Monday, April 30, 2012

Another step towards Big Brother

kw: politics, policy, internet, privacy, legislation

An act called CISPA (Cyber Intelligence Sharing and Protection Act) passed the U.S. House of Representatives yesterday, and now it goes to the Senate. Proponents say, "Oh, no, it won't impact the privacy of citizens," but we know that's a sham. It is interesting to them precisely because they know it erases most of our privacy protections. See this C|Net article for a good analysis.

I find that Republican congressmen voted in favor 206 to 28. I am ashamed of them. I am a registered Republican, but this sure isn't the party of Abraham Lincoln or Theodore Roosevelt any longer. I may have to become a Libertarian.

I remember the first Terabyte database, which cost about a million dollars to set up in the early 1980s. It was commissioned by the Mormons for genealogical record-keeping. My colleagues and I were joking that if a disk drive with "infinite" capacity were invented—we called it the God file—the government would order two of them. I recall saying, "Sears and GM would be next in line". Today anyone can buy a multi-terabyte disk for about $100. The Google Earth image base is a multi-petabyte (thousands of terabytes) product, and Google is only one of a number of both corporate and government entities to have file bases approaching an exabyte (a million terabytes) in size. The NSA is building a multi-exabyte data store. So just where are they going to get data to fill it? You guessed it: the Internet, and CISPA is an integral part of the process. It gives them the right to "ask" for data dumps without breaking any laws, because CISPA removes or supersedes most current legal protections. The President has stated he will veto it if the Senate passes it. That's one thing he could do that I would like a great deal!

Sunday, April 29, 2012

Mount Cuba 2012

kw: photographs, wildflowers, wildlife

We spent a pleasant hour at the Mount Cuba Center in Hockessin, Delaware this afternoon. The Center is famous for preserving and studying the native vegetation of this region. Less well known than some of the DuPont family estates such as Longwood Gardens, it is the only one I know that has solely native plants on display (except in the Round Garden where there are tulips and delphiniums).

Today was special: because of the mild winter, the Trilliums are actually past their prime, the dogwoods as well, but the wild azaleas are just getting into full bloom (see below. I am still getting used to the new blogging software).
Lavender Trilliums with Bluets

It was also special because they had two people from a wild bird rehabilitation center (I didn't catch its name) bring in some raptors (hawks and a falcon), and this vulture, to show us. Each of the birds shown is injured in some way and could not live in the wild. The vulture is 20 years old and was raised as a pet, so it is much too trusting around people.
Closeup of wild Azalea
A pleasant day, with perfect weather for a long walk in the woods and gardens.

Friday, April 27, 2012

A head covered with foam

kw: observations, products, analysis

I am sure you've seen the ads for shampoo, where someone squeezes out an ounce or two of shampoo and lathers up. You see lather flying everywhere. I use one of those advertised shampoos, and I use a drop about the size of a nickel. I began to wonder, just how much does it take to clean my hair?

For most of us, we're really trying to remove oils that our scalps produce, and the amount is really quite small, even for someone with "oily hair". The surfactants in shampoo bind to an amount of oil roughly equal to their own volume. I haven't found any record of some number of milligrams or micrograms of oil that is "normal", so we'll have to make a reasonable estimate.

I have found by observation that if I get my hair very clean, it is pretty flyaway (even if it is no more than two inches long). Within a few hours, it gets more manageable when I brush or comb it, from the first coating of oil. So I estimate that enough oil is produced in about two hours to form a monolayer on all the hair, and production probably continues at this rate all day. By day's end, the hair is not noticeably oily, because a dozen monolayers is still not much oil. Let's calculate how much.

When I had a full head of hair, I kept it about as long as I do now, some 5 cm (2 inches). My hair was brown (getting gray these days), so the number of hair strands was about 50,000. That comes to 250,000 cm or 2,500 m of hair (8,200 ft). Brown hair averages about 60 µm in diameter, so its circumference is about 190 µm, or 0.00019 m. Multiply by 2,500 to get 0.475 m². These are rough calculations, so we'll round it to half a square meter. Just by the way, only about half my scalp has hair now, but the bald portion gets oily, so oil production hasn't slackened off.

To get the volume of one monolayer, now we just need the thickness. Skin oils are hydrocarbon based, so they'll have a sausage shape, with a diameter in the range of half a nanometer, or about 5Å (5 angstroms). 0.5m²×0.5nm = 2.5E-10 cubic meters, or 0.00025 cc, or 0.25 cubic mm. Twelve such volumes amount to 3 cubic mm.

So, the amount of oil you need to remove, if you wish to remove it all, is about 3 cubic mm. That is a dot the size of a pin head. Can we really get away with using a similar amount of shampoo? Would it really work? I have yet to make the experiment. My nickel-sized dollop of shampoo is about half a cc, or 500 cubic mm. I'll try smaller and smaller amounts to see how much does an effective job. I suspect there is a lot more at work here than just oil removal.

Thursday, April 26, 2012

Staying connected

kw: computer security

I haven't had a reason to visit the FBI web site before, but a newspaper article gave me one. Some clever cybercriminals set up a web server warehouse in Eastern Europe and propagated a virus that caused computers to send internet page address requests to their data warehouse to be resolved. The page addresses returned had more ads or different ads than the "normal" page. The scam owners made a few millions from the ad agencies they favored in this way.

To take down this operation, which amounted to infections of at least half a million computers worldwide, the FBI contracted a company to set up a mirror site running the same server software, then arrested the Eastern Europeans and closed down the original site. This has been going on for months now, but the mirror site is about to be closed down, on July 9 (don't you love how judges pick dates?). From that date, an infected computer will be unable to access the internet at all, because it will be sending requests to a set of Domain Name Servers (DNS's) that no longer exist. One side aspect of the infection is that antivirus updates are blocked, so other malware has probably infected the computer.

The FBI's contracting company has a tool to detect an infection, and a procedure to remove the infection if it is found. There are a couple of web addresses being printed in newspaper articles. I decided to go through the FBI and see what they offered. First, I checked my computer to see if an antivirus update would work. It did, so I had some initial comfort that I was unlikely to be infected.

To do what I did, do the following:
  • Enter the URL . I haven't provided a link here because it is safest if you type in the URL directly.
  • At the upper right they have a search bar. Enter dcwg; you are looking for articles about the Domain Change Working Group, the contractor working with the FBI.
  • From the list returned, the second or third link will be to a page "Check to see if your computer is using rogue DNS". Click on that.
  • There is a set of links. Which one you use depends on where you are in the world, and your language. Click one of them.
  • You will then see either a green box or a red box. The green box tells you your computer is OK. The red box informs you how to remove the infection it found. I haven't had to do so, so you are on your own from here.
I thought of using some screen shots in this item, but decided they could too easily be used to promulgate a meta-scam. Sometimes good old-fashioned text is best.

Tuesday, April 24, 2012

The zipper is just the beginning

kw: observations, history

Today's Google Doodle marks the 132d birthday of the inventor of the zipper, Gideon Sundback. Prior to about a century ago, which is also prior to the use of elastic in waistbands, you had to undo a couple of buttons to get trousers off, which could be a problem if you were in too big a hurry!

But there is more to the day than sartorial developments. The Internet is a wonderful library, and when I get a wild hair about something, its resources astound me. In particular, there are dozens of "this day in history" sites. The best that I've so far found is Some tidbits from its archive:
  • 2005 – Cardinal Joseph Ratzinger becomes Pope Benedict XVI.
  • 1996 – Highest scoring baseball game in 17 years: Twins 24, Tigers 11.
  • 1990 – West and East Germany agree to merge their currency and economies (to take place on July 1).
  • 1981 – Introduction of the IBM PC. Prior to this you had to build one from a kit.
  • 1969 – Paul McCartney says there is no truth to rumors that he is dead (Mark Twain said it better 72 years earlier: "Rumors of my death are an exaggeration").
  • 1953 – Queen Elizabeth II knights Winston Churchill (and about time, too).
  • 1928 – A patent issued to Reginald Fessenden for the fathometer, a sonar device that measures depths underwater. This beats lowering a weight on a marked rope, which may or may not hang vertically.
  • 1907 – Milton Hershey opens Hersheypark in Hershey, PA. Initially, it was exclusively for employees.
That takes us back a century. These are just a few of a couple hundred items from which I could choose.

