हद ००३३९९ लुईस

Trying to keep up with the blogs at ScienceBlogs is like trying to dig a hole in water, they have so many. But still I was surprised that I didn’t know about Science Woman. They just posted a very cool link of their blogroll which contains a zillion links to science/tech/engineering/math (STEM) blogs written by women.http://louis-j-sheehan.com

It’s pretty good, but I noticed they are missing a few, so I sent them a comment about it (awaiting moderation as I write this). Here are the ones I read (or listen to):

• Pamela Gay’s Star Stryder and AstronomyCast
• Amanda Bauer’s AstroPixie
• Damaris B Sarria’s How I Am Becoming An Astronaut (actually I forgot to add Ms. Sarria’s blog, but it’s here now!)
• Carolyn Porco’s CICLOPS site (not strictly a blog, but c’mon).
• My old friend Carolyn Collins Peterson’s The Spacewriter
• Skepchick
• Teen Skepchick
• There’s also the new vodcast from Australia, The Skeptic Zone, which features Karen Stollznow, Kylie Sturgess, Amanda Rose, and Rachael Dunlap.

I bet I’ve missed some. If you know of more, send them to Science Woman! And let me know, too, because I have sooo much spare time to read more stuff added to my feed reader.

Tip o’ the lab coat to ScienceGeekGirl.

September 25th, 2008 2:09 PM by Phil Plait in Astronomy, Cool stuff, Science | 1 Comment »

Trans-cosmic flow broadens our horizon

In one of the weirder astronomy press releases I’ve seen in a while, it appears that material literally outside the visible Universe is tugging on material that we can see.

Hubble image of the Bullet Cluster, which appears to be getting yanked by material from The Other Side. Click to embiggen.

What does this mean? First off, let’s take a sec and talk about the visible Universe. If you go outside and look around, you don’t see the whole Earth. You only see a small fraction of its surface, because the Earth is a curved ball. The solid planet itself blocks your view. The farthest you can see is out to the horizon, where the curving Earth dips everything else below your view (well, except for tall objects like buildings and ships at sea, but we can ignore them for this analogy).

The Universe is the same way. The fabric of space is expanding, with the cosmos getting bigger every day. This has an odd effect: objects farther away appear to be moving more rapidly away from us. Eventually, an object can be so far away that the space between us is effectively expanding faster than the speed of light! This does’t violate any physical laws, because nothing material is actually moving at transluminal speeds; it’s just that there is more space itself between us and that object all the time.

This effect naturally provides us with a cosmic horizon. Any object "moving away" from us faster than light can’t be seen by us; the photons it emits can’t keep up with the expansion of space. They lose energy and fall away from view (like a slow walker on a fast treadmill… or better yet, an ant walking along a rubber band that is being stretched). So, to us, an object far enough away is invisible, beyond the Universal horizon.

Weird, huh? Yeah, as usual, things get even weirder.

Now imagine a third object, say a cluster of galaxies, that lies between us and the one that is beyond our horizon. To the cluster, the object may still be visible, because it’s closer, and therefore not receding as rapidly. It’s like an island just over the horizon to you as you look seaward from the beach; to you the island is invisible, but to someone a few kilometers out to sea in a yacht the island is still visible.

That cluster can still be affected by the more distant object, pulled by its gravity, for example. To us, farther away, we don’t see that distant object, but to the cluster it’s sitting right there and still, literally, a force with which to be reckoned.

If you want to go away for a moment and take some Tylenol, I understand. I feel a bit headachy myself just writing this.

The thing is, astronomers now think they’ve detected this force! Clusters of galaxies are filled with extremely hot gas, or plasma, heated by things like the galaxies’ motion in the cluster. As light from objects farther away passes through this gas, it gets affected by it, and we can measure that change. This is called the Sunyaev-Zel’dovich effect, and it’s too weak to measure well in individual clusters, but by looking at literally hundreds of clusters, the effect adds up and can be seen. [Edited to add: the photons that are being affected are not from the matter beyond the horizon, but from the cosmic microwave background, the relic radiation from a very early time in the Universe, but still in our visible Universe. Sorry I wasn’t clear about that in the original post.]

