Thursday, April 30, 2015

Mercury Spacecraft Crashes with the Energy of Two Thousand Falling Trees

For the past eight years NASA's MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) spacecraft has been sending back gigabytes of images and data from the Sun's closest companion, Mercury. Today this will come to a fiery end when the fuel-depleted spacecraft crashes into the surface of Mercury in a planned end to the highly-successful mission.

Craters on Mercury colored by the type of material. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
The resulting crater, estimated to be about 50 feet wide, will join the countless other craters that MESSENGER has imaged in great detail. The data from MESSENGER has revealed many surprises over the years including ice in the shadowy craters at Mercury's south pole, a misaligned magnetic field compared to the spin axis of Mercury, an excess of volatile elements like potassium and sulfur that shed light on how Mercury may have formed, and unusual "hollows" or depressions etched into the surface that haven't been seen on any other planet.

An enhanced-color view of Mercury. Credit: Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
To get a sense of scale of MESSENGER's impact, let's compare it to a falling tree (as an Oregonian from a logging town, this was the first analogy that came to mind).

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Wednesday, April 29, 2015

The Best Short Quantum Films You'll See Today

This award winning film lets you experience what happens when solar wind slams into Earth's magnetosphere. The results are downright spooky.



This is the short film 20hz, based on data from the CARISMA radio telescope array during a geo-magnetic storm in Earth's upper atmosphere. The researchers converted the radio signals picked up by the telescope array into audible sounds, which the filmmakers then turned into a visual representation.

It garnered first place in the 2014 Quantum Shorts film contest put on by the Center for Quantum Technologies at the National University of Singapore. Since 2012, the center has invited aspiring filmmakers to put together short films based on or inspired by the weirdness of quantum phenomena.

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Podcast: On Vacation this Week

The PhysicsCentral podcast is taking a much needed vacation. We'll return next week, but to tide you over until then, we're rerunning our post from September highlighting the 2014 winners of the annual Ig Nobel Prizes.



Ig Nobel founder and master of ceremonies, Marc Abrahams holds up this year's prize. The theme of the year was "Food."
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Tuesday, April 28, 2015

The 'Silly Walk' of a Motor Protein is Revealed

Monty Python's Ministry of Silly Walks has a new addition: the pivoting gait of a motor protein that transports cargo throughout the cell. This walk has been imaged by researchers at the University of Oxford, who first had to develop a new high-speed imaging technique.

Cells rely on a transport system to move cargo in, out, and around the cell. This intracellular highway is made up of long protein chains known as actin filaments. Motor proteins such as myosin 5a walk along the actin "roads", carrying various organelles throughout the cell. Because myosin proteins are only a few tens of nanometers in size and because they move very rapidly across the actin, it has been impossible until now to decipher their walking pattern.

This video replicates the rigid walk discovered by the Oxford group, here modeled with flying sweets, pliable balls, and climbing gear (with two nuts acting as the myosin). The protein pivots compass-like over the actin filament in fixed increments of 74 nanometers, binding to the filament with each step.




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Friday, April 24, 2015

New Technology Could Better Detect Dangerous Materials At US Ports

Image credit: Tristan Taussac via flickr | http://bit.ly/1HZOFqn
Rights information: http://bit.ly/1haBUhX
It is the stuff of scientists' nightmares and science fiction writers' plot points: a nuclear weapon is slipped into the U.S. on a cargo ship and detonates, destroying an American seaport and killing a million people.

Indeed, in the movie version of Tom Clancy’s book, The Sum of All Fears, a smuggled bomb destroys Baltimore.

Earlier this month, physicists -- gathering in Baltimore -- at an American Physical Society meeting, described a new way to detect an atomic bomb in cargo that might have saved the fictional version of the city. It involves blasting precisely tuned gamma rays at freight containers and seeing what passes through a detector.

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Thursday, April 23, 2015

Hubble Turns 25: Our Top 5 Images and an Anniversary Reveal

The Hubble Space Telescope turns 25 tomorrow and like many other science organizations, we've compiled a list of some of our favorite Hubble images over the years. Stay tuned to the bottom where we will reveal the official 25th anniversary image, unveiled by NASA and ESA just a few hours ago.