Monday, April 23, 2012

Are all viruses pathological?

kw: viruses, medicine

In a recent article in Wired (found here at, the question is raised, if we develop broad-spectrum antiviral medications, should we use them? Since the publication of that article just a month ago, about sixty online articles have explored the idea. You can find them and other similar articles by searching for "beneficial viruses" (include the quotes for a phrase search).

Are all viruses bad? Do they all cause disease?

When bacteria were first discovered, it was thought by many that all "germs" were bad, and once antibiotics began to be developed in the 1930s, they were used indiscriminately for any sign of infection. Such things as upset digestions, diarrhea and bloating were thought to be unfortunate side effects. But it didn't take long for our "internal flora" to be discovered, and we are still learning how important they are. The list of beneficial bacteria, some residing in our gut, some on our skin, some lining our sinuses, and others who knows where, continues to grow. By current estimates, 90% of the cells in a "human" body are bacterial, though they make up no more than 2% by weight.

It is no more than a decade or two since it was discovered that in a typical sample of ocean water, there are a thousand virus particles ("virions") for every eukaryotic cell, most of them being bacteriophages. Or, I should say, denizens of bacteria, because it is not known whether a virus residing in a bacterial cell is there to kill it or in some way to help it. We know that phages are pathological to bacteria, just as many viruses that infect us and our animals and plants are pathological. But we are just beginning to learn of viruses that are found in cells yet don't seem to cause disease.

Wouldn't it be ironical if we developed a broad-spectrum antiviral, tried it out, and found it to be universally fatal to the mouse, monkey or man into which it was introduced? Fatal why? Because it eliminated a virus to which we play host, that performs a required function! Fortunately, while our internal flora of bacteria may be helpful, none is required for us to continue living. Strains of supposedly germ-free mice have been developed, and though they live differently than ordinary mice—mainly in that they need to eat more—they seem to live well enough. But we don't even know if those mice are virus-free. We don't yet know how to produce a virus-free mouse, or if it is possible to do so.

The days of effective antibiotic medicines are drawing to a close. We are being forced to take another look at an older, effective, if cumbersome, therapy using bacteriophages. The problem is, these are very specific. There are no broad-spectrum phages. A second kind of therapy (this is very early days) is the anti-bacterial bacterium: using an overwhelming dose of our good bacterial companions to drive out those we don't want.

This makes me wonder, are there anti-viral viruses? Are we actually host to any (or many?) viruses, not yet discovered or studied, that keep pathological viruses in check most of the time? Just as certain bacterial are becoming known as essential ingredients in our immune function, there may also be immune-functional viruses.

This just scratches the surface of the questions we need to be asking about viruses and our relationship to them. There is a long way to go, and we ought to be careful how we use new "miracle" drugs, lest the miracle we perform is to our own detriment.

Sunday, April 22, 2012

A nine by any other name

kw: words, religion, meanings, origins

I have had nearly no contact with monasticism, so it is only recently that I learned to what extent Catholic piety is tied to the old Roman concept of time. In the daily discipline of many monastic orders, there is a round of eight sets of prayers. With their approximate time of day they are
  • Vigil – pre-dawn
  • Laud – sunrise
  • Prime – early morning
  • Terce – midmorning
  • Sext – noon
  • None – midafternoon
  • Vesper – early evening
  • Compline – sunset or late evening
For a monk, you could say that "prime time" is about the time the rest of us are just getting up. But let us focus on the fourth, fifth and sixth: terce, sext and none. These words, compensating for two millennia of phonetic drift, are from the Latin words for 3, 6 and 9. In Roman Europe, sunrise marked the start of the day, and was "zero hour". A timekeeper would note when the Sun crossed the meridian, that is, when it was due south, and signal noon, or six hours into the day. Sunset was hour twelve, but was also zero hour for the night watches.

In the monastic orders that keep the old way, one or more timekeepers have the job to ring signal bells when these standard hours occur, so the monks can all pray the office of each hour. This is immortalized in a children's song:

Are you sleeping, are you sleeping,
Brother John, Brother John?
Morning bells are ringing, morning bells are ringing:
Ding, ding, dong. Ding ding dong.

In French it is more revealing:

Frère Jacques, Frère Jacques,
Dormez vouz, dormez vouz?
Sonnez les matines, Sonnez les matines!
Din, dan, don. Din, dan, don.

In the third line, the sleeping brother, who is late with his signal, is exhorted to ring the bells! (or else!!) Poor Brother John. The ninth hour of the night, or three AM, it is tough to keep watch for the rising of a certain star that informs him it is time to ring the Vigil bells. Three other astronomical phenomena, sunrise, Noon, and sunset, are at least easier to anticipate.

I haven't learned how they determined, in any accurate way, the other times. An hour glass would only work for part of the year, because in early days, the lengths of the hours were variable, tied to the interval between sunrise and sunset, and for night watches, the opposite interval. Of course, computers can keep accurate track of any time scheme they like, for more modern monks!

Now I turn to the word that started all this investigation: None. This is not the pronoun "none", an Old English word that means "not one" and rhymes with "fun" or "done". Instead, this word rhymes with "phone" or "stone", and originates from Latin "nonus" meaning nine. Sometimes written "nones", it initially referred to the ninth day of some sequence, such as the ninth day of the month, or of a long celebration. Only in the Sixteenth century was it added to the Divine Office as a prayer-time at three PM or thereabouts.

I find it an amusing coincidence that the pronoun "none", meaning "not one", rhymes also with "nun". Thus in spelling "none" (the pronoun) matches "none" (prayer time at the ninth hour), while in pronunciation "none" (the pronoun) rhymes with "nun" (a woman with a religious vocation).

Saturday, April 21, 2012

Kepler keeps amazing

kw: astronomy, exoplanets, spacecraft

I suppose this article is the best place to go first to track the Kepler mission to find exoplanets. It is being kept up to date, and was last edited just a couple of weeks ago. Before the Kepler mission began, we knew of perhaps one or two planets that were Earth size (out of a few hundred), and one or two that might be in their star's habitable zone. So far the Kepler team has identified more than 2,300 probable planets, and about a tenth of them are similar in size to Earth. The number of planets found in their host star's habitable zone is nearly fifty, so far.

 A most exciting recent discovery is two planets around a star dubbed Kepler-20, with sizes estimated as shown, both within the star's habitable zone. The smaller one may be hot like Venus. It will depend on the atmosphere. The larger one, a bit farther out, may be a little cooler than Earth, or very similar to Earth.

It is much too early to tell what kind of atmosphere they have. Whether either of them could have life depends entirely on that.

The Kepler mission is going on four years old already. It has revolutionized our understanding of planetary systems. Considering all that we have learned from observing just 1/400 of the sky, and only stars brighter than visual magnitude 16, there are many, many planets waiting to be found, and a great deal we can learn about planetary system evolution and composition.

The Kepler spacecraft observes more than 100,000 stars twice per hour, recording their brightness with great accuracy. The "light curve" for each star is examined, both by software and by volunteer "citizen scientists" (yours truly included), to find small dips in the stars' brightness that will herald the transit of a planet across the face of the star, as seen from Earth. Close-in planets that zip around their star in a few days will transit in a couple of hours. Transits of planets in orbits close to the size of Earth's orbit about the Sun will take half a day more or less. In the list of stars for which I have reported suspected planet transits, three have been listed as planet "candidates"; the team is very cautious. To get involved, set up an account at

Friday, April 20, 2012

No off button

kw: book reviews, nonfiction, essays, e-mails, humor

This may not be the dumbest thing to go viral, but it must be the simplest. The little article titled "overdue" at 27b/6 is really what went viral: David Thorne wrote a humorous piece in the form of a stack of e-mails back and forth with a creditor: he tried to pay a bill by sending the picture of a spider. When they wouldn't accept it, he asked for it back, then added the missing 8th leg and sent it again. They wouldn't take it, so he asked them to send it back.

Thorne's book the internet is a playground: Irreverent Correspondences of an Evil Online Genius is a collection of articles and essays (loosely so called) and e-mail stacks from the web site. There are a few stock characters, such as Simon, who gets David involved in several humorous scrapes, such as camping trips to nowhere; Thomas, whose big head is the focus of the fun; and Shannon, who must be a receptionist or similar sort of clerk at the design agency Thorne claims to work for.

As the articles (etc.) make clear, the author's primary goal in life is to mess with as many minds as possible. He is unfailingly kind, in a knife-twisting sort of way that drives his correspondents (all of them imaginary, I suppose) right up the wall. I realized he is dallying with the boundary between reality and delusion, quite purposefully: His writing has the obsessive-and-just-won't-stop quality of a schizophrenic's word salad, but actually makes more sense.

