From the people who brought us Kismet…
Meet Nexi, an oddly expressive robot from MIT's Media Lab.
A few words from Nexi
The music of disaster
In 1999, Hurricane Gert formed on the eastern side of the Atlantic and began the long trip to Bermuda. Along the way, it happened to pass over a hydrophone (an underwater microphone) planted half a mile deep in the mid-Atlantic.
And made a little noise.
A hurricane’s intense wind whips the waves into a churning frenzy, and deep below the surface of the ocean the turbulence creates a “rushing sound whose volume is a direct indicator of the storm's destructive power,” according to an MIT press release.
MIT engineering professor Nicholas Makris, in a paper from a forthcoming Geophysical Research Letters, takes data from Gert's cacophonous performance and proposes a new way to gauge the destructive power of an oncoming cyclone.
It's not you, it's physics: The Wallpaper Problem
There you are again, at the 11th hour, wrapping that present.
Off comes the price tag, ‘snip’ goes the scissors, and you peel off a piece of tape. Except that the tape, sensing your hurry, tapers down to a point and leaves with a useless, triangular piece. So you try again, once you find the point that was left on the tape roll. And once again, you find your piece of tape narrowing, narrowing, narrowing.
The same *!@#$ phenomenon happens with wallpaper, too. You can’t just peel it off in a nice, even swath; no, it has to peel away from the wall in those deterministically infuriating triangles.
Well, for what it's worth, it’s not you, it’s physics.
Now, an MIT mathematician and his international team of colleagues officially christen that effect "The Wallpaper Problem.” More importantly, in the March 30 issue of Nature Materials, they try to explainwhy, using a model of the peeling problem that accurately predicts the angle of the triangle.
Continue reading 'It's not you, it's physics: The Wallpaper Problem' >
Can we blame cosmic rays for climate change?
Clouds complicate the measurement of climate change. Last year, for example, a couple of Colorado State students used CloudSat data to show that pollution by aerosols is causing the formation of more of those eerie, high altitude noctilucent clouds. (Said clouds are reportedly encroaching on the lower latitudes…) The increase in cloud cover resulted in an increase of reflected sunlight, which resulted in less solar radiation reaching the surface.
Now, a team of Ukrainian scientists argue that clouds are the only thing that matter when it comes to climate change. Well, almost. Clouds… and solar radiation. Basically, contrary to what almost every other scientist has been saying, they hypothesize that the big picture of climate change has little to do with carbon dioxide. There’s incoming solar radiation, and clouds that either reflect said radiation or reflect it back into space.
Here’s where cosmic rays come in, according to the Ukrainians: they cause an increase in cloud cover by ionizing the atmosphere, which forms aerosols, which leads to more clouds. Thus, cloud cover patterns should follow the same 11 year cycle that is observed in the Sun’s magnetic field, which corresponds the influx of cosmic rays.
Is it time to throw out any inconvenient truths out there?
Continue reading 'Can we blame cosmic rays for climate change?' >
We’ll get you, Enceladus. Just you wait.
Last Wednesday, the Cassini spacecraft whizzed through a giant geyser bursting from the surface of Enceladus, one of Saturn's tiny moons. Cassini’s cameras were poised to take new pictures of Enceladus, and an onboard tool was supposed to analyze the composition of the geyser.
Those Enceladan outbursts, hundreds of miles tall, are curious beasts. Scientists suspect they contain ice and rocky debris, but how such a small and cold body can host these powerful plumes remains a mystery. Is there a watery ocean trapped under the frozen surface? Where does all this energy come from? To add mystery to mystery, last month, we learned that Saturn’s outermost ring actually sops up debris from the geysers.
Well, at least Cassini’s camera worked! (The image above is from NASA/JPL/Space Science Institute.) And so did four of the other devices. The new pictures deliver new details on the polar regions of the moon, which is only about 310 miles in diameter. But we’ll have to wait a few months for an inside look at the geysers.
Continue reading 'We’ll get you, Enceladus. Just you wait.' >
Bang, whimper, or … gamma ray burst from the Death Star?
The astronomy quote of the week comes from Aussie astronomer Peter Tuthill:
"I used to appreciate this spiral just for its beautiful form, but now I can't help a twinge of feeling that it is uncannily like looking down a rifle barrel."
