Saturday, January 30, 2010

A unique mobile or two

kw: observations, art, photographs

A couple of random things have crossed my path. First, I am an aficionado of mobiles. I like to go see them (the Delaware Art Museum has a fine one by Calder, and it is nearby), and I occasionally make one. A unique mobile made of pine cones hangs in a music studio at Darlington Arts Center in Boothwyn, PA (AKA Garnet Valley).


But my pick for "even more unique" goes to this "mobile-mobile" in England, made of fifty mobile phones (which are called "mobiles" in England, rather than "cells" as here).


Here is a closeup. The installation is the work of James Theophane of London. The link (his blog) has lots of added material about the mobile-mobile.

Friday, January 29, 2010

The little planet that could

kw: book reviews, nonfiction, astronomy, planets

I miss Pluto. I learned the names of the nine planets when I was very young, and a few years later, with my father's help, built a 3" (76mm) diameter reflecting telescope from a kit. I still have it, and still use it. It is really too small to do much with the planets, but I've seen them all but Pluto—at 15th Magnitude, it is beyond the reach of any visual instrument smaller than 12.5" (320mm).

A little over three years ago, the International Astronomical Union (IAU) voted to approve a contentious proposal to refer to Pluto and a number of other small orbs as "dwarf planets", but not "real planets". Though the vote seemed a landslide, many were voting "Yes" just to put an end to the bickering. The minority in that vote is, however, vocal, dedicated, and not inclined to give up. And now one of their number, Alan Boyle, has written The Case for Pluto: How a Little Planet Made a Big Difference.

One big difference was that, during the time Pluto was still known as the Ninth Planet, the New Horizon mission was proposed, funded (plenty of back-and-forth there, though), and launched. Shortly before the launch five years ago, this image was taken with the Hubble Space Telescope. The astronomers were aiming for a good, up-to-date image of Pluto and Charon; the two littler moons were a bonus! This is a NASA image. Related images can be found here.

In his book, Dr. Boyle recounts the history, not just of Pluto, but of the larger non-naked-eye planets Uranus and Neptune also.

By the way, Uranus can be seen with the naked eye when it is in opposition, only from a very dark locale; you have to be young and know exactly where to look. It was never identified before telescopic discovery. It was apparently seen and charted a few times, but nobody connected the observations of an obscure 6th magnitude "star" that seemed to be gone the next time you looked for it. But it is an easy object with binoculars or a small telescope. Now, Neptune, well, that's hard with a 3-incher.

Another aside: why do I say you have to be young to see Uranus? After the age of 30 or 35, the eye's iris won't open bigger than 5 or 6mm diameter. It takes a full 7mm opening to see 6th magnitude objects.

Back to the book: the author also recounts in some detail how important the designation of Pluto as a planet has been to getting funding approved and finally appropriated for the New Horizons mission. This mission is seen as doubly important now that Pluto is recognized as the first-discovered of a new class of object, a member of the Kuiper Belt of icy-rocky bodies. A major class of these Trans-Neptunian Objects (TNO's) are being called Plutinos. This Wikipedia article is a comprehensive presentation of the TNO's and their kin.

Strictly speaking, Pluto is a Cis-Neptunian object; its orbit crosses inside that of Neptune. This, to me, is an important consideration regarding the definition adopted by the IAU which has two parts:
  1. A planet is round because its self-gravity is great enough to overcome the strength of the materials that compose it.
  2. A planet has dynamically cleared the area of its orbit of other bodies.
That second part is what got both Pluto and the asteroid Ceres excluded from being "Planets". Ceres dwells among the asteroids, which seem to cross its orbit with abandon, and Pluto not only dwells among many Plutinos (which share its 3:2 resonance with Neptune), but also in the vicinity of Neptune itself. Here's the kicker; Neptune hasn't cleared out the Plutinos, many of which cross its orbit (the Cis- ones), so is it also not a planet????

Furthermore, dynamical computer simulations of the early Solar system indicate that Jupiter did the clearing of the entire inner system, particularly Mercury's orbital vicinity, while gradually being pushed outward to its present orbit. We don't see that Mercury actually did the clearing job; so is it also not a planet????

Finally, bodies as large as Mars, or maybe larger, could lie at quite great distances, say 1000 AU (~150 billion km) or more. We'll see how detectable they might be in a moment. Almost by definition, the slow pace of things out there has prevented any orbit-clearing. How big must a body be to be a "real planet" at such distances?

Dr. Boyle makes a strong case for a different kind of look at the situation. The Solar System has three classes of spherical objects, other than the Sun:
  • Four rocky planets, which are all Sunward of the main asteroid belt.
  • Four gaseous giant planets, which are all beyond the main asteroid belt.
  • An unknown number of rocky/icy orbs (and you can include the larger moons of Earth, Jupiter and the other giants here), including Ceres, Vesta and Pluto, and now Eris (slightly larger than Pluto), Sedna, Makemake and others discovered very recently. By the IAU resolution, these are called "dwarf planets".
Other than the rocky four and the giant four, we now know that there are many, many of the self-gravitating spheres, and that poor, denigrated Pluto represents the majority consituency! At this point, no matter what "kind" of planet you designate Pluto, it is of critical importance as the first member of a very exciting class of object. We have as much to learn from them as we do from the larger bodies; indeed, concerning the early history of the Solar System, we have the most to learn from the more distant bodies.

While reading, I got interested in how one determines the parameters, the search space, of a distant object. With a little figuration, I got this much:
  • Velocity in a circular orbit is proportional to the inverse square root of the orbit's radius. This radius for Jupiter is 5.2 times that for Earth. 1/5.2 = 0.192; √0.192 = 0.4385; that times Ve (29.8 km/s) is 13.1 km/s, the measured orbital velocity of Jupiter.
  • Subtract a body's velocity from that of Earth and divide the result by the distance from Earth to the body. For bodies beyond Neptune, you can pretty much ignore the body's velocity, it is less than 18% of Earth's velocity. You can also come pretty close by taking the distance from the Sun; one AU out of thirty or more is pretty small. So for Neptune, 29.8 / 4.5 billion = 6.6x10-9
  • For such distant bodies, multiply by the number of seconds in an hour or a day, so you can get hourly or daily parallax. For Neptune, the daily parallax is 0.00057.
  • Take the arcsine of that: 0.033° in this instance, or 1.97 arcminutes or 118 arcsec.
For the "back edge" of the scattered disk, the tattered end of the Kuiper belt, R is about 150AU or 22.5 billion km. V = 2.4 km/s so let's ignore it. The daily Earth motion is 29.8x86,400 = 2.57 million km. Divide that by 150 AU to get 0.000114. Arcsin of that is 0.0066° or 0.39' or 24". That is quite large, so sets of images (we don't use glass plates any more) taken a day apart, looking for a "blink" of 24 arcseconds or greater can detect any Kuiper Belt Object.

How about brightness? If you are just looking for Pluto-size and larger, start with Pluto's Magnitude of 15 at a distance of 40 AU. Brightness decreases as the fourth power of distance (square once for the inverse-square law for sunlight, and square again for the apparent area of the object). At 150 AU we get (40/150)4 = 0.005. Turn that into magnitudes, and it adds 5.7, making a "back-edge" Pluto-sized KBO a 21st Magnitude object.

Modern telescopes can record objects as dim as Mv=30 or so. If we're generous to add ten magnitudes to our distant KBO, we figure thus: ten magnitudes is 1/10,000, and the fourth root of that is 10. So the most distant "Pluto" we might see would be 1,500 AU away. In addition, back at the "back edge", ten magnitudes figures out to a diameter ratio of 100, so a body as small as 15-20 km, anywhere in the KB, ought to be findable with current equipment! One way to make a body more detectable is to drive the telescope at its expected angular speed, just a whisker different from the siderial rotation of the sky. A body moving at that speed will be a point. This is most used for asteroid detection, but I suspect it is also being used for KBO's.

Now, many astronomers expect that there are larger bodies 'way out there. How far away could we see a Jupiter? At 40 AU Jupiter's magnitude would be 7. 31-7=24 magnitudes, which works out to brightness factor of 4 billion, whose fourth root is 251. 251x40 = 10,040, which puts such a body in the nearer parts of the Oort cloud.

At present, it takes exceptional equipment to reliably record a 31-Magnitude object. It will take the next generation of space telescopes to find the more distant ones. But equipment we have already is sufficient for finding thousands of dwarf planets beyond Neptune. The more of these we find, the more important Pluto becomes. Also, we gather more potential targets for New Horizons. We need to be looking now for KBO's beyond Pluto which will be well situated for observation by the spacecraft after it flies by Pluto and Charon, and heads into the rest of the Kuiper Belt.

