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I am not a biologist, nor do I play one on TV. I like to think I have a decent understanding of general science, a working knowledge of logic, and a better than average ability to know when I’m wrong. All three of those failed me when it came to a discussion I had on genetics.

For those of you who don’t know, I run lead on a science podcast called The Wonder of Reality; I do most of the writing and research on the topics and I do a lot of fact checking. Shortly after we released an episode on the eye and how rods and cones work together to give us colour vision, I had a discussion with a friend about genetics and why cones and rods are shaped as they are. When we started talking about mutations and evolution I quickly brought up the case of blue eyes. Blue eyes are a recessive trait and only appear when the mother and father are both blue eyed (or so I thought). Because it was recessive and required both parents to have blue eyes, I was sure that being blue eyed would die out. I was dead wrong.

To understand just how wrong I was, let me first explain how recessive genes actually work. When you were born you got genetic information from your father and mother. In the case of recessive genes, think of it like getting a coin from each of your parents upon your conception: they can either be heads or tails. Recessive genes have to both be heads for you to exhibit that trait, otherwise it’s default tails-land.

via pcadams
“Ah man, just one heads away from having wings!”

But where do your parents get these recessive genes to give to you? Each of your parents have two of them and upon your conception randomly choose which one they’ll each give you. If your parents both have tails then you only get tails, or if they only have heads then you get two heads. It gets tricky when things aren’t so strange forward though. If your parents both have one heads and one tails, there’s a 25% chance you’ll get two heads: there’s a 50% chance you’ll get it from your mother and a 50% chance from your father, giving you a 50% * 50% = 25% chance overall. And this is the first part of where I went wrong.

#1 Even if both parents do not show the recessive trait, their children could

In terms of blue eyes, this means that two brown eyed parents can give birth to a blue eyed child. For this to occur, both parents would need to be “carriers” of the recessive gene and have one heads and one tails in our analogy. If one parent doesn’t have the recessive gene at all, there’s no way for their children to express that trait (because they could only get one copy of the gene from the other parent). However, their grandchildren could express the trait, which leads me to the second fact I got wrong.

#2 Recessive genes do not have a tendency to die out

via Cburnett
“‘Carrier’ is the politically correct term for ‘mover'”

To put this last statement in context, examine the image above. Two “carriers” have a 25% chance of having an unaffected child, a 25% chance of having an affected child, and a 50% chance of producing more carriers. In the first generation half the genes are R (tails) and the other half are r (heads), and looking across the four children we see that half of the genes are R (tails) and half are r (heads). This isn’t just a fluke. If we started with two affected individuals, they would only produce affected individuals conserving the 100% heads through the two generations. (It’s left as an exercise to the reader to prove that this is true in unaffected-unaffected, affected-unaffected, carrier-affected, and carrier-unaffected pairings). To say it directly, the starting ratio of recessive:non-recessive genes should stay the same throughout all generations; being blue eyed will not go away.

What does this mean? It’s estimated that 1/6 of the United States population has blue eyes and a current population of  roughly 317 million people. Assuming that the distribution of genes is completely random, this means 1/6th of the population (53 million) is affected, 65% of the US population are carriers (206 million), and the remaining 58 million are unaffected, meaning that out of the 634 million genes we’re talking about roughly 1/2 (312 million) of them are recessive. But what would happen if we made two more assumptions: that the US was the only country to have this recessive gene (it’s not) and that everyone started randomly mating, thereby redistributing the blue-eyed gene throughout the world. The United States only accounts for ~4.4% of the world population of over 7 billion, so those 312 million recessive genes now pale in comparison to the 14 billion non-recessive genes. Assuming a random distribution again this would leave 3.5 million affected, 307 million as carriers, and roughly 6.7 billion people unaffected. While recessive genes will not disappear, they will manifest less as the recessive gene goes from a high concentration area to a low concentration area, and this was the fact that confused me.

via Wired
“Tear gas is only effective when it’s concentrated, otherwise it’s just air pollution”

These realizations were prompted by an article I read stating that “Blue-Eyed Humans Have A Single, Common Ancestor” as recent as 6,000-10,000 years ago. Could one person have a mutated version of their genes with this recessive trait, and over thousands of years had it spread to millions of people? We know that there are at least 53 million people with blue eyes in the world, meaning that at least 1 in every 132 of these eye-colour genes are “blue”. Around 6,000-10,000 years ago the world population is estimated to be around 5 million, but let’s even low-ball that to 1 million people. At this time the ratio of “blue eye” to “brown eye” genes is 1 to 2 million, and since we early concluded that randomly picking genes shouldn’t change the ratios, there’s no way to go from 1 in 2 million to 1 in 132. Historically there would have to be major wars that killed large numbers of people without the blue eye genes.

