Quarks to Quasars


Advertisments for scanning electron microscopes take you into the world of nano-monsters

Biological flying machine? Terrifying monster of the deep? Nope - this is just a scanning electron microscopy image of a Lamnacarus ornatus, or common mite.

Industrial microscopy company FEI sells a variety of imaging rigs, including the one that produced this image. To show what their SEM machines can do, FEI created an incredible image gallery of shots taken with their equipment. Here is just a tiny subset of what you can see if you visit their site.

Click to embiggen! See more at the FEI image site, which is organized both by subject matter and by type of imaging device.

In the image:

1. A worm found in hydrothermal vents - its mouth can turn inside-out.

2. Here is the same worm with its mouth tucked back inside. Very Alien-esque.

3. Gah! What is that? Oh, only hibiscus pollen

4. Here are the mouthparts of a caterpillar, showing the sensory organs.

5. FEI says this is an “image of sperm tails tangled up in a seminiferous tubule.” The sperm mature inside this tubule before thrusting into the world.

6. This is a coccolithophorid, or tiny marine organism. Yes, it looks completely amazing.

Time crystals: One of the weirdest ideas in physics

Physics is defined by its symmetries, from thermodynamics laws like the conservation of mass and energy, to the principle that the universe is basically the same all over. Symmetry can also suggest some truly bizarre ideas. One of those ideas is time crystals.

The definition of a crystal is simple enough - it’s any solid whose constituent parts are arranged in an orderly, repeating pattern extending out in all three spatial dimensions. Although crystals themselves are defined by their symmetrical arrangement, they actually represent a form of what’s known as spontaneous symmetry breaking in closed systems.

The idea here is that if you have a bunch of free atoms whizzing around, the overall system can display symmetry. But if those atoms suddenly come together to form a crystal, the overall symmetry of the system has been reduced onto one particular subgroup, namely the crystal. The overall spatial symmetry has been been broken, but the periodicity that defines the crystal’s structure means it hasn’t been entirely lost.

While that may be a bit theoretical, it’s all fairly straightforward. The intriguing question is one that is often asked of physical phenomena - if this process exists in the three spatial dimensions, could it also occur in the dimension of time as well? That’s the question currently being investigated by MIT physicist Frank Wilczek, who won the 2004 Nobel Prize along with David Gross and H. David Politzer for their work on the strong nuclear force.

Wilczeck, along with collaborator Al Shapere from the University of Kentucky, has just published two papers examining how the mathematics that govern crystal formations in space could also work in time. They argue that time translation symmetry - the notion that a system will maintain the same features over a given interval of time - can be broken in low energy states and then reduced to a smaller part of the system, which they call time crystals.

The key here is that the system being described is in its lowest energy state, which means that there should be no movement in it at all. But if something inside the system starts moving, then the time translation symmetry has been broken. What Wilczeck and Shapere argue is that these moving objects could simply get stuck in an eternal loop. The periodic movement of the object through time is just like the periodic arrangement of a crystal’s internal structure through space, and the end result is the same - symmetry is broken, but it isn’t lost.

We don’t yet know if time crystals exist, and Wilczeck and Shapere aren’t claiming otherwise - they’re simply saying that it’s mathematically possible for the crystals to exist. There are some real world reasons to think such crystals might exist, specifically in the realm of superconductors. These can carry currents even in their lowest energy state, which is a form of movement, and those electrons passing through superconductors could theoretically keep moving forever.

If time crystals really are out there, we could be looking at some potentially fascinating applications for them. The periodic nature of time crystals means they would perhaps be the most basic, fundamental form of timekeeping in the universe - as Wilczeck writs in one of his papers, “Spontaneous formation of a time crystal represents the spontaneous emergence of a clock.” These time crystals might also have a home in quantum computing, where they could be arranged as qubits and used to undertake calculations at zero energy.

The one thing time crystals won’t give us, however, is perpetual motion. Well, that’s not exactly the case. A time crystal would be able to move periodically forever - which is the literal definition of perpetual motion - but it wouldn’t actually allow us to get any energy from the system, which is generally what people really mean when they refer to perpetual motion. Time crystals would only exist in the lowest energy state, so it would be impossible to gather any usable energy from this eternal loop in time.

For more, check out the original papers here and here. Via Science News and Technology Review. Image by cybrain, via Shutterstock.

(Source: )

Why Do We Yawn? It May Keep Us From Getting Hot-Headed

Yawning may activate a sinus “pump” that ventilates our brains.

In the Image: Chinese paramilitary police officers in Beijing.

Yawning may help you keep a cool head—literally, a new study suggests. The findings might hold some hope for sufferers of insomnia, migraines, and even epilepsy.

Though scientists have put forth various theories for yawning—from fatigue to lack of oxygen—none have held up to scrutiny.

