Tag: the journal Nature (page 1 of 2)

See Saturn moon’s ‘soda ocean’ shooting to surface in sheets

 Excerpt from  cnet.comEnceladus may have a warm ocean beneath its icy surface, but it may also be shooting through that crust in big sheets, perhaps filled with sea monkeys.       We already know that Saturn's ...

View Article Here   Read More

Mysterious Glow Detected At Center Of Milky Way Galaxy

In this image, the magenta color indicates the mysterious glow detected by NASA's NuSTAR space telescope.Excerpt from huffingtonpost.com A mysterious glow has been observed at the center of the Milky Way, and scientists are struggling to figure o...

View Article Here   Read More

IBM advances bring quantum computing closer to reality

ibm research jerry chow
Research scientist Jerry Chow performs a quantum computing experiment at IBM's Thomas J. Watson Research Center in Yorktown Heights, N.Y. Jon Simon/IBM

Excerpt from computerworld.com
By Sharon Gaudin

IBM scientists say they have made two critical advances in an industrywide effort to build a practical quantum computer, shaving years off the time expected to have a working system.

"This is critical," said Jay Gambetta, IBM's manager of theory of quantum computing. "The field has got a lot more competitive. You could say the [quantum computing] race is just starting to begin… This is a small step on the journey but it's an important one."

Gambetta told Computerworld that IBM's scientists have created a square quantum bit circuit design, which could be scaled to much larger dimensions. This new two-dimensional design also helped the researchers figure out a way to detect and measure errors.
Quantum computing is a fragile process and can be easily thrown off by vibrations, light and temperature variations. Computer scientists doubt they'll ever get the error rate down to that in a classical computer.

Because of the complexity and sensitivity of quantum computing, scientists need to be able to detect errors, figure out where and why they're happening and prevent them from recurring.

IBM says its advancement takes the first step in that process.
"It tells us what errors are happening," Gambetta said. "As you make the square [circuit design] bigger, you'll get more information so you can see where the error was and you can correct for it. We're showing now that we have the ability to detect, and we're working toward the next step, which would allow you to see where and why the problem is happening so you can stop it from happening."

Quantum computing is widely thought to be the next great step in the field of computing, potentially surpassing classical supercomputers in large-scale, complex calculations. 

Quantum computing would be used to cull big data, searching for patterns. It's hoped that these computers will take on questions that would lead to finding cures for cancer or discovering distant planets – jobs that might take today's supercomputers hundreds of years to calculate.

IBM's announcement is significant in the worlds of both computing and physics, where quantum theory first found a foothold.

Quantum computing, still a rather mysterious technology, combines both computing and quantum mechanics, which is one of the most complex, and baffling, areas of physics. This branch of physics evolved out of an effort to explain things that traditional physics is unable to.

With quantum mechanics, something can be in two states at the same time. It can be simultaneously positive and negative, which isn't possible in the world as we commonly know it. 

For instance, each bit, also known as a qubit, in a quantum machine can be a one and a zero at the same time. When a qubit is built, it can't be predicted whether it will be a one or a zero. A qubit has the possibility of being positive in one calculation and negative in another. Each qubit changes based on its interaction with other qubits.

Because of all of these possibilities, quantum computers don't work like classical computers, which are linear in their calculations. A classical computer performs one step and then another. A quantum machine can calculate all of the possibilities at one time, dramatically speeding up the calculation.

However, that speed will be irrelevant if users can't be sure that the calculations are accurate.

That's where IBM's advances come into play.

"This is absolutely key," said Jim Tully, an analyst with Gartner. "You do the computation but then you need to read the results and know they're accurate. If you can't do that, it's kind of meaningless. Without being able to detect errors, they have no way of knowing if the calculations have any validity."

If scientists can first detect and then correct these errors, it's a major step in the right direction to building a working quantum computing system capable of doing enormous calculations. 

"Quantum computing is a hard concept for most to understand, but it holds great promise," said Dan Olds, an analyst with The Gabriel Consulting Group. "If we can tame it, it can compute certain problems orders of magnitude more quickly than existing computers. The more organizations that are working on unlocking the potential of quantum computing, the better. It means that we'll see something real that much sooner."
However, there's still debate over whether a quantum computer already exists.