The end could be closer than we thought.
In the March 1st Astrophysical Journal, Tuthill reports on a photogenic binary star system he’s been watching for some time. The dancing duo is a Wolf-Rayet system, which means that one of the stars is dangerously unstable. As in, close to going supernova. The press release calls it a “ticking time bomb.”
For 8 years, Tuthill has believed himself lucky for getting such a nice angle to watch the spiraling star from. Here’s how he describes an image of it (posted on the next page of this post) on his web site:
A sequence of 11 sharp frames show the elegant spiral nebula in the constellation of Sagittarius to be rotating in a circle every 8 months, keeping precise time like a jewel in a cosmic clock. In the image to the left [follow the jump to the next page to see it], we have rotated the camera frame of each of the 11 images so as to follow the motion, and as a result we can stack all our images into a single false-colour composite.
But Tuthill’s stellar view of the star could be bad news for Spaceship Earth.
Continue reading 'Bang, whimper, or … gamma ray burst from the Death Star?' >
Mercurial Meteorites
According to the Meteoritical Society, more than 30,000 meteorities have been identified. (Meteorites are the interstellar rocks that make it through our atmosphere and land on Earth.) Most of them come from the rocky debris (like asteroids and comets) floating through space, but a few dozen are believed to have originated on Mars or the moon.
Or Mercury? (What, can anomalous meteorites only come from places the begin with the letter “M”?)
In a new paper submitted to the journal Meteoritics and Planetary Science, two Canadian astronomers crunch the numbers and find that we should expect Mercury-borne meteorites to strike the Earth at roughly half the rate of those from Mars. In other words, there might already be a few pieces of Mercury here on Earth.
What’s with the number 10^122, anyway?
It’s the latest in a long, long line of mystical, magical numbers. Douglas Adams delivered “42” as the answer to Life, the Universe and Everything. Thanks! And writers like Robert Anton Wilson and Robert Shea gave us the self-fulfilling prophecy of 23. Look for 23, find 23 everywhere, declare “Meaning Found!”
These cosmic associations go way back, at least back to when the Pythagoreans were whipping themselves into a perfect frenzy over the number 10. The best of the numbers, of course, are cosmic in both senses of the word (from Merriam-Webster):
(1) of or relating to the cosmos, the extraterrestrial vastness, or the universe in contrast to the earth alone
(2) of, relating to, or concerned with abstract spiritual or metaphysical ideas.
Scott Funkhouser, A visiting physics prof at The Citadel has given us another: 10^122.
67 new gravitational lenses; no word yet on scratch-resistant coating
This isn’t going to shake up the big questions in cosmology, but it might change the way you think about the night sky. Those stars you see? They may not be where you think they are.
Gravitational lenses operate like funhouse mirrors in deep space. They can magnify, distort and bend the light from distant galaxies, and make them appear in different places than where you would expect. (No word yet on whether they can make galaxies look taller or thinner or shorter or heavier or wavier…) Gravitational lenses, as their name suggests, are usually giant galaxies so massive that they bend spacetime—and thus redirect light or anything else that happens to be traveling close by.
They can be helpful to astronomers: the magnification and redirection of light allows stargazers to see farther into deep space. And thus, farther back in time.
The Cosmological Evolution Survey (COSMOS), led by Nick Scoville at Caltech, recently completed a long, hard look at a patch of the sky roughly equal to the area of 9 full moons (1.6 square degrees). The survey used data from the major league of telescopes: the Hubble, Chandra, Spitzer, and the VLT all contributed images. The researchers found 67 new gravitational lenses.
Continue reading '67 new gravitational lenses; no word yet on scratch-resistant coating' >
A twist on Tornado Alley
We’re still deep in the heart of winter, but tornado season is right around the corner. (You can check out interesting tornado factoids at the NOAA site, here. ) If you live in the Southeast, look out.
A study from the December issue of “Weather and Forecasting,” published by the American Meteorological Society, finds that the deadliest twisters touch down a little closer to Dixie.
Tornado Alley, which stretches from Texas through the Dakotas, still gets the most tornadoes in a given year. But Walker Ashley, a meteorologist at Northern Illinois University, found that the most fatalities occur in a swath further south.
