Space Junk

A map of space debris from the European Space Operations Centre (via Universe Today):



From the New York Times, Feb. 11th, 2009:

Debris Spews Into Space After Satellites Collide

For decades, space experts have warned of orbits around the planet growing so crowded that two satellites might one day slam into one another, producing swarms of treacherous debris.

It happened Tuesday. And the whirling fragments could pose a threat to the International Space Station, orbiting 215 miles up with three astronauts on board, though officials said the risk was now small...

It happened some 490 miles above northern Siberia, at around noon Eastern time. Two communications satellites — one Russian, one American — cracked up in silent destruction. In the aftermath, military radars on the ground tracked large amounts of debris going into higher and lower orbits.

“Nothing to this extent” has ever happened before, Mr. Johnson said.

This is a serious and growing problem. You can imagine the worst-case scenario over the long term - that the swarm of junk surrounding Earth becomes so dense that it forms a sort of minefield such that no craft can go into orbit without a significant risk of collision; we will have encaged ourselves with our own debris. That's a remote possibility at this point, but if it came to pass, it wouldn't be the first time we managed to junk a pristine and seemingly limitless environment with our crap.

Visualizing Segregation

That Mondrianesque image on the right there is, believe it or not, a sort of "map." It comes from some folks at Dartmouth who were interested in studying patterns of segregation in cities - not Jim Crow-era forced segregation, but the de facto kind that exists today in most American cities, where the phenomena of "black" neighborhoods and "white" neighborhoods are common. This map is going to need a bit of explaining, but bear with me, because I think it's really interesting.

The map is of a simulated city of "reds" and "blues." As the site describes it:

This segregation applet simulates the movement of people between houses within a "city." The city is divided into 10 x 10 "tracts" which are in turn divided into a grid of smaller squares. Each small square in the city represents a house that can be vacant (white) or occupied by a red or blue or, in three-color mode, a green square.

So the whole grid represents a city made up of people of two races. By pressing the start button on the applet you can set time in motion and let people move around, just as they do in real cities.

However, they're not moving around randomly. See those little boxes on the left that say "minimum # of like neighbors" and "maximum # of unlike neighbors"? Those determine where a given "family" will move to. In the image above there are no preferences, so any family will move anywhere. When you set time in motion, there will just be random movement of blues and reds around the grid. But suppose we change the settings to this:

Now we've set it so that a red family will only move to a neighborhood where it has a minimum of 4 red neighbors and a maximum of 6 blue neighbors; likewise, a blue family will only move to a neighborhood that has a minimum of 4 blue neighbors and a maximum of 6 red neighbors. And what's the result? After about 2,000 "moves," we get a city that looks something like this:

Now almost everyone in the city lives in a neighborhood that is completely homogeneous. This is sort of remarkable: remember, it's not the individual preference of anyone in this city to live in an all-red or all-blue neighborhood; everyone just wants to live in an area where at least half of the neighbors are the same race as themselves. But the end result is that nearly everyone ends up living in an almost totally segregated neighborhood.

Here's another scenario. In this case, the preferences are set quite liberally: every red only wants to have at least 2 red neighbors and no more than 6 blue neighbors, and every blue wants at least 2 blue neighbors and no more than 6 red neighbors. In this case, you can imagine, we have a city with low levels of racism and racial resentment and fear, but people just want to feel like they have at least a couple of neighbors who come from a similar culture or background as themselves. And here's what happens:

Shocking, right? Even though we've posited a city with very little racial animus, and just a seemingly reasonable desire of most people to feel like they share a similar identity or culture or background with just a couple of their neighbors, we still end up with a city where most people live in a generally homogeneous neighborhood. It's a fascinating result. There's a bit more mixing than in the scenario above, but still not as much as you might expect; maybe this comes closest to resembling an actual typical American city.