A year ago, D-Wave Systems Inc. announced that it had built a quantum system, and that NASA, Google and Lockheed Martin had been testing them.

Many in the computer and physics communities doubt that D-Wave has built a real quantum computer. Vern Brownell, CEO of the company, avows that they have.

"I think that quantum computing shows promise, but it's going to be quite a while before we see systems for sale," said Olds.
IBM's Gambetta declined to speculate on whether D-Wave has built a quantum computing but said the industry is still years away from building a viable quantum system.

"Quantum computing could be potentially transformative, enabling us to solve problems that are impossible or impractical to solve today," said Arvind Krishna, senior vice president and director of IBM Research, in a statement.

IBM's research was published in Wednesday's issue of the journal Nature Communications.

quantum computing infographics ibm

View Article Here   Read More

Guiding Our Search for Life on Other Earths

The James Webb Telescope

Excerpt from space.com

A telescope will soon allow astronomers to probe the atmosphere of Earthlike exoplanets for signs of life. To prepare, astronomer Lisa Kaltenegger and her team are modeling the atmospheric fingerprints for hundreds of potential alien worlds. Here's how:
The James Webb Space Telescope, set to launch in 2018, will usher a new era in our search for life beyond Earth. With its 6.5-meter mirror, the long-awaited successor to Hubble will be large enough to detect potential biosignatures in the atmosphere of Earthlike planets orbiting nearby stars.
And we may soon find a treasure-trove of such worlds. The forthcoming exoplanet hunter TESS (Transiting Exoplanet Survey Satellite), set to launch in 2017, will scout the entire sky for planetary systems close to ours. (The current Kepler mission focuses on more distant stars, between 600 and 3,000 light-years from Earth.) 

Astronomer Lisa Kaltenegger

While TESS will allow for the brief detection of new planets, the larger James Webb will follow up on select candidates and provide clues about their atmospheric composition. But the work will be difficult and require a lot of telescope time.
"We're expecting to find thousands of new planets with TESS, so we'll need to select our best targets for follow-up study with the Webb telescope," says Lisa Kaltenegger, an astronomer at Cornell University and co-investigator on the TESS team.
To prepare, Kaltenegger and her team at Cornell's Institute for Pale Blue Dots are building a database of atmospheric fingerprints for hundreds of potential alien worlds. The models will then be used as "ID cards" to guide the study of exoplanet atmospheres with the Webb and other future large telescopes.
Kaltenegger described her approach in a talk for the NASA Astrobiology Institute's Director Seminar Series last December.
"For the first time in human history, we have the technology to find and characterize other worlds," she says. "And there's a lot to learn."

Detecting life from space  

In its 1990 flyby of Earth, the Galileo spacecraft took a spectrum of sunlight filtered through our planet's atmosphere. In a 1993 paper in the journal Nature, astronomer Carl Sagan analyzed that data and found a large amount of oxygen together with methane — a telltale sign of life on Earth. These observations established a control experiment for the search of extraterrestrial life by modern spacecraft.
"The spectrum of a planet is like a chemical fingerprint," Kaltenegger says. "This gives us the key to explore alien worlds light years away."
Current telescopes have picked up the spectra of giant, Jupiter-like exoplanets. But the telescopes are not large enough to do so for smaller, Earth-like worlds. The James Webb telescope will be our first shot at studying the atmospheres of these potentially habitable worlds.
Some forthcoming ground-based telescopes — including the Giant Magellan Telescope (GMT), planned for completion in 2020, and the European Extremely Large Telescope (E-ELT), scheduled for first light in 2024 — may also be able to contribute to that task. [The Largest Telescopes on Earth: How They Compare]
And with the expected discovery by TESS of thousands of nearby exoplanets, the James Webb and other large telescopes will have plenty of potential targets to study. Another forthcoming planet hunter, the Planetary Transits and Oscillations of stars (PLATO), a planned European Space Agency mission scheduled for launch around 2022-2024, will contribute even more candidates.
However, observation time for follow-up studies will be costly and limited.
"It will take hundreds of hours of observation to see atmospheric signatures with the Webb telescope," Kaltenegger says. "So we'll have to pick our targets carefully."

