Saturday, July 31, 2010
As a student of geochronology, dating and timekeeping is something that I think about a lot.
Right now the scientifically accepted length of a second is defined by the rotation of an atom of Cesium-133 as read by an atomic clock. The reason that particular isotope is used is because all atoms release energy when heated or otherwise excited (often in the form of visual light, a phenomenon called incandescence) and Cesium-133 gives off energy in a very narrow range of frequencies: 9,192,631,770 Hz, which can accurately be detected by a very sensitive piezoelectric crystal oscillator that vibrates in tune with the energy released by an excited Cs-133. Therefore, the internationally accepted length of a second is a 9,192,631,770 rotations of a Cs-133 atom.
(By the way, if you like science fiction with a heaping helping of science like I do, check out the Science of Superman, a book written by a scientist and baby-boomer that tries to explain how that old-school hero's powers work. Though the book is otherwise impeccable, the one real error I can see in the book is that it calls the universally agreed on length of time for a second to be arbitrary, when actually there is a really good reason why that specific number is used: the Cesium atom gives off energy in that narrow, near microwave frequency.)
Amusingly enough, though the definition of a second may be internationally accepted, the spelling of "Cesium" is not: UK scientists spell it "Caesium." This is why I love science, by the way: you can argue about stupid stuff like spelling but not about an immutable physical property of reality.
Anyone that doubts the absolute necessity of defining a supersmall unit of measurement in science like a second should be directed toward the field of particle physics. One of the more successful attempts at testing and proving Einstein's theory of relativity was made with a particle called a Muon, that only exists for several one-millionths of a second before breaking down. The time dilation effects of relativity are invisible at an everyday scale, but even a slight slowdown in the existence and breakdown of a Muon can be registered. Therefore, the effects of going faster can be seen in the breakdown of these tiny particles.
There are a few ways, though, that timekeeping can be kept in the future.
1) Pulsar rotation.
Pulsars are a type of superdense star that are all that remains after a supernova. This star that is too light to collapse and result in a black hole. Because the star still has the superhigh angular momentum left over, it turns superfast, functioning as something like an electric dynamo, with each rotation releasing a colossal amount of electromagnetic radiation that can be detected from earth. The energy given off by the rotation of a pulsar is done with such regularity and precision that it rivals and matches that of atomic clock. Pulsar rotation is so precise that when they were first discovered by astronomers they thought they might be artificial in origin!
One of the shortest rotational periods of a pulsar detected thus far has been 8 seconds. Sure, Pulsars eventually slow down as their angular momentum decreases, but that takes 10-100 million years so there's plenty of time a pulsar can be used reliably.
I firmly believe that it is human destiny to explore the universe, something only temporarily thwarted by shortsighted politicians that oppose our space program. Because pulsars can be detected over colossal distances, they can be detected in space and in space are a lot more meaningful a unit of measurement of time than terrestrial units based on earth's solar system like days, weeks or months. Because it's based on something cosmic and non-humanocentric, it is a system of measurement of time that can be shared with aliens. Yes, don't look at me like that, that's exactly what I said! I'm thinking big here, long term.
Hey, science fiction writers reading this! You can use this one if you want to, free of charge. Just invite me to your book-signing. It'd do wonders for my rep as a prestigious science genius!
2) Hexadecimal Clocks.
There was always something arbitrary about the 24 hour clock, with its 60 minute hours and 60 second minutes. This awkward system comes to us from the Babylonians, who did their mathematics in base-60.
Remember "metric time" from The Simpsons? Sure, we all thought it was a joke, but there was actually a real effort for a short time during the French Revolution to keep time in decimal units of 10, with 100 decimal seconds in 100 decimal minutes, and 10 decimal hours from noon to midnight. This lasted for a grand total of one year, from 1794-1795, when everyone forgot about the whole thing because it was a monster to convert, with a decimal second being .864 of a traditional second. Incidentally, I'm not a materialistic person, but if I was super-rich, the one place I'd indulge myself is in getting an antique post-Revolutionary decimal clock. Well, that and maybe getting William Defoe's Goblin Glider from the first Spider-Man movie...