1. Mystic Mountain

Credit: NASA, ESA, and M. Livio and the Hubble 20th Anniversary Team (STScI)
The Hubble team revealed this striking image of a stellar nursery on the 20th anniversary of the telescope. Reminiscent of the famous "Pillars of Creation" image, this view shows a star-forming pillar in the Carina Nebula. At the tips of the columns, new stars are being formed from the gravitational collapse of dense regions of gas and dust. Once the pressure in the core of the new star is high enough, nuclear fusion will begin and the star will ignite, blowing away the leftover material nearby. 
I particularly love this image because of the twin jets visible at the very tip of the highest pillar. These jets are common as the collapsing newborn star continues to accrete material. They can extend for light years and create strong shock waves in the surrounding material.


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Wednesday, April 22, 2015

Podcast: Wine Physics



Richard Feynman once commented that “if you look at a glass of wine closely enough, you will see the entire universe.” On today’s podcast, we take a little wine tour of our own, to explore some of the physics behind the reds, whites, and rosés. First, we catch up with Martino Reclari, an expert on oenodynamics: the physics of wine swirling. Reclari and his collaborators developed a mathematical treatment of the standing wave patterns formed in a glass as it’s shaken. The three dimensionless parameters they derived can be applied to any container size, from the glass in your hand to the thousand-liter bioreactors mixing nutrients to cultivate cells. The work was nominated for an Ig Nobel Prize in 2012, but Reclari isn’t shaken. “In a sense, it’s a bit scary being nominated for that. It means your research is a little weird and not very useful,” he says, “but in fact...the research nominated is usually research that increases understanding of the normal people of the physics, so why not?”

Close-up view of a refractometer used to measure the sugar content in grapes.
Image Credit: Meg Rosenburg

The second stop on our physics-of-wine tour takes us out into the field with Matthew Rawn, co-owner of Two-Mountain Winery in Washington’s Yakima Valley. Rawn describes how a hand held instrument called a refractometer helps winemakers make harvest decisions by measuring the sugar contents of the grapes on the vine. Light passing through a sample of grape juice is bent, or refracted, by different amounts depending on the exact proportion of sugar and water in the juice. The refractometer measures that angle of refraction and compares it to the Brix scale, which lets winemakers decide when to bring in the harvest, depending on the varieties of wine they want to make.


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Tuesday, April 21, 2015

Plankton Become Stealthy When They Swim Breaststroke

Plankton and other tiny swimmers need to move around in order to find food and reproduce, but if they splash too much, they could easily become food themselves. According to new research by scientists in Denmark, this dilemma is solved by adopting the breaststroke, a naturally stealthy mode of swimming that can allow plankton to pass unnoticed by larger predators.

A planktonic copepod under a microscope. Credit: Chris Moody via flickr


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Monday, April 20, 2015

The Science Of Beer Brewing

Originally published: Apr 16 2015 - 8:45am, Inside Science TV
By: Karin Heineman, Executive Producer

(Inside Science TV) – Beer! Most Americans choose it over all other alcoholic beverages.

It's also one of the world's oldest beverages. In fact the first evidence of beer production dates back to Ancient Egypt and Mesopotamia in the fifth millennium BC. People have been brewing beer for a very long time, even before anyone really understood what turns its ingredients into alcohol.

So what's the science behind beer? Cynthia McKelvey, a science journalist at the University of California Santa Cruz and beer enthusiast, breaks down the brewing process for us in a few simple steps.


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Friday, April 17, 2015

Found Physics - Scratch Holograms

I'm always intrigued when I stumble across a cool physics phenomenon that most people would tend to pass by without a second thought. One of my favorite overlooked physics effects is scratch holograms. They can turn up just about anywhere you have a polished surface that gets scratched in patterns that are surprisingly easy to produce. In fact, most of the scratch holograms I've seen have been accidental.