It is currently moving at 18 km/s, in a region near Saturn where orbital velocities are less than half that. It'll still be moving above 10 km/s when it passes Pluto, but even at that rate, it will be in the 100-AU-wide Kuiper Belt for about fifty years.

So the way I see it, echoing the author, Pluto has been promoted. No longer the Ninth Planet, it is the First TNO, just as Ceres is now promoted to First TMO (Trans-Mars Object). Pluto, it is nice to have you back!

Thursday, January 28, 2010

Ecology of the Dinos

kw: book reviews, nonfiction, palaeontology, dinosaurs, ecology

I began reading this book before the one I reviewed two days ago, but got bogged down and set it aside while finishing that one. Dinosaur Odyssey: Fossil Threads in the Web of Life by Scott D. Sampson is a big book with a lot to say. Though there are copious illustrations, there is still a ton of text.

There are also a number of good ideas. Dr. Sampson dwells on the relationships among dinosaurs and with the plants and animals about them for about half the book. Some of his writing got me thinking along the lines I explored in yesterday's post.

I happened across the online article by Mike Taylor, Sauropods Held Their Necks Erect, which included this screen shot from Walking With Dinosaurs by the BBC. While the sauropods are shown here walking "horizontally", Taylor reasons that they used a posture more like a giraffe. With trees blocking one's view, it is likely one would see at most one or two small herds of sauropods at a time.

The first part of Dinosaur Odyssey goes over earth history, the geologic time scale, and other obligatory material for a book on the Mesozoic animals. I've read so many such treatments that I wound up skipping a lot. But I don't begrudge its presence; if this book is the first dinosaur book a precocious middle-schooler reads, the discussion will be helpful and necessary.

More than any other book I've read, though, this one details the ecological relationships of dinosaurs and their place in our history…and in our present: birds are dinosaurs, taxonomically. They continue the ecological success of creatures that dominated terrestrial landscapes for 160 million years—until the K-T extinction—and bring it forward another 65 million years to the present. Bird species outnumber mammal species two-to-one, and it was only after humans got into South America some 13,000 years ago that the reign of flightless "terror birds" as dominant large vertebrates came to an end.

The author makes an interesting case in favor of dinosaurs, at least some of them, being "mesothermic", not ectotherms like modern lizards, but not quite wholly endothermic like modern birds and mammals. Indeed, many bird species can regulate their body temperature downward to save energy when they can't feed. Hummingbirds do so at night, for example. Many birds do this, but very few mammals, and not as completely. There appear to me to be two styles of endothermy, which probably evolved separately.

Now, if dinosaurs were mesothermic, particularly the predatory ones, a given landscape could support more of them. A fully endothermic tyrannosaur, weighing as much as a large bull elephant, would need between twenty and fifty times the area to feed in as an elephant needs, because its energy supply is one step removed from the herbivory the elephant employs. It takes ten to twenty pounds of good-quality feed to produce one pound of cow or elephant; herbivorous dinosaurs were probably similar.

Also, it takes five to ten pounds of the herbivore's meat to yield one pound of predator. But day-to-day energy use depends on metabolism. Comparing two modern, similar-sized beasts: a well-fed lion can go two or three days until the next kill. A well-fed Komodo dragon can last a month. Thermal strategy dictates efficiency.

Bringing us the scenarios of dinosaur ecology requires weaving together, not just biological strands, but also palaeogeography and plate tectonics, the rise and fall of oceans, and even cosmology, for it was a cosmic event that killed all the dinosaur lineages except the birds.

The author closes the book with an epilogue, musing about using dinosaurs as a vehicle to better teach biology, ecology, evolution, and scientific principles in general. He also proposes them as the "poster children" for a grand story that teaches us better stewardship of the planet. He repeats what is well known in some circles, that we are in the midst of a human-driven great extinction that could be as severe as the one that ended the "age of Dinosaurs" and ushered in this mammal-dominated one (though remember there are twice as many birds). It doesn't have to be this way, but we seem to be like someone riding in a taxicab whose driver is drunk or insane, and the door won't open. Those of us who care haven't been able to do much about it. I hope a book like this can be a positive influence.

Wednesday, January 27, 2010

Mesozoic herds

kw: musings, dinosaurs, ecology

I am reading a book, not done yet, about dinosaurs and how they fit into the ecologies of their times. I'll make a couple observations while I am thinking of them.

When Charles Darwin visited Patagonia while voyaging on The Beagle, he observed a modern bone bed where two streams came together, and compared its seeming richness with a landscape containing scattered herbivores. He remarked about the concentrating effect of the rains washing corpses or skeletons of the animals together. We need only recall that, while a cow or llama may be able to live for ten, twenty, even thirty years, most live three or four years before disease or predation does them in. On a particular square mile of the prairie, it only takes one or two of the few dozen animals that die every year to wash into the stream bed, to produce a mighty bone pile in just a thousand years.

I have visited two semi-recent fossil bone beds, La Brea Tar Pit in Los Angeles, California, and the Mammoth Site near Hot Springs, South Dakota. Both of these were active as animal traps for thousands of years. I don't find it surprising that each has a few hundred mammoth skeletons; I find it surprising that there are not more of them. Most of the mammoths that died in the environs of these "traps" did not wind up in them. Yet they are considered marvels of fossil richness.

Consider an area such as Dinosaur National Monument (or, indeed, the entire Four Corners region), where animal remains were protected and fossilized over a span of a few million years. We need to remember that the animals found in them did not die all at once, but over the whole time span. There are really very, very few places of "mass killings". Where they do occur, we still find evidence that there was after-death concentration of remains, such as by fluvial gathering into stream beds or pools.

The really giant animals of the Mesozoic needed large ranges to support their feeding. In the grass-rich Badlands of South Dakota and Nebraska today, it takes fifty acres to support one 300 kg (650 lb) cow. If 50-ton sauropods were warm blooded, how many acres did each require? Several thousand? Even in richer grasslands such as in Iowa (pre-Corn), one would need ten acres per cow, and perhaps 1,500 per adult sauropod (that's over two square miles, or about ten square km).

But did sauropods have a similar energy requirement per pound of weight as a cow, even assuming they were endotherms? Probably less, so let us posit a food need of the growth of one square mile of Iowa prairie per animal.

Of course, sauropods didn't eat grass. Grasses hadn't evolved yet. Perhaps their fare was richer than modern grasses. I think it may have been, because with grasses came a big change in the atmosphere: ultra-low carbon dioxide.

Prior to the evolution of grasses and other plants that use C4 photosynthesis, the amount of CO2 was never less than 1000ppm. C3 (and CAM) photosystems can't draw down CO2 below that point. But an atmosphere like that would facilitate heavier cover by shrubs and other small plants.

Today's CO2 level of 380ppm, while well above the 260ppm of the 1820s, is much less than the optimal level for the growth of leafy plants. Experiments with boosting CO2 to 580ppm have shown that most plants grow faster and more succulent; they'd be better eating!

I conclude that, while Mesozoic environments may have been more productive than modern ones, due to increased CO2, they were probably no more than twice as productive. Of course, that is comparing any area to itself under the different conditions, and with a different array of herbivore food.

So if it took a few hundred acres to feed each large sauropod, how big could their herds have been? It all depends on how far such a super-elephant can walk in a day. A dozen cattle on a square mile of Nebraska prairie need to keep on the move. After cropping the grass in one area, they can't return for a couple of weeks (let's ignore the winter situation for this exercise). So if they form a single herd, and I have observed that a herd of a dozen is quite common, they need to cover the whole square mile in two weeks, walking 6-10 miles daily (While we might model a cow's motions as a plowman's row-turn-row, they operate more randomly and thus cover even more ground).

Now if each sauropod needs a square mile or more, a herd of a dozen might need 15-20 square miles. Their long necks are a benefit here, as they reduce the walking needed to browse the trees and shrubs (remember there's no grass). It is possible that they need walk no further than a cow does, each day. It also means, however, that the herd spends most of its time spaced two neck-lengths apart, for more efficient "mowing". I consider that reasonable. Let us also remember that their mode of feeding was more like an elephant's, stripping the trees to neck-height in addition to slurping up all the shrubbery.