Giant Magellan Telescope
Set to see its first light in 2021, The Giant Magellan Telescope will be the world’s largest telescope.

Getting a head start

To guide that process, Kaltenegger and her team are putting together a database of atmospheric fingerprints of potential alien worlds. "The models are tools that can teach us how to observe and help us prioritize targets," she says.
To start, they have modeled the chemical fingerprint of Earth over geological time. Our planet's atmosphere has evolved over time, with different life forms producing and consuming various gases. These models may give astronomers some insight into a planet's evolutionary stage.
Other models take into consideration the effects of a host of factors on the chemical signatures — including water, clouds, atmospheric thickness, geological cycles, brightness of the parent star, and even the presence of different extremophiles.
"It's important to do this wide range of modeling right now," Kaltenegger said, "so we're not too startled if we detect something unexpected. A wide parameter space can allow us to figure out if we might have a combination of these environments."
She added: "It can also help us refine our modeling as fast as possible, and decide if more measurements are needed while the telescope is still in space. It's basically a stepping-stone, so we don't have to wait until we get our first measurements to understand what we are seeing. Still, we'll likely find things we never thought about in the first place."

A new research center

The spectral database is one of the main projects undertaken at the Institute for Pale Blue Dots, a new interdisciplinary research center founded in 2014 by Kaltenegger. The official inauguration will be held on May 9, 2015.
"The crux of the institute is the characterization of rocky, Earth-like planets in the habitable zone of nearby stars," Kaltenergger said. "It's a very interdisciplinary effort with people from astronomy, geology, atmospheric modeling, and hopefully biology."
She added: "One of the goal is to better understand what makes a planet a life-friendly habitat, and how we can detect that from light years away. We're on the verge of discovering other pale blue dots. And with Sagan's legacy, Cornell University is a really great home for an institute like that."

View Article Here   Read More

Mystery space explosion in 1670 solved

Nova Vulpeculae 1670

By Kathy Fey

A mystery explosion in the night sky turns out to have been caused by colliding stars.

One of history’s mysteries revolved around a strange explosion observed in the sky in 1670, long thought to have been the first nova on record. Recent research suggests that this enigmatic event was actually a rare stellar collision.

According to a report by Astronomy Magazine, the so-called Nova Vulpeculae of 1670 was more likely the collision of two stars, which shines brighter than a nova but not as brightly as a supernova.

Observations made with various telescopes including the Submillimeter Array, the Effelsburg radio telescope and APEX have revealed the more unusual nature of the light source – a violent collision.

When the event first occurred, it would have been visible from Earth with the naked eye. Now, submillimeter telescopes are needed to detect the traces left in the aftermath of the event.

When first observed, 17th century astronomers described what they saw as a new star appearing in the head of Cygnus, the swan constellation.

“For many years, this object was thought to be a nova, but the more it was studied, the less it looked like an ordinary nova, or indeed any other kind of exploding star,” said Tomasz Kaminski of the European Southern Observatory.

Having observed the area of the supposed nova with both submillimeter and radio wavelengths, scientists “have found that the surroundings of the remnant are bathed in a cool gas rich in molecules with a very unusual chemical composition,” said Kaminski.

Researchers concluded that the amount of cool material they observed was too much to have been produced by a nova. The nature of the gas debris best fit with the rare scenario of two stars merging in an explosive collision.

The team’s report was published in the journal Nature.

Karl Menten of the Max Planck Institute called the discovery “the most fun – something that is completely unexpected.”

View Article Here   Read More

What our ancient ancestors found beautiful 50,000 years ago

Excerpt from news.discovery.com

The geode (above), described in the latest issue of Comptes Rendus Palevol, was found in the Cioarei-Boroşteni Cave, Romania. A Neanderthal had painted it with ochre.

"The Neanderthal man must have certainly attached an aesthetic importance to it, while its having been painted with ochre was an addition meant to confer symbolic value," said Marin Cârciumaru of Valahia University and colleagues.