It is not certain just where Thorne lives. The "About the Author" blurb inside the book states that he lives in Adelaide. The one on the back cover says he lives in Virginia. I wouldn't put it past him to live somewhere else entirely. It's in keeping with what-all else he has done.

Thursday, April 19, 2012

Dog 4 dinner

kw: food

There was a brief flurry the other day, about a quote from President Obama's book that he had once eaten dog, and a few other "delicacies". Let's not be too critical here. He was in Indonesia at the time, a region where you can buy dog meat at the corner market.

I once had a Cuban housemate. One day when it was his turn to cook, he made a delicious stew. When we were done, he let us know it was dog meat. He had bought it in Los Angeles, not far from where we lived.

We need to understand, there is hardly anybody out there kidnapping Fido for the larder. People raise certain breeds of dog for food. It just happens to be rare in the United States…rare but not unknown. I mean, there are several people I have known who raised rabbits for food. If you have a rabbit for a pet, I can understand a bit of squeamishness about eating its cousin. But meat is meat, as long as it isn't "long pig" (an old euphemism for human meat).

Wednesday, April 18, 2012

Spending too much, as usual

kw: deficit spending

I have been hearing much, pro and con, about the Federal deficit and the danger in which it puts us. No doubt, we are mortgaging the future of our children, but that is nothing new. Take a look at this chart, in which the dollar deficits are divided by GDP (the chart is from a blog post at Daily Speculations):

I believe the vertical axis is in percent; the trillion dollar deficit in 2010 was about one tenth of the ten trillion dollar GDP. What saved us from the giant deficits of the WWI and WWII eras of pre-1920 and pre-1946? Inflation. As someone about to shift from gainful employment to a nearly fixed income (pension plus social security), I certainly hope we don't get inflation rates that match those of the Carter years and the late Nixon years. If Reaganomics did nothing else, it ensured at least three decades of inflation in the 2-3% range, and sometimes less than 2%. I can handle twenty or thirty years of 3% inflation, but not much of 15% or so!

Thirty years at 2% is a factor of 1.8; at 3% it is 2.4. To get to 2.4 at 15% takes a mere six years and four months. But our children and grandchildren, absent high inflation, are going to be paying off the Bush-Obama deficits for decades to come.

I guess what I find surprising is that the recent deficits aren't higher than they are, given that we've been fighting two (and briefly, three) wars. On one hand, I think WWIII started twenty years ago. On the other, it is clearly a different kind of war, a low-grade war of attrition. At present, it is hottest in a certain part of Afghanistan, where a determined wing of the Taliban has decided (rather foolishly) to start driving NATO out, rather than wait for NATO to creep away on its own, following the lead of our Quisling-in-Chief. I expect the timetable of withdrawal to change dramatically in the coming months, and it will likely affect the way the election in November goes, though I couldn't hazard a guess which way just yet.

Tuesday, April 17, 2012

The dog at the head of the class

kw: book reviews, nonfiction, physics, relativity, tutorials

The special and general theories of relativity are hard. It took me years to get somewhat comfortable with some parts of special relativity. General relativity, a theory primarily of gravity, has led to some compelling metaphors such as the rubber-sheet model of space as distorted by mass. But if the math of special relativity is daunting (I find it so), the math of general relativity gets positively pathological. As a consequence, I am always ready to read another treatment of these subjects, for any new insights they can offer.

Professor Chad Orzel's new book How to Teach Relativity to Your Dog is the latest. The author's dog Emma is already well educated, being the foil of his 2009 book How to Teach Physics to Your Dog, which climaxed with quantum mechanics. Emma comes across as being rather better educated than the typical new college freshman, though a bit more enthusiastic, particularly when bacon or bunnies get mentioned.

Throughout the book, Emma asks probing questions as the author tries to explain relativity's concepts in terms a dog can understand. Thus, while Einstein authored thought experiments involving trolleys and lamps and pendulums, Dr. Orzel's examples entail observations of Nero the neighbor cat as he streaks across the yard, or Winthrop the beagle on a day he gets to chase bunnies and Emma doesn't.

One great value of the book is the repeated statement that science has to work the same for all observers. The findings of relativity all flow from this simple principle. I recall being totally flummoxed at first, upon learning that shining a light through the forward port of a fast rocket would not make the light go any faster. In my rocket, I could split part of the beam into an interferometer and measure its velocity as 299,792,458 m/s. The beam out the front window, sent into a similar interferometer by Emma and her master as the rocket approached, would be found to have exactly the same speed! This leads to their clock and my clock running at different rates, to foreshortening of distances as each of us measures the other, and so forth.

All this is explained in early chapters, in a simple enough way that you can get the gist of it, whether you understand the math or not. At its most extreme, near the end of the discussion of general relativity, black holes are discussed. Nero the cat is sent into one by Emma the dog (much to her delight). Each is shining a signaling laser at the other. As Nero falls inward, his laser's light as seen by Emma doesn't change velocity, but its color changes to longer and longer wavelengths. Emma observes Nero seeming to slow down and come to rest at the event horizon.

But from Nero's point of view, he falls inward ever faster, even as Emma's light signal shifts wavelength. He passes the event horizon without noticing it. In fact the only change Nero is going to notice is when tidal effects "spaghettify" him as he approaches the singularity at the black hole's center.

There is no point in going over all that the book covers. It is very readable. The author has somehow captured the personality of a super-smart dog with all of a normal dog's appetites (huge) and enthusiasms (overwhelming). His conversations with Emma are in a great tradition employed by Galileo, Plato and others.

I learned a number of things. For example, I learned a better way to determine relativistic kinetic energy, than the clumsy way I was taught some forty years ago. There is also a brief, but clear explanation why the GPS satellites were set to run 38 microseconds slow, having to do with time dilation caused by both their velocity (slowing them a bit) and their altitude (speeding them up even more).

There is one statement I would modify. In a footnote, the author writes, "The electron is known to be smaller than 10-22 m in radius, one-trillionth the size of an atom. In the Standard Model, it is believed to be a true point, with no measurable size."I would not have used "believed to be", but "mathematically treated as". A minor point, but physics doesn't truck in beliefs.

I find it mildly surprising that Dr. Orzel's earlier book brought out quantum mechanics, before this treatment of relativity. I find quantum mechanics the harder subject. Note to self: get 2009 book, pronto!

Monday, April 16, 2012

Minimizing energy cost on the interplanetary express

kw: analysis, energy, space travel, economics

It is frustrating. Space fiction is filled with 35th Century, or 135th Century folks flitting about space in their interstellar runabouts, going to Mars or Neptune like we might go to Omaha or Yokohama, and catching some kind of hyperspace express to cruise out to Aldebaran or some other locale a few hundred parsecs distant, for a rather modest cost.

The fact is, space travel requires a lot of energy, and energy costs something. At the moment, though, it costs more than it should because a space vehicle has to carry the fuel to make its entire journey, and we take advantage of tricks like using the atmosphere of Earth to slow the return module to parachute speed (or landing speed, for a shuttle-type vehicle, not that any currently exist).

A number of new technologies have been proposed to get a vehicle off the Earth without using any on-board fuel, such as laser propulsion. I don't propose to get into such a discussion here. Rather, given that some kind of remote assist is developed, what is the lowest cost of getting something from point A to point B?

For comparison, we might consider that it costs a few dollars ($20 or less) to ship a kilogram of any legal substance via public carriers or even the US Postal Service, say from western Pennsylvania to Massachusetts, a distance of about 800 km. If I were to personally deliver the package by driving both ways, it would cost more. My car gets 30 miles per gallon, or 48 km/gal, on the highway. That's also about 12.7 km/l. Gas (petrol) cost alone for the 1,600 km trip comes to 33.3 gallons at $4, or $133. But that's partly because the material being moved now weighs a metric ton, not just one kg. On a per kilo basis, the cost is thirteen cents. So the USPS or other carrier is only a few percent efficient, compared to my own costs, if I were carrying lots of packages in my one-ton car (and if I worked for free).

In actuality, the energy costs to the Postal Service or FedEx or whoever, are still a minor portion of total costs. But let's consider that energy-only cost a baseline: $0.133/kg to go 1,600 km, or about 8 cents per 1,000 km. Now let's consider moving a more modest 200 km, but straight up. That'll get us in the neighborhood of the ISS. USPS might charge only $5, but I doubt it. We'll consider achieving orbital velocity separately.