Alternately, it might not be completely random which gene is passed on. Over 10,000 years there would have been roughly 400 generations (assuming that a generation happens roughly every 25 years), and our rough calculations from before require that the gene multiply itself 15,000 fold. By itself this would require that the “blue eyed” gene passed itself on 51.2% of the time, a number only slightly higher than the assumed 50%. Given this information, it seems plausible that both human made events and some genetic-bias to blue eyes could have spread the mutation into the millions of people who have it today in the time span of 10,000 years.

Where does that leave our discussion on genetics? Even with there being no known evolutionary advantage for blue eyes, the trait has spread to millions of people and is not expected to die out. The idea that something we take for granted today might only have come about in the last 10,000 years is amazing. It may not be a big thing, but it is proof that we’re still evolving and mutating. And finally, always be ready to admit that you’re wrong and learn something cool in the process.

First off, the reason we make New Year’s resolutions has to do in part with the name for the first month of the year: January. January is named after Janus, the two headed Roman god of beginnings, transitions, gates, doorways, endings, and time. This is why double agent lists are often called Janus lists (for him being two faced) and the month of January is a time of reflection as Janus looks to both the future and the past.

So what are my resolutions? The largest one by far is the podcast I’m working on: The Wonder of Reality. I’m aiming to release a new episode every fortnight, meaning that I have to learn a new topic every two weeks, write a 30 minute presentation on it, and then present it with the rest of the team. It’s going to be intense but I can’t stand the thought of not learning anymore; 2013 will be the year of science and knowledge for me.

Care to join me in my resolution of learning science? You can check out our first episode here and subscribe through all the links on the site. Happy 2013!

Dear Readers,

Over the past six months, my blog has featured two main series: ALOBAM (At Least One Book A Month) and Travis’s Tuesday Tidbit. I’m announcing the end of both, at least in some ways. Before I get into that, let me explain why I started both.

I started the ALOBAM series in June after I started reading science fiction again. I really enjoy reading and I wanted to remember what I read, so I decided to write a summary of the story with my personal take. I also wanted to encourage myself, perhaps artificially, to read more stories as it’s something I missed. ALOBAM solved both these problems. However, I began to realize that my initial format wasn’t ideal as it forced me to split the story into parts with the idea of relaying information as someone read through the book, trying to avoid spoilers as they went. In hindsight, I should have put the entire review inside one spoiler tag and not worried about capturing all my thoughts about the book in the correct order.

Travis’s Tuesday Tidbit started in July when I stumbled across the weird tradition of women trying to “catch” men in leap years. Some of my friends commented on my obscure knowledge, so I decided to start the web series.  This allowed me to recap a lot of the bizarre things I had learnt and practice my writing skills, both of which it did well. I noticed by my fourth article that my passion for the subject matter had waned, mainly because there was no overall topic for the series. I was merely grabbing interesting things I had heard and recounting them. I continued writing every week until October when I took two weeks off while my girlfriend was in town and I presented my Ignite talk. Resuming the weekly tidbits was no longer enjoyable because they didn’t give me a reason to continue; there was nothing to tie them together. I wanted more than that.

Which brings me to what I’m doing now. In November I resumed working on my science podcast with my friends Dana Harrison and Jonathan Fritz. Titled The Wonder of Reality, the podcast covers what science is, what we’re discovering with it, and a lot of what fascinates us with the world around us. We’ll be launching our first episode on January 1st, 2013 and continuing every two weeks from there. In order to do this show, I’m reading a lot of science literature and writing the equivalent of six Tuesday Tidbits every two weeks.

Where does that leave these series? As I’m reading a lot of different publications and articles, I’ll definitely learn new things that I want to remember for later. As a result I’m starting a new, irregular series called “Segmented Science“. Whenever I have something science related I want to remember, I’ll quickly jot down the main points and publish it with links and files. Most likely these posts will later be used in the podcast, but it’s entirely possible that they’ll be thrown away, so think of this series as more of a link farm than anything else.

And just in case you’re a long time reader, you’ll notice that I’ve excluded “Play Smarter” in this discussion. Play Smarter was never a regular series and it’s actually the largest source of traffic to the site despite only having one post. I’m still very excited about it as I love games and analyzing things. Definitely don’t expect something soon, but do expect the series to continue.

Thanks for reading,
Travis

At one point or another, we’ve probably been emailed the following:

Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it deosn’t mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a toatl mses and you can sitll raed it wouthit porbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.

