Discover Magazine | 20 Things You Didn't Know About...

20 Things You Didn't Know About... Math

Fri, 23 Mar 2012 11:20:00 -0400

5 Sometimes the oddest bits of math often turn out to be useful. Quaternions, which can describe the rotation of 3-D objects, were discovered in 1843. They were considered beautiful but useless until 1985, when computer scientists applied them to rendering digital animation.

8 Kurt Gödel, the renowned Austrian logician, made math a lot more confusing in 1931 with his first incompleteness theorem, which said that any sufficiently powerful math system must contain statements that are true but unprovable. Gödel starved himself to death in 1978.

19 Graduate student George Dantzig arrived late to statistics class at Berkeley one day in 1939 and copied two problems off the blackboard. He handed in the answers a few days later, apologizing that they were harder than usual.

20 The “homework” was actually two well-known unproven theorems. Dantzig’s story became famous and inspired a scene from Good Will Hunting...

20 Things You Didn't Know About... Clouds

Mon, 30 Jan 2012 12:35:00 -0500

4 So much for People Power. After reviewing 40 years of cloud-seeding efforts in an area north of Israel, researchers at Tel Aviv University have concluded that seeding doesn’t actually produce additional precipitation (pdf).

12 Highest of them all: 50 miles up, noctilucent, or “night shining,” clouds glow an eerie bluish white. They are invisible by day, but after sunset they catch solar rays shining from far below the horizon.

13 Noctilucent clouds seemed to first appear after the 1883 eruption of Krakatoa and are now a common sight.

18 In 1959 Lt. Col. William Rankin was flying his F-8 fighter jet over a cumulonimbus when the engine failed. He parachuted out and spent the next 30 minutes bounced around inside the storm. Amazingly, he survived.

19 In 2007 German paragliding champion Ewa Wisnierska experienced “cloud suck.” While gliding under a cumulonimbus, she was pulled upward to 32,000 feet. She blacked out due to lack of oxygen but regained consciousness at roughly 23,000 feet.

Image: A lenticular cloud over the Tararua Mountains in the North Island of New Zealand. Courtesy: NASA

20 Things You Didn't Know About... Alcohol

Tue, 10 Jan 2012 12:15:00 -0500

iStockphoto

1. Sobering disclaimer: The family of compounds known as alcohols are all toxins that can kill you, whether instantly, quickly, or gradually.

2. Yet one of them—ethyl alcohol, or ethanol—is a staple of the human diet. Archaeologist Patrick McGovern speculates that fermented beverages were made as early as 100,000 years ago, when people first spread out of Africa.

3. The seeds Johnny Appleseed sold to farmers throughout Ohio and Indiana produced apples that were inedible, but perfect for making hard cider.

4. According to the Drunken Monkey Hypothesis, our zest for alcoholic beverages derives from our distant ancestors’ impulse to seek the ripest, most energy-intensive fruits.

5. Designated driver at the zoo: The Malaysian pen-tailed treeshrew routinely chugs the equivalent of nine glasses of wine a night in naturally fermented nectar, and yet it remains fully functional.

6. For a treeshrew, that is...

20 Things You Didn't Know About... The Periodic Table

Wed, 30 Nov 2011 12:40:00 -0500

1 You may remember the Periodic Table of the Elements as a dreary chart on your classroom wall. If so, you never guessed its real purpose: It’s a giant cheat sheet.

4 To determine atomic weights, scientists had passed currents through various solutions to break them up into their constituent atoms. Responding to a battery’s polarity, the atoms of one element would go thisaway, the atoms of another thataway. The atoms were collected in separate containers and then weighed.

6 Fond of card games, Mendeleyev wrote the weight for each element on a separate index card and sorted them as in solitaire. Elements with similar properties formed a “suit” that he placed in columns ordered by ascending atomic weight.

9 Ehen argon was discovered in 1894, it didn’t fit into any of Mendeleyev’s columns, so he denied its existence—as he did for helium, neon, krypton, xenon, and radon...

Image: Lawrence Berkeley National Lab

20 Things You Didn't Know About... Fire

Fri, 07 Oct 2011 12:55:00 -0400

1 Fire is an event, not a thing. Heating wood or other fuel releases volatile vapors that can rapidly combust with oxygen in the air; the resulting incandescent bloom of gas further heats the fuel, releasing more vapors and perpetuating the cycle.