The researchers also noted that "the geode was undoubtedly introduced into the cave by the Neanderthal," since they ruled out that it could have originated in the cave itself.

Was the geode used in rituals, or was it just a treasured object of beauty? Its precise meaning to the Neanderthal remains a mystery for now.

Based on archaeological finds, necklaces made out of Spondylus (a spiky, colorful mollusk) were all the rage. (Above)

This specimen has more of a reddish hue, but Michel Louis Séfériadès of CNRS notes that most are "a highly colored, very attractive purplish crimson." Séfériadès added that the shells were valued, early trade items and that they are now "found in the archaeological remains of settlements and cemeteries, in graves, and as isolated finds."

Some of the shells were made into jewelry, including necklaces and bracelets.


We sing about "five gold rings," but the rings would more likely have been ivory back in the day -- as in around 50,000 years ago, before ivory-producing animals were mostly hunted to extinction.
Early humans in northern regions, for example, made rings out of mammoth ivory. A Neanderthal site at Grotte du Renne, France yielded a carefully crafted ivory ring (above), as well as grooved and perforated "personal ornaments," according to archaeologist Paul Mellars of Cambridge University.

Charcoal (shown avove), ochre and other materials were applied to the face by early Homo sapiens as well as by other human subspecies. 

The ochre, used to paint the geode, mentioned earlier, was also used as makeup, hair dye, paint (to create rock and cave art), as well as to color garments.

Early humans used combs made out of shells and fish bones to both comb their hair and as personal decoration. (Above)

The shell from the Venus comb murex, a large predatory sea snail, is just one species that seems perfect for this purpose. Gibraltar Museum researchers Clive Finlayson and Kimberley Brown also found evidence that Neanderthals valued large, elaborate feathers, which the scientists suspect were worn by the individuals. 

Nearly all early cultures had coveted figurines holding probable symbolic value. Some of the earliest carved objects are known as "Venus" figurines. They present women with exaggerated sexual features. Their exact meaning remains unclear. (Above)

Pendants made of animal teeth were common and probably served many different functions, such as showing the hunter's success, offering symbolic protection, and just as fashion. 

Some of the funkiest-looking teeth were made into worn objects.
Animal teeth could be on a gift list dated to 540,000 years ago, and possibly earlier, as a recent study in the journal Nature found that a population of Homo erectus at Java, Indonesia, was collecting shark teeth and using them as tools and possibly as ornamentation.


The world's oldest known musical instrument is a bone flute (Above). While the earliest excavated flute dates to about 42,000 years ago, comparable flutes were probably made much earlier.

Flutes, like most of the items on this list, were not essential to survival, but yet they somehow contributed to the prehistoric peoples' quality of life.

View Article Here   Read More

Scientists: Enceladus may have warm water ocean with ingredients for life

Enceladus ocean
This artist's impression of the interior of Saturn's moon Enceladus shows that interactions between hot water and rock occur at the floor of the subsurface ocean -- the type of environment that might be friendly to life, scientists say. (NASA/JPL-Caltech)

Excerpt from latimes.com

Scientists say they’ve discovered evidence of a watery ocean with warm spots hiding beneath the surface of Saturn’s icy moon Enceladus. The findings, described in the journal Nature, are the first signs of hydrothermal activity on another world outside of Earth – and raise the chances that Enceladus has the potential to host microbial life.

Scientists have wondered about what lies within Enceladus at least since NASA’s Cassini spacecraft caught the moon spewing salty water vapor out from cracks in its frozen surface. Last year, a study of its gravitational field hinted at a 10-kilometer-thick regional ocean around the south pole lying under an ice crust some 30 to 40 kilometers deep.

Another hint also emerged about a decade ago, when Cassini discovered tiny dust particles escaping Saturn’s system that were nanometer-sized and rich in silicon.

“It’s a peculiar thing to find particles enriched with silicon,” said lead author Hsiang-Wen Hsu, a planetary scientist at the University of Colorado, Boulder. In Saturn’s moons and among its rings, water ice dominates, so these odd particles clearly stood out.