With all this in mind, I imagine this kind of scene, as a Mesozoic rancher on horseback. I can see a sauropod from ten miles away, so I can survey all the herds in an area of 300 square miles (1,200 sq km). That land area supports a few hundred of them, but in loose clumps here and there, perhaps in 20-30 "small" herds. They'd need to take turns going over to the river for a drink. Taking large herds of cattle to a river creates an awful, muddy mess. When left to themselves, they go at more scattered times. Dinosaurs ought to have developed/evolved similar habits.

If I am instead on foot, so I cannot see more than three miles (though I might see a sauropod's up-stretched neck from six or eight or ten miles away), I can still see as many as 30 animals, though the nearest is probably half a mile away, and for safety's sake, I hope so! The more immediate risk would be falling into a dino-sized "pie", which could weigh several times as much as me…but monster feces is better left to another riff.

Tuesday, January 26, 2010

Poor little cult girl

kw: book reviews, nonfiction, religion, cults, memoirs

Would you give your newborn daughter to this man? A couple did just that nearly thirty years ago. Though they raised their daughter, every detail of their lives was under the control of their Guru, Sri Chinmoy. She was named Jayanti Tamm, and declared to be the Chosen One from birth; she would be the pre-eminent disciple, the perfectly "God-realized" one. Her fate would be to forever sing the praises of Chinmoy, who effectively became her god.

She was his pre-eminent disciple for about fourteen years. At age fifteen, she began to wonder a few things. Though she was treated quite harshly for any infraction, she had had a neurosis of complete submission instilled into her, and could never rebel for long. As Ms Tamm recounts in her memoir Cartwheels in a Sari: A Memoir of Growing up Cult, it took her ten years to overcome the emotional bonds that held her.

She was lucky. Overcoming a deep-seated attachment that is nearly one's entire life is no small matter. In her memoir, she writes with a peculiar double vision. She observed Sri Chinmoy's inner circle her whole life, for many hours each day, even once she started school (the guru didn't like that, but was unwilling to flout truancy laws). She records her feelings, but also speaks of evident hypocrisy the guru displayed. One is her child-view of this god-figure, who claimed to be the unique manifestation of the Supreme; the other is her more mature self looking back. The two blend to indicate that, at some early age, she became aware that not all was right.

By age fifteen, she began to think for herself. She has a formidable intelligence, which could not be satisfied with mindless subservience. Yet the guru's hold on her was complete (I term him "the guru", though she consistently calls him Guru; I cannot bring myself to use that title). She existed to make him happy. When she could subdue her mind (the "poisonous mind" according to Chinmoy), she felt fleeting happiness at his every attention, even a glance. But it could not last. She swung between the guru-world and the "outer world", with wilder and wilder gyrations until she was expelled.

The breaking-away process that occupied her for ten years is covered in about half the book. She goes into shuddering, painful detail. It is all necessary. For those who have never fallen prey to a cult of personality, the power of such a person's hold is nearly inconceivable. A cult leader is, almost by definition, a psychopath. No sane person could so consistently damage and destroy others for his or her own benefit.

Chinmoy is my poster child of Peter Pan gone wrong. He never grew up. He learned very early how to manipulate others to satisfy his every whim, and he lived a life of almost total self-gratification while demanding utmost asceticism of his disciples. He used up disciples like Kleenex. Cross one of many lines, and he'd declare you an ex-disciple. But first he'd try the mix of charm and intimidation that psychopaths do so very well, to bring you into line. Then at a certain point, the phone would ring, and your former life would be over. To all "true disciples" after that, you don't exist. Yet Ms Tamm calls this an unintended mercy. Being suddenly cut off to that extent allowed her to find herself.

There was another mercy. Her father and brother shunned her as instructed, but her mother refused to abandon her, and rather than expel her from her dwelling in cult-sponsored housing, drove out the messenger who came to evict Jayanti, and instead emptied the place of all disciples. Without her mother's help Jayanti may have died. Indeed, she attempted suicide by subway train, but was rescued by a bystander. It was the guru's intention that all ex-disciples die, "punished by their Soul" (which indicates he misunderstands the soul).

Instead, now two years past, the guru has died, though dedicated disciples carry on his purported "work". Within a few years, the Sri Chinmoy phenomenon will either die away, or its leaders will organize into a Yogic denomination and carry on, one more dead body that refuses to rot.

The author is now a professor, is married with a daughter, and is, I sincerely hope, going on with life as a much more normal human.

Monday, January 25, 2010

A new standard for olive oil?

kw: observations, food, cooking

I was taken aback by seeing a new Crisco advertisement that promotes three kinds of olive oil for three purposes. The three Crisco grades are Extra Virgin, Pure, and Light. E-V is touted for salads and other "cold" uses, Pure for sauteing, and Light for highest temperature use.

Let me say at the outset that I've used only extra virgin olive oil for decades, for all purposes, with no problems. I suspect this is a marketing scheme to get us to have three bottles of product where one will do.

According to Pacific Sun, extra virgin olive oil has these characteristics:
"In scientific terms Extra Virgin olive oil is oil that has a free fatty acid percentage of less than 1%.

"In order to be Extra Virgin olive oil must be extracted only from olives, the fruit of the olive tree, and can not undergo any treatment other than washing, decanting, centrifuging and filtering. It excludes oils obtained by the use of solvent extraction or re-esterification methods, and those mixed with oils from other sources."
Their web site describes all the accepted grades of olive oil. "Pure" and "Light" are not among them, although "Lite" is, as a designation of certain mixed oils.

Will Crisco succeed in their attempt to set up a new naming standard? They may, but I hope not.

Sunday, January 24, 2010

Chronoclines

kw: evolutionary theory

A cline is a gradual variation in something. For example, the thermocline is a change of temperature in the ocean, and is used specifically to refer to a range of depth in which the temperature change occurs at a greater rate, or in a reverse direction, than in most of the ocean.

A chronocline is a change over time, a change of some measurable character. For example, the average life span in America had changed from about 35 to more than 70, in the past 200 years. Much of this change occurred in the 20th Century, because of improved public health and the development of effective antibiotics. One could call the past 100 years a cline in American life span.

In evolutionary theory, clines are an important concept. The factors that underlie evolutionary change are
  • There is variation within a species and new variations arise continually through mutation,
  • Some varieties leave more offspring than others, and
  • Most individuals die without leaving offspring.
Only for humans and for some domestic animals do a majority of the members of a species leave offspring. With the three factors listed above, we would expect that a species will be either well adapted to its environment, or that the mix of varieties will change over a few generations to improve a mismatch. For example, if the average climatic temperature falls by a few degrees (the beginning of an ice age, perhaps), we might expect that the fur of mice or lemmings will get thicker and the animals will tend to get fatter in the Fall (or the animals may die out in that area if the change is too great for them to adapt).

Looked at another way, in any population of mice, some individuals have thicker fur than others due to natural variation. In a stable environment, the "average" amount of fur is the best, and large variations tend to get weeded out. Nonetheless, there is some natural range. Now, suppose we have that drop in temperature. Previously, the mice with the thickest fur were a little more poorly adapted than the "average" mouse. Now, they find themselves with an advantage. They survive winter better, and are the ones leaving the most offspring. Within a few generations, there is a new average, and those whose fur matches the former average are now somewhat disfavored.

If temperature changes gradually over many generations of mice, we might find that, when the environment stabilizes, the range of fur thickness is completely different from what it was earlier. The cline in temperature was followed by a cline in fur (and other characteristics, no doubt). Now, were you to compare a group of mice collected "today" with a group collected before the temperature changed, you might think they are a different species. But if groups of mice were collected from every generation, a gradual change would be seen.

Now, suppose we are talking about mouse fossils, and all this happened thousands or millions of years ago. Fossils are poor samples of the biodiversity of an area. But if we get enough samples, it is sometimes possible to trace variations like that described. However, fur doesn't fossilize except very, very rarely. Bones and shells fossilize, so things that affect the shapes of bones or shells are what we have to work with.

Disclaimer, this is a made-up example, for simplicity. It is based on a real example described by one of my geology professors.

This cliff is like many limestone cliffs, with various layers that weather differently. The limestone in the middle has a more resistant layer above, and a less resistant layer below, so we get an overhang. Within the middle layer, there is also a gradual change in the amount of silt and clay from bottom to top.

If you were to collect fossils from the three spots at the ends of the arrows, you might find shells such as those shown. Ideally, you'd collect a few dozen shells at each level so you could study variation within each population. Then, that population with 19 ribs might be seen to vary between 16 and 22 ribs, though 80% of the shells collected have either 18, 19, or 20.