5 Earth is the only known planet where fire can burn. Everywhere else: Not enough oxygen.

14 Every 52 years, when their calendar completed a cycle, the Aztecs would extinguish every flame in the empire. The high priest would start a new fire on the ripped-open chest of a sacrificial victim. Fires fed from this flame would be distributed throughout the land.

15 Good burn: The 1666 Great Fire of London destroyed 80 percent of the city but also ended an outbreak of bubonic plague that had killed more than 65,000 people the previous year. The fire fried the rats and fleas that carried Yersinia pestis, the plague-causing bacterium.

17 America’s deadliest fire took place April 27, 1865, aboard the steamship Sultana. Among other passengers were 1,500 recently released Union prisoners traveling home up the Mississippi when the boilers exploded. The ship was six times over capacity, which helps explain the death toll of 1,547.

19 Spontaneous combustion is real. Some fuel sources can generate their own heat—by rotting, for instance. Pistachios have so much natural oil and are so prone to heat-generating fat decomposition that the International Maritime Dangerous Goods Code regards them as dangerous.

20 Things You Didn't Know About... Sausage

Wed, 14 Sep 2011 15:35:00 -0400

1 Sausages, a blend of meat or blood protein, fat, and spices, were the first processed food. In The Odyssey Homer unflatteringly compares Odysseus to a fat sausage.

13 Does the thought of haggis make you want to hurl? You can do it for real at haggis-hurling competitions held at the Scottish Highland Games.

17 Too-hot hot dogs: The friction inside a meat grinder running full tilt can create a temperature of 120°F. To keep from melting the fat, some sausage makers dip their grinders in liquid nitrogen...

Image: Sausage. Credit: iStockphoto.com.

20 Things You Didn't Know About... Magnetism

Fri, 12 Aug 2011 12:45:00 -0400

2 When Richard Feynman was asked to explain magnetism, he urged his BBC interviewer to take it on faith (video). After seven minutes of stonewalling, he finally said, “I really can’t do a good job, any job, of explaining magnetic force in terms of something else that you’re more familiar with because I don’t understand it in terms of anything else that you’re more familiar with.”

5 And they don’t actually spin. “Spin” is just a physicist’s term for the little magnetic north and south poles baked into every electron. The orientation of those poles defines the direction of the electron’s (somewhat imaginary) rotation.

6 Why does every electron have those poles? As soon as someone finds out, we’ll get back to you.

14 Ancient mariners navigated by lodestone, naturally occurring magnetic rocks.

15 Where lodestones come from is another mystery of magnetism. Some geologists think they are created when lighting strikes iron-rich rocks.

Image: Jonathon Rosen.

20 Things You Didn't Know About...: 20 Things You Didn’t Know About... Stress

Wed, 27 Jul 2011 12:05:00 -0400

3 Stress can literally break your heart. Takotsubo cardiomyopathy, or “broken heart syndrome,” occurs when the bottom of the heart balloons into the shape of a pot (a tako-tsubo) used in Japan to trap octopus. It’s caused when grief or another extreme stressor makes stress hormones flood the heart.

7 But enough stressing! One way to relax: a career of mild obsolescence. Surveying 200 professions, the site CareerCast.com rated bookbinder the least stressful job of 2011. (Most stressful: firefighter and airline pilot.)

11 Perhaps you should take up violent video games. Researchers at Texas A&M International University gave 103 subjects frustrating tasks, then asked them to play [pdf]. Among subjects with a history of violent gaming, the fake mayhem of Hitman: Blood Money and Call of Duty 2 did a great job of easing stress.

Illustration: Jonathon Rosen

20 Things You Didn't Know About...: 20 Things You Didn’t Know About... Crystals

Tue, 05 Jul 2011 13:00:00 -0400

2 Almost any solid material can crystallize—even DNA. Chemists from New York University, Purdue University, and the Argonne National Laboratory recently created DNA crystals large enough to see with the naked eye. The work could have applications in nanoelectronics and drug development.

3 One thing that is not a crystal: leaded “crystal” glass, like the vases that so many newlyweds dread. (Glass consists of atoms or molecules all in a jumble, not in the well-patterned order that defines a crystal.)

12 The unit of measure for gemstones had humble beginnings. “Carat” comes from the Greek keration, or “carob bean,” which was used as a standard for weighing small quantities. It is equivalent to 200 milligrams, or about 0.007 ounce.