What's the gravitational potential difference between Earth's surface and an altitude of 200 km? Considering the Earth as a point object, which is mathematically valid from its surface outward, potential V = -GM/r. At the surface, Vs = -6.64×10-11×5.97×1024/6.37×106 = -6.255×107 J/kg. Add 200 to the 6,370 km radius of the earth and recalculate, and we get Vorbit = -6.065×107 J/kg. Subtracting these two, we get 1.90×106 J/kg. So what does that amount of energy cost?

In the US, gasoline costs $4 per gallon, and has an energy content of 3.2×107 J/l or 1.2×108 J/gal. The most efficient methods of using gasoline are only 30% efficient, however, so the usable energy cost is about ten cents per megajoule, or 10-7 $/J. Liquid hydrogen can be bought for about $0.40/l, and running the figures I find it costs about 20% more than gasoline for a joule of energy obtained from hydrogen. We can use the 10¢/MJ figure for our calculations. Thus, lifting a kilogram to orbital altitude costs nineteen cents.

Keeping it there requires moving it at orbital velocity, however, which is 7,910 m/s. Ek = ½MV² = 3.13×107 J/kg. This comes to $3.13/kg, more than sixteen times the cost of achieving altitude. That's an important fact about getting around in space: δv (delta vee), or change in velocity, can be a larger factor than the gravitational potential. However, at this point, let's consider that, if we truly could achieve costs as low as $3/kg to get an object into orbit, it would be revolutionary: Attaining orbit presently costs about $10,000/kg. With such a reduced cost we could think about visiting the outer planets.

The major factor going from planet to planet is the gravitational potential relative to the Sun. At Earth, this comes to -8.85×108 J/kg; at Neptune, it is much smaller: -2.95×7 J/kg. Subtracting these yields 8.55×108 J/kg, which costs $88.50/kg. Getting out of Earth's gravity well is a fraction of this (about $6/kg, similar to the cost of going to the Moon). But now there is a time factor to consider. It takes fifteen to twenty years to get to Neptune on a ballistic orbit. In other words, if some kind of energy deposition mechanism gives our one kilogram package an initial velocity of about 40 km/s, it will coast out to Neptune, and have nearly no kinetic energy left, but it might take twenty years or more.

If we increase that to Solar escape velocity, measured from Earth vicinity, or 42 km/s, it'll arrive with velocity comparable to Neptune's orbital velocity of 5.4 km/s. However, it will have required 15-16 years to travel some five billion km. To get there in one year requires a lot more initial velocity, and almost as much δv at the other end to slow down. Initial velocity needs to be of the order of 158 km/s. Kinetic energy comes to 1.25×1010, which costs $1,250. So, take your choice. A decade and a half for $88.50 or a one year delivery time for $1,250, plus another thousand-dollar slowdown fee.

These costs assume we are not accelerating fuel, just the kilogram we want to deliver. Perhaps there will one day be installations, set up by earlier generations (plural, to be sure!), that use something like laser boosting to push a projectile to these velocities, or to push against an incoming package to slow it back down. These costs are just the incremental energy costs for moving a package about. I am ignoring amortization of sunk costs (you know, the odd quadrillion or quintillion dollars to get the laser boosters into Earth orbit—or onto the Moon—, Neptune orbit, and sundry places between).

If getting to Earth orbit drops to some $3/kg, then there is some hope for a 100 kg guy like me to afford an orbital vacation. I'd gladly pay $300 each way for tickets to visit a space station, particularly if a more comfortable one than the ISS is assembled. Of course, I suspect the daily room cost will be more than at your average hotel! Going to Neptune would be more costly. Since the express trip takes a year each way (I don't have thirty years for the slower round trip!), I need some support systems, including plenty of water, air and food. Call it a couple tons. At $1,250/kg to start, $1,200 to stop, and then the same amounts for the return trip, the energy costs alone will come to nearly ten million dollars.

I don't have even one million dollars, nor much prospect of obtaining it. Vacationing in the outer solar system will probably always remain available only to the rich. What about going farther out? Stellar travel has huge time requirements, and to make it practical, the energy has to be balanced against that time.

For a number of reasons, various researchers have settled on a tradeoff velocity of 0.13c, or 39,000 km/s. That'll get you to Proxima Centauri in 33 years and Barnard's Star in 46 years. What is the energy cost? You really need laser boosting, at least at the near end, to make it practical. The relativistic kinetic energy is 7.69×1014 J/kg, at a cost of $76.9 million/kg. How many kg will a vehicle weigh, that can keep a few people alive for decades? 10,000 tons? Assuming that would do it, the energy cost is now $769 billion, or about what each of the "stimulus" packages of 2008 and 2009 cost the US government.

That is the bottom line. Sending people to a star is going to cost trillions. It may be that bombing around the inner solar system will become affordable for many of us, but even visiting the outer solar system will never be within reach to folks like me. Just getting a useful-sized spacecraft up to 0.13c is a project for a nation or a consortium of nations. Getting a kg or two in the form of a Von Neumann self-replicating robot up to such a speed is no cheap undertaking, and sending along fuel enough to allow it to slow down is another huge cost, but much less than the cost of sending people.

This doesn't mean I don't think it will be done. I expect it to take a lot more time, ingenuity, and fortitude. We especially need the planetary will to invest in technologies that enable getting off Earth, into orbit, and off to the planets, at the very least, at greatly reduced incremental cost. In today's dollars, we spent a pretty good chunk of a trillion dollars going to the Moon a few times. With any luck at all, we ought to be able to return to the Moon for one percent of that cost. The Moon is a good base for big lasers to accelerate packages once they are outside the atmosphere; an Earth-based laser facility ought to be able to get them that far. That is step one, and further steps are up to future generations of dreamers.

Friday, April 13, 2012

More on using the moments

kw: musings, time perspective

Three days ago I posted about how some little things I do daily add up over the decades. Of course, my thinking didn't stop there.

Most folks, upon reaching adulthood, have forty to eighty years yet to live. We all have things we must do, and we also do things we like to do. Our habits, weekly or daily, make up the days for us. So in our waking moments, what does a daily minute or a daily hour or quarter hour mean over forty years? If you come of long-lived stock, just double the figures below.

My baseline was the half hour spent each evening brushing teeth and showering, plus the cleanup and dressing, before going to bed. It was easy to note that this uses 1/48th of my total time, or one full year out of each 48. Recalculating for forty years means 40/48, or 304.36 days (304d 9h).

Commuting to and from work used to take me two hours daily, but in the past 16 years, it has been ten minutes each way, which comes to 2/3 of that 1/48 of a day, or 1/72nd of a day, but at a rate of some 240 days per year. In the past 16 years, it adds up to 53d 4h. During the prior ten years, the two daily hours times 240 days added up to 200 days commuting time. Earlier in life I usually had a short commute like I now do, so let's give those 21 years 1/72 of each of 240 days per year, for another 70 days. All totaled up, in 47 years of working life I have spent just over 323 days commuting, or 0.88 year.

On boring days the papers sometimes have an article about how the average American spends six hours daily in front of the TV. Some might, but I suspect for most of us it is less than that. One full hour daily with the TV, over forty years, adds up to twice my shower commitment, or more than 608 days. For the true couch potatoes who spend 6-8 hours daily? It comes to 10-13.3 years of the forty.

How about weekly activities? Some half of Americans spend an hour in church weekly. Ignoring getting ready and commuting, the "pew hours" come to 50 per year (52 for those who attend church while on vacation), or some 2000 hours over forty years. That comes to 83d 8h. Some churches seem to offer more; at least their devotees spend more time there. Say you spend 2 hours on Sunday (one hour in "Sunday school" and one in the "service"), and one hour midweek. That triple time attendance totals 250 days in forty years.

How many do laundry twice weekly? Does it take an hour of your time to wash and dry and sort a load? Maybe half that? That gets you into the same ballpark as attending church an hour weekly. What else do you do weekly; play a half hour of pickup basketball or tennis? That's just over forty days in forty years. How about hitting the gym (aerobics or treadmill) for 30 minutes three times weekly? That is 125 days in 40 years. Not a bad thing to do with just under one percent of your time.