While there wasn’t a published paper on the topic from Cambridge University, Graham Rawlinson from Nottingham University did write his PhD Thesis on “The Significance of Letter Position in Word Recognition” in 1976. He tested a lot of different things such as replacing letters with their mirror images, reversing the letter order of words, reversing the word order of passages, keeping the first two and last two characters fixed while mixing the inner characters, and substituting letters with other ones that may or may not be similar. The results generally showed that it is possible to guess words with incomplete information, and humans are better at guessing the words if only the middle letters have been rearranged. This last part makes a lot of sense if you’ve ever tried to do a Jumble in the newspaper; the whole point is that it’s hard to unscramble words.

How does the trick work? First, note that the text is written in lowercase for the most part. In 1955, Miles Tinker found that reading lowercase text was more legible than all-capital text because of the “characteristic words forms furnished by this type.” Building on this work and scientific studies conducted from 1982 to 1990, Colin Wheildon explains “When a person reads a line of type, the eye recognizes letters by the shapes of their upper halves.” Looking at the shapes of the words, most letters are either switched with letters of the same height (like in “wlohe”) or only offset by one character (as in “ltteer” where tt has been shifted to the left by one character).

The next important point is how much the inside of the words have been jumbled. Two and three letter words cannot be jumbled and four letter words can only have their inside letters swapped. It’s only when we reach five letter words and beyond that we can sufficiently scramble the words to hide their meaning. Here are a few examples from Posit Science:

As soon as the longer words have their letters randomly distributed, it’s very hard to decipher what they say. Assigning one point for each place a letter has moved, the harder scrambled words have scores of 16, 18, and 20 compared to 8, 4, and 8 respectively. This small amount of randomization is easy enough for us to overcome, especially when compared to how the words could have been written.

When reading we also gain context from the sentence as a whole and can infer the meaning of words without knowing what they are. In the third sentence, “The rset can be a toatl mses and you can sitll raed it wouthit porbelm,” 8 of the 15 words are unscrambled giving us ample context. This might be a point we miss as they’re all function words (words that join together the important nouns, verbs, adverbs, and adjectives that give the sentence its substance) which we tend to ignore when reading. Further, while total is rearranged to toatl it retains its overall sound, which is another piece of information we use when reading.

The final issue with the theory is with words that can be rearranged into multiple other words. For example, salt can be rearranged as slat, but these words were avoided in the passage lest the effect be ruined. Clive Tooth has found a wonderful example of this in the following sentence:

“The sprehas had ponits and patles”

There are multiple rearrangements possible here including:

  • The sherpas had pitons and plates.
  • The shapers had points and pleats.
  • The seraphs had pintos and petals.
  • The sphaers had pinots and palets.
  • The sphears had potins and peltas.

In summation, this hoax is similar to writing a paragraph missing that fifth symbol: it’s a pain to concoct but it only slows you down slightly to turn words into conclusions. As a bonus point, grammar is missing in parts such as “According to a research at…” and a word or two don’t unmix rightly such as “rscheearch” to “research” and “iprmoetnt” to “important”. Additional data by a PhD linguist is at this URL: http://www.mrc-cbu.cam.ac.uk/people/matt.davis/Cmabrigde/

Today’s Tangent: Jumble was created by Martin Naydel in 1954 and now appears in more than 600 newspapers daily worldwide. An unintended byproduct was a gameshow in 1994 where four contests would face off to solve jumbles in the fastest time possible. It was one of four game shows created by Wink Martindale and Bill Hilleir for the Family Channel. Jumble only lasted six months, twice as long as the short running Shuffle also created by the duo. None of the game shows were still being produced after 1994.

My Tuesday Tidbits went on an unannounced hiatus for two weeks due to other obligations, such as the talk I did for Ignite 10. I’ll be writing up an article on my experiences leading up to my presentation and on the night, so look for that later this week. – Travis Gerhardt

During wartime lots of things become scarce: metal, meat, sugar, gasoline, and even chocolate. For the United States in World War II, chocolate was sent to the troops leaving those at home looking for something else sweet. It is because of this shortage that they turned towards jelly beans and other confections, helping to broaden the different candies available and ensuring that jelly beans would be around for generations. But there’s a lot more to jelly beans than just a wartime treat, and to tell that tale we need to visit Turkey more than two hundred years ago.

While the exact origins of Turkey Delight are unknown, the modern day version of the sweet was first found in 1776 in Istanbul, Turkey. It was at this time that Bekir Effendi, a confectioner from Anatolia set up a small shop there and started to sell his new confection. Unfortunately information around this event is scarce but we can piece together some things. It seems as though an ancestor of the treat existed back in  1626 as Francis Bacon wrote about similar sweets from Turkey:

They have in Turkey and the East certain confections, which they call servets, which are like to candied conserves, and are made of sugar and lemons, or sugar and citrons, or sugar and violets, and some other flowers; and some mixture of amber for the more delicate persons: and those they dissolve in water, and thereof make their drink, because they are forbidden wine by their law.