The scientists traced these particles’ origin to Saturn’s E-ring, which lies between the orbits of the moons Mimas and Titan and whose icy particles are known to come from Enceladus. So Hsu and colleagues studied the grains to understand what was going on inside the gas giant’s frigid satellite.   
Rather than coming in a range of sizes, these particles were all uniformly tiny – just a few nanometers across. Studying the spectra of these grains, the scientists found that they were made of silicon dioxide, or silica. That’s not common in space, but it’s easily found on Earth because it’s a product of water interacting with rock. 

Knowing how silica interacts in given conditions such as temperature, salinity and alkalinity, the scientists could work backward to determine what kind of environment creates these unusual particles.

A scientist could do the same thing with a cup of warm coffee, Hsu said.

“You put in the sugar and as the coffee gets cold, if you know the relation of the solubility of sugar as a function of temperature, you will know how hot your coffee was,” Hsu said. “And applying this to Enceladus’s ocean, we can derive a minimum [temperature] required to form these particles.”

The scientists then ran experiments in the lab to determine how such silica particles came to be. With the particles’ particular makeup and size distribution, they could only have formed under very specific circumstances, the study authors found, determining that the silica particles must have formed in water that had less than 4% salinity and that was slightly alkaline (with a pH of about 8.5 to 10.5) and at temperatures of at least 90 degrees Celsius (roughly 190 degrees Fahrenheit).

The heat was likely being generated in part by tidal forces as Saturn’s gravity kneads its icy moon. (The tidal forces are also probably what open the cracks in its surface that vent the water vapor into space.)
Somewhere inside the icy body, there was hydrothermal activity – salty warm water interacting with rocks. It’s the kind of environment that, on Earth, is very friendly to life.  

“It’s kind of obvious, the connection between hydrothermal interactions and finding life,” Hsu said. “These hydrothermal activities will provide the basic activities to sustain life: the water, the energy source and of course the nutrients that water can leach from the rocks.”

Enceladus, Hsu said, is now likely the “second-top object for astrobiology interest” – the first being Jupiter’s icy moon and fellow water-world, Europa.
This activity is in all likelihood going on right now, Hsu said – over time, these tiny grains should glom together into larger and larger particles, and because they haven’t yet, they must have been recently expelled from Enceladus, within the last few months or few years at most.

Gabriel Tobie of the University of Nantes in France, who was not involved in the research, compared the conditions that created these silica particles to a hydrothermal field in the Atlantic Ocean known as Lost City.

“Because it is relatively cold, Lost City has been posited as a potential analogue of hydrothermal systems in active icy moons. The current findings confirm this,” Tobie wrote in a commentary on the paper. “What is more, alkaline hydrothermal vents might have been the birthplace of the first living organisms on the early Earth, and so the discovery of similar environments on Enceladus opens fresh perspectives on the search for life elsewhere in the Solar System.”

However, Hsu pointed out, it’s not enough to have the right conditions for life – they have to have been around for long enough that life would have a fighting chance to emerge.

“The other factor that is also very important is the time.… For Enceladus, we don’t know how long this activity has been or how stable it is,” Hsu said. “And so that’s a big uncertainty here.”

One way to get at this question? Send another mission to Enceladus, Tobie said.

“Cassini will fly through the moon’s plume again later this year,” he wrote, “but only future missions that can undertake improved in situ investigations, and possibly even return samples to Earth, will be able to confirm Enceladus’ astrobiological potential and fully reveal the secrets of its hot springs. ”

View Article Here   Read More

Earth’s address within a massive supercluster of 100,000 galaxies ~ Video

Excerpt from cnet.com

Astronomers have mapped the Milky Way's position to the outskirts of a supercluster of galaxies, newly dubbed Laniakea, meaning "Immense Heaven".

The distribution of galaxies throughout the universe is not more-or-less even; instead, galaxies tend to cluster together, bound together by the pull of each other's gravity. These groups can be a variety of sizes. The Milky Way Galaxy, for instance, is part of what is called the Local Group, which contains upwards of 54 galaxies, covering a diameter of 10 megalight-years (10 million light-years).