On one hand, this is sort of reassuring. It means that, even though many cities are still quite segregated, even in the 21st century, that doesn't mean different races are irreconcilably hostile towards each other; people just have a reasonable desire to be around at least a few people similar to themselves. On the other hand, if the end result of this desire is such a significant degree of segregation, then the odds that people would become more comfortable with other races through familiarity with them would seem not to improve over time.

By the way, the site also provides specific stats - those "segregation indices" on the left - for the more quantificationally adept (though that ain't me). You can also play around with different scenarios by changing the relative population sizes of the reds and blues, adding a third race ("greens"), or even instituting 1950s-style policies of restricting races from a particular area. For a certain sort of brain, it can be a bit addictive.

Jasper Johns' 'Map'

This is Map, a 1961 painting by Jasper Johns, the artist who's probably best known for his iconic representations of the American flag.

I'm not really a big Johns fan, usually, but I like this painting more than most of his stuff. For one thing: it's a map. But besides that, there are a lot of tensions in this work that make it interesting. Like, for instance, the map he's chosen to represent is both iconic and very banal. It's your standard grade-school "These United States" 50-state map that we all resented having to stare at as kids (or that some of us only got interested in when we noticed that there were fascinating little inset maps of population density or what have you in the corner, and which impelled us to go searching out what other interesting sorts of information about the world could be conveyed in maps, which would eventually lead us to start a blog on that very arcane topic some decades later). But of course he's completely slathered over that banality with these really dramatic abstract expressionist gestures, some really bold colors and a lot of dynamic tension between those elements that is, in a word, fun (though also strongly ambivalent: some of those painterly gestures seem almost sneering, even angry). The effect, in my opinion, is that Johns' Map does something that a conventional 50-state map cannot, namely: it says something about our relation to the represented object. That is, our country, and the emotional relationship we have to our country (and of course this goes for citizens of any country in the world) is a huge, messy, incomprehensible thing, which inspires all manner of conflicting passions. That's something that the cold geometry of a conventional map can't capture. But this map, which is especially vibrant, even by expressionist standards, reveals something of that complex web of feelings.

Think of it this way: I think most of us, when we hold an abstract concept in our minds like "America" or "my country," have a visual image of something like a map of the US; but the sort of maps we're used to seeing convey nothing of the emotional content of those abstract concepts, which are indeed among the most potent concepts we have, right up there with "family" and "god." Johns' map is, I think, an attempt to evoke something of that emotional content, to give us a mental image that's commesurate with the concept's punumbra of feeling. It is actually, if you think about it, a rather patriotic thing to do.

Ice Age Climate Map

That earlier post on human migration got me curious about the climate of the ice age. What sort of a world were our ancestors encountering as they spread inexorably around the world? Earth was in a glacial period for most of the time during which the expansion of our species occurred; the current interglacial period we all know and love didn't set in until after humans had colonized every continent (every decent continent, at least - sorry, Antarctica). So what was the world like for those prehistoric peregrinators?

Ask Wikipedia, and ye shall receive:



(You'll have to click on the map or follow the link to be able to read the legend.) This is a standard-issue vegetation map of the sort that always show up in the first section of world atlases, but it shows the world as it was ca. 18,000 years ago. And things were shockingly different. For instance:

-That purple in the eastern US indicates taiga, the coniferous forests which today are found right at the limit of the Arctic tree line in northern Canada. Apparently the Mississippi Delta of 18,000 years ago resembled the Yukon of today.

-Florida was a semi-arid temperate woodland, and the Atlantic coast of the US was boreal forest. Anything north of New York City and Chicago was under ice altogether.

-Much of Europe was under ice as well, and steppe-tundra extended all the way down to the Mediterranean coast. Tundra also had a foothold in the interior of the Iberian Peninsula.

-Interestingly, there were tropical forests and grasslands in many of the same areas as there are today. But the temperate regions really get pinched; it seems that between the subtropical deserts (also in most of the same regions as today) and the ice and tundra of the higher latitudes, there just wasn't much room for the expansive temperate forests which have more recently been characteristic of North America and Eurasia, especially. It seems that the world of 18,000 years ago just had a lot fewer trees.