Bekir Effendi took this treat and made it softer and covered it in a liberal amount of icing sugar. Legend has it that he presented this sweet to the ruler Abdul Hamid I after he was commissioned to make a new confection; it quickly became a coveted dish and was associated with royalty. Eventually a Briton discovered the delight and brought back crates of it to England, reselling it under the name Turkish Delight. From there it made its way over to the United States and near the end of the 19th century was turned into the jelly bean.

The jelly bean was created by taking the jelly of a Turkish Delight, shaping it into a bean, and coating it with a soft shell of sugar. The coating is added in a method called panning where the centre of the candies are put in a open container that is partly filled with syrup, and then they are rolled allowing the candy to be coated evenly as the shells slowly harden. Since Turkish Delight came in multiple flavours, early jelly beans shared this trait and experienced great success during the penny candy craze of the time.

In the early 1900’s, the penny candy craze subsided in favour of everything chocolate. It wasn’t until World War II that jelly beans and other non-chocolate treats resurged. Then in 1960,  the small Herman Goelitz Candy Company decided to change from primarily producing candy corn to multiple other confections including jelly beans and the United States’ first gummi bears. These jelly beans caught the attention of then Governor of California, Ronald Reagan, who would end up eating them through his two terms in office, famous writing “we can hardly start a meeting or make a decision without passing around the jar of jelly beans.”

In 1976, David Klien had an idea for jelly beans of unusual flavour and top notch quality, and pitched his idea to Herm Rowland, then owner of the Herman Goelitz Candy Company. Using the Goelitz company as a distributor, Klien created the Jelly Belly brand and launched with eight initial flavours including root beer and cream soda, flavours that had never been made into jelly beans before. In 1980, Klein and his business partner sold Jelly Belly and all the associated trademarks to the Herman Goelitz Candy Company for $4.8 million.

Around this same time, Ronald Reagan became President of the United States and with his presidency brought Jelly Belly jelly beans to the Oval Office and on Air Force One. He went further and asked for a blueberry flavoured jelly bean so he could serve red, white, and blue ones at parties he hosted. Then in 1983, Reagan sent Jelly Bellies to the astronauts of the space shuttle Challenger as a surprise. Throughout his eight years as president, he continued to have the jelly beans as a snack, helping to launch the Jelly Belly company into further financial success. Because of this huge influence, a portrait of the former president (shown above) made out of jelly beans hangs in the Jelly Belly visitor centre in Fairfield.

Today’s Tangent: While we may know them as Turkish Delights, the Turks definitely don’t call them that. The original word for these treats were lokum, which now translates from Turkish to English as Turkish Delight. However, not all translations are as simple. In Romanian the word is rahat which is a shorting of the Arabic translation rahat ul-holkum. Interesting, the Romanian rahat took another meaning, roughly translating to shit in English. I’d say that English got the taster of the two translations.

Nightfall is based on a short story that Isaac Asimov wrote in 1941 and which was then expanded into a novel by Isaac Asimov and Robert Silverberg in 1990. It chronicles the experiences of an alien civilization on a planet with six suns, completely illuminating the surface at all times. That is, except for once every 2049 years when the suns disappear and the stars come out. The story is broken into three parts: Twilight (before the darkness), Nightfall (the period of darkness), and Daybreak (everything that happens afterwards). The characters were a good cross-section of different societal views, though the number of non-scientists and females were under represented (yes, there is a correlation between the two even in this alien society). The book forgoes alien terminology such as vorks in place of miles, making it more accessible to the general public. Overall I found that while the story fell into some predictable trappings, it kept me wanting more making its 7.5/10 well earned. A word of caution though: after reading most of the book in one sitting at night, I started to believe that it would not be light again. This is one of the few times I advocate that you take a break at the end of each section.

General Information:

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The first thing to discuss is the Tunnel of Mystery which is  a long enclosure resulting in sensory deprivation for 15 “minutes”. It’s described as completely dark and without sound of movement or any wind. This is similar to what astronauts are put through to test how they cope with solitude, and from our human experiences we find that we start to hallucinate and focus on anything that makes sound, such as our own heartbeat and breathing. Without external stimulation it can be a traumatic experience, which is exactly what happens to most of the aliens who take the ride. However, most people can handle sensory deprivation tanks for more than 15 minutes; it’s likely that the constant sunlight on this alien world caused its inhabitants to have a more extreme reaction. The only thing that bugs me about the description of the ride is how it can accommodate multiple people, yet anyone can exit the ride and lights will come on. Wouldn’t that ruin the experience for everyone else?