Hexadecimal notation on the other hand, has advantages that French decimal time doesn't. For one thing it's a 24-hour clock, with the 24 hour day divided into 16 units, which also makes it a cinch to convert, making one hexhour about 90 traditional minutes and a hexminute around 90 seconds. The number is given as a fraction of the passage of a day in hexidecimal notation. Therefore, the moment before midnight is given as ,FFFF and midnight is ,0000. The hexhour can even be broken down into quarter-units too, at the 0,4,8, and C positions when slipped into the second digit.
Though something tells me this might not catch on among non-math majors...
Wednesday, July 28, 2010
Science of the past is something best expressed in the visual arts, mostly because as William Gibson pointed out in his short story, "the Gernsback Continuum," the 1920s and up were the first era where visual artists were involved in defining science and technology. As Gibson put it:
"At the turn of the century, most pencil sharpeners looked like pencil sharpeners, a basic Victorian mechanism. After the 1920s many looked like they were designed in a wind tunnel."
I have the good fortune to live in New York City, which has a ton of buildings that look like Ming the Merciless designed them. This futurism was an art style that, like Film Noir, another American creation, that we didn't even know realized we had created until long after the fact.
Read the Gernsback Continuum here at American Heritage. I'd actually list it as one of the ten most important American short stories, actually. Gibson actually mentioned Frank R. Paul, an artist that was forgotten and then rediscovered two generations later, like Zora Neal Hurston.
And while you're at it, visit this gallery of vintage science illustrations and concepts on Flikr! Some of these are absolutely perfect for rainy days when you have nothing but a computer. I think I've found a new way to vaporize time online, other than Wikipedia, of course.
These designs have to be seen to be believed. Being a Masters student in Geoscience, my mind immediately went to the Victorian era diagram on minerals.
Tuesday, July 27, 2010
The single most extraordinary thing about helium is this: it was discovered on the sun before it was ever discovered on the earth, way back in 1868, when the lines on the emission spectrometer turned on it gave back a result that, at first, solar-observing scientists thought was sodium until they realized what it was they had. In fact, that's where the name for the element comes from: helium, like Helios, Greek god of the Sun.
(Incidentally, whatever happened to Helios, anyway? Come Roman times, Apollo was god of the Sun. The best answer ever came in the Percy Jackson and the Olympians young adult books: poor Helios was "downsized" by the efficient Romans and his job palmed off to an already overworked god.)
As point in fact, there is almost no helium on earth; it is light enough that it evaporated during the planet's formation, and any new helium tends to float off into space. The occasions where helium exists on earth, it's produced by the breakdown of radioactive elements like uranium and thorium and trapped in the earth.
This late discovery - Helium was only discovered on earth in 1895 - is all the more incredible because Helium is the second most common element in the universe. In fact, there is more helium than there is every heavier element put together.
More Helium facts:
Helium is one of the few elements to have no "solid" state, remaining a liquid even up to absolute zero.
Helium (and an isotope of Helium) are one of the few elements to be created by the Big Bang, along with hydrogen, lithium and beryllium. Most of the helium in the universe was created by the big bang, though many more from stellar processes.
The primary use of helium is, believe it or not, in cryogenics and supercold, especially the temperatures needed for powerful magnets. Helium is the second-most chemically inert, nonreactive element and in the column with the Noble Gases, so it makes a great purge gas as it doesn't bond with anything. In fact, there are no known compounds that exist that contain helium. The stability of helium is why it is often created by nuclear processes.
80% of the world's helium comes from refining natural gas in the United States. It was us Americans denying helium as a lifting gas to the Nazis that made them use the more dangerous and flammable gas hydrogen...and led to the Hindenburg disaster.
