Friday, July 29, 2011

Geostationary orbit: Are satellites faster than the space shuttle?

Two colleagues and I went out for lunch today and one of them asked what the word 'geosynchronous' meant. It's a term to describe the orbit of a satellite that appears to be stationary over the Earth, we answered, and then we all three pushed our imaginary glasses up the bridge of our noses.

We were half right with our explanation. Geosynchronous is a term used to describe the orbit of a satellite that moves at the same speed that the Earth rotates about its axis. However, because this orbit can be titled over the Earth like an angel with a lopsided halo, the satellite can appear to move north and south in the sky throughout the day, though it always stays over the same line of longitude.

A geostationary orbit, the one we often think of when we hear the word "geosynchronous," is when a satellite is in a geosynchronous orbit over the equator. In this kind of orbit, the satellite appears to be stationary over the Earth.

In the same way that a square is always a rectangle but a rectangle isn't always a square, a satellite in a geostationary orbit is always in a geosynchronous orbit, but not the other way around.
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Thursday, July 28, 2011

Earth Is Getting Fatter

A new analysis of satellite data shows that melting glaciers are contributing to a planet that is bulging around the center.

[From the thinning of ice sheets to the flow of water through aquifers and the slow currents of magma inside Earth, measurements of the amount of mass involved provided by GRACE help scientists better understand these important natural processes. Image courtesy of NASA.]

Like many of its inhabitants, the Earth is getting thicker around the middle -- that's what a new study out this week says. The increased bulge is due to the melting of the Greenland and Antarctic ice sheets.

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Wednesday, July 27, 2011

Nanoscale cell surface patterns might help doctors detect cervical cancer

The role of chemistry and biology in medicine might be considered obvious with the role of physics maybe less so. When it comes to diagnosing cervical cancer, though, the first detective work is purely physical. What physics “detectives” are now seeing through the magnifying glass might make early detection of cervical cancer even easier.

[Fractal patterns of cell surfaces seen at the nanoscale could help doctors detect cervical cancer at the early stages. Photo courtesy of Igor Sokolov.]

For some time, doctors have known that from up close, tumors look disorderly compared to normal cells. Igor Sokolov, a physics professor and director of the Nanoengineering and Biotechnology Laboratories Center at Clarkson University in Potsdam, N.Y., has exposed what researchers have long expected to see – that from the chaos of cervical cancer cells emerges patterns called fractals. Finding fractal patterns in these cells might help pathologists detect cervical cancer more easily.
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Tuesday, July 26, 2011

A Scientific Beer on Neil DeGrasse Tyson

We all like food – well, I assume we do. But the best kind of meal is when you can eat, drink and ask a scientist questions. All this (and more!) can be found in the comfort of a science café.

[Dr. James Gates (UMD) casually explains strings in the Science Café.
Photo Credit: Courtney Lemon]

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Monday, July 25, 2011

More from Comic-Con 2011

Last night was the end of this year's Comic-Con International convention in San Diego. The Physics Central team handed out thousands of comic books to comic book fans from around the world. Here are a few pictures taken over the last few days of Comic-Con.

[The Physics Central team handed out free comic books to passers-by at the San Diego Convention Center.]

[The Physics Central team was also giving out LED pins to Spectra fans.]

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Friday, July 22, 2011

Comic-Con: Building a real Iron Man suit?

Could you really build an Iron Man suit? If so, how close are we to making one? Closer than you might think, says one neuroscientist at this year's Comic-Con International.


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Thursday, July 21, 2011

Comic-Con 2011 Preview Night

[Spectra and her cardboard look-alike are ready to greet fans during Preview Night at Comic-Con.]

The APS Outreach team is once again in San Diego for this year's Comic-Con International! During last night's preview night, the team passed out free
comic books about the laser superhero Spectra and the classic Tesla v. Edison comic.

[Classic comics on sale at Comic-Con 2011.]