So here are some round figures to think about:
  • One-half hour weekly means about a day per year, or a bit over 40 days in 40 years.
  • One-half hour daily is seven times as much: just over a week per year, or 43 weeks (actually 304 days) in 40 years.
  • Anything you do 8 hours daily, whether sleep or watch TV, is consuming a full third of your time, which comes to 13 years and 122 days in 40 years. Let's just say such a habit finishes eighth grade over a forty year span!
That's all worth a little thought now and then, wouldn't you say?

Thursday, April 12, 2012

Some stellar info

kw: analysis, astronomy, stars, stellar evolution

One item I came across not long ago is a database of 997 of the nearest stars (998 if you include the Sun), all within about 45 light years (~14 parsecs). Of these, 688 Main Sequence stars have been classified and the totals for the five principal classes present are:
K10816 %
M52276 %

The Main Sequence is the stretched-S shaped curve that runs down and across a Hertzsprung-Russell diagram such as those shown in this article. It represents stars that are in the main hydrogen-burning phase of their existence. This "lifetime" ranges from about sixty million years for the hottest O type main sequence stars, through five to ten or more billion years for stars similar to the Sun in the middle of the sequence, to many billions and trillions of years for the smallest H-burning stars, the extreme red dwarfs. (Note: "dwarfs" is correct terminology for small stars. "Dwarves" is reserved for very short people.)

Of the main sequence stars that have been classified, I found 671 that were fully classified, that is, given an alphabetic class (A, F, G, K or M) and a subclass (a number from 0-9). The Sun is presently a G2 star. Leaving out the four A stars, I ran an analysis of each subclass, which can be charted thus:

(Click on this image and the one below for one about twice the size that is easier to read). First, what is Absolute Magnitude? It is the astronomer's measure of a star's brightness. Usually when someone says a star is of first or second magnitude, or whatever, they are speaking of apparent magnitude, the brightness as seen from the surface of the Earth. But if every star could be placed at the same distance, their intrinsic brightnesses could be readily seen. The standard distance for stellar astronomy is ten parsecs, or about 32.62 light years. At this distance, our Sun would be rather dim, at 4.83 magnitudes. On this chart, the bar for G2 is seen to be just under 5 magnitudes tall. The average of all five G2 stars (including Sol) within 45 light years is 4.77.

A parsec means "parallax arc-second". A star one parsec away (none are that close) will appear to move one arc second as compared to much further stars, as the earth moves through three months of the year. (Astronomers actually measure several times over a year, or several years, during which the Earth moves one AU in each of the four directions, giving a set of measurements for the star that can be adjusted for the motion of a single AU Earthside). A star at 10 pc moves 0.1 arc second during the same period.

When the subjective magnitude scale was regularized and made mathematical some 140 years ago, it was decided that five magnitudes would represent a factor of 100 in brightness. A quick glance at the axis of this chart shows that the magnitudes cover a range from about 2.5 to nearly 20, a range of ten million to one: An F0 star is ten million times as bright as an M9 star. Here we can draw a first conclusion about stellar duration. An F0 star weighs about 16 times as much as an M9 star, so divide 16 into 10,000,000, to find that the M9 star will burn hydrogen for 625,000 times as long. It is calculated that the F0 star can burn hydrogen for about 1.2 billion years, so the M9 will last 750 trillion years. This is why we don't know for sure whether M stars become red giants in a way at all similar to F, G, and K stars. None of them has been around long enough to make the transition! The Universe is "only" 13 billion years old.

Since this discussion is proceeding using brightness in terms of "x times" rather than magnitude differences, I offer this companion chart, in which the unit is the Sun's luminosity:

"Luminosity" is the formal term for brightness, including visible and invisible UV and IR light. Though the scale is logarithmic, its numerical labeling is easier to follow. Now we can see that the F stars range down from 10 to about 2 or a little less; the G stars are between 1.7 and just under half the Sun's luminosity; the K stars range from about 0.4 to 0.04, a 10:1 span; and the M stars range downward from there, to essentially zero for an M9.9 star, if any exist, that isn't fusing but a teacupful of hydrogen per year (OK, maybe a ton or two out of the 1025 tons available).

One reason for my interest is the search for planetary systems, particularly planets that might be in the habitable zone where liquid water can exist and persist for long times. The luminosity, color, and "lifetime" of a star are all relevant to the chances it will have a planet on which life can develop, assuming that our own existence means that life can easily develop given appropriate conditions.

Right away, one might say, "Let's look at the small M stars. They last trillions of years. Get life started on one of their planets, and it'll have a long, long time to evolve bug-eyed monsters (BEMs) we might be able to talk to."

M Stars?

Let's consider a star with 0.1 solar mass, probably about an M6. Luminosity is around 0.0002. Lifetime is 10 billion*0.1/0.0002 = 5 trillion years. One complication is that from the time the star begins fusing hydrogen until "turnoff" 5 trillion years later, its brightness increases by a factor of six. A planet that is in the habitable zone at year zero will eventually get cooked. Of course, the next planet out, if there are several, will probably enter the habitable zone about that time, and the changeover is likely to last long enough for some of the residents to relocate outward. They'll likely be able to stay there half a trillion or more years before the heating up jeopardizes their biosphere. But there are two big problems with mid-range and lighter M stars.

Firstly, most M stars are flare stars. The Sun produces an occasional flare that can disrupt our electrical gear and even cause blackouts. The energy hitting Earth increases by a few percent for a day or so, but brings with it a strong magnetic storm that causes havoc. A much smaller star can produce flares just as large, but the baseline—the star's brightness—is a thousand times smaller, meaning the planet has to be 30 times closer, and the flare hits a thousand times harder. Thus the flare can temporarily deposit ten times or more the energy intensity of what the star normally supplies. Lots of that will be UV and X-rays, so you'd need to live deep underground to survive the flare.

Secondly, it takes a planet at least Earth's mass to hold an atmosphere. If it is 30x closer to its star, it will soon become tidally locked, the way the Moon is tidally locked to Earth. Nobody knows what will happen then, but it is likely that all the water will migrate to the dark side and freeze, leaving the planet effectively barren. The way out of this is to have a super-Jupiter that has an Earth-size moon (this kind of system was posited for Pandora in the movie Avatar). The satellite would be tidally locked to its primary, but would rotate with respect to the star.

K Stars?

As it turns out, tidal locking and flaring are much less of a problem beginning near the M-K boundary. A K9 star (isn't it a pity neither of the "dog stars" has this designation!) has a luminosity near 0.05 and a mass near 0.7 of Sol. A mid-class K4 star is more like a dim Sun, with luminosity near 0.15 and mass near 0.9. K stars outnumber G stars three-to-one, being 16% of all main sequence stars. Along with most planetary astronomers, I think the best hunting ground for habitable planets is around K stars. They last 2-5 times as long as the Sun in the H-burning phase, and their brightness evolution is less extreme than an M star's, a range of about 2.5:1 over 20-50 billion years.

G Stars?

Of course, we know that at least one G2 star harbors a liveable planet. But there are a few drawbacks to living with a G star. Its brightness evolution is smaller than that of a K star, but is still significant, about 1.6:1 for the Sun, and 2:1 for a G8 star. And it happens quicker. Astrophysicists expect the Sun's increased brightness to boil off our oceans in another 500 million years. That's all the time we have left to develop interstellar travel, if it is possible at all.

The Earth needed a deep ocean in which life could develop in water deep enough that excess UV would not break apart fragile organic polymers such as proteins or RNA as quickly as they were formed. Life had to be protected from UV until it evolved photosynthesis and began to produce Oxygen, which automatically generated the protective ozone layer. This also reduced the carbon dioxide content of the atmosphere, just as the Sun was heating up (it is 40% hotter than it was four billion years ago).

In fact, the evolution of C4 photosynthesis about 100 million years ago gave us a further reprieve. C4 can drive CO2 levels to 50 ppm, but C3 can drive it only to 1000 ppm. The present level is 380 ppm, up from 280 ppm 150 years ago, but once we run out of oil and coal, it'll go back down. This whole "global warming" phase will end with an ice age long before the Sun gets hot enough to eliminate ice ages. So there are risks associated with G stars also.

Somewhere in this tremendous range of brightness, color, and so forth, there is sure to be a "sweet spot" for the development and nurturing of life. Maybe it really is the range that includes G2 stars, though it is more likely near the G-K boundary. And that is just the range in which we find the largest numbers of stable stars. The Kepler satellite is looking at stars of apparent magnitudes between 9 and 16, in a star cloud that is just distant enough that many of those are F, G, and K stars. The M stars, though they outnumber all the rest, are too faint for Kepler to get stable light curves. Give it time; I am sure a satellite with a more capable telescope will be sent up in another decade or so. Meanwhile, the more we learn, the more we find that there is to learn. We are not at the end of the development of astronomy. We are just getting going good!