-Australia? 'Bout the same, maybe a little chillier. The Southern Hemisphere in general, in fact, seems to have been less affected by the last period of glaciation.

Given all this, you can well imagine why humans spread first along the coast of the Indian Ocean, all the way to Australia: pretty much everything north of there was barren, windswept, and cold. It was the North Dakotafication of the world. In fact, as those first bands of humans finally left the amniotic comforts of southern Asia and Africa and soldiered into the frozen lands to the north, an interesting question to ask them would have been: why?

Destruction in Gaza

The BBC published this map of the recent conflict between Israel and Palestinians in the Gaza Strip. During the fighting, 13 Israelis were killed by rocket attacks, while more than a thousand Palestinians died in the Israeli response. The red squares mark destroyed buildings.

Human Migration

I like this map of the spread of humans across the planet.



The projection (some kind of oblique mercator?) [UPDATE: it's a Dymaxion map, apparently.] makes the course of human migration seem like the natural consequence of the spatial relationships between the continents - which of course is just what it was. (It also makes the hypothesized route to North America actually seem like easily the most sensible way to get from Europe to the New World, though I don't know what that dashed line is indicating; it seems to be suggesting that Europeans were emigrating to eastern Greenland during the Stone Age, but I've never heard of such a thing.)

The blue hatchmarked lines indicate the extent of ice and tundra during the last ice age. The numbers are thousand of years before the present, and the corresponding colored arcs on the map indicate the spread of humans at those times. According to this map, migration was most rapid through ice-free southern Asia. People actually arrived in Australia before they ever made it to Europe, which climatically was not nearly as rosy as it is today. It took still longer to make it to northeastern Asia, and then the Western Hemisphere was the last area to become populated when a land bridge allowed people to cross over from Asia.

The letters indicate mitochondrial DNA haplogroups. If they mean something to you, then bully. If not, I'm afraid I'm not qualified to explain them. I do like the map's pretty colors, though.

Australia Fires

Via Jeff Masters, here's a satellite image of the plumes of smoke from the fire areas of southeastern Australia.



Says Masters:

It is difficult to imagine more hellish fire conditions than those observed in Victoria state's capital, Melbourne, on Saturday (February 7). The temperature soared to 115°F (46.4°C), the hottest ever recorded in the city, besting the previous record of 114°F (45.6°C) set on January 13, 1939. Humidities as low as 4% and sustained north winds that reached 43 mph, gusting to 51 mph, accompanied the furnace-like heat. The dry winds were easily able to fan fires in the parched vegetation. Severe drought conditions reign in Southeast Australia, where some regions--including the city of Melbourne--have experienced their worst drought on record over the past eight years.

More than 170 people have died in the fires so far. The weather events that allowed the conflagrations to flourish - including drought and high temperatures - are consistent with those predicted by most climate models that anticipate significant global warming.

The Football Map of the World

If, unlike me, you're an avid follower of the world's most popular game, you'll appreciate this: footiemap.com has maps that show the locations of the major teams in all the big footballing countries, from England to Argentina - as well as many of the sport's lesser powers, such as the Faroe Islands and the United States. It leaves a lot to be desired in terms of layout and user-friendliness (it's inconveniently unzoomable), but for a sport that seems to engender a lot of cross-border fan interest, it can be useful.

Aston Villa: where the hell is it?

Place of the Week: Shibam, Yemen

Time for another entry in the surprisingly labor-intensive series with the still undetermined future, Place of the Week. This time it's Shibam, Yemen.



Status: town and former capital of the Hadramawt Kingdom
Population: 7,000ish
Age in years: 2,000ish
Number of medieval skyscrapers: about 500

Shibam is a walled city in the Yemeni desert that is famous for its mud brick high-rises. There are hundreds of such towers that are five to eleven stories high which were among the tallest in the history of the world when they were first built in the 16th Century. The architecture, which was orinigally developed as a defense against Bedouin attacks, has had the unintended consequence of making the town look really, really cool.