Side note: the next ten times you eat an orange, first count the segments. Clementines (Mandarin oranges), for example, have an average of 11 segments, but the range, in my experience, is from 8 to 13.

Now, if you stop with three collections, you might conclude that these shells represent three species of Pecten (scallop). However, what do you think you'll find if you collect at two more points, one above the middle and one below; or if you collect a dozen shells at each foot of height up this layer (perhaps twenty collections)?

If this represents a cline, you'd find that the average would vary along a trend. Then instead of three species, there would actually be one clinal species, a chronocline. Now, the question to ask is, how common is such a situation? It is actually rather rare, for two principal reasons. Firstly, it is rare to have a continuous exposure of fossil-bearing rock that encompasses a slow, gradual change in environment. Secondly, what looks like a climate-cline may really represent the sideways shift of an environmental boundary area.

For example, if one beach is mainly sandy and down the beach a mile you have mainly mud, somewhere in the middle there will be a mixed sediment. If a growing delta gradually mixes in one sediment, a vertical section in the middle will appear to be clinal, and in a sense it is. But the shells found in the sediment will probably not form a chronocline. Instead, one kind of shell is best adapted to sand, and another to mud. If mud encroaches, you'll get gradual invasion of the second kind of shell, while the first kind retreats to sandy areas. For a chronocline to form, you need a change of environment that is widespread enough that the critters don't have anywhere to go, and it must be slow enough that the population can shift. Even then, a population will tend to remain stable until a large proportion of its members are overstressed by the change. The smaller a population is, the more rapidly it can generate new varieties and the more quickly favorable new varieties can take over.

To summarize: a chronocline illustrates how one species might gradually change into another, but it is rather arbitrary where to put the boundary. Environments and fossil formation seldom "cooperate" so as to leave a clinal series of fossils. A cline is one set of evidence that evolutionary change is driven by natural selection.

Saturday, January 23, 2010

Our fractured time sense

kw: observations, time perspective, calendars

I have been researching the 2012 craze. While I know it is largely a scam, I want solid data behind what I say when the subject comes up. At the 2012Science Blog I found the statement that we, as the Maya did, use multiple calendars. I hadn't thought such a thing before, so I contacted the blogger. Our discussion led me to some interesting insights. Firstly, While we do have different calendars in use by different cultures ("Civil" in the West, which is a Catholic calendar; then Chinese, Jewish and Islamic calendars used ceremonially by their various diasporas), just within the Western Civil calendar we have several ways of counting calendar time:
  • Day names in a 7-day, or weekly, cycle (Sunday, Monday, etc. in English).
  • Day numbers from 1-7 in the weekly cycle, but seldom used.
  • Day numbers from 1-365 (or 366) in a yearly cycle. This "day count" is mainly used by merchants to calculate "shopping days until Christmas".
  • Day numbers from 1-31 (or 30, 29, 28) used within a month; an irregular cycle.
  • Week numbers from 1-52 in a yearly cycle, also rarely used but found in calendar/mail programs such as Lotus Notes.
  • Month names in a 12-month, yearly cycle.
  • Month numbers from 1-12 in a yearly cycle, mainly used for writing dates compactly.
  • Season names in the yearly cycle. These are interesting, because we have at least three ways to determine a season boundary: Astronomical, Signs, and Business. Astronomically, Spring starts with the Vernal Equinox on March 21 or 22. The signs of Spring could be sighting the first robin or daffodil, or ice break-up on a river. Spring season for business purposes starts whenever garment salespeople decide to put winter coats on sale and begin filling the racks with lighter wares and seasonal items such as umbrellas.
  • Business quarters, which are usually 91 or 92 days in length; Q1 begins when a business (or civil entity) begins its Fiscal Year; a cycle of four per year.
  • Year numbers in a linear sequence. We have agreed-upon meanings for year numbers covering all of history since the Big Bang more than 13,000,000,000 years ago, but usually confine the writing of dates to periods beginning about 400BC with the Golden Age of Greece. Note that there is no "year zero" when using BC and AD (or BCE and CE), so 400BC equals year -399 in an undesignated count.
  • Century numbers in a linear sequence. This is the twenty-first century.
  • Millennium numbers in a linear sequence. This is the third millennium since 1AD began the first millennium. This convention is seldom used.
I had not thought before that our time systems are all cyclical for periods shorter than a year, and linear for years, centuries and millennia. We don't think of centuries and millennia as cycles, though we could. The current interest in December 21 (or 23), 2012 is because it (probably) is the last day in the Mayan "long count", which is not actually the longest period the Mayans wrote about, but was the longest cycle used for official inscriptions commemorating dates such as the coronations of kings.

We do have a "long count" of sorts to care for. The Gregorian calendar uses a 400-year cycle to determine which leap years to skip to keep the vernal equinox in the right place. The Gregorian Year is 365.2425 days in length. However, there is still a small fraction of a day left out. There are two definitions of an Astronomical Year, the Mean Tropical Year of 365.24219 days and the Equinoctial Year of 365.24237 days. If we want to keep our calendar lined up with the former year, we'll have to make a correction by about 4810AD; for correcting to the latter year, we can wait until about 9300AD, depending on how much the day and year length have changed by then.

So sometime before 4800AD we have to decide which astronomical year to adhere to. Ultimately, we keep our calendar in sync with the sky, so that the precessing equinoxes happen on the same day (within a day or two) year after year. And the Mayan long count? It has similar significance to December 31, 1999 (or 12/31/2000 for those of us who start counting with "one"!): the last day of a significant era, but with no prophetic meaning.

Friday, January 22, 2010

Beautiful obsessions

kw: folk art, fine art, photographs

If you define Folk Art as art produced for one's own pleasure, by someone who is not attempting to make a living at it, then most art is folk art. Then what is Fine Art? Here are two definitions:
  • art created for purely aesthetic expression, communication, or contemplation.
  • the visual arts which include painting, drawing, printmaking, sculpture and some performance art, as distinct from art forms such as poetry, literature, dance and music.
So I guess my mobiles qualify as both folk art, and as fine art. Note that I didn't say "most fine art is folk art". While this is true, some people's continual clowning or other "day of one's life performance" is a kind of folk art of the acting variety. Is dancing at home with your partner a kind of folk art? I'd say so.

While I am frequently on the lookout for examples of unique folk art (of the fine art sort), the work of Jason deCaires Taylor, while solidly in the professional art arena, is certainly unique. This sculpture, "Man on Fire", is situated in 8m of water off Cancun, Mexico. It has been there long enough for some coral and other sessile sea life to grow. Indeed, getting coral to grow on his sculptures is the point of Taylor's work. They are made from a mixture of concrete and coral sand, to present a surface attractive to coral animals. He is presently involved in an installation to comprise 400 statues, all life casts of whole persons.

I collect fruit stickers (and veggie stickers when they show up), just pasting them at random onto notebook paper. Barry Snyder, the Stickerman, enlists friends to gather them by the thousand so he can produce portraits such as this Sgt Pepper picture. I don't know how he keeps them prior to putting the portraits together; most papers you stick them to, they are hard to remove intact.

It is nothing new to state that all people are artists of one sort or another. What is it about art? In my own case, producing a work of art focuses attention to a rare level. The sense of flow that accompanies the otherwise tedious activity is a timeless state that is quite addicting.

In that regard, planning a road trip, particularly now that mapping software is effectively free (for the modest cost of a computer!), with the bemused contemplation of alternate routes, side trips and sights to see, is a kind of art. I get the same satisfaction from a well-executed road trip that I do from completing a mobile. But the planning is the greatest pleasure. Sometimes the trip itself is anticlimactic!

But we each have our favorites. Producing sticker portraits is probably a great pleasure for Stickerman, whether or not he sells any. But many people would find themselves bored or frustrated by it. I can see myself perhaps making simple decorations with stickers, at most. I suspect, though, that Stickerman would find mobile-making a drag. Stickers are "his thing". What is your thing?