The total force is fairly big, in fact. Clusters seen in the direction of the constellations Centaurus and Vela appear to have an additional 3 million kilometers per hour added to their usual velocity! That means that some very large clump of matter — probably a cluster of galaxy clusters, called a supercluster — lies in that direction, over the horizon to us but very much visible to clusters we can see.

Imagine! It’s a sobering reminder that the Universe itself is literally bigger than we can see, with the majority of it forever beyond our ken.

And if your quota of weird isn’t yet sated, then ponder this: the expansion is accelerating. That means that objects we can see today, so distant they linger on our current horizon, will eventually fall away from view as the accelerating expansion beats out the velocity of the light they emit. They will literally move beyond the horizon and become invisible. In a sense, it’s as if the visible Universe is shrinking, the horizon getting closer to us every day. The physical Universe is getting bigger, but almost paradoxically what we see of it gets smaller. Someday, billions of years from now, only the closest of objects will remain visible.

Everything else will have sailed below the horizon. So we better take a look around while we still can.

[Incidentally, I cover this topic in more detail in my book Death from the Skies!, coming out in October, but already available for pre-order.]

September 25th, 2008 11:09 AM by Phil Plait in Astronomy, Cool stuff, DeathfromtheSkies! | 71 Comments »

People unclear on the concept

I get email. Because my site has been around a while it rises pretty high in Google searches, and that means all kinds of spam gets sent to me. Invalid offers to buy the site, requests for links, and such.

I just got this email, with the subject line "Link Exchange Request with Free Psychic Readings site":

Hi,

I saw your website’s page and felt that you have a wonderful resource which can be of interest to users on my website who are looking for free psychic readings. We will reciprocate you from one of our good theme based site.

My desired link is

[link redacted] Free Psychic Readings: 5Free Minutes @ [website name redacted] Get Live phone love relationship advice with Free Psychic Readings, Free Tarot Card Readings, Astrology Predictions, Numerology Readings and more on [website name redacted]!

I hope you will find my website another good resource to be added into your website.

Kindly revert back with your preferred linking code, hoping for a positive response from you.

Hmmm, a positive response? Well, I can positively say no.

Maybe these folks ought to actually, y’know, read my site first.

September 25th, 2008 8:09 AM by Phil Plait in About this blog, Antiscience, Humor | 24 Comments »

Shorter creationism

Pithy quote on creationism:

… Imagine how foolish you would feel if a thousand car mechanics tell you that you need to change the carburetor in your car and you keep insisting that they don’t know what they are talking about, elitist auto-experts that they are, because carburetors obviously don’t exist!

I am elitist. That is all.

September 24th, 2008 3:09 PM by Phil Plait in Antiscience, Piece of mind, Religion, Science | 83 Comments »

News: Hubble Shuttle launch delayed to October 14

I just received word that the launch of Atlantis to service Hubble has been delayed from October 10 to October 14. The nominal launch time will be 10:19 p.m. Eastern (US) time. The launch was delayed so that NASA could check out all the facilities after Hurricane Ike.

This also means that the launch of Endeavour has been delayed to November 16.

For more info, check out NASA’s Shuttle pages.

September 24th, 2008 12:09 PM by Phil Plait in NASA | 9 Comments »

The Mentalist: review

Last night was the premier of the TV "The Mentalist", what promised to be a skeptical look at psychics and police work.

Quick summary: it rocked.

More thorough summary:

Well, it did rock. It’s a crime/detective drama, but also has lots of humor. Simon Baker, dreamy Aussie, plays Patrick Jane, a man who used to be a relatively famous stage psychic, and is now a police detective. He has an incredible gift of observation, able to watch people’s behaviors, notice small background items, note things that are said, and put them together rapidly to form a picture of what’s happening around him.

"The Mentalist" is a different kind of crime drama. Baker is very engaging (especially, evidently, for my wife), and he does have a quality about him that makes him fun to watch. His character invokes sympathy right away, even if he is a bit of a pain in the butt. He’s confident, even a little arrogant, but funny and endearing. It’s hard not to compare him to the titular character from "House", though he’s not as grumpy.

