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Showing posts from December, 2010

Happy New Year!

It's just a few more days until the start of the new year. To celebrate, here's a look back at some of the best of NASA's image of the day gallery from 2010. Clicking on each picture will take you back to the original image where you can learn more about the subject and download a higher resolution photo. Happy New Year!

[Space shuttle Endeavor is silhouetted against the Earth's atmosphere as it prepares to dock with the International Space Station on Feb. 9. Photo credit: NASA.]

[This Hubble photo of the Carina Nebula taken in April shows a dense area of newborn stars. Photo credit: NASA/ESA/M. Livio/Hubble 20th Anniversary Team.]

[NASA astronaut Garrett Reisman takes a self portrait during a spacewalk in May as part of the STS-132 mission. The International Space Station and Earth can be seen in the reflection of his visor. Photo credit: NASA.]

[This photo of Saturn's silhouette was taken by the Cassini probe on Feb. 13. In this image, the Sun is behind Saturn, …

Better sunscreen for windows...from beetles?

Researchers at the University of British Columbia are channeling brightly-colored Jewel Beetles in their development of iridescent glass that could help with energy conservation in buildings.

Iridescent objects have surfaces that appear to change color depending on the angle at which they are viewed. Common examples of iridescent objects are soap bubbles, sea shells and butterflies' wings.

The glass developed by the Canadian researchers takes advantage of the properties of iridescent materials to reflect specific wavelengths of ultra violet, visible or infrared light. The reflective properties of the glass allows it to keep warm radiation inside on cold days and outside on hot days.

To learn more about this new research that appeared recently in the journal Nature, listen to this Physics Buzz podcast below:



The Neutrino Hunt

They come from the Sun. They come from interactions between cosmic rays and Earth's atmosphere. They come from exploding stars in the Milky Way and beyond. They pass through you - a trillion a day - and probably don't even know it. They're called neutrinos.

[The Ice Cube team celebrates the completion of the Ice Cube Neutrino Observatory.]

Neutrinos are tiny subatomic particles. They have almost no mass. They have a neutral electrical charge. They pass through matter undisturbed. Accordingly, they're all but undetectable.

Being able to detect neutrinos, however, could help us answer questions about our cosmos - questions about how stars die and about how our Universe was formed.


A week before Christmas, scientists who had been hard at work at the South Pole for the last six summers completed the installation of the world's largest neutrino observatory called 'Ice Cube.' (The scientists worked only during the warmer Antarctic summer months of November through …

Swimming through sand: The secret of sandfish locomotion

We know how airplanes glide in the air and how submarines move through water, but we don't know much about how creatures "swim" through sand. 'Til now...

How an object's shape affects its generation of lift and drag in both the air and in water is well understood. Otherwise, we'd be misplacing submarines all the time. But how objects - animals in particular - create lift and drag in granular materials like sand is less well understood.

A couple of Ph.D. students and their professor have been taking a closer look at what happens when sand-dwelling creatures - like lizards, crabs, snakes and worms - dive below the surface.

Yang Ding and Nick Gravish, along with Daniel I. Goldman, their Georgia Tech professor of physics, have been studying the sandfish lizard, a popular sand-dwelling pet, to see how it maneuvers in its subterranean environment.

Goldman described the sandfish as a little lizard that lives in the desert in North Africa. When startled, it can burrow 1…

December 21 Lunar Eclipse Video

Happy first day of winter!

[Timelapse video of the Dec. 21, 2010 lunar eclipse*]

Early this morning, something happened that hasn't happened in over 300 years - a total lunar eclipse occurred on the same day as the winter solstice, making Dec. 20-21 one of the longest and most unique nights of a lifetime.

Today, Dec. 21, is the winter solstice, the first day of winter in the Northern Hemisphere. The exact moment of the winter solstice - the annual moment when the North Pole is pointed furthest from the Sun - is at 6:38 EST.

Because the Earth's axis is titled, any given area on Earth's surface receives a different amount of sunlight each day. Looking at the diagram below of the Earth's yearlong orbit around the Sun, the Earth at the far right represents its position on the winter solstice.


Since the Northern Hemisphere is 'leaning' away from the Sun during the winter, it experiences shorter days and longer nights. Thanks to the axial tilt, northern points on the E…

The new White House policy on "Scientific Integrity"

The White House Office of Science and Technology Policy issued a memorandum on scientific integrity this Friday in response to President Obama's request early last year for a set of guidelines to encourage transparency among federal scientific agencies and government policymakers as well as the free flow of scientific information to the public.


