The astronauts aboard the International Space Station work every day on all kinds of experiments, from working with robots to preparing for spacewalks. But when they get a break, they often field questions from school children and adults about life in space.
Commander Chris Hadfield recently videotaped himself demonstrating a simple experiment inspired by a common question: If an astronaut cries in space, do their tears fall?
On Earth, of course, it’s gravity that causes tears to roll down the cheek. In a microgravity environment, if an astronaut is sad or gets something in his/her eye, tears will certainly well up, but there will be none of what Smokey Robinson’s tears made on his face.
Hadfield, possibly the most social media-savvy astronaut ever with more than 500,000 Twitter followers, gamely demonstrates that tears do pool under the eye but they make no tracks. Squirting water into his right eye, he rolls his head around, causing the puddle of “tears” to shift back and forth and even roll over the bridge of his nose.
Tears don’t fall, he concludes, so bring a hanky.
Hadfield is no stranger to demonstrating, or discussing, human bodily functions in space. Speaking before the Ontario Space Centre a few years ago, he discussed something that you may have wondered about: going to the bathroom in space.
Kate Rix writes about digital media and education. Visit her website: .
Popular Scienceis the fifth oldest continuously-published monthly magazine—a long way of saying that the magazine has done a fine job of maintaining a niche in a crazily fast-paced industry. Founded in 1872 by science writer Edward Youmans to reach an audience of educated laypeople, Popular Science today combines reviews of the latest gadgets with stories about innovation in design and science. It’s an organized mishmash of news about “the future now,” liberally defined. A recent issue included stories about the military’s use of 3‑D printing and an astrophysicist who questions whether Shakespeare wrote the entire Folio.
With that kind of breadth, the magazine’s archives cover just about everything. And it’s easy to browse through back issues, dating all the way back to 1872, since the magazine teamed up with Google to put a searchable archive on the web. The earliest issues, like this one from February 1920, feature color covers that bring to mind science fiction with a fascination for the imagined future.
One of the cool things about the magazine is its equal attention to new and old technology. Search for “scissors” and you will find this 1964 article about the mechanics of sharpening your own scissors. The archive also offers another search tool that returns results in a visual word frequency grid, which is especially cool if you click the “animate” button. Any social historians out there able to explain why the word “scissor” would appear so often in the mid-20th century?
Interestingly, although the word “internet” dates back to the 1960s, the word didn’t appear in the magazine’s pages until 1989.
Period advertisements are included, which adds to the fun. This issue from September, 1944 includes a house-advertisement on the table of contents page calling for all collectors of back issues to consider surrendering them for the war cause. “There’s a war going on and this is no time for sentiment,” the ad urges. “Grit your teeth and dig out those stacks of back numbers. Then turn them over to your local paper salvage drive!” Enter the archive here.
Most “optical illusions” are not really optical. They have less to do with the way the eyes work than with the way the brain processes the information sent to it from the eyes. For this reason, many scientists prefer to call them visual illusions. So if visual illusions are a trick of the brain, and human brains differ from the brains of other animals, does that mean our visual illusions are uniquely human?
The answer would appear to be no, judging from the cute video below from YouTube. The kitten is falling for the “rotating snakes illusion” developed in 2003 by Japanese psychologist Akiyoshi Kitaoka. The rotating snakes (click here to view in a larger format) are an example of the “peripheral drift illusion,” a phenomenon first described in 1999 by Jocelyn Faubert and Andrew Herbert of the University of Montreal. Cats are very adept at perceiving motion in their peripheral vision. It helps them elude predators and home in on their own prey. But this kitty is thrown for a loop by the illusory motion of the rotating snakes.
The peripheral drift illusion occurs when circularly repeating figures with regular sawtooth patterns of light and dark are viewed in the periphery. You’ll find that if you move your eyes around the various circles, for example going from center point to center point, the circles in your peripheral vision will appear to be moving but the one you are focused on will not. If you stop moving your eyes, a moment later the circles will all appear to stop moving. In the abstract of their 1998 paper (open PDF), Faubert and Herbert write:
Illusory motion is perceived in a dark-to-light direction, but only when one’s gaze is directed to different locations around the stimulus, a point outside the display is fixated and the observer blinks, or when the stimulus is sequentially displayed at different locations whilst the observer fixates one point. We propose that the illusion is produced by the interaction of three factors: (i) introducing transients as a result of eye movements or blinks; (ii) differing latencies in the processing of luminance; and (iii) spatiotemporal integration of the differing luminance signals in the periphery.