I love love love his character. He hates so-called "psychics" — hates them. In one scene, he comes right out and says there are no such things as psychics! When he did that, Mrs BA, The Little Astronomer, and I all threw our arms over our heads, fists pumping the air! W00t!

But to the meat of this: I think a real skeptic is behind this show, someone who knows about the frauds, fakes, and evil people who claim to speak to the dead. Here’s why:

S P O I L E R S B E L O W

In a series of flashbacks, we see Patrick Jane as he was five years before, a stage psychic who uses all the fraudulent tricks to make people think he can speak to the dead. On a TV show, he also brags that he’s helping the police find a serial killer nicknamed Red John (most psychics make claims like these, but you will never, ever find a case that was solved by a psychic, or even aided by one). Jane brags about his abilities, and insults the serial killer, calling him ugly and small.

Red John’s signature

When Jane comes home that night, there is a note on his bedroom door… from Red John. The killer wasn’t happy about being insulted in the media by Jane, and so has exacted his revenge. The note says that when Jane opens the door to the bedroom, he’ll find his wife and daughter, dead. In an unusual demonstration of restraint by a TV show, the scene ends showing him opening the door, and we don’t see the bodies. Just a lurid smiley face on the wall, drawn in blood, Red John’s signature.

Obviously, this is when Jane dropped the psychic act and became a vigilante against psychics. It’s also where he joins the police force.

During the show, Jane talks to a psychiatrist because he can’t sleep well at night. When asked why not, he makes up a story about a childhood tragedy. We, the viewers, know the real reason: guilt over the death of his family. His own hubris killed them.

Now let me make an aside. The real tragedy of these blood-sucking "psychics" who "talk to the dead" is that they interrupt the grieving process. If you lose someone you love, it’s awful, terrible, and the pain is tremendous. But, over time, you heal. It takes a long time, and of course you never totally get over it, but eventually you can heal, you can move on. "Psychics" stop this process cold.

By making people believe that their loved ones are still around, still issuing pablum-like things ("I’m happy", "I forgive you"), they don’t let the grieving people heal. They are picking at the wound, keeping it open. Sure, people may feel better in the short term, but the healing process is short-circuited, and that’s very unhealthy. And it’s another in a long list of reasons why people who claim to talk to the dead are so truly evil.

And that brings us to the last scene in "The Mentalist". At the end, after solving the case using his amazing observational skills, Jane goes home. We see it’s the same house he lived in when his wife and daughter were killed five years earlier… but it’s totally empty. All the furniture, all the furnishings are gone.

Jane slowly goes up the stairs and into the bedroom. Like the rest of the house, it’s stripped clean. The only thing in it is a bare mattress on the floor. Jane lies down on it, and the camera pans around, showing the bloody smiley face still on the wall.

I was astonished by this. The character of Patrick Jane feels tremendous guilt — as well he should — over the death of his family. Because of this, he punishes himself by staying in the same house, removing all the trappings of a happy life, and by leaving Red John’s mark on the wall.

But remember, he couldn’t tell the doctor why he wasn’t sleeping. He couldn’t admit to being partly responsible for his family’s death. He was a psychic, and he interrupted his own grieving process.

Beautiful. The writing here was intelligent, thoughtful, and because of this irony based on skeptical knowledge of "psychics", right on the mark.

And, in my opinion — as you might guess — nailed how truly loathsome "psychics" are.

This was one of the most skeptical shows I have ever seen on mainstream TV, and I hope they can keep this up. It showed so many tricks, so many insights into how to defraud people that I would LOVE it if more people watched and absorbed this knowledge. My only fear is that, under pressure from TV suits, they somehow let Jane get over his guilt and forgive the "psychics" — after all, his skepticism is in some ways due to his major character flaw, so it’s not a big jump for the writers to do that. So many shows cop out that way; make the skeptics look like jerks, and make the antiscience followers look sympathetic, when in fact that is far, far from the truth. So many "psychics" are the ones who use people, defraud people, and use their emotional vampirism to get rich, rich, rich.

So I can’t say enough good things about "The Mentalist". It was well acted, well written, and the staging and direction were very good. Overall it was engaging, funny, and drew me right in.