On March 9, 2009, President Obama issued a memorandum asking his scientific adviser, John P. Holdren, the director of the office of science and technology policy, to develop the guidelines within 120 days. Despite that request, the guidelines are a full year and a half overdue. Ironically, the agencies targeted by the Dec. 17 memo are required to report back to Holdren on their progress in implementing the new policies within 120 days.

In his original memo, President Obama said that "Science and the scientific process must inform and guide decisions of my Administration," and that "The public must be able to trust the science…

Tron: Legacy

Just in case you've been off the Grid (sorry, couldn't help myself), here's a reminder that "Tron: Legacy" opens today!


["Tron: Legacy" Trailer]

Confession: I'd never heard about "Tron" until about a week ago. (I know, I know.) I promise, however, that I really am a nerd. Just a young nerd. Luckily, another slightly older nerd friend a few cubicles over helped me get up to speed. (He told me about watching "Tron" on LaserDisc. What's that?)

The coolest thing about "Tron: Legacy", he said, was how the new movie comes full circle with the old. In the original movie, Kevin Flynn (Jeff Bridges) is turned into data and brought into the computer world by a teleportation laser.

The new film included Clu, Flynn's computer-based alter-ego who hasn't aged in the computer world. To re-create Clu for the sequel, a full-body laser scan of Bridges was taken and brought into a computer. Then, a digital mask of the actor's…

AGU, Part 2: Geophysics is Loud and Icy

By Alaina G. Levine
The AGU Meeting in San Francisco this week was attended by an estimated 16,000 people. The crowds were massive and the lines for Starbucks were long. But perhaps nowhere was the excitement over all things geophysics-remotely-related more apparent during the evening business meetings focusing on each section of the Society.

After overdosing on posters for a few days, I sauntered over to the AGU business meetings and receptions on Tuesday evening, which are kind of like hospitality suites you find at many conferences, but with more hiking boots.

Each AGU section hosts a meeting/party, many with food and open bar. But even with inebriation, the climate still revolved around cutting edge science. In the meeting of the Cryosphere section, the discussion rang around Antarctica. In particular, the speaker, Helen Amanda Fricker, a glaciologist with Scripps Institution of Oceanography at the University of California, San Diego, who was accepting the 2010 Martha T. Muse Prize …

Giant Ice Volcano Candidate Found On Saturn Moon

Strongest evidence for volcanoes spewing out ice from beneath the surface of Titan.



Astronomers have announced the discovery of a potential new ice volcano on Saturn's moon Titan.

Named Sotra, the volcano is more than 3,000 feet tall and has a one mile deep pit alongside it. Surrounded by giant sand dunes, it is thought to be the largest in a string of several volcanoes that once spewed molten ice from deep beneath the moon's surface.

“We think we have found the strongest case yet for an ice volcano on Titan,” said Randy Kirk, a geophysicist with the U.S. Geological Survey in Flagstaff, Ariz. “What we see is not just a flow like we see in other places, it's like a volcanic field would be on Earth.”

Titan is about the size of the planet Mercury but has an atmosphere thicker than Earth's. This makes it incredibly difficult for astronomers to know what's happening on the surface. Planetary scientists, including Kirk, are using NASA's Cassini spacecraft to map the mo…

Putting the G in AGU, Part 1

By Alaina G. Levine

There may be a ring around the Earth, according to a consultant whose poster was presented at the American Geophysical Union (AGU) Annual Fall Meeting this week in San Francisco. And that ring might be affecting climate change.

But before you say “du’oh-f course!” to the idea that there’s a donut of particles circulating around the globe, know this: just as is the case with most controversial ideas in science, people are just about willing to come to blu’ows over it.

And so it was that while meandering through the poster fields of AGU I ran across the consultant’s poster and witnessed two scientists with elevated voices explaining to her that there was no way that there was a ring, akin to one of Saturn’s, ‘round the earth, with nobody knowin’ nothin’ ‘bout it before.