Then there’s the excavation of the ruins. It’s true that the desert can obscure great swaths of history, and right now we’re using satellites to try and see the outlines of completely buried pyramids in Egypt. I liked hearing how they found a historical record of a great cataclysmic every 2000 years or so because it was in perfect contrast to the mysticism of the Apostles of Flame who said the same thing. I feel that the authors gave a good depiction of how archaeology is done (how many fires were there?) and especially of how science and religion intermingle without trying to agree.

Which brings us to the discovery of Kalgash Two. When Beenay 25 first realized that there was something wrong with his measurements or theory, he tried to recalculate everything from scratch and then asked someone else to help him with the calculations. This just confirmed that he had done everything correctly, so he then approached his advisor and explained the situation. I thought they might have stumbled onto the theory of relativity, but it turns out there was another massive body in the system on a highly elliptical orbit; an orbit that would have it eclipse the single sun in the sky and plunge half the world into darkness for at least 9 hours.

I was disappointed in the small-world nature of the story. Beenay 25 discovers the new planet and works under Athor 77, the person who originally created the theory of gravitation. Beenay also knows Theremon 762, a highly prolific reporter who’s been assigned a story on the Apostles of Flame. Then again, Beenay also knows Sheerin 501 (the psychologist who investigated the Tunnel of Mystery) as he’s living with Sheerin’s niece and they both are professors at the same university. Finally, Beenay also knows Siferra 89, the leading archaeologist on the Beklimot dig, because they met five years ago at an inner-departmental meeting and became friends. The fact that everyone works for the same university, and that Beenay knows everyone except the Apostles of Flame, seems a little far-fetched  (especially when you consider that all the important work each of them is conducting is related and happens within a year of each other).

Midpoint Discussion:

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Now Nightfall is coming and the situation has changed. Athor has talked to Folimun 66 (the representative for the Apostles of Flame) and Theremon has changed from believing that darkness will come to strongly feeling that the scientists are over-reacting and buying into what the Apostles of Flame are spewing. I liked how the two students (Faro 24 and Yimot 70) tried to replicate the star experience by buying an apartment and poking holes in a sheet. It didn’t make a lot of sense that the Apostles of Flame would attack the observatory after they helped verify their predictions, but for some reason they didn’t want the eclipse to be recorded (more on this later).

Let me quickly touch on the science that’s been presented in the story thus far. Could they have detected a large planet that they can’t see using the theory of graviation? Yes, and it was by observing anomalies in Uranus’ orbit that astronomers hypothesized that Neptune existed and later observed it. Could a planet be invisible to our telescopes due to its colouration? This is less likely but still possible, as it’s hard for us to see planets on a brightly lit day and there are certain wavelengths of light that are harder to see through the atmosphere.

Would they really have been driven mad? By darkness, no, because that’s something that was scary but could be explained and was something they had experience with. In fact, the scientists had a very simple solution for combating that, which was using torches. And where darkness would have been scary, stars would have been terrifying. It’s no longer the darkness they prepared themselves for, but something completely alien and unexpected. (As an aside, I was slightly annoyed at how Sheerin’s explanation of the stars was postponed twice and then didn’t amount to much.)

Final Thoughts:

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Too many important people survived. It’s not surprising that Folimun survived, but having Theremon, Beenay, Sheerin, Siferra, and Yimot make it through means that 75% of the main characters in the observatory survived. This is very surprising given how we hear that there are bodies everywhere, equipment was being wrecked, and fires started all over. Of course, I understand that most of the main characters survived so they could have different experiences in the post-apocalyptic world, and both Yimot and Sheerin die shortly after. But still, 75% survival rate for an onslaught is a little extreme.

Then there’s how Theremon luckily meets up with almost everyone who survives. He randomly bumps into Sheerin and is told that everyone is heading to Amgando Park and that Yimot is dead. This is followed by meeting Siferra after trying to start a fire for the first time (she’s part of the Fire Patrol, so this is only marginally more sensible than the first encounter). Having Siferra and Theremon take the same same road as Beenay is reasonable, but having Beenay at the first checkpoint was very luckily. It made sense that they would be able to only get through a few sections on the highway, but it was convenient that near the end of their authorized trip, they stumble on Folimun to  wrap up the story.

I expected there to be a big twist with Mondior since we never met him but he played a large role in the story. Most of the time, hidden people turn out to be people we already met, and in this case it was simply a cover for Folimun which was an elegant solution. I didn’t like why Folimun attacked the university though; he says he was pretending to be a wild-eyed fanatic and just trying to convince the scientists to leave, but why didn’t he say that? The scientists had confirmed everything he knew and while they distanced themselves from the Apostles of Flame, they were on speaking terms and able to help each other out. Their conflict feels contrived.