Image: iStockphoto

20 Things You Didn't Know About...: 20 Things You Didn’t Know About... DNA

Mon, 13 Jun 2011 11:40:00 -0400

7 Puny humans: Paris  japonica, a flowering plant native to Japan, has the longest known genome, nearly 150 billion base pairs. That’s 50 times as long as the human genome.

16 Guess who’s in your DNA? At least 8 percent of the human genome originated in viruses, whose genetic code was integrated with ours over roughly 40 million years of primate evolution.

18 Already, forensic specialists can identify criminals from traces of “touch DNA” left in fingerprints at a crime scene.

20 And scientists at the University of Guelph in Ontario showed that DNA from the worm (actually an agave butterfly caterpillar) traditionally placed in bottles of mescal leaches into the liquor. So now we know: You don’t actually have to “swallow the worm” to swallow the worm...

20 Things You Didn't Know About... Spiders

Fri, 13 May 2011 13:15:00 -0400

2 Researchers at the University of São Paulo have developed an improbable way to undo arachnophobia by having patients stare at pictures of “spiderlike” objects—a tripod, a carousel, a person with dreadlocks.

4 The venom of the Brazilian wandering spider, Phoneutria nigriventer, causes painful penile erections that last for many hours.

5 The responsible toxin could yield new treatments for erectile dysfunction.

10 Todd Blackledge at the University of Akron finds that spider silk could be used as synthetic muscle. Adjusting humidity up and down causes the silk to expand and contract with 50 times the punch of the equivalent mass of human muscle.

11 Blackledge envisions spider silk someday being used to operate miniature robotic devices and drug delivery systems.

15 Safe sex: The male nursery web spider (Pisaura mirabilis) will bring a silk-wrapped insect to a female prior to mating so she will eat the gift—instead of him.

16 Safer sex: The funnel-web spider Agelenopsis aperta has a different approach, putting the female into a cataleptic state before mating so she won’t cannibalize him...

20 Things You Didn't Know About... Kissing

Sat, 19 Mar 2011 14:00:00 -0400

1 Only you: Human lips are different from those of all other animals because they are everted, meaning that they purse outward.

6 The Roman military introduced kissing to many non-kissing cultures (after its conquests were over, presumably); later it was European explorers who carried the torch.

Kissing can make men and women more like each other in some ways. In men, a passionate kiss can also promote the hormone oxytocin, which fosters bonding and attachment, according to behavioral neuroscientist Wendy Hill of Lafayette College in Pennsylhovania. And during an open-mouthed kiss, a man passes a bit of testosterone to his partner. Over weeks and months, repeated kissing could enhance a female's libido, making her more receptive to sex.

20 Things You Didn't Know About... Taste

Thu, 10 Feb 2011 15:15:00 -0500

1 Remember the tongue map you learned about in junior high—the one showing taste receptors for sweet flavors on the tip of the tongue, bitter in the back, and sour on the sides? It’s totally wrong.

2 That bogus map came from an English mistranslation of a German research paper...

9 About 15 to 25 percent of all Americans are supertasters, people who have more papillae and taste buds than the rest of us.

10 Too sensitive for their own good: Supertasters turn up their noses at bitter but nutrient-rich veggies such as broccoli and kale. Taste expert Linda Bartoshuk at the University of Florida found this group more likely to have precancerous colon polyps than people with a below-average number of taste buds...

12 Good taste starts early. The flavors of some foods, such as carrots, garlic, and vanilla, wind up not only in mother’s milk but even in amniotic fluid. Julie Mennella at the Monell Chemical Senses Center in Philadelphia has shown that babies prefer foods they first “tasted” in the womb...

20 Things You Didn't Know About... Language

Fri, 21 Jan 2011 13:00:00 -0500

1 The voice box sits lower in the throat in humans than it does in other primates, giving us a uniquely large resonating system. That’s why we alone are able to make the wide range of sounds needed for speech

3 Unfortunately, the placement of our voice box means we can’t breathe and swallow at the same time, as other animals can (choke).

10 Modern technology is making everything smaller, even our words. “Bits of eight” shrank to become byte, “modulate/demodulate” became modem, “picture cell” became pixel, and of course “web log” became blog.

12 Grüss dich, Dunkelheit, mein alter Freund. Three- to five-day-olds born into French-speaking families tend to cry with the rising intonation characteristic of French; babies with German-speaking parents cry with falling tones, much like spoken German. Infants may start learning language in the womb, it seems.