But I think the most important part is that it spoke from a true skeptical standpoint. Jane gave many of the arguments I hear from other skeptics about many antiscience topics, and they come from the star of a mainstream show. And to see a skeptic who is portrayed as sympathetic, attractive, and even likable was a breath of fresh air from a medium — heh, medium — that falls all over itself to give the phonies, the frauds, and the fakes far more than their fair share.

I hope "The Mentalist" has a long, skeptical, and critically acclaimed run.

September 24th, 2008 11:09 AM by Phil Plait in Antiscience, Debunking, Piece of mind, Skepticism | 83 Comments »

Space X to try again this week

The private company Space X will try once again to get a Falcon 1 rocket into orbit. This fourth launch attempt could be as early as September 28!

The static firing engine test for the Falcon 1.

They just had a "static firing" a test of the engines with the rocket strapped down। Everything looked pretty good, but they detected a minor fault in the second stage liquid oxygen supply. They’ll be replacing a component in that system just to be safe. http://louis-j-sheehan.com

dust

Each morning I wake and open my eyes to a new day filled with things I can’t see. I’ve even grown to appreciate how much the unseen makes its presence felt throughout our daily lives. It has been this way since the dawn of time, but modern science has opened the doors to understanding the unseen worlds that crowd into our own and even allows us to manipulate some of them for our own ends. An endless silent babble of radio waves, massed armies of insects, long-gone planet-girdling ice sheets, endemic microbes, rivers of wind, and more all leave their stamp on the shape of my life in the course of 24 hours. Determined, I set off to unravel the mystery of my invisible day.

The Demons Within
8 a.m. I could pretend that I shoot out of bed bright-eyed and bushy-tailed, ready for another day at DISCOVER. But the truth is much blearier, an important part of which is the eradication of the first invisible presence of the day: morning breath. My mouth feels less than fresh as I yawn my way to the bathroom.

Morning breath comes mostly from bacteria that live in the mouth. More than 500 types of oral bacteria have been identified in people so far, and “we keep on identifying more,” says Patricia Lenton, an oral malodor researcher at the University of Minnesota School of Dentistry and a “calibrated breath odor judge.” While we are sleeping, the flow of saliva in our mouths decreases, leaving the bacteria alone “back there, just producing things, lots of sulfur gases,” Lenton says. These orally produced sulfur gases—with names like hydrogen sulfide, methylmercaptan, and dimethyl sulfide—plus some other miscellaneous by-products of bacterial metabolism, account for 90 percent of bad breath that can’t be traced to an outside cause. Meanwhile, foods such as garlic and onions release sulfur compounds as they are digested in our intestines. Some of these compounds are absorbed into the bloodstream and pass into the air in our lungs. As we exhale, we breathe them out.

It’s also through the lungs that changes in blood chemistry caused by disease can affect the odor of our breath. “Diabetes is a good example. When people have uncontrolled diabetes, they can have a really sweet, fruity smell in their breath,” Lenton says. Researchers are even working to develop tests for breast cancer and organ transplant rejection based on the bouquet of a patient’s breath.

Most odor-producing bacteria live on the tongue, not the teeth, so I give my tongue a few good scrubs with my toothbrush before continuing my morning routine.

Scrutinizing the Jet Stream
9 a.m. I’m ready to leave, checking out the window for the effects of that all-time-classic invisible entity, the wind. I’m not looking for the effects of just any old gust of air. The specific wind that is going to determine whether I’ll have to put on a jacket is one that weather watchers didn’t even know existed a century ago.

It’s called the polar jet stream, and as it writhes eastward across the North American continent, it can bring storms in its wake or herald an unseasonable change in temperature—north of the jet stream lies cold, Arctic air, while to its south are warmer conditions। In summer months the polar jet stream flows mostly across Canada. During the winter it dips as far south as the U.S. Gulf states. http://louis-j-sheehan.com

Jet streams occur at very high altitudes—30,000 to 40,000 feet—which is why they were not definitively identified until World War II, when pilots noticed intense headwinds during long-distance military missions. The heart of a jet stream is a relatively narrow band of strong wind a few hundred miles wide that can reach speeds of more than 200 miles per hour. Jet streams draw their energy from the rotation of the earth and the difference in temperature between the equator and higher latitudes. Without jet streams, “it would be a pretty boring place,” weatherwise, says Klaus Weickmann, a meteorologist at the Earth System Research Laboratory of the National Oceanic and Atmospheric Administration (NOAA) in Boulder, Colorado.