My other big issue is Siferra’s character. In the first third of the story she’s pegged as completely uninterested in physical relationships, which is a reasonable characterization for a career-focused woman in a male dominated workforce. However, it still feels stereotypical, especially when she slowly falls for the womanizer Theremon who realizes that he has a softer side and that he loves Siferra. On the positive side, this is at most a subplot so its predictability isn’t much of an issue.

The story was well written and I enjoyed the characters and their interactions. I loved the idea of the stars only coming out every 2049 years and causing mass panic, combined with trying to fight the coming storm. It was a very enjoyable read. And to the people of Kalgash, may there always been a sun in your sky.

Complete this sentence: “I’ll be back in a ___!” While you probably answered “minute”, “second”, or “moment” most people only know the length of the first two. How long is a moment? In medieval times, it was defined to be 1/40th of an hour which is equal to 1.5 minutes or 90 seconds. Interestingly, the moment was further subdivided into twelve equal parts of 7.5 seconds called ounces. The smallest they were willing to go was the atom, a indivisible amount of time that also meant “a twinkling of the eye”. Since there are 47 atoms in an ounce, it’s 15/94th of a second or roughly 160 milliseconds. But how small can we really divide time? To find out, we’ll have to slow things down, way down.

A sixth of a second isn’t much to talk about today when movies have 30 frames a second. In movies and television we often see slow motion sequences, a phenomenon best captured in Time Warp (a science show that documents numerous events with high speed cameras). Today’s high speed cameras can easily shoot 100,000 frames per second, which is 100 faster than the first high speed camera could go. Since Etienne Oehmichen created that first high speed camera (then called an electric stroboscoscope) in 1917, the technology continued to progress until Harold Eugene Edgerton improved the design and started making art, creating the iconic photo above in 1964.

Ultra high speed cameras have practical uses too. Scientists at UCLA are using a 36.7 million FPS camera to detect cancer cells among millions of possible candidates. Still too slow for you? MIT researchers have made a camera that can record light by taking pictures every femtosecond, giving their camera a speed of 10^15 frames per second (one million billion). As of May 2010, the smallest unit of time measured was 12 attoseconds, roughly 80 times shorter than the period between pictures of the camera just mentioned. But if you really want to get the theoretical smallest unit of time, that’s Planck time. Clocking in at 5.39 * 10^-44 seconds, there are roughly 3.1 * 10^25 units of Planck time in an attosecond. Slow still has a long way to go.

Today’s Tangent: A moment is 1.5 minutes, which means it could also be called a sesquiminute. The prefix sesqui- means “one and a half”, leading to one of my favourite words: sesquipedalian. It comes from the Latin sesquipedalis, literally meaning “a foot and a half long”. Today it aptly means “a long word”.

If you ask “What’s the highest point on Earth?” most people will correctly answer “Mt. Everest”. If you ask “What’s the lowest point on Earth?” you’ll get answers of “Death Valley” (the lowest land in North America at 86m below sea level), “The Dead Sea” (the lowest point in Asia at 423m below sea level), or maybe even “Marianas Trench” which is the lowest point on Earth. Located in the Pacific Ocean, it’s almost 11 km at its deepest, a place known as Challenger Deep. First explored in 1960 by humans, there wouldn’t be a return trip by man until 2012.

Just before Christmas in 1872, the HMS Challenger left Portsmouth, England on its four year mission of oceanography. It had nets for retrieving biological samples from different depths, housed six scientists, and travelled 127,000 km over four years. The mission discovered more than 4000 new species of plants and animals, but also discovered the Marianas Trench. Using a sounding line (a line with a weight on the end which is then lowered into the water) they were able to measure the deepest part of the trench. This point was then Challenger Deep after the HMS Challenger.

In 1953, a Swiss physicist named Auguste Piccard constructed and launched the Trieste, named after the Italian city in which it was built. With his son Jacques, the ship made its first dive on August 11. Over the next three years it would complete many more dives in the Mediterranean. These successes lead the United States government to investigate the craft in 1957, and it was recommended as the ideal craft to explore the Challenger Deep. It was bought for $250,000 in 1958 (worth approximately $1.6 million in 2012).

The dive to the Challenger Deep was uneventful. Manned by Lt. Don Walsh and Jacques Piccard, the submersible took nearly five hours to descend on January 23, 1960. During that time, the two occupants had little to do beside check gauges and look at the occasional bioluminescent sea life that swam by. At ~9.5 km they heard a bang which turned out to be the breaking of a secondary Plexiglass window in the entry tube, a non-fatal event. Once they reached the bottom they only stayed there for 20 minutes before returning up by dropping their ballast; the return trip only took 3 hours and fifteen minutes.