“We can put a man on the moon, but we do not understand what the function of yawning is,” said study co-author Gary Hack, of the University of Maryland School of Dentistry in Baltimore.

Now, Hack and co-author Andrew Gallup, of Princeton University, propose that yawning causes the walls of the maxillary sinus to expand and contract like a bellows, pumping air onto the brain, which lowers its temperature. Located in our cheekbones, the maxillary are the largest of four pairs of sinus cavities in the human head.

Sinus Solution?

In addition to potentially solving the mystery of yawning, the study may also reveal why we have sinuses, whose existence has also stumped scientists.

It’s a “unified theory tying yawning, sinus ventilation, and brain cooling into a neat little package,” Hack said.

Ryan Soose—an ear, nose, and throat doctor as well as director of the University of Pittsburgh Medical Center’s Division of Sleep Surgery—added, “The hypothesis that these two relatively unknown things may be directly related, to me, is very intriguing.”

Cadaverous Clues

In 2002 study co-author Hack and his team were dissecting a cadaver when they discovered that the back wall of the maxillary sinus was much thinner—and therefore more flexible—than described in many medical textbooks.

“I’d always kept that in the back of my mind, because yawning was an exaggerated jaw movement that would have an impact on this previously undescribed pump in humans,” Hack said.

Later, he came across the postdoctoral research of Princeton’s Gallup, who in 2007 had become the first to suggest the brain-cooling theory for yawning.

Yawning Theory May Influence Medicine

Overall, understanding yawning could be a useful tool for diagnosing certain medical conditions, such as epilepsy and migraines, which are both preceded by excessive yawning, the scientists say.

Credits:

Christine Dell’Amore

National Geographic News

Published November 15, 2011

Mars Now at Most Extreme Distance from the Sun

THE GIST
  • Mars is at its farthest point from the sun in its approximate 2-year orbit.
  • Coincidentally, Mars is also fast-approaching opposition, the period in its orbit that brings the planet closest to Earth.

Wednesday (Feb. 15), the red planet Mars swings to aphelion — its farthest point from the sun in its approximate two-year orbit. This chart helps to illustrate Mars, the fourth planet outward from the sun, at aphelion.

In their order going outward, the four inner rocky planets planets are Mercury, Venus, Earth and Mars. The four outer gas giant planets — Jupiter, Saturn, Uranus and Neptune — lie well outside chart.

You can see Mars this evening — or any evening in the coming months — for yourself. The best time to see Mars in this two-year period is almost here, with Earth due to pass between Mars and the sun on March 3, 2012.

Wednesday night, Mars rises above the eastern horizon around 8 to 9 p.m. (local time, as seen from around the globe). The planet is located now in front of the constellation Leo the Lion. Mars, the fourth planet outward from the sun and the next planet outward from Earth, should be fairly easy to spot because the distance between our two worlds is nearly at its least now for this two-year period. Because it’s relatively close, Mars looks like a bright reddish star.

On March 3, 2012, Earth will pass in between the sun and Mars, bringing Mars to opposition. Because Mars stands opposite the sun in our sky at opposition, Mars will rise in the east at sunset and set in the west at sunrise, to stay out all night long in early March 2012. At present, Mars shines from evening until morning dawn.

This 2012 opposition of Mars nearly coincides with Mars at aphelion — Mars’ greatest distance from the sun. Because of this close coincidence of aphelion and opposition, the year 2012 gives us Mars’ farthest and dimmest opposition since its opposition on Feb. 12, 1995. Looking ahead, we won’t see a more distant opposition again until Feb. 19, 2027.

As a general rule, Mars reaches opposition every other year, and far-distant Martian oppositions recur every 15 to 17 years. Extra-close oppositions, whereby an opposition closely aligns with perigee — Mars’ closest point to the sun — also happen in cycles of 15 to 17 years. The last extra-close opposition took place on Aug. 28, 2003, and the next one will be on July 27, 2018.

But any opposition of Mars — whether it’s near or far — counts as extra special. It’s at or near opposition that Earth comes closest to Mars for the year, and that Mars, in turn, shines most brightly in our sky. Watch for Mars to brighten these February 2012 nights, in spite of the fact that this upcoming opposition will be the most distant one in years.

Venus Spinning Slower Than Thought—Scientists Stumped

Mysterious decrease could affect future exploration missions.

by : Jason Major for National Geographic News

On the image: Thick clouds swirl on Venus in a 2007 picture taken from orbit.

Planet lovers take note: Venus is spinning even slower than astronomers thought, according to new data from a European space probe.

In the early 1990s scientists with NASA’s Magellan mission calculated that a single rotation of Venus takes 243.015 Earth days, based on the speed of surface features passing beneath the orbiting spacecraft.

But scientists now mapping Venus’s surface with the European Space Agency’s Venus Express orbiter were surprised to find the same features up to 12.4 miles (20 kilometers) from where they were expected to be, based on the previous measurements.