Small changes in the jet stream as it passes overhead can create stormy weather at low altitudes. For example, “if you have a low-pressure area aloft, then you will tend to produce low pressure at the surface ahead of it,” Weickmann explains. “That particular [atmospheric] structure is very efficient at extracting available potential energy and converting it into kinetic energy.” This kinetic energy manifests itself in the kind of high winds and rains that can turn a day into a washout. From what I can see out my window though, the weather appears to be pretty calm, so I decide to leave my jacket at home and gather my things. I open my building’s front door and look up at the slight hill I have to climb to my subway stop.

Glacial Moment
It’s not much of a slope, but this hill, and others like it, are evidence of the ancient forces that ultimately brought me and more than 8 million other people to live in New York City. At the peak of the last ice age, some 20,000 years ago, right outside my front door was a frozen glacier wall that rose as high as 300 feet, the southern edge of a vast ice sheet that covered Canada and the northern part of the United States. “Glaciers act as a plow, pushing stuff ahead,” says Sidney Horenstein, a geologist at the American Museum of Natural History in New York City. The edge of America’s ice sheet—marked by a line of rubble called the terminal moraine—ran along Long Island. When the earth warmed and the glacier receded, the rubble was left behind as a series of low hills. Look at a map of New York City and in the boroughs of Brooklyn and Queens (located on the west end of Long Island) you can see that chilly history encoded in the names of today’s neighborhoods: Cobble Hill, Brooklyn Heights, Park Slope, Forest Hills. Southeast of where I live, water from the melting edge of the glacier flowed over the landscape, depositing layers of sand and silt and leaving behind areas with names such as Flatbush and Flatlands. “The community names have meaning,” Horenstein says.

But the biggest impact on New York’s destiny came from the glaciers’ ability to erode, not build, landforms. A glacier “acts as sandpaper because it has rocks embedded in its base…so as the glacier moves, it’s deepening valleys and smoothing off the tops of hills,” Horenstein says. As the glacier moved south toward the future location of New York City, it widened and deepened the Hudson River valley. “The Hudson is the southernmost fjord in North America,” Horenstein says. When the first Europeans explored the river in 1609, they found in it an ideal trade route that penetrated into the continent. The glacier’s deepening of the Hudson also made New York Harbor a snap for trans-Atlantic shipping to navigate.

+++

These geologic advantages—a terrific natural harbor and an easy transportation route into the interior—allowed an active trading outpost to be established on Manhattan Island by 1625. Over the next four centuries, this blossomed into the international financial and cultural powerhouse that is New York City today—one that still draws people from all over the world to settle here.

Magnetic Attraction

There’s a lot of worry about what we might be breathing while commuting, so I borrowed an air sampling pump to find out.

It’s only a few minutes’ walk up the hill to the subway, and I descend the steps and enter the realm of magnetism. Magnetism is what gets 5.4 million passengers around New York City’s subway system every day, starting with the MetroCard I swipe at the turnstile to enter the system. My MetroCard has a stripe made from a slurry of barium ferrite particles painted onto the card. The stripe encodes a couple hundred bytes of data in magnetized patterns. The data are read by the subway turnstile, which decides whether I have paid for the trip. The turnstile also keeps a record of the card’s unique identification number and the time and date the card was used, regularly uploading this information to the New York City Transit Authority’s central computers. (The local police have found this inconspicuous record-keeping handy in implicating or exonerating suspects in criminal cases and have even used it to trace notorious fugitives such as Peter Braunstein, who sexually assaulted a woman after pretending to be a fireman checking for smoke damage in her building, according to newspaper accounts.)