In March of 2012, James Cameron descended to the bottom of the Challenger Deep in a one-manned submersible. His descent took 2.5 hours and he spent 3 hours at the bottom, only half of his scheduled 6 hours which were cut short due to a hydraulic fluid leak. He brought multiple 3D cameras with him and recorded footage of his journey, and the team is eager to work out the kinks and try again. With only three people even reaching the bottom, Challenger Deep is one of the most remote places on the planet.

Today’s Tangent: As stated above, Mount Everest is the highest point in the world. But the highest point does not the tallest mountain make. Mount Everest is anywhere from 3.6 to 4.6 km high (3.6 on the south face and 4.6 on the north face) and is only the highest point because it’s in a mountainous region, raising its base more than 4 km. For the tallest mountain, look to Mauna Kea and Mauna Loa in Hawaii, both of which are 10.2 km tall though partly underwater. The tallest mountain on land is Mount McKinley in Alaska at 5.3 to 5.9 km tall.

Time has always been a fascination for humans. Just look at our sayings: we can save time, waste time, kill time, take our time, be pressed for time, run out of time, let time slip through our fingers, stall for time, be just in time, spend time, make time, have free time, be on time, have a tough time, watch time fly, watch time crawl, have a great time, be out of time, or even take time off. But despite all of this and our understanding of the theories of relativity, we have not yet been able to travel through time. That is, unless you discount the ten days that were skipped from October 4 to October 15 in 1582.

Let’s start with a flashback to 46 BC when Julius Caesar introduced the Julian Calendar. It was a simple design, consisting of 365 days with a 366th day being inserted every four years. This made a year 365.25 days on average, which roughly corresponded to what it actually was and it provided a simple rule to correct for seasonal drift. Unfortunately it wasn’t easy converting from the existing calendar to the new one, and it resulted in the “Year of Confusion” in 46 BC – the year had 445 days.

Jumping ahead to 325 AD, the first official council of the Christian Church meet in Nicaea to discuss Easter. The date for Easter is based on a complicated formula (you can see the current formula here) based on the vernal equinox (the “first day of spring”) and the cycle of the moon. In order for Easter to fall at roughly the same time each year, they set March 21st to be the vernal equinox. Unfortunately, the Julian calendar’s estimate of a year as 365.25 days was a bit too much, resulting in a drift of one day every 130 years.

Fast forward to 1582 and 1257 years have passed since March 21st was made the vernal equinox. By this point, the calendar was 10 days off from what it should be and so Pope Gregorius XIII (with the help of astronomer Christopher Clavius) determined that they would have to skip 10 days to get things back on track. Thus everyone in Venice, Spain, Portugal, France, the Dutch Republic, and Southern Netherlands made the transistion in 1582, while other countries wouldn’t follow until decades later, with Russia finally converting in 1918. If the change to the Julian calendar could be called the Year of Confusion, this is surely the Centuries of Confusion as the date difference only got worse as the years passed, reaching 13 days by the time Russia switched. Until everyone used the new Gregorian calendar, countries and their citizens needed to know how to switch between the two calendars.

Even in those countries that changed right away, it wasn’t a smooth transition. There was a lot of outcry from the public about religious ceremonies during those times. Since 10 days had been skipped, what happened to those celebrations? And would celebrating them on the new calendar days appease their deities as well as before the change? Even worse, Pope Gregorius XIII knew that his new calendar had to work better than the old one, so he corrected how leap years worked:

  • They would happen every 4 years
  • Every 100 years their wouldn’t be a leap year
  • Every 400 years there would

Thus over four hundred years there would only be 97 leap years instead of 100, leading to an average year of 365.2425 days. The other change involved the equinoxes and solstices no longer being fixed to a specific date. As seen in the image above from Wikipedia, the summer solstice (the “first day of summer”) moves around by day over hundreds of years.

Of course this isn’t the end of the story. As the millennia wear on, addition corrections will need to be made. Earth’s rotation will slow from the Moon’s pull, Jupiter will slowly precess Earth’s axis, and changes on the surface of our planet alter its mass distribution and thus its rotation speed. In time, our descendants might once again leap into the future.

Today’s Tangent: You’ve heard of leap years, but have you heard of leap seconds? Due to the small changes in Earth’s rotation mentioned above, days aren’t exactly 24 hours. Over years these small differences add up from millseconds to seconds, and a leap second must be added, creating the time 23:59:60. Since the creation of the idea in 1972, 25 leap seconds have been added, most recently on June 30, 2012. Unfortunately, due to changes on Earth itself from earthquakes and other events, it’s impossible to know when the next leap second will need to be scheduled.