According to the new data, Venus is rotating 6.5 minutes slower than it was 16 years ago, a result that’s been found to correlate with long-term radar observations taken from Earth.

“When the two maps did not align, I first thought there was a mistake in my calculations, as Magellan measured the value [of Venus’s spin] very accurately,” Nils Müller, a planetary scientist at the DLR German Aerospace Centre, said in a statement.

“But we have checked every possible error we could think of.”

Planet Slowed by Dense Atmosphere?

One possible cause for the slowed spin is friction caused by Venus’ thick atmosphere and high-speed winds. The motion of the atmosphere on Earth, for example, has been observed to affect the planet’s rotation rate, albeit to a much smaller degree.

Thanks to a heavy blanket of carbon dioxide-laden air, the surface pressure on Venus is 90 times what we experience on Earth at sea level, and opaque clouds of caustic sulphuric acid constantly whip around the planet at hurricane speeds.

Still, “it is difficult to find a mechanism that will cause the average rotation rate to change this much in only 16 years,” Venus Express project scientist Håkan Svedhem told National Geographic News.

“The origin of this could lay in the solar cycle or in long-term weather patterns that modify the atmospheric dynamics. But this puzzle is not yet solved.”

Some reports cite an exchange of angular momentum between Venus and Earth as a possible cause for the variation. A moon, for example, can cause a planet to rotate slower than expected, because both objects share angular momentum.

But with 23.6 million miles (38 million kilometers) between the two planets at their closest approach, “there is no exchange of momentum between Venus and the Earth,” Svedhem stated.

Instead, he said, further study is needed to discern the cause—or causes—of Venus’ slight reduction in speed.

Ultimately, he added, it’s important to know exactly how fast the planet is spinning, since any possible future missions to explore Venus will need precise information to chose their landing sites.

World’s Tiniest Chameleons Found in Madagascar

Researchers have recently discovered four new chameleon species, which rank among the world’s tiniest reptiles. Adults of the smallest species are just over an inch from snout to tail.

The four new species belong to the genus Brookesia, also known as the leaf chameleons, which live in remote rainforests in northern Madagascar. The genus is already known to contain some very small species, with members typically resembling juvenile versions of larger species.

As small as these guys are, a super-tiny dwarf gecko found in the British Virgin Islands might be just a tad more wee.

Since the chameleons all look extremely similar, researchers used genetic analysis to determine that they belonged to separate species. The findings appear Feb. 14 in PLoS ONE.

Brookesia species tend to live within a very small range. Half the members of this genus are found in only a single location and the smallest of the newly found species — Brookesia micra — lives only on a small island called Nosy Hara. Extreme miniaturization of this sort is common in island populations. Known as island dwarfism, it may occur due to limited resources and pressure to reproduce faster.

“The extreme miniaturization of these dwarf reptiles might be accompanied by numerous specializations of the body plan, and this constitutes a promising field for future research,” said herpetologist Frank Glaw, lead author of the study, in a press release. “But most urgent is to focus conservation efforts on these and other microendemic species in Madagascar which are heavily threatened by deforestation.”

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The North Star might be shrinking before our eyes

Sailors have navigated by the light of Polaris for centuries, but all is not well with the North Star. There’s something wrong with its light, and the best explanation might be that it’s losing the equivalent of Earth’s massevery year.

That’s the argument put forward by astrophysicist Hilding Neilson and his team at the University of Bonn. The researchers weighed Polaris - specifically the supergiant main star in the Polaris multiple star system - by monitoring how its light cyclically dims and brightens. In case it’s not immediately obvious how this light cycle would reveal a star’s mass, Kate McAlpine over at ScienceNOW explains:

Like all stars, Polaris is made of gas in layers around a core, where nuclear fusion occurs. As its gravity pulls the outermost gas inward, Polaris develops an opaque layer just under the surface that doesn’t let light through easily, dimming its glow. Light then builds up beneath this layer and pushes on it like water vapor boiling up under the lid on a saucepan. That light heats the opaque layer, causing it to expand and making it more transparent. The star becomes bigger and brighter until those outer layers of gas fall inward again and the cycle begins anew.

The thing is that Polaris’s light cycle hasn’t remained constant. Observations made way back in 1844 reveal Polaris’s pulse used to be 12 minutes slower than it is now, and 168 years of data suggest that Polaris’s pulse regularly decreases by about 4.5 seconds each year. That isn’t easily explained by standard theories of star evolution, and the best explanation, according to Neilson, is that Polaris is venting an Earth’s worth of mass into space every year, which would throw off the inner workings of the light cycle just enough to account for this big drop.