But where magnetism really reigns supreme is in the motors that drive the subway trains. The New York City subway system supplies power to its trains via a third rail charged with about 625 volts of direct electric current (DC). A device called an inverter turns this into alternating current (AC), which is fed to the motors underneath each car. Inside the motor, the AC electricity flows through coils that surround the rotating core of the motor. The alternating current creates a constantly changing magnetic field and, through some clever engineering, magnetizes the core of the motor as well. Magnetic attraction pulls the rotor toward one coil and then to the next. The changing magnetic field ensures that the rotor will never come to rest, and its strength—thousands of times more powerful than a typical refrigerator magnet—provides the necessary push to keep the train moving.

Iron Lungs
Driven by its motors, my train rumbles into the station, clattering along the tracks. It’s about a 35-minute commute to my stop at 14th Street and Sixth Avenue in Manhattan, and from there a five-minute walk to DISCOVER’s offices. There’s often a lot of worry in New York City about what we might be breathing into our lungs while we’re commuting and otherwise out and about. As is common around the country, New York State’s Department of Environmental Conservation routinely monitors the levels of ozone, carbon monoxide, sulfur dioxide, nitrogen oxides, and particulates in the air. Together these measurements give a pretty good snapshot of the health of the air, known as the Air Quality Index (AQI). Anyone can get a real-time report on the AQI in his or her area by visiting airnow.gov. But I was interested in finding out what else I might be breathing, so I borrowed an air sampling pump from Jennifer Richmond-Bryant, an assistant professor of environmental and occupational health sciences at Hunter College in New York City.

Fortunately for me, I’m in no danger of metal poisoning—nearly all the elements we tested for, including lead, arsenic, and chromium, weren’t present at detectable levels. But two were detectable—iron and calcium. The iron comes from my time in the subway, generated from “wear and tear on the wheels and on the tracks,” which produces tiny iron particles in the air, Richmond-Bryant explains. The calcium comes from aboveground: There is “a decent amount of calcium in concrete,” she says. The concrete gets ground up “when people drive over it or when construction is going on,” and small amounts of it are released into the air. But New Yorkers needn’t worry—iron and calcium are not considered hazardous air pollutants by the EPA.

Radio Free New York
As I stroll along 14th Street to work, I’m also wandering through an invisible electromagnetic bedlam. Indeed, if I could see radio waves, the top of the Empire State Building 20 blocks north of me would be lit like a kaleidoscopic flare, illuminating the entire city. The Empire State Building is host to an array of antennas that are taking advantage of the building’s 1,454-foot height—to the top of its lightning rod—to broadcast a bevy of radio and television stations.

But it’s not just radio and TV signals that are in the air. Cell phones, Wi-Fi-enabled laptops, walkie-talkies, and more are all adding to the bedlam. To prevent transmissions from interfering with each other, the Federal Communications Commission and the National Telecommunications and Information Administration tightly regulate the use of every radio frequency on the electromagnetic spectrum. With a device known as a spectrum analyzer, it’s possible to visualize just how the spectrum is being used. I borrowed one that could detect signals from 100 kilohertz (kHz), just below the frequency of long-wave radio stations, up to 3 gigahertz (GHz), somewhat above the 2.4 GHz portion of the spectrum used by Wi-Fi connections (see “Radio Ways,” below). If you have a Wi-Fi-enabled computer, you can create your own poor-man’s version of a spectrum analyzer. You’ll need a piece of software like Kismet or KisMAC, which you can find free online. This software taps into your Wi-Fi card’s radio and displays all the signals from nearby Wi-Fi base stations, along with the frequency, or channel, that they are broadcasting on. This can come in handy if you’ve noticed a slowdown in your wireless connection speed—it might be that neighbors have set up a new Wi-Fi base station that is using the same channel as yours, resulting in interference. If you spot an unused channel with Kismet or KisMAC, you might want to adjust your base station so that you are connecting without interference.

It’s not just radio and TV signals. Cell phones, Wi-Fi laptops, walkie-talkies, and more are adding to the bedlam.

Software Shock
Once I finally reach DISCOVER’s office, around 10 a.m., the first thing I do (after fixing myself a cup of tea) is fire up my computer and check my e-mail accounts. The difference between a computer that is useful and one that is an expensive paperweight is, of course, software. A piece of software is essentially a list of instructions that tell a computer what to do. And these days, computers, along with their software, are everywhere.