Why does inhaling helium make your voice higher? Well, here's an involved answer: sound is made by vibrating AIR, not by a vibrating object. Sound, like everything else is a wave, and the faster the number of peaks go by in the wave, the higher the frequency (the more frequent - get it?) and the higher the timbre of a noise. Frequency = Speed/Wavelength, or F = S/W. So, the faster something moves, the greater the number of waves and the "higher" a sound is. Since helium is less dense than air, sound goes through more quickly, and therefore the frequency is higher. Don't worry, helium is inert: the only danger comes from possible oxygen deprivation. There are some gases heavier than air that make vibrations travel more slowly, of course, like sulfur hexaflouride and krypton, but unlike helium these may be dangerous to try. They stay in your lungs as they "sink" in air.
Monday, July 26, 2010
Hypatia is my hero and it's not hard to see why. In the world of Hellenistic Greece, she stood out as a great thinker and teacher, a pagan in a time of mostly Christians, one of history's greatest mathematicians.
Rachel Weisz is going to be playing Hypatia, the single most obvious and appropriate casting choice in the history of Hollywood. I wait with eager anticipation to see "Agora," a movie about the life and challenges of Hypatia and the Library of Alexandria. It's not very often that Hollywood does a movie about a mathematician...the last one I can think of is A Beautiful Mind. It doesn't hurt that Hypatia was supposedly one of the world's most beautiful women, or is at least romanticized as being that way by poets. Carl Freidrich Gauss and Paul Erdos may be great mathematicians, but they definitely don't have much in the way of sex appeal.
I have no idea how it is that I didn't hear about this movie until today. It totally blindsided me, and I usually keep my pulse on movies about math and my hero, Hypatia.
Feast your eyes on the trailer, spuds:
By the way, after several years of text flying at the screen and quick cuts passed as movie trailers, isn't it great to hear an old-fashioned Voice of Doom trailer again? "In a world of conflict and torment...one woman will rise to lead a nation..." It's like the movie trailer was made in 1994!
Sunday, July 25, 2010
Astronomers have more of a sense of humor than any other kind of scientist I know. Take for instance, the "New Horizons" space probe, which in five years will reach Pluto, the first manmade object to study the only truly unexplored region of the solar system, not to mention the Kuiper Belt, the distant and massive asteroid belt beyond Neptune where Pluto and at least several other dwarf planets of its type reside...including several that are much larger. By July, 2015, the probe will reach Pluto.
Not only was the space probe named after a Moody Blues song, the telescope and multispectral imager is named "Ralph," and the ultraviolet image spectrometer is named "Alice." What's even more amazing is that the Dust Counter used by the New Horizons was designed and built by graduate students...who I am colossally envious of to the point of murderous rage.
Words can't express my excitement at this visit to the only unexplored world in the solar system. THE HUMAN ADVENTURE IS ONLY BEGINNING. The only down side is they can't make a flyby past Eris, the recently discovered Trans-Neptunian Object...which is, in many ways, like Pluto's cooler sister. Amazingly, the probe will even leave our Solar System in 2029!
Friday, July 23, 2010
This clip is a bit long, but it is totally worth it to watch in its entirety.
James "The Amazing" Randi, a personal hero of mine, debunks a phony psychic with telekinetic powers. Like Houdini, James Randi is a stage magician and skeptic/rationalist that devotes his efforts to exposing phony psychics by using his expertise as a performer and sleight of hand artist to figure out how so-called "mentalist," "medium" and "telekinetic" feats are done. James Randi also uses experiments to put claims to the test. One of my favorite recent ones is, he debunked the claim that more expensive connection cords improve picture quality.
What's the harm in psychics, after all? After all, they're not encouraging people to not get their children vaccinated, which is negligent and dangerous to the point of evil. They're not making outrageous claims about infinite petroleum under the earth and discouraging development of alternative energy. They're not stunting the understanding of children with fraudulent and untrue non-science like creationism.