Click to zoom

But this Local Group is just a small part of a much, much bigger structure, which researchers at the University of Hawai'i Mānoa have now mapped in detail. Coming in at over 100,000 galaxies, the massive supercluster has been given the name Laniakea -- "immense heaven" in Hawaiian.
The new 3D map was created by examining the positions and movements of the 8000 closest galaxies to the Milky Way. After calculating which galaxies were being pulled away from us and which were being pulled towards us -- accounting for the universe's expansion -- the team, led by astronomer R. Brent Tully, was able to map the paths of galactic migration -- and define the boundaries of Laniakea.

Traditionally, the borders of galactic superclusters have been difficult to map, but studying the gravitational force acting on our neighbouring galaxies has provided some important clues. All objects inside Laniakea are being slowly but surely drawn to a single point -- a force known as the Great Attractor, a gravitational anomaly with a mass tens of thousands of times the mass of the Milky Way.

Everything that is being pulled towards the Great Attractor is part of Laniakea -- although it's possible that Laniakea itself might in turn be part of a structure that is larger still.

"We probably need to measure to another factor of three in distance to explain our local motion," Tully said. "We might find that we have to come up with another name for something larger than we're a part of -- we're entertaining that as a real possibility."

The full paper, "The Laniakea supercluster of galaxies", can be read online in the journal Nature.

View Article Here   Read More

Fresh fossil studies push the dawn of man back to 2.8 million years

(Reuters) - A 2.8-million-year-old jawbone fossil with five intact teeth unearthed in an Ethiopian desert is pushing back the dawn of humankind by about half a million years.Scientists said on Wednesday the fossil represents the oldest known repres...

View Article Here   Read More

Monster Black Hole Is the Largest and Brightest Ever Found

Largest and Brightest Black Hole
An artist's illustration of a monster supermassive black hole at the heart of a quasar in the distant universe. Scientists say the newfound black hole SDSS J010013.02+280225.8 is the largest and brightest ever found.

Excerpt from space.com

Astronomers have discovered the largest and most luminous black hole ever seen — an ancient monster with a mass about 12 billion times that of the sun — that dates back to when the universe was less than 1 billion years old.

It remains a mystery how black holes could have grown so huge in such a relatively brief time after the dawn of the universe, researchers say.

Supermassive black holes are thought to lurk in the hearts of most, if not all, large galaxies. The largest black holes found so far in the nearby universe have masses more than 10 billion times that of the sun. In comparison, the black hole at the center of the Milky Way is thought to have a mass only 4 million to 5 million times that of the sun. 

Although not even light can escape the powerful gravitational pulls of black holes — hence, their name — black holes are often bright. That's because they're surrounded by features known as accretion disks, which are made up of gas and dust that heat up and give off light as it swirl into the black holes. Astronomers suspect that quasars, the brightest objects in the universe, contain supermassive black holes that release extraordinarily large amounts of light as they rip apart stars.
So far, astronomers have discovered 40 quasars — each with a black hole about 1 billion times the mass of the sun — dating back to when the universe was less than 1 billion years old. Now, scientists report the discovery of a supermassive black hole 12 billion times the mass of the sun about 12.8 billion light-years from Earth that dates back to when the universe was only about 875 million years old.

This black hole — technically known as SDSS J010013.02+280225.8, or J0100+2802 for short — is not only the most massive quasar ever seen in the early universe but also the most luminous. It is about 429 trillion times brighter than the sun and seven times brighter than the most distant quasar known.

The light from very distant quasars can take billions of years to reach Earth. As such, astronomers can see quasars as they were when the universe was young.

This black hole dates back to a little more than 6 percent of the universe's current age of 13.8 billion years.

"This is quite surprising because it presents serious challenges to theories of black hole growth in the early universe," said lead study author Xue-Bing Wu, an astrophysicist at Peking University in Beijing.

Accretion discs limit the speed of modern black holes' growth. First, as gas and dust in the disks get close to black holes, traffic jams slow down any other material that's falling into them. Second, as matter collides in these traffic jams, it heats up, emitting radiation that drives gas and dust away from the black holes.