I asked one of the screaming nerds about the research before me and he suggested that she probably saw an anomaly in the climate data and was arguing a ring was the cause. But a ring that would be massive…

Voyager 1 on the threshold of interstellar space

Thirty-three years ago, on Sept. 5, 1977, Voyager 1 was launched for a journey to Jupiter, Saturn and beyond. Since then, we've seen the first space shuttle launch, the birth and death of compact discs, the introduction of the Chicken McNugget and both Bush presidencies. In those 33 years, Voyager 1 has seen quite a bit more and right now the probe is peering into the last reaches of our solar system.


After thirty-three years of zipping away from the Earth, Voyager 1 has reached the edge of our solar system, entering a realm where the Sun's plasma (hot ionized gas) no longer journeys.

Six years ago, the space probe left the "heliosphere," the bubble surrounding our solar system which is filled with charged particles (solar wind) emitted by the Sun, and entered the "helioshealth" - the last frontier before interstellar space.

Since June, scientists monitoring Voyager 1's Low-Energy Charged Particle instrument noticed that the solar wind speed was equal to…

Erta Ale: The Gateway to Hell

In the north of Ethiopia, about a hundred miles west of the southern end of the Red Sea, is a bubbling caldera known as "The Gateway to Hell." To get to it you must travel by camel train through some of the hottest, harshest terrain on Earth while keeping one eye open for the locals with a reputation for hostility.


This is Erta Ale, one of the Earth's oldest continuously active basaltic shield volcanoes so called for their shape resembling a warrior's shield. At the center of the volcano is a perpetually-bubbling lava lake every bit as menacing as it sounds.

Shield volcanoes form when rock deep in the Earth heats to its melting point and rises through conduits and fractures until it punches through the crust. Unlike explosive stratovolcanoes, like Mount St. Helens in Washington state, lava oozes out of shield volcanoes at a more lethargic pace.

Shield volcanoes are the biggest volcanoes on earth. They are short but wide with widths 20 times their heights. Their typical…

Holiday Instability

It's a typical December scenario: The family trip to the tree lot. The Fraser Fir tied to the roof of the car. Dad under the branches screwing the stand to the trunk. And the inevitable wobbling of the 7-foot holiday embellishment as it threatens to topple over and onto the floor, scattering needles everywhere. When it comes to holiday decorations, why do we work so hard to put out fragile items easily destroyed by Fifi and Fido? (Not to mention Frank and Francine...)

Holiday decorations are unstable. (We're talking about physics here. We'll leave their emotions aside.) To take a closer look at what we're dealing with, I've considered three of the most popular items from the array of December decor: The Christmas tree, the Hanukkah menorah and, of course, the Festivuspole.

Which of the three is the most likely to topple over when cousin Fred bumps into it after sampling too much egg nog?


Just as you would expect, the answer comes down to center of mass - that poi…

Big Bites Too Stressful For Young Sharks

Computer tests show limits of young great white sharks biting power

They've got the flesh-gouging teeth and the powerful jaw muscles, but a new study suggests young great white sharks 8-10 feet long still have some growing to do before they're able to bite with the same legendary force of their larger elders.

New computer simulations show that the younger sharks just aren't able to handle such an intense bite. "[Their jaws] just couldn't handle the stress associated with big bites on big prey," said Stephen Wroe, a research biologist at the University of New South Wales near Sydney, Australia.

That stress can be substantial. A full grown great white shark can produce close to 4,000 pounds of force as it bites, which is about 20 times more powerful than what a human jaw can produce.

It's understandably difficult to take an in-depth look at a shark bite in the wild, so Wroe and his colleagues turned to a type of computer simulation often used by eng…

Naked Singularities Have Permanent Clothes

The center of a black hole is a mysterious place - a singularity where matter is concentrated into an infinitesimally small point and the laws of physics break down making anything possible. A year ago, a couple physicists said that we might be able to see into a black hole, to see a "naked singularity." Today, three physicists say that's not possible.


In October 2009, Ted Jacobson and Thomas Sotiriou published a paper theorizing that under the right circumstances it could be possible to see the center of a black hole. Now, in a new paper due to appear in Physical Review Letters, three physicists argue the Jacobson/Sotiriou theory, saying that no real-life circumstances would ever allow a singularity to be revealed.