Wednesday, April 11, 2012

Is high really low?

kw: book reviews, nonfiction, drug culture, autobiographies

Reading Too Much to Dream: A Psychedelic American Boyhood by Peter Bebergal just made me sad. The author is fortunate that the brain is remarkably robust and adaptable. After spending about a decade in a determined effort to totally burn it out (which he saw as an attempt to achieve enlightenment), he dropped all drugs some twenty years ago and has made a remarkable recovery. In any event, he has become a fluent, compelling writer.

I grew up in the sixties also. I am a few years older than Bebergal. Perhaps I am just lucky: I found by experiment that I am allergic to pot, and it does nothing for me anyway; opium makes me sleep before any mental feelings kick in; I quickly got over an early infatuation with alcohol because I prefer to remain in control of my mind; I tried nothing harder, because I could see how ugly addicts were. From both sides of the divide, I suppose one can say, it takes all types. I am about as straight as they come.

Bebergal was, for a time, about as bent as they come. Luckily, he lived through it. When he had his crash, and his parents were forced to realize the depth of his predicament, it began a recovery process that took a few years. He portrays his parents as pretty much ignorant of what he had been doing. In a sense, he had an anchor in their home, that less fortunate kids didn't have. In spite of spending his adolescence in a wasted condition, he had as a core the habit to return home at the end of the day (whenever it happened to end). As much as anything else, that saved him.

The book's title comes from the song "I had too much to dream last night", recorded by the Electric Prunes. Psychedelia in general was an intimate part of the mix of sex, drugs and rock-n-roll that drove the "me generation" of the "Sixties", which ran until the mid-1970s. Drove, and in part destroyed. Now that some of that generation are running Western governments and industries, perhaps it is no surprise that politics and business are floundering and foundering.

I am beginning to think that there is a physical or chemical difference, or something like that, between folks with left- and right-wing views. Politics in America played host for eight years to what Rush Limbaugh called Bush Derangement Syndrome on the left. Now on the right, we see Obama Derangement Syndrome. Neither is helpful. I spent a few days recently with my father and my three brothers. Two of my brothers are politically liberal. My youngest brother and I are politically conservative. We had a few lively discussions. In a side discussion with my youngest brother, I remarked that it is not surprising he is conservative, because he runs a small business, as I have done in the past. The other two have an entitlement mentality, though not as extreme as I see among many left-leaning members of Congress. Anyway, where this is going: People I know who are right of center did few or no drugs; many (not all) of those who are left of center did a lot, and some still do.

I am glad the author found a way out of addiction, rather than dying of it, which was a fear he had for years. A characteristic of the drug culture is pervasive paranoia. You're a criminal, so of course "they" are out to get you! But the paranoia stays there and becomes part of the trip, particularly a psychedelic trip (LSD; mescaline; 'shrooms), making a bad trip more likely. God is out to get you! I once saw someone, running from some internal demon, run right out a third-floor window.

The chapters contain discussions and digressions into the history of various aspects of new age culture, from Aldous Huxley to Blavatsky to Woodring. They are threads in the whole tapestry that has enmeshed so many addicts. It is hard to say whether Bebergal is advocating greater access to drugs. There is caution in his language when he describes recent medical research into the effects of mind-altering substances. Do these substances provide a shortcut to mental states that meditators, for example, must labor for years to achieve? He is ambiguous.

Married now, with at least one child, the author has stayed clean (his term) for two decades. While he eschews drugs, and sex is now confined to his marital relations, he still clings to the music. "Mental" music is growing up. He writes late in the book about a "concert" of more modern music that appeals to him, and it seems to have no genre, but is somewhere in the "new age" spectrum. He is a product of his own past—no surprise—but has a will and direction he lacked before. Some of that was simply growing up. More was re-learning how to be a free person once he was free of the drugs.

I was, and still am, and outside observer of the drug scene. For me, the book was a window into a world I declined to enter. For some, it will be a beacon they may need, a chronicle of one man's journey in and back out.

Tuesday, April 10, 2012

Measuring the moments

kw: musings, time perspective

I tend to think all kinds of things in the shower. It is one of the very few things during which I can't read. I began to wonder how much of my life this daily ritual is taking up. With no paper or calculator handy, I was stuck doing estimates and rough calculations.

Of course, now that I am out of the shower, I can look up things like the number of seconds in a Tropical year (31,556,925 and change), but for horseback math, I just remember 31.5 million seconds, which equals half a million minutes (plus 5%, or 525 k) or just over 8750 hours (8,766). Similarly the "work month" of four and a third weeks (30.333 days) contains 2,620,800 seconds, which I round to 2.5 million; 43,680 minutes (43.5 k); and 728 hours.

The day I can remember exactly: 86,400 s = 1,440 m = 24 h. The week, being seven times as much, comes to 604,800 s (I remember 600 k), 10,080 m (10 k), and 168 h.

Now, how much time do I spend showering? The whole evening ritual, from brushing teeth to squeegeeing water off the walls takes half an hour. That's 1/48th of my day, and that means that every 48 years I spend a year in the showering ritual. I don't think it has been the same length since birth, so I'll just count my adult life, so far 44 years since I was on my own at age 21. In four more years, I'll have racked up that year! Will I have time to accumulate a second year? Not likely; that'll take until I am 117. I have a reasonable prospect of living 90-95 years, but that's probably the limit.

Eating is quite variable. If I was doing all the cooking, I'd want to calculate that separately, anyway, but I find it takes me only about ten minutes to polish off a meal, unless I am at a buffet restaurant, where I can graze for about an hour. Let's ignore that and consider ordinary meals only: Another half hour daily, and another year accumulated per 48 years lived.

Then there are the big time-consumers, sleep and work. I have worked close to a forty-hour week since the age of 19, but my time off has increased in recent years, so that I currently work only 45 weeks per year, effectively, what with holidays and vacation time: 40x45 = 1,800 hours yearly. In earlier years, it was 40x48 = 1,920. Using 47 for a likely average, I find 1,880 hours. In 46 years, so far, that comes to almost 86,500 hours. Divide that by 8,750 hours in a year, and it is just under ten years (9.9).

Sleep is even harder to calculate, because I would sleep 8-9 hours in my twenties, but I get half that or less now. I can discern three periods in my life. Twelve years of an average 8.5 hours, twenty years of 7 hours, and the past fourteen years I average five hours, including any naps I take. That all adds up (using Gregorian years of 365.2425 days) to just under 109,000 hours. Divide that by 8,750, and we get almost 12.4. That's twelve years on the mattress just since I was 19, plus whatever time I spent sleeping in my childhood.

I spend a quite variable amount of time reading every day. Since it is in spurts (breaks, toilet visits, reading before sleep, before some meals—or after) I really can't pin it down, but it comes to an hour or two daily. That adds up to between 1/24 and 1/12 of my time.

Well, I could dig into more things, like hobbies, but I'd have to have a recorded time budget to get any accuracy. Instead, it got me thinking further: A doctor once said most of us get at least two billion heartbeats before the old ticker wears out. My resting heart rate is near 60 per minute, and two billion seconds comes to 63.4 years. So I am a few millions into my third billion. Three billion seconds is almost exactly 95 years. If I have, say, a half billion heartbeats still in me, and I retire soon, I'll have a "disposable time bank" of some 100,000 waking, usable hours. If I am lucky and live to 95, I'll have more like 200,000 hours available. How well will I spend that time?

Saturday, April 07, 2012

This spring's stony harvest

kw: rocks, rock collecting, jasper, lapidary, photographs

A couple days ago I cleaned up the latest batch of rocks from my tumbler. These 32 stones are all Lavic Jasper that I collected in 2008. Their finished weight ranges from 88 grams down to just under 5 grams. I made closeups of five that I find particularly attractive.

This one looks the most like an agate, in close-up. Lavic Jasper is known and famed for having small fortification agates embedded in the matrix. This piece has a much larger fortification.

Here we have a breccia, that seems to have broken up when in a soft state, then re-cemented. The little bluish spots are some of the agate inclusions mentioned above.

This one has more of the blue agate showing. This feathery matrix is called plume jasper.