Newfound Quasar SDSS J0100+2802
The newfound quasar SDSS J0100+2802 has the most massive black hole and the highest luminosity among all known distant quasars, as shown in this comparison chart of the black hole's mass and brightness.

Scientists still do not have a satisfactory theory to explain how these supermassive objects formed in the early universe, Wu said.

"It requires either very special ways to quickly grow the black hole or a huge seed black hole," Wu told Space.com. For instance, a recent study suggested that because the early universe was much smaller than it is today, gas was often denser, obscuring a substantial amount of the radiation given off by accretion disks and thus helping matter fall into black holes.

The researchers noted that the light from this black hole could help provide clues about the dark corners of the distant cosmos. As the quasar's light shines toward Earth, it passes through intergalactic gas that colors the light. By deducing how this intergalactic gas influenced the spectrum of light from the quasar, scientists can deduce which elements make up this gas. This knowledge, in turn, can provide insight into the star-formation processes that were at work shortly after the Big Bang that produced these elements.

"This quasar is the most luminous one in the early universe, which, like a lighthouse, will provide us chances to use it as a unique tool to study the cosmic structure of the dark, distant universe," Wu said.
The scientists detailed their findings in the Feb. 26 issue of the journal Nature.

View Article Here   Read More

Mysterious plumes in Mars’ atmosphere baffle astronomers

Excerpt from thespacereporter.com

Astronomers are baffled by images of plumes rising from Mars’ atmosphere in images taken by amateur astronomers in March and April 2012.

The plumes were present for about 10 days though their shapes and sizes changed rapidly during that time, from finger-like tendrils to spherical blobs.

Researchers have proposed several possible explanations for the plumes, which are discussed in an article just published in the journal Nature.

Each of the theories being considered poses problems. One theory, for instaqnce, proposes the plumes are caused by the same magnetic influence that causes the aurora borealis, or Northern Lights, on Earth. The movement of electrically charged particles from the Sun, driven by the solar wind towards Earth’s poles, results in these particles colliding with molecules of gas. These collisions produce the strange lights known as aurorae.

In the study, the researchers admit, “Mars aurorae have been observed near where the plume occurs, a region with a large anomaly in the crustal magnetic field that can drive the precipitation of solar wind particles into the atmosphere.”
The problem with this theory is this would only happen if the Sun released an exceptional amount of energetic particles during the time the plumes were seen. Yet the level of solar output in 2012 was nowhere near sufficient to release such a powerful stream of particles, the authors of the paper acknowledge.

They move on to consider another option, namely that the plumes might be clouds high in the Martian atmosphere.

A highly reflective cloud of either water ice, carbon dioxide ice, or dust particles could explain the plumes. But according to computer models, the presence of these clouds “would require exceptional deviations from standard atmospheric circulation models to explain cloud formations at such high altitudes,” explained the paper’s lead author, Agustin Sanchez-Lavega of the Universidad del Pais Vasco in Spain.

The plumes were seen approximately 120 miles (200 km) from Mars’ surface, which is problematic because the highest Martian clouds are seen is 60 miles (100 km) above the planet’s surface. The only way water can condense so far up is if the temperature in that part of Mars’ atmosphere drops 370 degrees Fahrenheit, or 50 degrees Kelvin, below its norm.

Condensation of carbon dioxide would require twice this temperature drop.

A third theory posits the flumes are caused by atmospheric dust. A wind powerful enough to transport dust 111 miles (180 km) above Mars’ surface could occur only around noon, when the Sun’s heat would be strong enough to create such wind currents.

However, the plumes were seen not at noon but in the mornings along the terminator that separates the planet’s day and night sides.
Recently, data from the Hubble Space Telescope was found showing the plumes back in 1997.

View Article Here   Read More

Scientists find oddly behaving ‘inner-inner core’ at Earth’s center

Excerpt from cnet.com Though the seismic waves from earthquakes are best known for their destructive abilities, in the hands of geologists, they can be powerful tools of discovery. A research team at the University of Illinois (UI) has just used th...