Kids ran up to the real-life Spectra for hugs and autographs and the team handed out about 3,000 copies of each comic over the three-hour preview. Several visitors to the booth came for the third installment of the Spectra series, having collected Spectras one and two last year. One young visitor told the team about how her class read the Spectra comics aloud in school.
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Wednesday, July 20, 2011

Deepwater Horizon Study Offers New Insight

A Deepwater Horizon study has improved understanding about the environmental impact of oil spills.


Two months after the deadly explosion of the Deepwater Horizon drilling platform in April 2010, a scientific team had a unique opportunity to gain some knowledge from the disaster. Working from a ship directly above the spill created by the explosion, the team used a robotic vehicle to monitor the chemical composition of the oil and gas gushing from the open wellhead.

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Tuesday, July 19, 2011

Antiferromagnetic People

Be thankful for your stressed out colleagues - they may be keeping you cool.



People, it seems, are much like magnets. Not just in their obvious attraction and repulsion tendencies, but also in their tendency to anti-align. You know the behavior I'm talking about - take two bar magnets, place them near each other, and unless their poles are in opposite directions, one of them will flip over.

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Friday, July 15, 2011

Friday Fermi Problem: Eating the Iron Skillet

I was watching Wheel of Fortune the other night (big money!) and saw this public service announcement from Vanna White:


And thus, a Fermi problem was born.

Let's assume you eat all of your meals after they were freshly prepared in an iron skillet (hello, scrambled eggs!!!). Each meal, you would eat a little bit of your skillet. How long will it take before you've consumed your entire skillet and you'll have to trudge down to the store to buy a new one? (More scrambled eggs, yay!)

Years? Centuries? Eons? Go, Fermi, go! Check back Monday for our answer.
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Thursday, July 14, 2011

Did Colossal WWII Bombing Raids Alter Weather?

Research findings give credence to theory that airplane contrails might alter weather on the ground.


On May 11, 1944, a warm and cloudless spring day, U.S. Army Air Force B-24 Liberators, B-17 Flying fortresses and their fighter escorts lifted off from airfields across southeast England. They climbed, circled, and then formed into one huge formation before heading out to bomb targets in Nazi-occupied Europe.

The bombers and hundreds of fighters flying escort, forming two missions four hours apart, filled the sky with contrails. Researchers from Lancaster University and the Environmental Agency in the U.K. combed through military and meteorological records and determined that the vast cloud cover created by aircraft condensation trails -- or contrails -- slowed the rise of temperatures on the ground that morning.

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Wednesday, July 13, 2011

The Neuron Whisperers

New techniques allow scientists to hear what neurons are saying -- and to talk back.

[A fluorescent image of the cellular doughnut reveals the connections (red) between individual neurons (blue). Image Courtesy of the University of Pittsburgh/ISNS.]

Hundreds of billions of neurons tangle together into the two pounds of folded, wrinkly tissue we call the brain. Scientists have spent years trying to eavesdrop on electrochemical signals -- neuronal chatter -- to figure out what happens when a memory is formed or an emotion is felt. Scientists have recently moved beyond implanting electrodes and using functional MRI scans to begin harnessing the power of cell culture and microchips.
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Tuesday, July 12, 2011

Book Review: "Feynman" by Ottaviani and Myrick

The life story of Richard Feynman is one that in science circles is oft told, and many of his exploits are already the stuff of legend. His effusive personality coupled with his brilliant mind has earned him an almost mythical status in the annals of science.

It takes an especially keen eye to be able to retell his well-worn tales in a way that’s truly new and innovative. Author Jim Ottaviani and artist Leland Myrick's new graphic novel Feynman stands out. It strings together favorite Feynman stories, and some less well known tales, into an intimate, sometimes hilarious and oftentimes moving portrait of the life of this Curious Character.

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Monday, July 11, 2011

Neutrinos and antineutrinos might "disappear" differently, going against the standard model

Scientists working on the MINOS experiment at Fermilab say they may have detected for the first time a difference in the way muon neutrinos and antineutrinos disappear. If they're right, it could change particle physics as we know it.