The harm that psychics pose is that they blur the line between the real world and the untrue. Whether something makes good showmanship has nothing to do with whether it is true or not, and thus far, no one has been able to demonstrate under controlled conditions any ability to talk to the dead or move objects with their minds. When we go to see a romantic comedy, we enjoy it because we can understand that real-world romance isn't like that.
By the way, the claim that the heated lights together with the polystyrene created static electricity that prevented his mind power from operating? That's such transparent bullshit that it almost isn't worth debunking...but to flex my chemist muscles, here's why that couldn't be true:
Static electricity increases the colder it gets, not the hotter.
Why? Because the colder air is, the less humidity it stores. The more dry the air, the more likely there can be static. The factor that determines the amount of moisture that can be held at a temperature is called "Relative humidity." The RH, the capacity for air to be saturated with water, drops by 50% for every 10 degrees Celsius the temperature rises or drops.
(Incidentally, this tends to be how dehumidifiers work: by cooling air off. Sure, it works, which is more than I can say for some products, but it's hardly a mysterious process and is pretty much a glorified mini air conditioner. Egad, what mysterious process has taken place here? Sometimes, human stupidity is a bottomless pit.)
Monday, July 12, 2010
In a ton of movies, Ouija boards are used to contact evil powers from beyond, who give eerie advice and open the gateway for malevolent spirits to reach our cosmos. Generally, this is extremely unusual performance in a game made by Parker Brothers.
Personally, I think it's all misdirection, and the truly Satanic game is Monopoly. Think about it: have you ever played it with your family and not had it result in arguments, tension, and bad feelings? It's like that game was created by demons to spread anger and discord.
What exactly is, then, the scientific explanation for how Ouija and other spiritualist talking boards work? After all, they seem to result in intelligible data.
The answer is the phenomena called the "ideomotor effect." The ideomotor effect, in a nutshell, is that our bodies can move involuntarily without our being actively aware of it, that at times muscular impulses are made without any volition on our part, without any conscious desires or emotions. Breathing, for example, is a well-known example of an ideomotor impulse.
With a Ouija board, however, movement exists that is consistent with our subconscious impulses. Ideomotor effects have been shown to be extremely vulnerable to suggestion; in fact, a person with strong ideomotor activity can also easily enter a hypnotic state.
In fact, our involuntary muscle actions can be made to behave in response to implanted expectations, according to this guy at QuackWatch. In other words, we ourselves are the source of the motion of a Ouija board.
Ideomotor effects seem supernatural, and are the scientific basis behind not only Ouija boards but also "dowsing" and pendulum-swinging divination.
Here's the thing about everything on this blog: you don't have to take my word for it, look it up. But this time I actually encourage you to try this out for yourself. Wear a blindfold, hold a Ouija board, and have a partner read what you produce. It will produce unintelligible gibberish (or alternatively, like the infinite monkeys on infinite typewriters, you'll produce the greatest novel ever written).
Sunday, July 11, 2010
Now for some good stuff - a topographical map of the planet Mars arranged by altitude. Notice the southern hemisphere is so much higher!
There are some points that go way, way higher than 8km on Mars, but that's because this picture is what the scientist Gauss calls a Geoid - a crucial concept in planetary mapping and geodesy, a sort of surface model/figure of the earth (or other planets) that smooths out extremes by surface gravity. However, the use of 8km as a base shows it goes by earth gravity - which may result in a less useful model.
A geoid is very different from say, a reference ellipsoid, which is a smoothed out, idealized diagram of the earth. These two are used together in the field of Geodesy, which is scientific surveying, how maps are constructed and GPS works. It is the use of mathematics to determine altitudes and points on a map.