Nemesis by Isaac Asimov was an enjoyable tale about how a small self-contained settlement leaves the Solar System to orbit another star. The story has two timelines that alternate, one in the present and another from fifteen years ago that slowly approaches the present. The intersection is well done and I enjoyed the story for the most part. However, there are a few scientific things that bugged me, so inside of doing a review I’m going to deal with the science concepts discussed in the book from a present day perspective.

General Information:

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The biggest issue I had with the story was the name. As soon as I saw the title was Nemesis, I immediately jumped to the Nemisis theory which posits that there exists a rogue star which enters into our solar system at a set interval. Knowing that it’s rumoured to take millions of years per orbit, that it would have to be more massive than Jupiter to sustain nuclear fusion (and thus make it a star), and that the closest star is roughly 4.3 light years away, it all seemed rather unlikely. Why? First, Nemisis would have to be on a highly elliptical orbit, passing inside our solar system at its closest point yet be very far away otherwise to maintain its million year orbit. Next, it would have to stay gravitationally bound in order to have this periodic orbit. Third, it would need to go unnoticed to the point that present day astronomy has not detected it.

Asimov drops almost all of these problems by the wayside. It’s named Nemesis because it’s found to be closer than Alpha Centauri, not because it’s going to destroy Earth. It’s discovery still bothers me though. This is a star that’s two light years away from us, yet no one has measured it’s parallax before. The first successful stellar parallax measurement was in 1838 of a star more than 10 light years away. Granted, the star is hidden behind a dust cloud which dims the already dim star further which might make it so that people overlooked it, but it’s so close that people would have had to see it’s annual parallax movement. Did they mistake it for an asteroid? Maybe, but then they would have seen it return to its original position at the end of the year, removing that possibility. No matter how you look at it, we should have seen it before now.

I  have to praise Asimov for some things though. Nemesis does not orbit our Sun but instead is haphazardly moving through the Milky Way and will just happen to intersect our solar system this one time. In making the name and purpose of Nemesis work he’s done two things right, though I still dislike that no one discovered the star for so long.

Midpoint Discussion:

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What about the solar system that Asimov describes? As we’ve studied solar systems besides our own, we continue to find more and more with large gas giants orbiting closer than Earth orbits the Sun, which is in sharp contrast to our own solar system. This is partly due to selection bias (it’s easier to detect large planets than small ones), but it still shows a predominance for large, close planets due to the sheer number of them.

Further, moons will become tidally locked with planets, just like our moon is tidally locked with Earth, and planets will become tidally locked with their stars, just like Mercury is tidally locked with the Sun. The orbital period of roughly one Earth day is also in line with our solar system, as Jupiter has at least four moons that orbit it in less than a day. However, Jupiter’s largest moon is only 40% as wide as Earth, unlike Erythro which is larger than Earth. Besides this last point, everything else has a president and seems plausible.

The last point to touch on is how habitable the planet would be. Earth varies by roughly 5 million km over its entire orbit, and the larger temperature variation we feel is not from distance but from our axial tilt which cause the seasons. Nemesis is dimmer than the Sun so Erythro cannot vary as much in it’s orbit, but because it has no axial tilt then this isn’t much of an issue. It seems quite plausible that Erythro would be habitable and stay that way.

Final Thoughts:

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This brings us to hyper-assistance. First off, I have no great issue with exceeding the speed of light. There have been a lot of discussions over the years as to how it might be possible, and there are some theories that look similar to Star Trek’s Warp Drive. I also like how the first version of hyper-assistance requires that your overall trip not exceed the speed of light while the final version allows you to forgo this restriction.

Hyperspace is a little stranger. It’s quite possible that hyperspace has different laws than normal space and that they didn’t know of these rules when they first set to work. Perhaps even the first tests didn’t show them, and there was no obvious proof until the first human flight. But then why did Chao-Li Wu find something that everyone else missed for over a year? It’s just like how Einstein discovered relativity because he was annoyed by a lack of explanation of various phenomena; Wu may also have been bothered by the lack of a path in hyperspace, causing him to develop his own theory that better explained all of hyperspace theory, just like Einstein better described gravity.

Now should hyperspace have negative gravity? Maybe. Here I think Asimov is drawing on antimatter. One idea behind antimatter is that it’s negative energy travelling backwards in time, like matter is positive energy travelling forwards in time. In order to make antimatter work we have to flip two things to negative, and the same idea is applied to hyperspace.

And that’s it! Overall the science is within reasonable bounds, though the time it took to discover Nemesis still bothers me. Now that I’ve gotten all that off my chest, I can go read something else.