If you’ve ever struggled to understand how a piece of software works, you are not alone. In fact, simply checking for new e-mail triggers a cascade of activity so complex that no human being could ever completely understand all of it. Subsystem interacts with subsystem as electrons surge and flow through microchips that operate according to the dictates of semiconductor physics. How is it, then, that every time you log on to the Internet, there’s a cool new Web site that seems to work just fine, despite not being programmed by a crack squad of Nobel laureates?

+++

The key to making it all work is the concept of layers. The top layer is the application that you’re using at the moment—a word processing application like Microsoft Word, say. The word processing application talks to your operating system, like Vista, a lower layer that handles requests to do things like save a file. In turn, the operating system talks to the hardware, such as your central processing unit, which has the responsibility for actually storing the file. And each one of those layers is composed of many sublayers. “It’s layer upon layer upon layer.…To me, the most marvelous thing about it is that all this stuff is transparent,” says Warren Harrison, a professor of computer science at Portland State University in Oregon. What Harrison means by “transparent” is that each layer makes the messy details of what it’s doing invisible to higher levels. This approach means that your word processor can just say “save this file” without worrying about the low-level details of how to organize the bits on your computer’s hard disk. Transparency also “gives us division of labor. So I can specialize in writing network software, and I don’t have to worry about knowing how to write a good user interface. Or, conversely, I can specialize in writing user interfaces and I don’t have to worry about network software,” Harrison says.

I obtained a measure of bacterial activity from a swab taken at a water fountain near our offices.

This principle of transparency extends to the Internet. Whenever I check the online weather report or my Facebook profile, the request passes from computer to computer until it reaches its destination. Yet as I sit at my computer, all these computers hide their presence as best they can, so it looks as if I have a direct computer-to-computer connection with the Web site of my choice.

Rocky Foundations
1 p.m. Lunchtime. I go out to grab something at a gyro stand down the street. I’m surrounded by buildings that are rather on the short side for Manhattan, rising only 10 or 11 stories. North of 33rd Street and at Manhattan’s southern tip, buildings that are over 40 stories high are common, giving the city’s skyline a saddlebacked appearance, as building heights drop sharply between the two clusters of towers. Another quirk of geology is to blame. The city’s bedrock, formed through a cataclysmic series of tectonic collisions 550 million years ago, rises close to, or even pushes through, the surface in some parts of the city, creating the perfect foundation for very tall buildings. In other parts—such as near 14th Street, where I am standing, waiting for my lunch—the bedrock is covered by up to several hundred feet of dirt and gravel. This looser material can’t support as much weight as the bedrock, resulting in more squat buildings.

The Microbial Manifest
Lunch in hand, I return to the office. The rest of the day is spent in meetings and working at my computer. Six o’clock rolls around and I descend again into the subway. The train is usually pretty crowded, so I often have to stand and hold on to a metal railing for the trip. It’s when the railing is still warm and slightly greasy from an earlier passenger’s hand that my thoughts turn to the subway’s microbial population. Vincent LaBombardi, director of microbiology at Mount Sinai Hospital in New York City, is reassuring, though: “Most organisms that you find are not pathogenic; they’re typical environmental bugs that you would not be terribly surprised to find, like corynebacterium species and bacillus species.” LaBombardi does note that also to be found is “the cold virus and other types of the adenovirus and whatnot—but that is no different from anyplace else.”

Just to make sure, I swabbed a subway car handrail and had it checked for two bugs that are often in the news lately, E. coli and staph bacteria, as well as for a general measure of bacterial activity, known as the standard plate count, or SPC. The E. coli and staph test came back negative, and the rail’s SPC count of 480 compared favorably with the SPC of 200,000 that was obtained from a swab taken at a water fountain in a park near DISCOVER’s offices.

On the less reassuring side, LaBombardi says that in New York City tropical diseases are common: “We have a lot of people who travel, and they bring back souvenirs. So we see malaria; we see many parasitic infections.” But his big worry is drug-resistant bacteria. New York has “more strains that are resistant to antibiotics” than do other parts of the United States. For “some of these bugs [such as enterococcus] we have no drugs left,” he says. “They’re totally resistant to everything now.” Hand-sanitizing gels do not get rid of spores such as those belonging to Clostridium difficile, “a big pathogen” that can cause diarrhea and inflammation of the colon. But old-fashioned hygiene makes a good defense—LaBombardi recommends simply washing hands regularly with soap and water.