Wednesday, January 20, 2010

Handheld photomicrography and reticle

kw: photomicrography, photographs, cameras

Having only a laser printer at my disposal, I've been trying to make object-plane reticles to calibrate the magnification of photomicrographs. This first, poor item is 5x5mm, with the light and dark bars intended to be ¼mm (250µ) wide. However, uniformity is awful:

Next I tried a small square containing other squares. My initial attempts were aimed at having the smaller squares be 0.1mm (100µ), but after various tests, I settled on the square being 2.5x2.5mm, with the small squares being 250x250µ. If you click on this image, the larger image you'll see has a magnification of about 52X. This one is closer to 15X. The target insect is a midge about 1.2mm long in body, with legs approaching 2mm long:

This last image is a 1x1mm clip from a more highly magnified original, centered on the midge's head. At this magnification, 1mm = 480 pixels, so if you click on the image below, the larger version, being 480 pixels across, will occupy 4.8 inches on your screen, or a magnification of 122X:
With this microscope, at least, handheld photomicrography works pretty well. I am considering a jig that will screw into the tripod mount and attach to the microscope tube, so I can get more repeatably aimed results, and even make short videos (like of the critters in my birdbath). But for most purposes which I use this microscope, this method is sufficient.

Watch water

kw: observations, water, shortages

This chunk of the Texas panhandle (near the so-named town) is green for one reason: the Ogallala Aquifer. The left quarter of the image is December imaging, the rest is June. Irrigation using Ogallala groundwater is what keeps the area from being a howling desert.

This huge underground mass of water-laden sedimentary rock has supported the agricultural miracle of the West for most of a century. It is mined water, though, and it is running out. Water is being removed throughout the eight states in which the aquifer occurs, but is replenished only by rainfall on small exposures in South Dakota's Badlands, a semi-arid area (less than 16 inches yearly moisture).

The aquifer is one reason the nation seems to have enough water to go around. When it runs out, in the lifetime of today's high school and college youngsters, the U.S. will follow Yemen and other countries in rationing water.

The U.S. is lucky. Few aquifers around the world are so large, and a couple of those that do are in areas with plenty of rainfall already. Nearly all the world's people have to rely on rainfall and its derived waters in rivers and lakes for all their water needs. As world population grows, more and more areas will suffer water shortages. Take a look at this map, showing where shortages occurred into the late 1990s (click for a larger version):

This is one of four maps to be found in this BBC article. The map that follows is the third one, showing expected water stress in the 2050s. By then my son will be in his 70s, but what of his children? We are about fifteen years into World War III already, and it is primarily motivated by cultural and religious extremism. WWIV, or a morphed WWIII, will be fought over water. You can see in the 2050s map that China and India, where one-third of humanity resides, will be in serious trouble long before 2050. And by then Africa could be home to another one-sixth, making half of the human race desperate for water.

Will climate change help, or harm the situation? A major interpretation of a warmer climate is that global total rainfall will increase. However, some areas could experience less instead of more. It is certain that wars will be fought over access to water; their location is also pretty easy to predict in general terms: between Russia and the water-poor areas south of Siberia, and between the equatorial African countries and their neighbors to both the north and south.

I expect the Water Wars to begin in my lifetime; nobody will wait for 2050. Plan accordingly.

Silver skin

kw: medicine, skin conditions

A little item in Ripley's Believe it or Not: Seeing is Believing impelled me to learn more about Argyria, a condition in which ingestion of silver salts or colloidal silver leads to silvery skin. According to an article at BryanLGH College of Health Sciences, the condition is permanent.

That makes me wonder. The Ripley's item was about a Vermont woman who has had silvery skin for fifty years. Our skin is replaced completely every month, so the silver must migrate downwards as old skin is sloughed off, or it would soon be eliminated, wouldn't you think? Aha, but that is just the epidermis. The dermis is another story, and it must be there that the silver lodges.

Tuesday, January 19, 2010

These roots are a little deeper than we thought

kw: book reviews, nonfiction, science, history

In 1879 Edison and his helpers produced a carbon-filament light bulb that stayed lit for many hours without burning out. This wasn't the invention of the light bulb; people had been making them for fifty years. But this was the first practical one, with a stronger filament and a better vacuum, plus a few other innovations, that formed the basis for a lighting system which was Edison's real invention.

When Philo Farnsworth got an all-electronic television system working, he was 20; it was 1926. He'd been working on it since he was fifteen and was inspired by the parallel furrows in a field he was plowing. Earlier that same year, John Baird had demonstrated a mechanical system for dissecting and reassembling an image, which he had been working at for more than ten years. Which one invented television?

Rick Beyer's fourth "Never Told" book, The Greatest Science Stories Never Told: 100 Tales of Invention and Discovery to Astonish, Bewilder, & Stupefy, surveys the light bulb story well, but mentions only Farnsworth in connection with TV. These stories are somewhat variable in the "never told" category: many folks know the Archimedes-in-the-bath story, or that Hans Lippershey invented the telescope that Galileo used to revolutionize astronomy. Hardly anyone knows of the powered wagons one might call automobiles that were built in Paris in 1769 and Philadelphia in 1805 (It took another 100 years for the idea to catch on).

The stories in this book introduce us to the men and women who pioneered ideas ranging from the digital computer (1822, Babbage and Lady Lovelace) to the Zipper (1893, W. Judson), from the walkie-talkie (1938, Al Gross AKA Veeblefetzer) to the computer mouse (1968, D. Englebart). And who really invented the Internet? Lotsa people, but central to the action was Len Kleinrock, who installed the first server in 1969 and had it talking to a colleague in Stanford by October that year. At that time computers were still too large to see over (not really; the office-desk-sized IBM 1130 was introduced in 1965—this from my own knowledge, not the book).

The book is a fast read; each essay is about a half page, accompanied by a few pertinent pictures, some with extended captions. It is also a fun read. At first, I was pitting my wits against it ("I knew that…and I knew that…Ooh, surprise!) but soon I simply reveled in the delight of learning about many little-known inventors and innovators.

One of my favorite Peanuts cartoons has Lucy telling Linus a number of truly off-the-wall "explanations" of nature, when another girl asks what she's doing. "Explaining the little-known facts of nature," she says. When the girl asks her, "Then how do you know them?", Lucy replies, sotto voce, "I make 'em up." The book's bibliography makes it clear that Rick Beyer didn't have to make anything up!

Monday, January 18, 2010

Higher literary hijinks

kw: book reviews, nonfiction, literature, practical jokes

A well done hoax is the highest form of practical joke…except when the hoaxer is serious, or seriously disturbed. Literary Hoaxes: An Eye-Opening History of Famous Frauds by Melissa Katsoulis presents a collection of such paradoxical concoctions, some good, some bad, and a few downright ugly (the hoaxes, not her writing).

Some people have called Dan Brown's Da Vinci Code a hoax, but if so, it is a meta-hoax: the mythology of the Priory of Sion upon which it is based is itself a hoax that will not die, initially perpetrated in the 1940s, though claiming (of course) many centuries more history than that. To add to the confusion, there is a somewhat older entity named the Priory of Zion, but with greatly different aims than the "Sion" version.

Most hoaxes come in three categories. The largest number, called by the author's sources "genuine hoaxes", include the Hitler Diaries and the Donation of Constantine, which were intended never to be discovered as hoaxes. Such hoaxes have the aim of making money or political gain. "Entrapment hoaxes" are designed to expose pretentious litterateurs to mockery for being taken in by works in a popular tone which are purposely done badly. One of the most famous seems to be ongoing; a falsified letter was accepted by a pompous biographer as genuine, and was published in full in the biography, where it anagrammatically, and scatologically, ridiculed the biographer. Finally, "mock hoaxes" are literary works intended to obscure the true author's identity. An author may feel the need to experiment without being pilloried for straying from "what has worked". Writing under a pseudonym is one thing, and is not really hoaxing; making up a biography and past oeuvre for one's imaginary self is more obsessive, and sometimes effective.

Some hoaxes are hurtful, such as those written by phony Holocaust survivors, which invariably damage the reputations of genuine survivors' work, or those written across racial boundaries by authors who really don't know what they are talking about. Several of the latter sort have been written in Australia, by "Aborigine wannabes", causing justifiable umbrage among genuine Aborigines. America's First Nations representatives are also rattled on occasion by pseud0-Indians writing of things they barely comprehend.

The book consists of essays, with a tone that varies from admiration to disapproval and even contempt. In a number of cases, the question that looms largest is, what did the hoax's author believe? Some claimed they had no intent to deceive, but rather to work through their own phobias or neuroses by using a metaphorical setting (such as the Holocaust). Oppositely, what are we to make of Mark Twain, who seldom wrote without exaggerating, conflating or inventing? Just as a painter often lightens a shadow or dims a highlight so as to show detail that a photo might miss, a writer may focus on what more "accurate" reporting might pass over.

