must mean there is lots down there underneath the ice sheets.

This strongly boosts the likelihood that there's life down there as well.  Primitive life, undoubtedly; it's unlikely there are Enceladian whales swimming around under the ice.  But given how quickly microbial life evolved on Earth after its surface cooled and the oceans formed, I feel in my bones that there must be living things on Enceladus, given the fact that all the ingredients are there.  (The oceans on Earth formed on the order of 4.5 billion years ago, and the earliest life is likely to have begun on the order of four billion years ago; given a complete recipe of materials and an energy source, complex biochemistry seems to self-assemble with the greatest of ease.)

Maybe I'm being overly optimistic, but the discovery of phosphorus in the snows of Enceladus makes me even more certain that extraterrestrial life exists, and must be common in the universe.  If we can show that there are living things down there, on a mostly frozen moon 1.4 billion kilometers from the Sun, then it will show that life can occur almost anywhere -- as long as you have all the ingredients for the recipe.

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