Much of the Lavic Jasper is dark brown, which is usually uninteresting. This piece, however, has a banded and swirly appearance that reminds me of the planet Jupiter's cloud bands. The piece is just 1.5x2 cm.

Here we have another piece that has a larger agate section. You can actually see into the stone in the dark vein across the middle.

All this variability shows why Lavic Jasper is my favorite semiprecious gemstone.

Friday, April 06, 2012

The sky says summer is coming

kw: astronomy, constellations, seasons

The early morning sky shows us what will be in the evening sky a season later. This morning, so early in Spring, I saw the Summer Triangle, with its brightest star, Vega, right overhead.

Vega is the bright white star at top center. It is relatively close, at 25 light years, and is an A0 dwarf (type V). If it were as close as Sirius, which is 8 light years away, it would be about 50% brighter than Sirius. As it is, it is the fifth brightest star in the night sky, at visual magnitude (Mv) of 0.03. It is the prototypical zero magnitude star. Its constellation is Lyra.

Altair, in the Eagle constellation (Aquila), is an A7 dwarf, so it is dimmer than Sirius by half, and twice as far away (17 light years), so its Mv is 0.77, making it firmly in the first magnitude range. It is the twelfth brightest star. You'll find it at lower right, the only bright white star in the vicinity.

Deneb, the tail of the Swan (Cygnus), is at center left. It is no dwarf. Rather it is an A2 supergiant at a distance of 3,000 light years. This distance dims it to Mv of 1.24, making it the nineteenth brightest star. Were it as close as red Betelgeuse (430 light years), it would be 4.2 magnitudes brighter than it is, at -3. Only Venus at its brightest (plus Moon and Sun) gets brighter than that. Though it seems a second-rate star, it is intrinsically the brightest star among the brightest 300 stars.

The designations "dwarf" and "giant" are historical in nature, and refer to the luminosity of a star of a particular color. Most stars are yellowish to orange in color, and among them there is a very distinct set of brightness ranges. Those few that are bluish, with few exceptions, are all at least giants, and many are supergiants. The dividing line is stars of color A, which are considered "white" when viewed from the ground. But the atmosphere scatters most of the blue light from stars, so the "yellow" star we call the Sun is actually very white, and an A star such as Sirius (or the three Summer Triangle stars), is distinctly bluish when seen from space.

To delve more into the sizes and colors and luminosities of stars, look here for a good discussion of the Hertzsprung-Russell diagram and how stars' characteristics are shown on it.

Thursday, April 05, 2012

Sharks in the digital gene pool

kw: book reviews, nonfiction, internet, cybercriminals

You may know the old saw: Speak of the devil and he may appear. This is particularly true in cyberspace. The most accomplished hackers, being fond of their reputations, have software agents on the lookout for their names to pop up. Preferring to remain below their radar, I'll leave names out of this review. Interestingly, the author of DarkMarket: Cyberthieves, Cybercops and You, Misha Glenny, names nineteen assorted online criminals, refers to at least sixteen others only by their handle, because he doesn't know their names, and has tentatively determined that two much-revered handles actually belong to consortia.

I came to the book looking for guidance; the and You in the title hinted at personal relevancy. There was none. Perhaps none is possible! On the World Wide Web, it is simply best to keep your wits about you, because it is certain that someone out there is hoping to gain the information needed to plunder your bank account. If you happen to be privy to your company's secrets, there is also someone out there hoping to get access to that. So we see two of the three major arms of online criminality: credit card and bank fraud, and industrial espionage.

The third arm is cyberwarfare. You and I may not be directly engaged in warfare, ever, yet still may suffer its effects: Typically it is carried out via denial-of-service attacks aimed at shutting down a country's or company's online presence. If you do business there, you may find yourself locked out for a time, and perhaps your data will be lost or looted.

The focus of the book is credit fraud, and a major sting carried out by the US FBI, through a web site called DarkMarket. It was a forum for people to "discuss" card fraud, and thus served as a meeting place. Deals were made elsewhere, as the stated aim of the site was to stay (barely) legal. The site was administered mostly by criminals, plus one or two federal agents, unbeknownst to the others. After almost a five-year run, DarkMarket came to an end three years ago.

Carding has several aspects. One is skimming. A small device is added to an ATM, and it reads the magnetic stripe on your ATM card when you swipe it or slip it in. Some have an attachment that reads your PIN as you enter it. The skimmer's "owner" sells the data to someone else, who may use it to clone cards and either raid the card owners' accounts directly, or hire someone else to do so (by visiting ATM after ATM). What is our defense? Get to know how the ATM's you usually use are supposed to look. Be suspicious with a new machine. Most of all, when entering your PIN, hold the other hand above the typing hand, so a nearby camera can't read your fingers. Also keep a sharp eye on a store or restaurant clerk to whom you hand your credit card. Make sure they don't slip the card out of your sight for a moment, to run it through a skimmer under the counter.

Another aspect is stealing a copy of a company's credit card verification database. While this may be done by hacking in, it is usually easier to use phishing, or social engineering. This points up the salient fact about internet security: people are the weak link. Recent incidents of the theft of millions of credit card verification data were cases of someone getting access to a computer with the help, knowing or unknowing, of an insider.

The main substance of the book is a running biography of about three dozen criminals and a number police and government agents around the world. Internet crime is not confined to America, nor to the English speaking world. In fact, some of the biggest players are in Russia, the Ukraine, Turkey, and China. The author singles out Odessa, Ukraine, as a major focus of online criminal activity. But it is simply first (or near first) among many. An innocent-seeming e-mail containing some kind of phishing or malware attack may seem to originate from Toronto, for example, but an expert "cracker tracker" may track it via a random African nation or two, to Singapore, and there find that the origin is still further on, but too obscured to track further.

Near the end, the author discusses what we ought to do with an arrested hacker. He is not discussing the organized criminals—who may employ a hacker for technical skills—, but those who program for the fun of it and for reputation, having little interest in getting money. A few of those currently behind bars are acknowledged as the best technical minds there are. He thinks it a shame to waste their talent. He may have a point, but the practice some have of hiring a hacker as a security agent smacks of putting the hen house in charge of the fox. A brilliant hacker may be useful, but employing one can only be done safely if he (you can count the females on your thumbs) is supervised by someone of equal talent.

The current state of the internet is much like the wild west. A few criminals have been incarcerated, and a few areas have a sheriff watching over things, but almost anything can be got away with, given some planning. I've been told that services such as LifeLock are unhelpful, but I am not sure. At the very least, keeping tabs on your credit report is a must. Employing LifeLock is probably best for those with something worth losing, like a big IRA.

Even though the book didn't have quite what I hoped to find, it is a fascinating read. The author obtained access to several incarcerated criminals and hackers, and to police and agents from a number of agencies. His acknowledgements indicate he taped 200 hours of interviews. That is about par for a history book this size. The hard work was not in gathering information, but in cross checking it, both because various people have various views, and because some just lied. Glenny has done an admirable job ferreting out a coherent picture that is as accurate as we are ever likely to have.

Wednesday, April 04, 2012

Jury Duty

kw: jurisprudence, jury duty

In the county where I now live, the courts are trying to make jury duty as unobtrusive as possible. A couple of weeks ago, I received a summons to report, with the instruction to phone in the prior evening to find out if I actually needed to appear. At work I told my supervisor that I might have jury duty April 4.

I was in Group 3. When I called, I found that Groups 1 through 4 were to appear, while Groups 5 and above were excused. So I called my boss and left a message confirming that I had to spend a day at the court house. While I have received such a summons six times since moving here, I was excused without appearing on three occasions, and on three I went in.

I arrived just as people were being let into the court house through metal detectors, and a couple of minutes later, I was in the Jury Assembly Room, where I spent several hours. In contrast to the other two occasions, the room only filled about a third of the way. Jury Instructions made it clear why. There were no Superior Court cases scheduled today, only cases for the Court of Common Pleas. Thus, none of us would serve on a jury for a felony case, only misdemeanors and traffic violations at the most. That was good news, because a typical felony case is two days or longer, but the minor cases seldom last more than a half day or full day.

We were also told that, in this county, service is considered complete after one day or one trial. In some nearby counties, the instructor said, service is required for a full two-week period, or one trial, so if you keep getting excused from juries (more later), you could spend two weeks sitting in rather uncomfortable chairs, "so think twice before moving to one of those counties!"