While I was at the annual APS April Meeting in Baltimore last weekend, I found these patterns on just about all the tables scattered around the hotel where we were gathered to talk about black holes, gravitational waves, cosmic rays and other hardcore physics topics.

video

In the video, you can see a coin I set on the table to show you where the surface is. As I moved the camera back and forth, there appeared to be a shifting reflection. And it is indeed a type of reflection, but the pattern isn't a reflection of something above the table - it's a 3D pattern that appears to be several inches inside the table. That is, it's a hologram image encoded in the scratches on the table surface.


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Thursday, April 16, 2015

Survival Of The Shiniest: Iridescence And Defense In Nature


The color-shifting displays prevalent in nature could puzzle potential predators.

Originally published: Apr 14 2015 - 7:15pm, Inside Science News Service
By: Ker Than, Contributor

(Inside Science) — The rainbow-hued shimmer of fish scales, bird feathers, and insect bodies that change color and brightness depending on viewing angle can be mesmerizing, but biologists have long debated the purpose of the striking displays and why they are so widespread in nature.

Different organisms have evolved various mechanisms to produce iridescence, but most of them rely on light-manipulating structures. Peacocks, for example, have feathers that contain very small protein structures that break up incoming light waves and then recombine and reflect them as vibrant colors.

Image credit: By Benjamin444 (own work) | http://bit.ly/1ze70c7
Rights information: Wikimedia Commons | http://bit.ly/cEcCkh





















It's been suggested that iridescence, also called "interference coloration," plays a role in sex or species recognition. Another hypothesis is that the structures that create iridescence help repel water or reduce friction or help in regulating body temperature, and that the pretty visuals are only a side effect.

Now new research suggests there is another possibility: that for some organisms, iridescence evolved as an anti-predator defense to dazzle and confuse predators with sudden shifts in color and brightness in a bid to gain a few precious moments for escape.

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Wednesday, April 15, 2015

Podcast: The Muon Camera



Particle detectors don't always have to be massive, expensive machines at cutting edge physics laboratories. Undergraduate physics students Kristina Pritchard and Shemaiah Khopang, both at Missouri Southern State University, worked with their faculty advisor David McKee to build a muon detector out of a Sony digital camera.

Taking the camera apart. Image: Kristina Pritchard


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Tuesday, April 14, 2015

Going to Mars: How Will We Get There and Who Should Go?



Would an all-female crew make sense on a deep space journey to Mars? Would the spacecraft rotate to simulate gravity? What's being done now to prepare for such a journey?

These were some of the questions addressed last Thursday by a panel of space scientists, writers, and engineers gathered in downtown DC to talk about the challenges of going to Mars. The discussion, called Giant Leap: The Race to Mars and Back, was organized by Future Tense, a collaboration between Slate magazine, the New America Foundation, and Arizona State University.

Phil Plait of Bad Astronomy moderated the first discussion and jumped straight in by asking what it is we need to do to get to Mars.


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Friday, April 10, 2015

Physics Life Hack Number 3 - Getting Your Ride Out of a Rut, Without a Tow Truck

This Wrangler isn't stuck, because Jeeps are awesome off-road.

This is a handy trick I've had to use a few times, primarily because of my obsession with driving in places where I probably shouldn't.

Back when I had a Jeep Wrangler and a lust for exploring woodland trails and lonely beaches, I would occasionally find myself literally stuck in a rut, with no other vehicles around to help me out. Sometimes a bit of digging, a few properly place pieces of wood or rocks, or plain old pushing would be enough to free my old jalopy. When that didn't work, it was time to grab the rope and rely on physics to set myself free.


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Thursday, April 09, 2015

Beaded Chains Groove to the Music

Here are a wonderful couple of videos showing beaded chains grooving to the music.

Of course in reality the chains are being shaken by a vibrating platform, but the swirling patterns and spirals that spontaneously form lends a lovely charm to an otherwise dull set of chains. In the first video, the blue and red chains seem to be engaged in an intricate and lively dance of give and take (watch in HD for the best effect). The images taken 5 seconds apart and sped up to 10 frames per second to create the video.


These videos were created by Justin Bondy, a former master's student at the University of Toronto, and his supervisor, Stephen Morris, with the aim of studying the separation of DNA strands during cell division. They hoped the two chains would create an experimental model that could shed light on how two-dimensional polymers unmix at much smaller scales.