Whatever is going on with Polaris, here’s the good news - it shouldn’t affect your ability to navigate the seas in search of the New World. (I assume that’s what we still use it for, though Idid never get past the 1480s in my history textbook.) Neilson says this mass loss is likely just a brief episode in the star’s larger life, and it’s not actually wasting away to nothing. Even if that isn’t the case, we’ll have a new North Star soon enough anyway - Gamma Cephei will move into a closer alignment above the North Pole around the year 3000, so if you can just delay all transoceanic voyages until then, you should be all set.

For more on this story, check out ScienceNOW. Original paper at The Astrophysical Journal Letters. Artist’s conception by NASA, ESA, G. Bacon (STScI).

Spiders Hunt With 3-D Vision

With their keen vision and deadly-accurate pounce, jumping spiders are the cats of the invertebrate world. For decades, scientists have puzzled over how the spiders’ miniature nervous systems manage such sophisticated perception and hunting behavior. A new study of Adanson’s jumping spider (Hasarius adansoni) fills in one key ingredient: an unusual form of depth perception.

Like all jumping spiders, the Adanson’s spider has eight eyes. The two big ones, front and center on the spider’s “face,” have the sharpest vision. They include a lens that projects an image onto the retina—the light-sensitive tissue at the back of the eye. That much is common in animal vision, but the jumping spider’s retina takes things a step further: It consists of not one but four distinct layers of light-sensitive cells. Biologists weren’t sure what all those layers were for, and research in the 1980s made them even more enigmatic. Studies showed that whenever an object is focused on the base layer, it is out of focus on the next layer up—which would seem to make the spider’s vision blurrier rather than sharper.

 This story provided by ScienceNOW, the daily online news service of the journal Science.

Image: Thomas Shahan/Flickr


This bizarre tulip-shaped creature is related to nothing else on Earth

This is Siphusauctum gregarium, a creature that lived in the ocean 500 million years ago. It’s so completely strange that it’s taken scientists 30 years just to figure out how to describe it. It’s literally like nothing else on Earth.

Pluto and Neil deGrasse Tyson

In 2000, the American Museum of Natural History in New York City opened its new Frederick Phineas and Sandra Priest Rose Centre for Earth and Space – simply the Rose Centre – featuring the newly renovated Hayden planetarium. When it came time to organize the display of solar bodies, the museum curators grouped like objects together according to the five major types: the terrestrial planets, the Asteroid Belt, the Jovian planets or Gas Gaints, the Kuiper Belt and the Oort Cloud. Pluto didn’t fit the bill as a terrestrial planet or a Jovian planet, but it did fit with the Kuiper objects so that’s where it ended up. (Left, Neil deGrasse Tyson shows Pluto Pluto.)

A massive solar eruption may lead to the strongest radiation storm in seven years

Last week, a swelling solar storm on the surface of the Sun sent a stream of charged particles hurtling toward Earth, making for beautiful northern lights in the planet’s extreme latitudes. But late last night, at 10:59 p.m. EST, the now massive tempest unleashed an eruption that scientists expect will be responsible for Earth’s largest solar radiation storm since 2005.

How powerful are we talking? The National Oceanic and Atmospheric Administration (NOAA) says that many plane flights scheduled for tomorrow can expect to be re-routed within the next few hours.

Cause for concern is due to the M9-class solar flare that was observed lashing out last night from a large sunspot — dubbed “1402” — on the Sun’s northeastern hemisphere. The image you see up top reveals the extreme flash of ultraviolet radiation that was emitted by the sunspot, as captured by NASA’s Solar Dynamics Observatory [Click here for a mesmerizing hi-res version].

The explosion’s M9-ranking puts it just below the threshold of an X-flare, the most powerful classification of solar eruption there is. It’s important to understand that while flares more violent than 1402’s are often observed on the surface of the Sun, it’s rare for one so powerful to eject subatomic particles in a wave aimed so directly at Earth; analysts at the Goddard Space Weather Lab have released an animated forecast track [click through to see], which shows the leading edge of the particle ejection reaching Earth tomorrow morning, shortly after 9 a.m. EST (1400 GMT).

SpaceWeather.com reports the particles emitted by last night’s solar flare could “cause isolated reboots of computers onboard Earth-orbiting satellites and interfere with polar radio communications.” According to Kathy Sullivan, deputy administrator of NOAA, polar flights scheduled for tomorrow here on Earth are expected to be re-routed within the next few hours, so as to avoid any complications caused by the storm’s arrival.

Read more on NOAA, Spaceweather.com and SPACE.com
Top image via NOAA

The Circus Elephant Retirement Home

Elephants weigh 3 tons and eat 200 pounds of food per day. Sustaining these massive animals is an enormous (and expensive) task. So what happens to circus and zoo elephants when they grow old and can no longer earn their keep by entertaining audiences? They move to a retirement home in Tennessee. Here’s how two elephant trainers created a safe, beautiful place for these animal elders to enjoy their golden years. More »

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