[The MINOS experiment Far Detector, located in northern Minnesota. Photo credit: Jon 'ShakataGaNai' Davis.]

A fundamental of the standard model of particle physics called "CPT symmetry" requires that the way a particle and its antiparticle disappears be the same. The MINOS experiment has shown that this may not be the case.
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Friday, July 08, 2011

The Physics of Six Flags

This Wednesday, we had a small committee meeting at Six Flags America in southern Maryland. The meeting agenda included a break in the afternoon to do some "classical mechanics research" (including pulling 3 Gs on a roller coaster) which I now present to you!

[Accelerometer data from the Superman roller coaster. Click on the image to enlarge. Orange shows acceleration in the Y-axis (up and down) and blue in the X-axis (left and right) over time; red shows the change in altitude (height) over time. Graph created in DataStudio by PASCO.]

The research included wearing a vest on roller coaster rides that measured our change in altitude and the g-forces we encountered. A device, called an accelerometer, tucked in the vest actually did the measurements, recording our accelerations left and right, up and down, forward and backward as well as charting our changes in height above the ground.
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Thursday, July 07, 2011

Godspeed Atlantis; Goodbye shuttle program

In honor of tomorrow's (scheduled) final launch of the space shuttle, here's a post dedicated to the space shuttle program, including links to web pages you shouldn't miss as you ready for the launch.

[Yes, I spent a half hour at work today watching this video. It made me a little misty-eyed. Video credit: NASA]

What has the space shuttle done for me?
Space exploration has given us developments that affect our everyday lives, many of which can be seen in NASA's Space City interactive graphic. Developments from shuttle program, in particular, have given us improvements that extend to many realms of everyday life on Earth.

For example, in 1983, a NASA contractor developed a safety net for astronauts working on the orbiters. The net was designed to be small, fire resistant, and have lots of tensile strength (the strength to withstand stretching without warping). The net sinks faster and fishes deeper, and thanks to its resistance to ultraviolet light, lasts longer, making it useful for fishermen.
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Wednesday, July 06, 2011

An unfortunate name for a cool tool: The Radioactive Orchestra

It’s a musical “Quantum Mechanics for Dummies.” Only it’s not. It’s just musical. And what a pity.

[The Radioactive Orchestra web site.]

From the Kärnkraftsäkerhet och Utbildning (Nuclear Safety and Training Ltd.) in Sweden comes the Radioactive Orchestra – an online music mixer that plays atomic nuclei instead of instruments. (Not only can you hear what a decaying nucleus might sound like, but you can create a sweet beat with it too!)
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Tuesday, July 05, 2011

Sunny Days Possibly Not So Great For Some Hitters

Optometrists say that afternoon games played under bright and sunny skies can make hitting difficult for certain light-sensitive players.



Texas Rangers outfielder Josh Hamilton hasn't had much trouble slugging like an All-Star during night games this season, but has struggled mightily during day games, exaggerating a career-long trend. When he blamed his blue eyes and light sensitivity for the discrepancy, media reports quickly examined the statistics of other light-eyed players and found little difference between most batters' performances in day and night games. But according to some vision experts, there are legitimate reasons why a player might hit worse under the sun than under the lights.

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Friday, July 01, 2011

Singing Bowls, Singing Trees

There's a really cool article from BBC News today about Tibetan singing bowls and how they do what they do. The best part, though, is the high-speed video:


Thanks to the high-speed video, we can see that the Tibetan singing bowls can make water droplets bounce on the water's surface. As the water in the bowl vibrates, it creates waves that are bound by the sides of the bowl.

The bowl changes shape slightly as it is played which makes different wave patterns. The chaos of the various wave patterns interacting with one another causes droplets to form, some of which can bounce on the surface of the water.

Hearing the singing bowl makes me think of another singing work of art:


Have a singing weekend!
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