This map shows the oldest light in our universe, as detected by the Planck mission. Click on the map for a larger image.
By now the Big Bang theory is widely accepted scientifically. The idea is that the universe began to expand rapidly about 14 billion years ago from a dense, hot state and continues to expand to this day.
One of the most telling fingerprints left behind by the Big Bang is cosmic microwave background radiation. This thermal radiation was thought to be left over from the Big Bang itself. It fills the universe almost completely.
A new map of cosmic radiation questions some of the core concepts of the Big Bang. What if, this precise heat map suggests, the Universe experienced a long, pre-Bang phase? What if the Big Bang wasn’t the first burp of creation after all?
The European Space Agency’s Planck spacecraft measures between infra-red and radio waves, making it possible to see back in time to the first light ever produced.
Cosmologists released the new images of the early universe this week. What surprises them is that Planck detected stronger light signals on one half of the sky than the other and picked up a series of anomalies or “cold spots.” While this doesn’t challenge the Big Bang theory as a whole, it does heighten the mystery around the universe’s birth and development.
The data is still coming in. Like the Human Genome Project, Planck stands to generate double the amount of data it has produced so far.
This full-sky map from the Planck mission shows matter between Earth and the edge of the observable universe. Regions with more mass show up as lighter areas while regions with less mass are darker. The grayed-out areas are where light from our own galaxy was too bright, blocking Planck’s ability to map the more distant matter. Click the map for a larger image.
Some other surprises from the Planck spacecraft data:
• The universe is about 100 million years older and appears to be expanding much slower than previously thought
• There is less dark energy and more matter in the universe than previous research showed.
We’ve written a fair amount on the various facets of Thomas Edison’s career, and somewhat less on his less-famous former employee-become-rival Nikola Tesla (who seems to polarize people in ways Edison doesn’t). Both inventors provoke all kinds of serious speculation, commentary, and debate. But even people having fun with these larger-than-life characters feel the need to pick sides. For example, there’s webcomic The Oatmeal’s “Why Nikola Tesla was the greatest geek who ever lived,” which obviously comes down hard in favor of Tesla. Then there’s Tetsuya Kurosawa Biographical comic Thomas Edison: Genius of the Electric Age, which gives the edge to Edison.
Now, in another showdown between the pioneering geniuses of the electric age, we have Epic Rap Battles of History, Season 2, with Edison and Tesla spitting rhymes to prove who should wear the top inventor’s crown. Previous Epic Rap Battles of History episodes pit Gandhi against Martin Luther King, Obama vs. Romney, and Steve Jobs vs. Bill Gates. They’re all pretty great, but this one goes out to the science history nerds (who have a sense of humor). The lyrics hit the high points of Edison and Tesla’s careers—Edison’s intellectual property theft, endless string of patents, use of direct current, and “stacking riches”; Tesla’s almost religious belief in the power of electricity, disinterest in business, grievances with Edison—and there are plenty of personal insults thrown into the mix.
Whether you’re a partisan of Edison or Tesla, or couldn’t care less either way, no doubt you’ll get a kick out of this. And for an added bonus, check out the “making of” video below.
Before you do anything else, click on the image above and then move little slider (along the bottom of the image) from left to right. Now watch the universe fly by, going from macro to micro. Pretty cool, no? Now read on:
This dynamic infographic comes to us via Number Sleuth, who describes their wonderful creation as follows:
This interactive infographic accurately illustrates the scale of over 100 items within the observable universe ranging from galaxies to insects, nebulae and stars to molecules and atoms. Numerous hot points along the zoom slider allow for direct access to planets, animals, the hydrogen atom and more. As you scroll, a handy dial spins to show you your present magnification level.