If you're like me, you're the sort that gets curious and asks questions, and one for me is this: how exactly is that they KNOW that Mt. Everest is the highest mountain on Earth? The answer is that it wasn't known. Until 1849, it was commonly believed that Kangchenjunga in North India was the highest mountain in the world (today, it is believed to be the 3rd tallest).
Tuesday, July 6, 2010
Science Fiction readers wish they were scientists the same way Tom Clancy readers wish they were Army Rangers and Navy SEALs.
In the early days of science fiction, to have someone that's an honest-to-goodness PhD in science the way most of those early science-obsessed fanboys (and some girls) wished they were, must have been a real treat, something that gave authenticity to the stories. Science Fiction and magazines were seen as a tawdry waste of time, and real-life PhDs in science had better things to do than to give material to Hugo Gernsback and other magazine editors.
Nowadays, a lot of science fiction writers are PhDs: Isaac Asimov, famously, had a PhD in both Physics and Biochemistry (back when it was still called that), Larry Niven has a Masters in Mathematics, and Timothy Zahn was a Physics PhD candidate. Back in the 1930s, though, you took what you could get, and E.E. Smith and his editors were extremely proud of his PhD. Just look at those covers: E.E. Smith...PHD. It's like the PhD is Gladys Knight, and the rest of him are the Pips.
Too bad Smith's degree was in Chemistry, specializing in donut mixes.
Smith had a prose style that could best be described as YELLING, and his technobabble is some of the most astounding I've ever seen (is that why they call it 'Astounding Stories?'), and I watched Star Trek: Voyager. I don't like nitpicking science errors in science fiction, because that's just disruptive to suspension of disbelief, and I'm a good sport when it comes to waiving it in the writer's benefit...but I judge an honest-to-God PhD like donut-boy here by a different standard.
There are some truly headscratching things even in the field of chemistry. Smith's tactic is to browbeat the reader with fifty buck words until they are forced to believe his scientific concepts to make the barrage stop. It's called "suspension of disbelief by intimidation." Or "may the power of bullshit repel thee!"
Take for instance, a real howler in his book Triplanetary. The villains are a weird rhino-squid race named the Nevians that have declared war on the human race. Their power source? Allotropic iron.
(An allotrope is a molecular structure with only one type of element. Depending on how the atoms are arranged, something can have different properties. For example, graphite and diamond are both allotropes that consist of nothing but carbon arranged differently.)
According to Smith, this allotrope of iron is radioactive...so much so that 10% of its mass is switched to energy over time. As it does so, the binding content of the atom is released. This sort-of makes sense, as Iron has more binding in its atoms than any other you care to name. But otherwise...
1) Why would an "iron allotrope" make iron easier to crack apart at the atomic binding level? Iron atoms are iron atoms even if you arrange them differently. That's like saying walnuts are easier to break because you've got them spelling out "I Love You."
2) And this is the big one. Iron is the worst source of radioactive fuel in the entire universe. Literally! Seriously, Smith could have picked an element at random by spinning the periodic table and it would have made a better radioactive fuel source than iron. Iron absorbs nuclear energy, and iron buildup at the core of stars causes supernovas!
Iron is such a good absorber of nuclear reactions that it is actually the heaviest type of element that can be created by stellar processes alone. Only hydrogen existed in the early universe after the Big Bang, where the universe was so hot that fusion reactions could take place. After the Big Bang, five elements existed as a result: Hydrogen, Helium, Lithium and Beryllium, not to mention two isotopes of Helium. As a result of stellar conditions, heavier elements are created up to iron. Helium, in stars larger than our earth, create elements like oxygen, silicon and iron.
Iron has the lowest binding energy of anything, except maybe nickel, and from there elements increase in required energy further away from iron in both directions. Iron will absorb any additional energy placed on it! That is why iron is pretty much useless to any nuclear reaction you care to name - fusion or fission.
Iron is such a good collector of energy, in fact, that the only process that can create heavier elements than iron in the universe are supernovas, which use a high-energy process called beta decay to create the remaining elements (beta decay is a process where beta particles, a proton and neutron - are bounced around from atom to atom).