In the end, intent means a lot. It is hard to call some of these things hoaxes because they were real to the perpetrator! What I find ironic is that some hoaxed productions, written out of frustration at "legitimate" work being rejected, have much higher literary quality than that rejected work. Sometimes you really have to get out of yourself to do good work.

I think of my favorite musical clown, Peter Schickele, whose PDQ Bach spoofs portray poor, imaginary PDQ as a hoaxer "whose work was so bad he put others' name on it so it might sell". Schickele's spoofs are brilliant. But I have heard a concert of music he wrote in his own name, and I must consider it a "pity production": the music was awful. Then there is a poet I know (a relative) who is quite good, but it is a piece he wrote while playfully trying out a very different style that brought his English teacher to tears.

Here is what is ultimately sad about hoaxes: they aren't necessary. Work done for joy is simply going to be better than that done from selfish anger. A frustrated author just might need to use a pen name and write in as different a voice as possible to kick free of the doldrums. That's usually healthy, and leads to much admirable work. It is sad when someone goes farther and burns more energy creating and maintaining a facade, than doing the work itself.

Saturday, January 16, 2010

A lonely Thanksgiving

kw: family history, artifacts

My father never dreamed he'd spend Thanksgiving 1945 still in New Guinea. The war had ended in August, he'd mustered out many of his men, but the Army for a series of reasons he didn't understand kept many men and most of the officers in place. So in his letter home for November 22, 1945 he included this menu for the day.

Of the hundreds of letter he wrote to his intended (my mother), this is one of the most poignant. In a paragraph about the middle he wrote,
"I've decided to resign to my fate again and plug along till my number comes to go home. All day and way into the nite each day all you hear is griping about points, when I'll go home, etc. Many guys almost drive themselves nuts, worrying about it. There must be thousands, but in the last month I haven't talked to anyone who has been overseas longer than me."
Dad had one brief visit home in mid-1943; thereafter he didn't return until late February 1946. He and my mother married in early March 1946.

I've just finished initial curating of my parents' wartime letters for WWII. It has taken months. I have yet to read more than little bits here and there as I put each sheet, or pair of sheets whenever only one side was used, into clear jackets. Our next generation is just getting into their college years (my brothers and I all had children quite late), so it may be left to a younger family historian to read all the letters and then, who knows what?

Here is a closeup of the Thanksgiving Dinner Dad and the rest enjoyed that warm day in the tropics. Quite a spread. I dunno; seems to me that turkey noodle soup isn't quite the same as roast turkey, but when it is a warm, rainy day, the spirit of the season isn't quite the same anyway. Soup is easier to transport half across the planet than frozen turkeys, anyway.

This bottom section of the page has the ration for the two holidays, per 100 men. Multiply this by twenty or so, for the men who were still deployed that Thanksgiving weekend, and you can see why military cooks need large staffs! The biggest single item, 170 pounds of potatoes per 100 (probably 1.5+ tons for the whole bunch)…that is a lot of peeling.

Back to Dad: he didn't write every day, but I still have ten binders full of his letters. Most of Mom's letters were lost, I only have the first year, but that is four binders because she did write every day, for four years. Is it any surprise they were married 58 years? I've been lucky; my own courtship lasted less than a year, yet in a few months we'll have had 35 years of marriage. We both come of long-lived stock, so we could last another thirty years or more. That suits me.

Thursday, January 14, 2010

De-ephemeralizing a light show

kw: art, artists, photographs

One nice thing about a book like Ripley's Believe it or Not: Seeing is Believing is that it clues a fellow in to interesting and unusual things. Today I came across their report on sophisticated images made with moving lights, produced by Lichtfaktor, a group of German artists.

They produce images such as this by making a very long exposure while one or several artists, using flashlights, lightbars or other light-emitting equipment, and wearing black or dark clothing, moves through the frame while moving the light sources in some pattern they've pre-designed. It is a kind of performance art captured in a single image.

No matter how they plan, the element of improvisation is huge. When you have both foreground and background lighting going on, as this image has, you also have to be careful that the people in front don't make a "blip" by running in front of the lights behind. Timing and staging make or break such a shot. This is way cooler than a pic of someone writing their name with a sparkler.

Wednesday, January 13, 2010

A day must start somewhere

kw: book reviews, nonfiction, essays, sunrise

"Rosy-Fingered Dawn" is a metaphor that goes back at least to Homer, and probably to the beginnings of language. This image, from artist and calendar maker Philip Johnson, best exemplifies the feeling. Dawn Light: Dancing With Cranes and Other Ways to Start the Day by Diane Ackerman puts such feelings into words.

While I read the book in sequence, and it is arranged in seasonal order beginning with Spring, one can read these essays in any order; each can stand alone. The author thinks about a great many things, and here uses the days' beginnings as a framework to muse about them all.

The crane business? An early chapter titled "A Calamity of Cranes" describes the efforts of Operation Migration folk and others who raise whooping cranes while wearing shapeless burnoose-like garments, so the young will not imprint on the human form. They imprint them on hand puppets and an ultralight aircraft instead, so they can be taught to socialize as cranes and to migrate to the cranes' historic wintering grounds.

Later we learn that an inspiring force for her was Claude Monet, who pictured the same scene over and over, usually by dawning or early light, and that both Monet and Ackerman are inspired by the Japanese artist Hokusai, most famous for Thirty-Six Views of Mount Fuji and The Great Wave Off Kanagawa. Viewing things from many angles, we learn more than any one view can encompass.

The author likes to imagine what being a different sort of creature is like. In her essay "Water, Water Everywhere" she imagines what being water, just water, might be like. After imaginings (scattered here and there; not in any one section) of songbird, owl, rabbit and pine tree, "being water" is perhaps the biggest stretch. Just as the earth is, by volume, mostly oxygen, so we are, also by volume, more than half water, yet it is the non-water that produces structure for the structureless. Only under conditions of low temperature and/or high pressure does water have its own structure, and then it is too rigid for motion.

As I read, I found myself remembering an old saying about Chinese food: "An hour later you're hungry again." While for Chinese food, it may be said that a meal built around white rice doesn't stick with you, for Ms Ackerman's writing, it is simply the desire to dip in, again and again, to the stream of her prose. The book is too short.

Tuesday, January 12, 2010

Blue sky from above

kw: photographs, meteorology

This image is a small clip from a large satellite image found at www.raize.ch, titled "High resolution satellite images of the Yecheng-Western Tibet-Kathmandu-Highway 219".

What piques my interest here is the deep blue tint of the shadows that run diagonally from top left. We are seeing blue sky from above! This is not seen in most satellite images for two reasons: firstly, the vertical relief in most images is small so any bluing of the image is automatically corrected for in the camera, and secondly, there are seldom these deep shadows that allow the blue reflected from the sky above to dominate.

This reminded me of a question I've seen a time or two: "Is the sky blue for planets around stars of different colors?" The answer is, it depends. The sky of Mars, for example, is pink because there is always suspended reddish dust, and the air column is 1/1000th that of Earth. Any blue light scattered by Mars's air is correspondingly fainter and the dust color dominates. But if there were no dust, the sky would be blue, though a very blackish blue.

Now, how about an Earth type planet orbiting a "blue" or "red" star? Clear air takes the light that passes through it and scatters a small proportion of it via Rayleigh Scattering, for which the amount scattered varies as the fourth power of photon energy. Thus, blue with wavelength 450nm is scattered 4.4 times as much as red light with wavelength 650nm. So no matter what the spectrum is of the light passing through a clear gas, the light scattered at right angles will be much bluer. Of course, for a blue star, the light is already blue, and just gets more intensely blue. For a "red" star, we need to realize that even a very cool M9 star is hotter than a carbon arc, which itself is quite a bit hotter than the "whitest" tungsten filament lamp.

There is a contrast effect at work here. The Sun is considered the standard of whiteness by astronomers. The sun's surface temperature is close to 6,500K. Its actual color is rather bluish, compared to the color we see after its light has passed through the atmosphere. Even on the clearest day, at elevations near sea level more than one-third of the light has been scattered, removing lots of blue, so that it has a spectrum more like something at a temperature below 4,000K. There are complications, because stellar gases don't have "flat" emissivity, but I don't want to go into the slight difference between color temperature and actual temperature here.

Any star cooler than the Sun will look yellow or orange by comparison. But the "white" light from a filament lamp (the next generation is likely to forget what they are!) is actually quite reddish, for the filament's temperature is about 2,700K. An M9 star's surface temperature is close to 3,300K, a couple hundred degrees hotter than a carbon arc (used in old-fashioned movie projectors and in searchlights).