Of the town's architecture, Wikipedia says:

Shibam is often called "the oldest skyscraper-city in the world" or "Manhattan of the desert", and is the earliest example of urban planning based on the principle of vertical construction. The city has the tallest mud buildings in the world, with some of them being over 100 feet (over 30 meters) high, thus being the first high-rise (which need to be at least 75 feet or 23 meters) apartment buildings and tower blocks (except perhaps for the insulae of ancient Rome). The tallest building in the city is the mudbrick minaret which stands at 175 feet (over 53 metres) tall.

The city itself actually dates back to the 100s CE or so. It was intermittently the capital of the Hadramawt, a loose confederation of sultanates and emirates that extended (and extends today in the form of the Hadramawt Governate) from the southeastern coastal plain of Yemen into the Jol, the broad 4,500 ft. plateau in the Yemeni interior, and slopes down into the essentially uninhabited and liminally vague Empty Quarter. The climate is deserty, with occasionaly strong storms in April and September. Here's a link to the Shibam Urban Development Project, which exists to preserve the cultural heritage and promote sustainable economic development of the place, and has more information about the city.

I believe I would like to visit this place some day.

Political Identification in the US

Last week, the Gallup polling agency came out with a new survey of political identification in all 50 US states. Here are the results:



It's a Democratic blowout. Democrats have an advantage in 35 states, Republicans in only 5. Democrats lead in each of the 22 largest states, and 31 of the 32 largest. It's such a severe blowout, in fact, that I am inclined to take it with a grain of salt. After all, it's a survey of all adults, rather than just registered voters, and adults as a whole tend to lean more Democratic than the actual electorate. Plus, this surely includes a lot of southern white Democrats, who often vote Republican. But Paul Rosenberg compared this 2008 data to a similar survey Gallup did in 2002, and the contrast is striking:



Two points. Number one: Gallup's design sense has improved drastically. Number two: the country is undeniably way more Democratic than it was in 2002. There's obviously been a big shift in the politics of the US since the days of terror alerts and mushroom-cloud smoking guns.

Accessibility and Wilderness

A measure of remoteness (previously discussed at The Map Room):




This map, put together by the World Bank and the European Commission, depicts the distance of every point on the globe from the nearest large city. Specifically, it shows travel time - in hours and days, as per the legend - from any cities of 50,000 or more people.

An inset on the discussion of the map asks, "Wilderness? Only 10% of the land area is remote – more than 48 hours from a large city." Considering that only a couple hundred years ago, we were bopping around, still looking for (and finding!) new continents, that's pretty remarkable. And there's definitely something bittersweet about it; there's something to be said for the romantic desire for there to be unexplored territory, an edge of the map beyond which there is only the unknown. Nowadays it's possible to scan the peaks of Tibet and the islands of the South Pacific on Google Earth, and spend only a moment 'flying' from one to the other. That's pretty cool, but it's another one of those hugely wonderful things about modern life that comes at a huge cost.

Not that the entire world is an inextricable web of interconnectedness, at least not quite yet. The photo at the right was taken just last year; it's an image of members of an un- contacted tribe deep in the Amazon. It's strange and gripping image. But there's a poignancy to the photograph that isn't just a function of the exotic nature of the encounter; it's the sense that something is being recorded just as it is vanishing from Earth and from history. The wilderness depicted here, and the humans who inhabit it, are seen from the perspective of a plane, an icon of technological power and control; the effect is to render those tribespeople exhibits in a zoo. When nearly the entire world is just a baggage check and a cab ride away, that's what wilderness becomes - something to snap photos of from the window of a plane of the deck of a cruise ship.

But of course, the whole romantic impulse that wants wilderness to be more than that is probably mostly just a product of wilderness no longer being that. In other words, when wilderness was real and immediate, it was terrifying, dangerous - something you had to make sacrificies to or ask mercy of. It's only due to its safe, contained quality - its zooification - that it becomes something abstract, an idealized object of nostalgia. And then there are all the benefits that come from an accessible world: the ability to see all of it, for one thing, and to meet people from all over the world.