To understand what we're talking about, we first have to understand a black hole's anatomy. A black hole's outer edge - called the event horizon - is defined as the "point of no return" where gravity is strong enough to trap objects tra…

The Pneumatic Pachyderm & Other Bionic Wonders

Inspired by the flexibility of an elephant's trunk, engineers in Germany have developed a "Bionic Handling Assistant" that is both light and flexible and could be used as a third arm in places ranging from industrial workshops to assisted living centers.



The robotic arm, made of lightweight plastic and powered by compressed air, was designed by a team from Festo, a German supplier of pneumatic and electrical automation parts, and the Fraunhofer Institute for Manufacturing and Engineering Automation.

They were inspired by the flexibility of an elephant's trunk which has over 40,000 muscle fibers that allow it to move in any direction. Though it's not yet clear how the robotic arm could really be used, it is eerily similar to a real elephant trunk. That they were able to replicate the unique appendage with little more than plastic and air is pretty cool, too.

If you watch the video above, besides occasionally looking behind the trunk for the rest of the elephant'…

Friday's Siesta Fermi Problem Solution

Fermi Problem Solution:

First, according to a doctor at the siesta competition, less than 30 percent of the contestants actually fell asleep. To make our lives easy, we'll say 100 people (roughly 28 percent) fell asleep.

Next, we'll assume that it took the average napper 10 minutes to fall asleep. Normally, people might average a longer drifting off time, but we're assuming these people are expert nappers capable of falling asleep quickly.

Multiplying those two numbers together, we can say that the total amount of napping done in the contest was 1,000 minutes.

Assuming each of the nappers works an office desk job, each would ordinarily burn 102 kilocalories (kcals) an hour at work. Over ten minutes, those 100 office workers would burn a combined 1699 kcals. Since a person burns about 61 kcals an hour while sleeping, we guess a collective 1016 kcals were burned by the nappers.

By subtracting the number of kcals burned while sleeping from working, we know that the net energy the …

The Return of Fermi Problem Friday: Catching Some Zzzzz's

Newton's first law of motion says that at object at rest tends to stay at rest until acted upon by an outside force - like an alarm clock.



In case you missed it, a group of napping advocates, called the National Association of Friends of the Siesta, hosted a nine-day competition in Madrid, Spain, this October to see who could make the most of a 20-minute nap.

The contest was organized to revitalize the tradition of taking an afternoon siesta - a tradition that is dying out in Spain. Taking afternoon naps is not an uncommon practice around the world, but thanks to today's 24-hour-a-day, 7-day-a-week work lifestyle, fewer people are given the opportunity for a nap.

A 62-year old Ecuadoran man, named Pedro Soria Lopez, beat out 359 other contestants to take home the prize - $1400!!!

Lopez napped for 17 minutes. Though one of the runners-up napped for 18 minutes, Lopez scored extra points during his snooze for snoring at a peak of 70 decibels. (As loud as a vacuum cleaner!)

Contes…

No Free Parking

The first nationwide count of parking spaces demonstrates their high environmental cost.



Next time you're searching for a parking space and someone grabs a spot from right in front of you, it might seem like the last space left on Earth, but ponder this: there are at least 500 million empty spaces in the United States at any given time.

The 250 million cars and trucks on America's roads get a bad rap for being environmentally unfriendly. Climate scientists say that automobiles add an array of greenhouse gases and harmful particulates into the Earth's atmosphere, yet little research has been done to estimate the impact parking spaces -- where those automobiles spend 95 percent of their time -- have on our planet.

"I think it's a surprisingly unknown quantity," said Donald Shoup, a UCLA urban planning professor and author of the book "The High Cost of Free Parking." "[Parking] is the single biggest land use in any city. It's kind of like dark ma…

Women Gush and Grades Go Up

Talking about their values could help women do better in physics courses according to a joint study by the University of Colorado and Stanford University.

I remember my first day of Physics II in college. I sat near the back of the room, one of two or three girls in a classroom full of men led by the stereotypical beard-adorned professor. To call that atmosphere intimidating would be an understatement.

Recent research conducted at the University of Colorado (C.U.) worked to tackle that very anxiety felt by women studying male-dominated subjects, like science, technology, engineering and math, where there's a stereotype that men outperform women.

"Women are affected by the stereotype threat because of the idea that men generally do better than women in physics," Akira Miyake, professor of psychology at C.U. and co-author of the research paper, said.

Six C.U. researchers, half physicists and half psychologists, incorporated writing exercises into an entry-level physics course…