If you focus a lot of the "white" light from a tungsten lamp into a beam passing through clean air, and look at the scattered light with a sensitive camera, it will be quite blue. Thus the sky for an Earth type planet around any star will appear blue. If any planet has a green or purple sky, it is because something in the air is changing the spectrum; there's no getting green or purple from a thermal spectrum just by Rayleigh scattering.

Monday, January 11, 2010

Gleaning the edges of normality

kw: book reviews, nonfiction, phenomenology

Four-eared cats, two-headed snakes and three-legged men are but one genre of fascinating things found in Ripley's Believe It or Not: Seeing is Believing by the editors at Ripley Publishing. This isn't a book one usually reads from cover to cover (though that is what I intend to do). It is a warehouse of interesting things to be plumbed, to be wandered through.

Ripley was a realist. Fortean speculation was not for him; Charles Fort sought paranormal explanations for unusual phenomena, while Ripley sought the unlikely and rare, but explainable, that dwell at the limits of normalcy. The 4-eared cat Yoda is considered to have a genetic mutation that happens to be visible, but neither harmful nor helpful; the extra ears are just there.

In a world of 6.5 billion people and trillions of animals and plants, a few are bound to be "one in a billion" in some way or other that we find fascinating. Just at random, without glandular disorders, a couple of quite ordinary size (1.75m or 5'-9" for a man and 1.6m or 5'-3" for a woman) might produce a child who grows to seven feet (2.1m), or who never exceeds four feet (1.2m). This is rare enough to be a marvel. It takes glandular problems to produce humans taller than eight feet or shorter than three, and it is these that are chronicled in Guinness and other record books.

Of quite another order of interest, we find the unusual feats, not of daring or danger, but of art and quixotic caring, such as the women who decided to knit a tree a sweater in Yellow Springs, OH. You can't slip a sweater over the branches, so the sweater has to be knitted in place, as we see here.

This tree-hugging garment reminds me, on its intimate scale, of Christo's landscape-wrapping artworks (one of my brothers participated in erecting one of them). I like it better than I like putting sweaters on one's pets. It is a warmly human thing to do, which probably does neither good nor harm to the tree, but rather creates a community, at least temporarily, of those women (have any knitting men added their bits?) who choose to add their knits and purls to a growing project. It is a social act.

I have by no means read all of the Ripley book yet, nor even any major part of it. It is fodder for my "between-times" reading, so I'll likely return to it in future posts, as it piques my interest.

Saturday, January 09, 2010

Unhiding a hidden land

kw: book reviews, nonfiction, natural history, botany, nations

One of the first songs my voice teacher in my teenage years had me prepare for a recital was "The Road to Mandalay", based on an 1892 poem by Rudyard Kipling. I did not know at the time that Mandalay was a former capital city of Burma, now named Myanmar. I didn't even bother to wonder what kind of road would have flying fishes playing! Only this week did I learn that the "road" was the Irawaddy River, which is navigable nearly from its headwaters in the Himalayas to its huge delta in the Bay of Bengal. It is the main "road" from Yangon (formerly Rangoon) to Mandalay and points north.

I learned about this "road" while reading The Weeping Goldsmith: Discoveries in the Secret Land of Myanmar by W. John Kress, a botanist with the Smithsonian Institution. The first chapter is about the Weeping Goldsmith, or padeign gno in Burmese, which is a folk name for Globba magnifica, a ginger plant highly prized for its flowers. Legend has it that no goldsmith has been able to produce a golden replica of this flower, and one who tries will end up weeping.

Dr. Kress is an expert in gingers. To those of us who know only Zingiber officinale as the spice Ginger, it may come as a surprise that the family Zingiberacea comprises 1,300+ species so far known. Many have uses as medicines or spices. The spices Turmeric and Cardamom are from this family, all of which the author calls gingers. On his expeditions to Myanmar from 1993 until 2002, he and his colleagues discovered dozens of new ginger species and a many more other new species of plant.

In addition to the ordinary apparatus of a scholarly book, an appendix illustrates 25 interesting (non-ginger) plants known chiefly from Myanmar, and 25 species of gingers and ginger relatives. Though I call this book scholarly, it is very readable, in the tradition of classic works such as Half Mile Down or Voyage of the Beagle. It is not a highly technical monograph, but a travelogue through the seasons of the year in Myanmar, gleaned from many visits, but focusing on the monsoon, because gingers sprout and flower during the rainy season. They're rather hard to find in the dry season.

Dr. Kress's colleague U Thet Htun, shown here with his family, was a great help to the author with the logistics and contacts needed to make several of his collecting trips. The honorific U formally means "uncle", but is used like we use "Mr.", though more frequently. The feminine honorific "Daw" corresponds to our "Ms". These prefixes are used throughout the book because Burmese names do not convey any sense of gender the way most Western names do.

U Thet Htun's wife and child are wearing a concoction of thanakha, made from the bark of the citrus Hesperethusa crenulata. It is much used as a sunscreen, and its attractive pale yellow color makes it a popular cosmetic also. It is painted on the face in intricate designs, much the way henna is used in Europe.

Myanmar may be the most intensely Buddhist country in the world. This vista of the plains near Bagan shows a few hundred of the thousands of pagodas to be found just in this area, and there must be many tens of thousands of pagodas throughout this small country (its area is similar to that of Texas).

A side story comes to mind. When we lived in South Dakota, we found that it was not too hard to drive to areas in which our presence and that of the road were the only signs of human life, right to the horizon in all directions. While driving to Oklahoma in 1986, by mid-Nebraska I realized that I could always see at least three or four grain silos, showing the locations of the towns and small cities. Skip eight years. On a business trip I visited Germany, near Aachen. I noticed while driving to Aachen from Düsseldorf, in very flat country, that it "felt" like Oklahoma. I looked around with new eyes, seeing towers in all directions, seven or eight of them: they were cathedral spires! That was the impression of western Germany that sticks with me: a land littered with cathedrals the way midwestern America is littered with grain silos…or church steeples.

I don't think the density of church steeples in America rivals this display of Buddhist pagodas, however. Buddhists don't "go to church" the way Christians do. They strive to live a life of merit, so as to earn a better station in their next incarnation. No Buddhist wants to live as a jerk and return as a mosquito. This has been fortuitous for forestry. The lands surrounding pagodas are considered sacred, and all the people take at least nominal care of them. But times are changing, as the Epilogue notes, and Myanmar's teak forests are being logged and trucked to China.

During his visits, Dr. Kress was able not only to collect and record specimens, but also to train numbers of young botanists and foresters. A few visiting scholars can do only so much. It is the people of Myanmar who must preserve its forests…or not.

One sign of the growing commerce with China is signs such as this, in Western letters, Chinese, and Burmese (this is the name of a town). Though the Burmese language is tonal and monosyllabic, like Chinese, it is written with a phonetic script, one that I find pleasingly loopy. They use consonants in combinations we find difficult to imagine pronouncing (such as in the name Htun), and have 33 consonants, including one that cannot be described in English! Then there are the 16 vowel sounds. At least a couple of these require an English tongue to do things that make it ache until one gets into practice.

Nonetheless, the author learned the language well enough to carry on basic conversation, and to follow the gist of others' conversations. He has hopes to return to a country and culture so different from his own.

Thursday, January 07, 2010

A personal relic

kw: artifacts, family history

I was ten when I learned that there are more than one kind of Magic Square. This one I constructed in 1958 has a reduced magic number of 16. The magic number for an order-4 square is normally 34. The standard magic number Ms is found from order N thus:

Ms = ½N(N² + 1)

This produces the series 1, 5, 15, 34, 65… A magic square with M <>s has a reduced magic number, and one with M > Ms has an augmented magic number. Only if M ≥ Ms can all the cells contain a unique number, and then only where N > 2. The only other requirement is that M ≥ N, though where M = N the result is trivial.

Of course I didn't know all that fifty years ago. I just knew that magic squares added up to a constant, both rows, columns and diagonals. When I showed this to a teacher, she was kind enough to thank me and ask if I knew how to make one with every number different. At age ten, I couldn't, but I found an answer in the encyclopedia.

Wednesday, January 06, 2010

A genius like no other

kw: book reviews, nonfiction, biographies, mathematicians

Here it is, the Dirac Equation for the electron, in the form it appears on his tombstone. The number of people who actually understand this equation is about equal to the number of symbols it contains, and may be fewer. The only thing I understand about it is that it is laid the foundation for the "Standard Model" of particle physics.