And increasingly important, maybe, is that accessibility causes us to re-calibrate our sense of the scale of the world. For all intents and purposes, until the satellite era the world seemed basically limitless and bountiful beyond measure. I think. I wasn't around then, but that seems to be the way everyone always talked about it, until images like this one started popping up in the public consciousness. When your frame of reference shifts from the earthbound and the limitless horizon, beyond which there is always more, to a view of the earth as a sphere, an object with limits, then you've probably met at least the first necessary condition for moving towards making the planet a sustainable home, because it's the first necessary condition for acknowledging that there might be limits to the sustainability of civilization. That latter frame of reference is growing increasingly prominent in our conception of the world we live in, and it's a way of seeing the world that wouldn't be possible but for the very sorts of technological change that have caused wilderness to recede into something safe and remote, and almost mythical, in the first place.

Air Traffic

Awesome. This video shows every flight in the world over a 24-hour period.


Strangely sublime.

The Greatest Journeys Ever

This is fun. The folks at Good Magazine have put together an interactive map of some of the greatest voyages in history.



Magellan and Columbus and Marco Polo are all on there. But so are Ken Kesey's Electric Kool-Aid Acid trip, Jack Kerouac's route from On the Road, and the Pequod's voyage in Moby Dick. You can select a voyage and click through slideshows to see, for instance that Ken Kesey and the Beats sort of didn't get along, or that Captain Cook was on secret orders to claim any new continents he might happen to stumble upon for England. Or that Pizarro was a real asshole. That sort of thing.


One of history's great trips.

The Genetic Map of Europe

Speaking of genetic variation in Europe, this map by Manfred Kayser and others is fascinating.



It's a bit hard to read at first. (You can click on it to see a bigger version.) The basic idea is to show the genetic relationships between 23 distinct populations across Europe, which are physically located as indicated on the right. So the more populations overlap, or the closer they are to each other, the more genetically similar they are.

The genetic map is also configured to roughly correspond to the physical relationships between the populations. One thing you can see is that they are more spread out along the top-bottom axis than along the left-right axis. That means there's greater genetic variation between north and south than there is between east and west.

The fascinating thing is how the history of Europe can be read in these patterns. From the New York Times write-up of the paper:

Europe has been colonized three times in the distant past, always from the south. Some 45,000 years ago the first modern humans entered Europe from the south. The glaciers returned around 20,000 years ago and the second colonization occurred about 17,000 years ago by people returning from southern refuges. The third invasion was that of farmers bringing the new agricultural technology from the Near East around 10,000 years ago.

The pattern of genetic differences among present day Europeans probably reflects the impact of these three ancient migrations, Dr. Kayser said.

It makes sense that latitudinal genetic variation would be greater than longitudinal variation. People accustomed to a certain climate - especially farmers - would be more likely to spread quickly along east-west lines, since places that have similar latitudes tend to have similar climates; people who are adapted to live at a given location are more likely to be comfortable 500 miles due east or west of that location than 500 miles due north or south. So it would take longer for populations to spread north or south, which would allow more time for genetic changes to emerge.

There are the Alps, too, of course. They run generally east-west, and serve to partially block the Italian peninsula from the rest of Europe. This relative isolation is probably why the Italian populations are among the most genetically peripheral in Europe.

And then there are the Finns. They don't even genetically overlap with other groups in the study, according the metric the authors are using - in fact, they're not even close; they're way off by themselves in the upper right-hand corner. According to the NYT, the genetic barrier between the Finns and the rest of Europe "arose because the Finnish population was at one time very small and then expanded, bearing the atypical genetics of its few founders."

The Lactose Tolerance Map of Europe

More European genetics! This was published in Nature. Don't worry about the top map. The middle one shows genetic diversity in the milk-producing genes of European cattle. The bottom one shows the geographic distribution of lactose tolerance in Europe. Darker shades of orange indicate greater diversity.