There was time for a break after that, and then we sat and sat, waiting for the lunch break, or to be called to a court room for empaneling of any jury. Lunch was expected at 12:30 or 1:00. Just before Noon, a different instructor came in and announced that all the cases for the day had been either settled or excused, and we were free to leave, as soon as we picked up our certificate of service, which is the proof needed to get out of Jury Duty if we are summoned during the coming two years. This time around, that was it!

On the prior occasion that I served, three years ago, I got as far as one court room. About forty of us were taken up, and twelve were chosen at random to sit in the jury box for the attorneys to look over. They use up their peremptory challenges first. They might ask a question, but usually they just decide they don't like someone's looks, and pass a note to the judge, who reads the name and excuses that person. I got excused rather early on, and returned to the Jury Assembly Room. Somebody there kidded me that defense attorneys try to get rid of all the "old, white guys", because they tend to convict at high rates. That day we were all sent home at 3:00.

By contrast to this experience, when I lived in California I had Jury Duty just once. It was to be a two-week stint. On the third day I was empaneled on a jury (I wasn't an old, white guy then; I was 24). We convicted a guy of drunk driving. It was a pretty open and shut case, and deliberations took only an hour. One of the men I sat with today told of a case that was sent to the jury after four hours, but deliberations took three days because a couple of the jurors need a lot of convincing to agree with the other ten.

That's one thing about Jury Duty. You need plenty of negotiating skills. It is amazing how differently people view things, when all twelve see and hear the same evidence and arguments. So the process can be a bit messy, but if you are a criminal or civil defendant, it beats having your fate decided only by a judge, who may not be as impartial as you'd like.

I appreciate the way this county makes it much less of an annoyance, compared to some others. Annoyance or not, I don't mind serving as a juror. If I am ever a defendant, I'll sure be glad a dozen people (more if there are alternates) were willing to hear the case and argue it out, not leaving it to someone's dyspepsia to decide.

Tuesday, April 03, 2012

Make a million-year password

kw: computer security, passwords, analysis

An online bank recently had all its clients upgrade their passwords. In the past, passwords were 4- to 6-digit numbers. Now they have to be an 8- to 10-digit number. Taken at face value, a 10-digit password is not very secure. It has only ten billion possible values, and a special-purpose computer built for cracking encrypted passwords (known as "hashes") can try all ten billion in a tenth of a second. What makes this site more secure is that the password must be entered via a special translation screen that converts it to some kind of text, and it is the text that they check when you are logging in.

Banks and brokerage companies have been slow to attain useful levels of security, but they are getting there. I am rankled by the limit many of them have of ten characters for the length of a password. It is barely adequate, as this chart shows:

Here, based on the number of character strings of each type, we see how long the fastest known machine can try all possible combinations. For example, consider ten characters, limited to upper and lower case letters. There are 5210, or 1.45x1017 possible strings to check. At 1011 per second, the process takes 1.45 million seconds, or 16.7 days.

On average, a password will be found somewhere in the middle of the process. Thus a password such as PlentyHard, or pLeNtYhArD, may take seven or eight or nine days to crack. If you are lucky, it'll take longer; if the cracker is lucky, it might be found almost immediately. Depending on the strategy used by the software, shorter combinations will have been tried already, which might take eight hours, or as much as eighteen. So you see it is necessary to go one step further, either down or to the right, to ensure that at least this level of difficulty is presented to a cyber criminal.

For example, changing a few characters to digits puts you in the next column, such that the full 16.7 days must pass first, before the program tries the next set, which can take three months to crack. But adding a character is much better: PlentyHardy gets into a set that takes 2.4 years to scan, and PlentyHard7 boosts that to 16.5 years, with the 2.4 years as a minimum that has to be got through before the software even tries strings that contain a digit or two.

Here's the rub. Moore's Law for computer power isn't over yet. At present, maximum speed is doubling about every three years. That means that in thirty years, the fastest password cracking machine might be able to check 100 trillion combinations per second. That cuts a 2.4 year task down to under a day. PlentyHard7 just isn't hard enough any more. To be really secure, we need to use passwords that are of thousand-year grade today, so they'll last a while. Even better, let's get into the red territory on the chart above, passwords that will withstand attack for a million years at the 100 billion-per-second rate. They'll still be proof against attack at the kiloyear level in 2040.

Some possibilities:
  • A single-case password with at least 19 characters (e.g. tumblingtumbleweeds)
  • A lower-case-plus-numeric password with 17 characters or more (e.g. dr1ft1nga7ongw1th)
  • A mixed-case password with 16 or more characters (e.g. RoundTHEMountain)
  • A mixed-case-plus-numeric password with at least 15 characters (e.g. Sh3778be8C0m1ng)
While you could save one more character by adding some punctuation, it is hardly necessary. A long, mixed-case password is plenty good enough.

You can see from my examples that I like to use song titles or lyrics and modify them with case shifts and digit substitutions. I am required at work to use at least one punctuation mark, so I might choose Sh377$be$C0m1ng, which can hold off the cracker for billions of years, at present. It is likely to remain secure throughout the 21st Century.

The whole applecart might get upset if quantum computing becomes useful. To crack a password, however, the set of N qubits will have to hold an entire set of hashes of length N. Just getting four values into a qubit has yet to be reliably achieved. Getting more than two qubits to coordinate has also yet to be achieved. Quantum-tronics is quite a bit harder than electronics! But if a quantum computer could set up a string of N qubits with trillions of distinguishable states, a password's hash of size N would be cracked in a single machine cycle (some fraction of a billionth of a second).

If this becomes a reality, we'll be forced to return to banking the old way, with brick-and-mortar branch offices staffed with armies of tellers, handling transactions manually. Even the telephone might be suspect, as programs get better at simulating human interaction. Some things about the good old days are still good.

Monday, April 02, 2012

Space opera the way it ought to be done

kw: book reviews, science fiction, space fiction, space opera

Some nine thousand years from now, will star travel be cheaper than intercontinental travel is today? Will dropping in on an orbital station be of no more consequence than visiting the Walmart in the next town? That is the world of Jack McDevitt's Alex Benedict novels. Firebird is the sixth in a series that began with A Talent for War, first published in 1989.

Alex Benedict, famous for completing an archaeological investigation begun by his uncle Gabriel Benedict, and now his uncle's heir, is best known as a purveyor of antiques. This makes him unpopular with museum curators, who decry the supposed desecration. This fact adds a twist or two to the plot of this novel, in which Alex and his aide Chase Kolpath investigate the disappearance of a famous physicist, and then uncover a quirk in spacetime that may solve a number of other cases of disappearing starships.

The key idea related to the vanishing starships is that black holes, as they move through space, cause a damage track in spacetime that diverts a starship which attempts to enter hyperspace at or near the track. The ship is whipped forward in time by a few years or a few decades, and thereafter tends to appear for a few hours before vanishing for the same period, over and over. The climax of the novel is a rendezvous with one of the missing starships, and the attempt to rescue the passengers from their time warp. For the passengers, three weeks have passed. For "outside space", seven thousand years. The few passengers rescued are truly the oldest "relics" Alex has ever recovered, but they are living and breathing and speaking an archaic French dialect. An epilogue closes the loop on the rest of their fellow passengers.

Another very interesting idea is that of sentient Artificial Intelligences, or AI's. Everyone has at least one of these, but a planet that was carried through a dust cloud has lost all its biological inhabitants, leaving a world full of AI's to fend for themselves. Some become insane, and even pathologically homicidal when humans visit the world after its emergence from the dust cloud. Since pathology is not allowed by their original programming, this starts a debate about their status as possibly sentient and thus worthy of rights and even citizenship. Of course, Alex winds up in the middle of the mess when he and Chase "rescue" an AI from the lost planet, one who has been overseeing a schoolhouse for millennia and is not only bored out of his mind, but fearing retribution from the pathological AI's for his friendly contact with people. In a few thousand years, if humanity survives, computers powerful enough to emulate a human brain in a space no larger than a real brain will certainly become possible. I wonder if they can be "programmed" to be intelligent, or if instead, training will become the norm?

The book is a pleasure to read. A cover blurb on the hardback copy compares McDevitt's work to that of Asimov. As I recall, Asimov's later novels consisted primarily of dialog. McDevitt is also a master of believable dialog. Other than that, the worlds that he builds differ quite a lot from Asimov's, which is all to the good. We need fresh ideas more than a further exploration of older ones. I note in this Wikipedia article that he'll be 77 this year. That is the prime of life for an author.