15 And damage to the brain’s superior temporal gyrus can lead to Wernicke’s aphasia. Patients sound as if they are speaking normally, but what they say makes no sense.

18 Really foreign sounds: Spanish Silbo, a whistle language, has only four vowel and four consonant sounds. Audible for miles, it resembles bird calls and is indigenous to—where else?—the Canary Islands.

20 Things You Didn't Know About... The Future

Wed, 12 Jan 2011 15:10:00 -0500

What happens at the end, when we contact the alience, and the Big Answers revealed

20 Things You Didn't Know About... Teeth

Mon, 29 Nov 2010 13:55:00 -0500

11) In 18th-century England, wealthy women might have opted for a tooth transplant, which was briefly popular among the upper classes.

12) No—really, honey, it was the dentist’s fault: Such operations usually failed, and worse, the transplanted teeth often carried syphilis.

19) There have already been some remarkable feats of dental engineering. Last year a Mississippi woman became the first American to undergo osteo-odonto-keratoprosthesis, a treatment for blindness caused by corneal damage. An extracted tooth is sculpted to form a frame for a tiny lens and is then implanted in the eye.

20) How could it be otherwise? The tooth of choice for the procedure: an eyetooth, or canine.

20 Things You Didn't Know About... Nanotechnology

Fri, 29 Oct 2010 14:10:00 -0400

1 Get small. A nanometer is about the width of a strand of DNA; if you design, build, or use functional systems smaller than 100 of these, you’re a nanotechnologist.

2 By that definition, we have been doing nanotech for centuries. For instance, the colors in medieval stained glass windows result from nanocrystals created in the heating and cooling of the glass.

3 Size matters. At the nano scale, materials take on unusual properties. Their color, transparency, and melting point often differ significantly from those of larger clumps of the same stuff...

20 Things You Didn't Know About... Dogs

Wed, 06 Oct 2010 11:10:00 -0400

1 The sultry “dog days of summer” get their name from ancient astronomers who noticed that those days coincide with the period when Sirius, the Dog Star, rises at the same time as the sun.

2 Bad astronomy: Sirius is the brightest star in the sky, but it is just one 10-billionth as bright as the sun and has no effect on our weather.

3 Nerd. Fido will touch his nose to a computer screen if it has a picture of a dog on it but not if it shows a landscape, University of Vienna researchers have found...

20 Things You Didn't Know About... Water

Tue, 10 Aug 2010 12:55:00 -0400

11) Hair on your skin can hold water droplets too. A hairy leg may get sunburned more quickly than a shaved one. 17) Scientists at Oregon State University have identified vast reservoirs of water beneath the ocean floor. In fact, there may be more water under the oceans than in them. 18) Without water, ocean crust would not sink back into the earth’s mantle. There would be no plate tectonics, and our planet would probably be a lot like Venus: hellish and inert.

20 Things You Didn't Know About... Viruses

Tue, 04 May 2010 11:25:00 -0500

Image: Wikimedia commons

1 Viruses are not alive: They do not have cells, they cannot turn food into energy, and without a host they are just inert packets of chemicals.

2 Viruses are not exactly dead, either: They have genes, they reproduce, and they evolve through natural selection.

3 Scientists have been debating this issue since 1892, when Dmitry Ivanovsky, a Russian microbiologist, reported that an infection in tobacco plants spreads via something smaller than a bacterium. That something, now called the tobacco mosaic virus, appears on this page (magnified and colorized).

20 Things You Didn't Know About... Light

Fri, 09 Apr 2010 14:20:00 -0500

The first light in the universe, the light used to push spacecraft, and the light produced by kicking the head of a walrus.

20 Things You Didn't Know About... Digestion

Thu, 07 Jan 2010 12:10:00 -0600

#15: In which painful condition does your body literally start eating yourself from within?

20 Things You Didn't Know About... Computer Hacking

Tue, 05 Jan 2010 11:10:00 -0600

What's the connection between Steve Wozniak, the Pope, and Henry Kissinger? That's right, it's hacking.

20 Things You Didn't Know About... Sugar

Fri, 30 Oct 2009 08:10:00 -0500

Did you know that most of the sugar you eat comes from beets? And that sugar in deep space may be a chemical precursor to life on Earth? Find out these and more sugary facts.

20 Things You Didn't Know About... Hurricanes

Tue, 18 Aug 2009 11:25:00 -0500

A typical hurricane releases some 600 trillion watts of heat energy, equivalent to 200 times the world’s total electrical generating capacity.