Picture Platters
Once home, therefore, I make sure to wash my hands before fixing dinner. My wife, Annie, and I settle down to watch a DVD. DVDs—like CDs before them and the Blu-ray discs that will eventually replace them—are a form of optical media. Beneath the plastic surface of the DVD, tiny pits and level spots called lands are arranged in a spiral with a 0.74-micron pitch about the size of an average bacterium. These tiny pits and lands encode digital zeros and ones. The DVD player spins the disc, and as it rotates, the spiral is scanned by a laser beam, which acts much like the needle in an old record player. The laser light used in DVD players operates at a wavelength of 650 nanometers (nm), which means it has a visible red color. Blu-ray discs squeeze more information onto the same size disc as a DVD—up to 50 gigabytes on a typical disc, compared with about 8 gigabytes for many movie DVDs—by using a data spiral with a pitch of just 0.32 micron and a 405-nm laser beam. Although 405 nm corresponds to a violet color, it is referred to as blue—hence the name of the format.

The Arthropod Army
Soon enough it’s midnight and time for my eight hours of shut-eye. I climb into bed, not thinking of the extensive colony of tiny arthropods lurking in my pillow and mattress. These arthropods are dust mites, and unless you’ve taken exceptional measures, they’re in your pillow and mattress too. Dust mites “need places to hide, and they like places with higher humidity,” says Jason Rasgon, an assistant professor of microbiology at the Johns Hopkins Bloomberg School of Public Health। “They’ll definitely be in mattresses and pillows; they’ll be in the carpets. They can be pretty much every­where.” Dust mites feed on organic detritus: “Household dust is made up of dirt and shed skin cells, and they like that kind of stuff,” Rasgon says. Male dust mites live for about a month. The females live about twice that and lay about 30 eggs in their lifetime. Both sexes are less than 420 microns long and look like specks of dirt to the naked eye. There can be as many as 19,000 dust mites in three-hundredths of an ounce of dust (but a few hundred is more likely). http://louis-j-sheehan.com

Dust mites are a subject of increasing health concern because they can be highly allergenic. According to Rasgon, people can react not only to the mites themselves but also to their exoskeletons, which are shed as the mites molt during their life cycles. And then there’s frass, which, Rasgon helpfully explains, is “mite poop.” Dust mite allergens can trigger serious asthma attacks and other allergic reactions. Some severe sufferers have to cover their mattresses and pillows with impermeable material.

For me, though, it’s head down and off into the realm of sleep. Exactly what happens inside our skulls when we are dreaming is still an area of active debate, but my nighttime visions are anything but invisible to me as I slumber, resting and gathering my forces for another day.

http://Louis-j-sheehan-esquire.us

Try not to think about a white bear and suddenly there it is, haunting your thoughts. A new study indicates that attempting to suppress specific thoughts also has a delayed effect by bringing them out in dreams.http://Louis-j-sheehan-esquire.us

The findings elaborate on Sigmund Freud's century-old idea that wishes suppressed during the day find expression in dreams, says Harvard University psychologist Daniel M. Wegner. Now, it appears that consciously squelched thoughts often reappear in dreams, whether or not those thoughts incorporate wishes, he says.

Wegner and his coworkers studied the dreams of 295 college students. Before going to sleep at home volunteers spent 5 minutes writing down their thoughts. The participants had been given one of the following instructions: Don't think about a specific person whom you either regard as a friend or have a crush on, do think about that person, or simply write his or her initials.

Each type of exercise before sleep prompted many volunteers to report, upon waking in the morning, that they had dreamed about the person they had thought about or tried not to think about the night before, the researchers say in the April Psychological Science. About one-third of those who tried not to think about the designated person then dreamed about him or her, compared with only one-quarter or so of those in the groups encouraged to think about that person or asked to write initials.http://Louis-j-sheehan-esquire.us

Wegner says that the findings have no bearing on Freud's controversial notion that unconsciously repressed thoughts, like consciously suppressed ones, reappear in dreams.