From the press release:
“The country’s most vulnerable region for tornado-related fatalities and killer tornado events basically stretches from Little Rock to Memphis to Tupelo to Birmingham,” Ashley said.
Time waster for mathletes: the music of the primes
Lots of people say they have a favorite number; fewer people would say they have lots and lots of favorite numbers that neatly fit into a favorite number sequence. You know, like primes, Fibonacci numbers, the Extra strong Lucas Pseudoprimes. And even fewer would ever admit to having a favorite number sequence song.
But for those who do...
Neil Sloane, a fellow at AT&T, maintains the Online Encyclopedia of Integer Sequences, which contains 136,699 different sequences. The sequence used as an example on the home page is “Busy Beaver problem: maximal number of steps that an n-state Turing machine can make on an initially blank tape before eventually halting.”
Continue reading 'Time waster for mathletes: the music of the primes' >
Kinematics of the big cat: How high can a tiger jump?
On Christmas Day, a tiger leapt from its enclosure before killing a 17-year-old visitor to the San Francisco Zoo. In a new paper posted on the arXiv, a couple of enterprising Boston-based investigators tackle the basic physics problem implied by the incident:
Can a tiger overcome an obstacle that is thirty-three feet away and twelve and a half feet tall?
It’s a classic two-dimensional projectile motion problem – could a tiger, running at its maximum speed and launching itself at the right angle, clear the fence surrounding the enclosure? (You’d think the problem might have been worked out a little sooner...) In the paper, the authors helpfully connect their equations to the real world, like in this quip:
We begin by first writing down the two-dimensional kinematical equations satisfied by the projectile (tiger).
So can the cat clear the fence?
Continue reading 'Kinematics of the big cat: How high can a tiger jump?' >
Interstellar fugitive?
In the last few years, astronomers have identified 10 “hypervelocity” stars, which race away from the Milky Way at 10 times the speed of normal stars. Nine of these burning bullets are believed to have originated in our own galaxy. What about #10?
Yesterday, astronomers from the Carnegie Institution and Queen’s University Belfast announced that the stellar stranger isn’t from around here. The star is believed to be only about 35 million years old, but it’s about 100 million years away from the center of our galaxy. (They’re calling this the “paradox of youth.”) They estimate that the star is moving at about 1.6 million miles per hour.
How to explain the conflict between its time and position? The stargazers came up with two theories and finally settled on this one: they believe the young star “recently” escaped from the Large Magellanic Cloud (one of our nearest neighboring galaxies).
“Escaped” is probably the wrong word here—“violently expelled” is more like it.
Powered by Rain
Here comes the rain again…
Those April showers may bring something in addition to May flowers. You’ve heard of solar power and wind power, but what about rain power?
It's good news for all the rain dogs out there... French scientists have created a machine that can capture kinetic energy carried by a rain drop as it plummets to the ground. According to their models, the machine can capture about 12 milliwatts from a large raindrop (5 mm diameter) that hits the machine.
From the physorg.com article:
To capture the raindrops’ mechanical energy, the scientists used a PVDF (polyvinylidene fluoride) polymer, a piezoelectric material that converts mechanical energy into electrical energy. When a raindrop impacts the 25-micrometer-thick PVDF, the polymer starts to vibrate. Electrodes embedded in the PVDF are used to recover the electrical charges generated by the vibrations.
The researchers discuss their work in Smart Materials and Structures.
Candidates and science, round two
The presidential campaigns are heating up, and we're still hearing very little about science. Will we? Three weeks ago, Science featured a special section devoted to candidates’ opinions and views on science. Unfortunately, some of those articles are available only to subscribers.
Not so at Physics Today, which is published by the American Institute of Physics. At the web site, you can read about the major candidates and their official positions on topics related to science. Physics Today posed six questions to the major contenders; the topics for the questions included science education, teaching evolution, nuclear weapons, science investment, energy policy and climate change. The answers to the questions are pulled from the candidates’ web sites.
Do you know of other publications tracking the candidates' views on science? Let me know in the "comments" section. Here's a link to the "climate change" section of the New York Times Election Guide.
And if you're not sure which candidate you should throw support, play “Choose Your Candidate” at the Washington Post here.