I've just finished reading the definitive biography The Strangest Man: The Hidden Life of Paul Dirac, Mystic of the Atom by Graham Farmelo. It is a largeish book, 438 pages plus 54 pages of endnotes and a great many bibliographic entries. The subject is worthy of the attention. As the author states in his final chapter, "Great thinkers are always posthumously productive." The Standard Model, string theory and antimatter are three of Dirac's legacies that continue as fruitful realms of endeavor, keeping a large number of scientists employed, many of them running the most expensive machines in the world.

The author points out several times that Dirac was always guided, rightly or wrongly, by mathematical beauty. A theory had to be beautiful for him to deem it worthy of being, possibly, true. This led to his disdain for renormalization, the technique that allows physicists to do electrodynamic calculations without being stumped by the theoretically infinite self-energy of the electron and other fermions. He thought it Ugly with a capital U. This quest for beauty led to the work that gained him a Nobel Prize at a nearly unheard-of young age: he received the Prize at age 31, for work he'd done just five years previously (the only Nobelist I've met, Charles Pedersen, was 83 when he received his Prize, for work done a few years prior to his 1969 retirement).

A characteristic of Paul Dirac's nature was a very direct way of speaking. While this led to nearly uniform abruptness of personal discourse—and lots of seeming rudeness—he became a highly sought-after public speaker, for he could make the concepts of mathematical physics and quantum mechanics clear to nearly any audience, giving them a feeling they got the gist of it, even though the math was far beyond their grasp. This is a rare gift. In the penultimate chapter, the author speculates that Dirac was "high functioning autistic", perhaps with Asperger's Syndrome. I know a couple of such people, and it is possible but by no means certain.

It is also possible that he, an exquisitely sensitive person, was stomped into deep hiding within a defensive shell by an absolute boor of a father. I know something of a life lived in secret, of building a shell to protect myself, being the only bright kid in a series of schools full of dolts. Fortunately, I had parents who were much warmer and involved than what is reported for Dirac. Then again, I am no genius.

Dirac was lucky to find a soul mate in Eugene Wigner's sister Manci. Paul and Manci were so different from one another that they could never compete, yet they were equally sensitive, and she became the unique one to draw him out of his shell…at times.

Dirac lived 4/5 of the Twentieth Century, from 1902 to 1984, from the ragged end of the horse-and-buggy era to ten years after we quit going to the moon, but were using town-sized machines to probe particles that endure only long enough to move a tenth of the diameter of a proton. In the quarter century since his death, how much farther have we gone? There is some chance that the latest big machine, the LHC, will begin to twang the "strings" that may underlie the structure of everything. Such a string is a million times smaller than the proton. My mind boggles.

Of course, my mind hit its boggle point about forty years ago when I hit my mathematical limit as a Junior Physics major, and switched to Geology. I have read Dick Feyman's Lectures, but I can't get very far with Dirac's The Principles of Quantum Mechanics. We mere mortals are glad for the demigods who can make math work because of its beauty.

Tuesday, January 05, 2010

Gigapixel cautions

kw: photographs, photography, musings

Gigapixel photography has caught my interest, but not to the point of buying any equipment. However, I have been enjoying the stunning results that can be found on the web. At the moment (and this may change), when you visit gigapan.org, you see one of several huge images and have the chance to zoom and pan through it.

One is a very wide-angle view of President Obama's inauguration, from which these three clips were taken. This first is without any panning, just a crop from an image that nearly filled my screen (and I have a big one). With only a little zooming, you can pan around and see everything that the unaided eye would see.

Before taking these clips, I zoomed on the orchestra below the President's podium and found I could not read the music, but I could tell there is something on the pages.

This shows what you would see if you had been there, assuming normal vision. It is about a 6x zoom compared to the prior image.

Gigapixel images are produced by several kinds of equipment, but they all boil down to a special robotic mount (such as the Gigapan Epic) on a tripod that moves the camera in a pattern, taking an exposure at every step. A typical set is 150 images.

Companion software stitches all the images together into one big one. Rather than use edge matching as conventional stitching programs do, this software uses knowledge of the pattern followed by the robotic mount.

It can take ten minutes or more for the whole set of images to be taken. Things can move, which is why conventional stitching software can't be used. I have seen some amusing things, like a picture in which a person turned around between "passes", and it looks like his torso is on his legs backwards.

This image, zoomed as far as the resolution allows, shows what you'd have needed binoculars to see. It is about a 20x zoom compared to the first image of these three. For comparison with an image near the end of this post, note the smoothness of the tones.

When I first began following this subject, there was a website for "the Gigapixl Project" at www.gigapixl.org. They are apparently defunct. This is too bad, because they were the source of a few dozen images being presented by Google Earth. I tried contacting them, and the web site is gone; I wanted to tell them some of the things I outline below.

For now, a good resource for gigapixel expertise is the Microsoft Research HD View site. There are a number of high-quality gigapixel images one may view. The HD View software could well become the standard for viewing huge images.

To see the ultra-resolution images Google has made available, make sure you have the latest version of Google Earth, then open its Gallery section (lower left panel) and click as shown here.

There are getting to be so many layers in Google Earth that I have trouble remembering where everything is. Fortunately this panel is easy to use.

Note that the "e" is missing; these photos are specifically from the Gigapixl Project, when it existed. I hope Google is now securing such images from other sources.

With "Gigapixl Photos" checked, you'll see a camera icon wherever a giant image (or a few) occurs, whenever your "Eye Altitude" is less than 3,000 miles/5,000 km. Here, I have hovered the cursor atop one and the title "Devil's Tower" appears. Clicking on it opens a dialog showing a small image and an invitation to "fly" into it.

I particularly like what happens next. The gigapixel image is overlaid with the landscape, appropriately tilted so that you seem to be looking "through" it.

This crop was cut from the "window" before doing any zooming. I am going to pay attention to the shrubbery just visible on the lower right flank of the tower.

In the upper right corner are zoom and pan controls. I double-click to zoom in, use the mouse wheel to zoom out, and click-drag to pan…usually. Double-click on any area of the image to center that spot and zoom by a factor of 2-3.

Zooming in by double-clicking is more stable than using the mouse wheel; one step on the wheel turns into a whole lot of zoom. I suppose I can change that, but I haven't yet investigated it. So I double-click.

Two such steps yields about a 8x zoom, and the view as shown in the second photo of this series. I am going to focus on the small tree right at the center of this image.

Before we go on, though, note the clarity and smoothness of the image at this point. A well-taken gigapixel image will look equally good until it runs out of resolution.

And here, with another pair of double-clicks—another 6x of zoom (total about 50x)—we are clearly beyond the resolution available. 20-25x is the normal limit of resolution for a 1-1.5 Gpx image. At 50x zoom the "graininess" of the image becomes very evident. Even at 25x, where the image looks good and sharp, the sky and rocks have a grainy appearance.

This is the cause: Shooting at an ISO setting that is too high. Recall how smooth the tones are in the picture of President Obama in the third image above. Digital photography has the potential for making images that are smoother than anything film could produce, but one must use the lowest ISO setting of the camera to achieve the best "look". For most point-and-shoot cameras, that's ISO 50 or 60, and for DSLR's it is ISO 100 or 200.

This image must have been made with ISO 400. It just didn't capture enough light in each pixel to reduce statistical noise to an invisible level. Remember, point-and-shoot cameras have a sensor with pixels only about 1.5 microns square. You have to capture 10,000 photons per pixel to have a noise figure less than 3%. The noise figure above is about 10%.

I have viewed nearly all the gigapixel images Google Earth has on display, and they all have this problem. So to anyone contemplating going for ultra-size imaging: use the lowest ISO. It takes the robotic mounting a couple seconds to move the camera to each step. Whether the shutter speed is 1/100 sec or 1/4 sec will have little impact on the time it takes to gather the images, but it will have a great impact on the quality of the finished image.

Now for a side note. While looking for the Gigapixl Project, I came across the Gigapixel Project (note the "e") at Virginia Tech's Center for Human Computer Interaction. This shows a 50-panel touch screen they have recently built. They are on the way to a Gpx display; this one is probably about 120 Mpx total.

The sharpest displays are 100 dpi; a billion of those comprise 100,000 in², or 64.5 m². That would be a wall 5.7m high and 11.4m long, or something similar. Don't hold your breath for an economical home system…