So why is this so interesting? Because the high level of genetic diversity in north-central European cattle is an indication that that's where cattle have been around the longest: that's the area where their genes have had the most time to diversify, like an old tree whose branches have had a lot of time to spread out. And see that dashed black line in the bottom map? That indicates the area where the fossil record shows that people have been herding cattle the longest. So the genetic record and the archaeological record really strongly agree: cattle have been around for a long time in north-central Europe and southern Scandinavia.

Now look at the bottom map - the one that shows lactose tolerance in the human population. Of course, all humans digest milk as babies. But it's only thanks to some relatively new genes that many of us are able to digest milk as adults. These are the genes that make us lactose tolerant. And where are those genes concentrated? In almost the exact same area as the oldest European cattle! In other words, Europeans have evolved to be able to drink milk in just those areas where that adaptation has been most advantageous.

Those original cattle herders - the Funnel Beaker culture - established themselves aroundd 5,000 to 6,000 years ago. So, as with skin color, we're not talking about a real long time in which these evolutionary changes have occurred. Nonetheless, the population today in The Netherlands and Sweden is more than 99% lactose tolerant.

Europe isn't even the only place lactose tolerance evolved. It's happened even more recently in Africa, among three distinct populations in Kenya and Tanzania, as well as Sudan, and as recently as 2,700 years ago. (No word on lactose tolerance in India, but given that they eat a lot of dairy and have had domesticated cows the longest, there's probably some interesting genetic history there as well.)

The Blue Eyes Map of Europe

And here is a map of the distribution of fair eyes in Europe.



It's a very - though not entirely - similar distribution to that of blonde hair. The concentration of these really sort of strange traits around the Baltic makes you realize that northern Europeans, and especially Swedes and Finns, are kind of a race of mutants. Not that there's anything wrong with that. But it makes you wonder why these adaptations never showed up on a large scale in northern Asia and northern North America. Those areas were certainly populated long enough for such traits to take root.

The Blonde Hair Map

Apropos the last post, here is a map of the distribution of blonde hair across Europe, via Strange Maps.



Any guesses as to where the "blonde gene" first cropped up?

By the way, I don't want to sully the Vikings' good name by implying that they may have been engaged in any lascivious behavior during their various rampages across Europe, but it's interesting to compare the blonde map with this map of Viking invasions.

The Skin Color Map

Do this, says NPR's Robert Krulwich:

point your elbow to the ceiling.

Then imagine yourself naked.

Then look at the patch of skin on the inside of your upper arm, the part of you that almost never sees the sun.

Whatever color you see there is what experts call your basic skin color, according to professor Nina Jablonski, head of the Penn State Department of Anthropology.

This map shows skin colors across the globe - the average colors that indigenous people would see if they did the upper arm test:



Humans tend to evolve towards lighter skin when they move toward the poles, and towards darker skin when they move towards the equator. Obviously, the process takes many generations - but apparently not as many generations as once thought:

Skin has changed color in human lineages much faster than scientists had previously supposed, even without intermarriage, Jablonski says. Recent developments in comparative genomics allow scientists to sample the DNA in modern humans.

By creating genetic "clocks," scientists can make fairly careful guesses about when particular groups became the color they are today. And with the help of paleontologists and anthropologists, scientists can go further: They can wind the clock back and see what colors these populations were going back tens of thousands of years, says Jablonski.

She says that for many families on the planet, if we look back only 100 or 200 generations (that's as few as 2,500 years), "almost all of us were in a different place and we had a different color."

That's kind of amazing. That's like going from black to white in the time between Socrates and ourselves. Evolutionarily? That's really fast. (It's interesting that every new finding about human evolutionary change seems to point towards it occurring faster than previously thought.)

Here's the link to the audio of the NPR story. Thanks to loyal reader camella and&also& kt for the tip.