While other sites have tried to magnify the universe, no one else has done so with real photographs and 3D renderings.…We hope you have a blast magnifying the universe, know that each time you zoom in a depth, you’re magnifying the universe 10x … and every time you zoom out, the bigger objects are 1/10th of their prior size. If you zoom from the biggest object, The Observable Universe, all the way down to the hydrogen atom’s proton nucleus, you will have zoomed in over 100,000,000,000,000,000,000,000,000,000,000,000,000,000x! Unbelievable isn’t it? Our universe really is immensely massive and surprisingly small.
If you’re familiar with the work of Ray and Charles Eames, this infographic will almost certainly remind you of Powers of Ten, the Eames’ 1977 film. That’s something we’re going to talk about more on Monday. For more info on how to use Magnifying the Universe, please see the instructions here.
Name the three figures, living or dead, with whom you would most like to sit down to dinner. Though perhaps a little tired, the challenge still reveals something worth knowing about the respondent’s personality. If I know the personalities of Open Culture readers at all, I’d wager that more than a few of you would choose to set places at the table for Carl Sagan, Stephen Hawking, and Arthur C. Clarke. Anyone interested in asking the big, existential questions and understanding the science underneath them would have the time of their lives at such a meal, especially if astrophysically inclined. But until a genie grants you this wish, may we offer God, the Universe, and Everything Else?
Presented by Magnus Magnusson, longtime host of the BBC’s Mastermind, this program brings the three together to discuss “the Big Bang theory, God, our existence as well as the possibility of extraterrestrial life.” Hawking, of course, talks through his signature speech synthesizer, and Sagan joins up through a satellite link — beamed through, yes, the very sort of floating miracles of engineering that Clarke wrote about in his novels. With minds like these, you can rest assured that the conversation won’t stray far from what Sagan calls “the fundamental questions,” nor will it come untethered from established human knowledge and float into the realms of wild speculation and wishful thinking. And of course, in such conversations, a sense of humor like Hawking’s — a man who, not expected to reach age thirty, would nevertheless live to see more advancement in human knowledge than anyone else on the broadcast — never goes amiss.
Colin Marshall hosts and produces Notebook on Cities and Culture and writes essays on literature, film, cities, Asia, and aesthetics. He’s at work on a book about Los Angeles, A Los Angeles Primer. Follow him on Twitter at @colinmarshall.
We all need guides for the overwhelming world of the Internet. Digital curators are essential to sifting through the vast and expanding supply of online content because they find the good stuff that’s worth checking out.
When Download the Universe launched a year ago, the digital world gained a smart and discerning curator for the growing number of science ebooks. What a boon for science lovers. Science lends itself uniquely to apps and ebook publishing. And doing what digital publishing does best, a good ebook can bring content to life like no paperback or hardcover can.
Take Harper Collins’ Fragile Earth ($2.99 on iTunes), which came out originally as a glossy coffee table book. Loaded with before and after photos of places on the planet scarred by deforestation and climate change, the book was visually stunning, if pedantic. But when released as an ebook, the whole experience unfolded like a beautiful, heartbreaking origami.
As Download the Universe’s review of the Fragile Earth ebook points out, the app version benefits from digital technology, laying before and after satellite images over one another, rather than side by side, making the experience of seeing them even more profound.
Here’s another one: Color Uncovered (free on iTunes), produced by San Francisco’s Exploratorium Museum, is a rich experience like a museum exhibit itself. Combining text with images and interactive features, the ebook explores how the eye perceives color. The reviewer, New York Times contributor Carl Zimmer, uses his review to discuss what the ebook experience shares with museum exhibits.
In the hands of Download the Universe, it appears that ebook publishing has matured into its own genre, with its own distinct advantages.
Sometimes ebook publishers don’t make good use of available features. This review of Blindsight by journalist Chris Colin notes that the book’s app version, telling the story of a television director who suffers a brain injury, should have included neurological background information in the main story, not as a separate feature.
Download the Universe only reviews ebooks in the digital universe, not spin-offs from traditional print books. They look at Kindle products, self-published pdf manuscripts and apps, and they’ve got top-notch talent reviewing this brave new world on our behalf. The editorial board includes some names you may well recognize, like Sean Carroll (Caltech physicist), Steve Silberman (Wired), Maggie Koerth-Baker (Boing Boing), Annalee Newitz (io9), and David Dobbs (NYTimes, Nat Geo, etc.).
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