Dr. Smith, I had two semesters of physics and two semesters of chemistry at the undergraduate university level and I know this.
Smith gave another shocking science error in his novel Skylark of Space. Like the previous error, it was a physics and chemistry mistake that a PhD in Chemistry should know. In Skylark, the crew of an early spaceship land on a planet where salt catalyzes a metal to create super-armor, so the nation that has the table salt in the ship's galley could take over the planet. It reminds me of Matt Groening's "The Nation that Controls Magnesium Controls the Universe."
Now, I can sort-of accept that salt functions as a catalyst, depending on the reaction. Salt turns water into a better electrolyte (conductor of electricity), and oxidation (rust) is an electrochemical process, for example.
But salt being super-rare on an earthlike planet? Of all the materials in the universe to make super-rare on an earthlike world...! Okay, I can accept something like Scandium being super-rare, or Iridium, because those metals are very dense and aren't often found in the crust because they "sink." But salt is made of sodium and chlorine. Sodium and chlorine have two properties that make them super-common that a chemist should know:
1) They are among the ten most common elements in the crust of an earthlike planet, and are so because of their lightness;
2) They instantly combine with each other, covalently, because of their mutual charges. Alkali metals have an single electron, and halogens like chlorine have a free slot for an electron. Zap! They bind together.
There's no scenario where salt wouldn't be common, except for maybe a planet without an ocean or indeed, any water at all, that couldn't function as a solvent to break up earth compounds with both elements.
E.E. Smith may throw a ton of words of greater than five syllables around, and I guess that might be pretty good at suckering the rubes that don't know science. But when it comes to Smith's technobabble...take it with a grain of NaCl.
Friday, July 2, 2010
One of the great disappointments of my childhood was when I used to go to several Astronomy events at Columbia University, and we were invited to see a nebula through a telescope. I looked through the lens and saw a grayish blob! What an unbelievable buzzkill!
You see, I was, thanks to National Geographic’s multiple published pictorials from the Hubble Space Telescope, expecting something brilliant and beautifully colored. I expected something like the purple nebula where Captain Kirk had his final duel with the evil superman Khan. Or the pictures sold on mousepads or museum gift shop posters.
In truth, the brilliant colors of most nebulae are not visible to the normal human eye but are only apparent through astrophotography, a series of techniques to get information about stars that involves long-term exposure, where after 30 minutes or more of holding a single image on a plate, colors and even objects that are typically not visible become that way – astrophotography can usually be done with over the counter film, which makes it a great hobby (for people that aren’t as poor as me, that is). Images color-shift because some types of light wavelengths are more successfully absorbed by film, so it typically becomes necessary to take photographs at different wavelengths and combine them for a color-corrected image.
Actually, what “color” a nebula is typically tells us a lot about them. For instance, the majority of nebula are red, because of the presence of hydrogen, which as a result of ultraviolet light are stripped of electrons and produces the red color. Fun fact – 90% of the entire universe is Hydrogen, with the remaining 9% as Helium and less than 1% as heavier elements.
This goes back to an even more interesting field: emission spectroscopy. Using the light from distant stars, it is possible to determine exactly what it is they’re made of by the light that comes off when something is heated (the fact that things give off light when heated is a property called incandescence). Only photons with a certain energy type are emitted from atoms, giving us their emission spectrum. Therefore, by seeing what colors are absorbed by a specific atom, it is possible to determine what the composition of it is. In this way, the element of Helium was discovered on the sun before it was ever discovered on earth!
There was a great article in “Wired” about the recent photography of a rare blue nebula. Nowhere is it mentioned in the article, however, as to why blue nebulae are so much rarer, however: blue light scatters much more in the deep vacuum of space, so “blue” nebulae are only likely to be visible when something reflects light off of them, like for instance, the stars forming inside of them.