View Article Here   Read More

Using X-rays, scientists read 2,000 year old scrolls charred by Mount Vesuvius

Mount Vesuvius today

By Amina Khan 
Excerpt from latimes.com

Talk about reading between the lines! Scientists wielding X-rays say they can, for the first time, read words inside the charred, rolled-up scrolls that survived the catastrophic eruption of Mt. Vesuvius nearly two millenniums ago.
Testing the scroll
Researchers Daniel Delattre, left, and Emmanuel Brun observe the scroll before X-ray phase contrast imaging begins. (J. Delattre)
The findings, described in the journal Nature Communications, give hope to researchers who have until now been unable to read these delicate scrolls without serious risk of destroying them.
The scrolls come from a library in Herculaneum, one of several Roman towns that, along with Pompeii, was destroyed when Mt. Vesuvius erupted in AD 79. This library, a small room in a large villa, held hundreds of handwritten papyrus scrolls that had been carbonized from a furnace-like blast of 608-degree-Fahrenheit gas produced by the volcano.

“This rich book collection, consisting principally of Epicurean philosophical texts, is a unique cultural treasure, as it is the only ancient library to survive together with its books,” the study authors wrote. “The texts preserved in these papyri, now mainly stored in the Officina dei Papiri in the National Library of Naples, had been unknown to scholars before the discovery of the Herculaneum library, since they had not been copied and recopied in late Antiquity, the middle ages and Renaissance.”
So researchers have tried every which way to read these rare and valuable scrolls, which could open a singular window into a lost literary past. The problem is, these scrolls are so delicate that it’s nearly impossible to unroll them without harming them. That hasn’t kept other researchers from trying, however – sometimes successfully, and sometimes not.

“Different opening techniques, all less effective, have been tried over the years until the so-called ‘Oslo method’ was applied in the 1980s on two Herculaneum scrolls now in Paris with problematic results, since the method required the rolls to be picked apart into small pieces,” the study authors wrote. (Yikes.)

Any further attempts to physically open these scrolls were called off since then, they said, “because an excessive percentage of these ancient texts was irretrievably lost by the application of such methods.”
This is where a technique like X-ray computed tomography, which could penetrate the rolled scrolls, would come in handy. The problem is, the ancient writers used ink made of carbon pulled from smoke residue. And because the papyrus had been carbonized from the blazing heat, both paper and ink are made of roughly the same stuff. Because the soot-based ink and baked paper have about the same density, until now it’s been practically impossible to tell ink and paper apart.

But a team led by Vito Mocella of the Institute for Microelectronics and Microsystems in Naples, Italy, realized they could use a different technique called X-ray phase-contrast tomography. Unlike the standard X-ray CT scans, X-ray phase-contrast tomography examines phase shifts in the X-ray light as it passes through different structures.
Using the technique, the scientists were able to make out a few words and letters from two scrolls, one of them still rolled.

Reading these scrolls is difficult; computer reconstructions of the rolled scroll reveal that the blast of volcanic material so damaged its once-perfect whorls that its cross section looks like a half-melted tree-ring pattern. The paper inside has been thoroughly warped, and some of the letters on the paper probably distorted almost beyond recognition.
Nonetheless, the researchers were able to read a number of words and letters, which were about 2 to 3 millimeters in size. On an unrolled fragment of a scroll called “PHerc.Paris. 1,” they were able to make up the words for “would fall” and “would say.” In the twisted, distorted layers of the rolled-up papyrus called “PHerc.Paris. 4,” they could pick out individual letters: alpha, nu, eta, epsilon and others.

The letters in “PHerc.Paris. 4” are also written in a distinctive style with certain decorative flourishes that seemed very similar to a scroll called “PHerc. 1471,” which holds a text written by the Epicurean philosopher Philodemus. The researchers think they were written in the second quarter of the first century BC.

Ultimately, the researchers wrote, this work was a proofof concept to give other researchers a safe and reliable way to explore ancient philosophical works that were until now off-limits to them.

View Article Here   Read More

Older posts

Creative Commons License
This work is licensed under a
Creative Commons Attribution 4.0
International License
unless otherwise marked.

Terms of Use | Privacy Policy

Up ↑