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Wednesday, April 08, 2015

Hollywood Earthquakes



Next month, a new disaster thriller starring Dwayne “the Rock” Johnson will hit theaters, plunging audiences into chaos and destruction following a magnitude nine earthquake on the San Andreas fault. There’s nothing wrong with encouraging earthquake preparedness, but, as the new trailers make abundantly clear, San Andreas promises to be packed with far-fetched ideas about how earthquakes (as well as tsunamis) work.

To find out what Californians should and shouldn’t be worried about — and why — we spoke with Dr. Belle Philibosian, an earthquake geologist at the Institut de Physique du Globe de Paris, who studies the seismic potential of fault systems. Philibosian has seen her fair share of Hollywood earthquake myths, starting with 1978’s Superman, in which Lex Luthor attempts to trigger the San Andreas fault with a nuclear bomb in a sinister plot to create beachfront property in the desert.


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Tuesday, April 07, 2015

Watch Cosmic Rays Live and Play 'I Spy' for Neutrinos

A recently completed neutrino detector called NOvA has an online webcam where you can watch cosmic rays collisions in near real-time. Since most of us aren't lucky enough to have a cosmic ray detector at home, this webcam is a nice reminder of just how ubiquitous these energetic particles from the cosmos really are.

Created from screenshots of the the NOνA Far Detector Event Display

 The zoo of cosmic ray particles is a whole field of study unto itself with many projects trying to determine the exact composition of particles and from where they originate. But for the physicists trying to study neutrinos these cosmic rays are all just noise.

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Monday, April 06, 2015

Research Projects Reveal How Wrinkles Form

Understanding wrinkles begins with math.


Originally published: Apr 6 2015 - 9:00am, Inside Science News Service
By: Peter Gwynne, Contributor

(Inside Science) – From raisins to fingerprints, and from tree bark to the surface of the brain, wrinkles appear throughout nature. But scientists have struggled to explain how wrinkles form.

Now two independent research teams at the Massachusetts Institute of Technology in Cambridge have developed key insights into the process.

One group has developed a mathematical theory, confirmed experimentally, that predicts how wrinkles take shape on curved surfaces. The other explains in more general terms how layered materials form different types of wrinkly patterns.

Image credit: Changyong Cao and Xuanhe Zhao

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Friday, April 03, 2015

Bicycle Safety: How does Volvo's new invisible reflective paint work?

An invisible yet highly reflective spray paint debuted in the UK a few days ago, as part of a campaign by Volvo Car to increase cycle safety. Life Paint promises to be invisible on clothes and bikes, washable and non-permanent. But the glare of a headlight will cause particles in the paint to reflect light back to the driver, making the cyclist glow.

How does this direction-dependent paint work and can it really make a cyclist safer?

Credit: Screenshot from the Volvo Car Life Paint video campaign

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Thursday, April 02, 2015

This Year's Top 12 Science April Fools

Now that all the dust has settled from yesterday, and we can once again safely read news articles without fear of being pranked, it's a great time to look back at this year's 12 best science April Fools jokes. No, really!

12) Science video star and pioneer selfie documentarian Veritasium warned alerted the world that the planet's equator is slipping south 25 kilometers a year.



11) APS's own Physics highlighted the newfound benefits of carbon nanotubes in toothpaste.



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Wednesday, April 01, 2015

Podcast: Entropy



On the podcast this week, we're delving into entropy, the thermodynamic property that causes heat to flow into cooler areas, buildings to degrade away and ultimately the heat death of the universe. In essence, entropy is how much disorder or randomness there is in a system. This year is an important year for entropy too, it's been 150 years exactly since physicist Rudolf Clausius first published his paper that coined the term "entropy," and formalized what it was, and how it behaved.

The idea of entropy had been around since the early 1800s when scientists like Lazare Carnot first started to realize that in any action, some amount of energy was bing lost. Perpetual motion machines are impossible because some of their energy is inevitably lost to friction and heat.

Perpetual motion machines are as old as science itself, and they all have one thing in common.
They don't work.




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