Move Over Saturn, Scientists Find Rings Around Miniature Planet

Posted March 26th, 2014 at 6:01 pm (UTC+0)
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Artist impression of the two rings encircling the mini-planet Chariklo (Lucie Maquet)

Artist impression of the two rings encircling the minor planet Chariklo (Lucie Maquet)

Whenever you think of a planet with rings around it, Saturn probably comes to mind first. Jupiter, Uranus and Neptune – the four outer giant planets - also have rings, but they’re not as bright, wide and colorful as Saturn’s.

However, scientists in Chile now say they’ve discovered the first miniature planet with two rings circling it. The team of astronomers, based at various South American observatories, including the European Space Organization’s La Silla Observatory, says the rings are made of ice and pebbles.

It is the first time astronomers have found rings around any of the smaller celestial objects orbiting the Sun.

The mini-planet is actually a giant asteroid called Chariklo, a celestial body known as a centaur or minor planet. It is believed to have originated in the Kuiper belt, a vast collection of icy celestial objects, but at some point was thrown out. Chariklo, which is about 250 kilometers in diameter, is currently located about 2 billion kilometers away from Earth, between Saturn and Uranus.

The astronomers were able to detect Chariklo’s rings as it passed in front of a star identified as UCAC4 248-108672 on June 3, 2013.

The star seemed to disappear for a few moments as Chariklo blocked its light by passing in front of it, an event known as occultation. The astronomers also noted two very short dips in the star’s apparent brightness: First, a few seconds before, and then again a few seconds after, the star’s light was blocked by the centaur.

These observations led the astronomers to believe that something surrounding the small celestial object was blocking the light.

Another artist impression that shows how the rings might look from close to the surface of Chariklo. (ESO/L. Calçada/Nick Risinger-skysurvey.org)

Artist impression shows how Chariklo’s rings might look from the surface of the minor planet. (ESO/L. Calçada/Nick Risinger-skysurvey.org)

After comparing notes from different observational sites, the team was able to recreate not only the shape and size of Chariklo itself, but also the shape, width, orientation and other properties of its rings.

“We weren’t looking for a ring and didn’t think small bodies like Chariklo had them at all, so the discovery and the amazing amount of detail we saw in the system came as a complete surprise,” said Felipe Braga-Ribas of Brazil’s National Observatory in Rio de Janeiro, who planned the observation campaign and is lead author on the paper published in Nature.

The two narrow rings surrounding Chariklo are about 7 kilometers wide for one ring and 3 kilometers wide for the other. The two rings are separated a gap of about nine kilometers.

“For me, it was quite amazing to realize that we were able not only to detect a ring system, but also pinpoint that it consists of two clearly distinct rings,” said team member Uffe Gråe Jørgensen of the  University of Copenhagen. “I try to imagine how it would be to stand on the surface of this icy object, small enough that a fast sports car could reach escape velocity and drive off into space, and stare up at a 20 kilometer wide ring system 1,000 times closer than the Moon.”

Scientists at the Niels Bohr Institute at the University of Copenhagen developed a special high resolution-camera for the 1.54 meter Danish telescope at La Silla that, according to Jørgensen, played a key role in making the discovery.

Scientists don’t know for sure how the two rings surrounding Chariklo formed but Jørgensen has a theory.

Special hi-res camera system that was specially developed at the Niels Bohr Institute is now sitting on the Danish telescope at the La Silla Observatory in Chile. The camera played a significant role in making the discovery of the rings surrounding Chariklo. (Jesper Skottfelt, Niels Bohr Institute)

Special hi-res camera system that was specially developed at the Niels Bohr Institute is now sitting on the Danish telescope at the La Silla Observatory in Chile. (Jesper Skottfelt, Niels Bohr Institute)

“What we are witnessing is perhaps the unveiling of an object that is in the middle of the same stage of development as the Earth and the Moon 4.5 billion years ago, when there was a giant collision between Earth and another planet,” he said. “In the collision, material hurled out in all directions, forming a circular disc around the Earth, which gradually condensed and formed the Moon. Similarly, we believe that another celestial body crashed into Chariklo and a good deal of material was cast out and formed rings. If the two discs around Chariklo gather and form a moon, it will be approximately 2 kilometers in diameter.”

The project leaders have given the two rings temporary nicknames, Oiapoque and Chuí, after Brazilian rivers.

Researchers Test Real ‘Thinking Cap’

Posted March 24th, 2014 at 7:22 pm (UTC+0)
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Robert Reinhart applies the electrical stimulus to subject Laura McClenahan. (John Russell/Vanderbilt University)

Robert Reinhart applies the electrical stimulus to subject Laura McClenahan. (John Russell/Vanderbilt University)

Teachers often urge their students to  put on their “thinking caps” as a way of encouraging serious thought. However, a real thinking cap could someday become a reality. New research shows it’s possible to control the ability to learn by applying mild electrical current to the brain.

Writing in the Journal of Neuroscience, the Vanderbilt University researchers say the results of their studies could eventually provide help to those wanting to improve their learning abilities and could also be used to treat various conditions such as schizophrenia and Attention Deficit Hyperactivity Disorder (ADHD).

The researchers made their findings after being intrigued by past studies that show a spike in negative voltage within the medial-frontal cortex of the brain milliseconds after a person makes an error. This area of the brain is thought to be responsible for the “oops” reaction whenever an error is made.

The previous research did not explain why this brain reaction occurs, so the Vanderbilt duo decided find out by testing several theories.  They also wanted see if that activity in the medial-frontal cortex would influence the ability to learn since the brain allows us to learn from our mistakes.

“And that’s what we set out to test: What is the actual function of these brainwaves?” said researcher Robert Reinhart, a Ph.D. candidate. “We wanted to reach into your brain and causally control your inner critic.”

The theories Reinhart and research partner Geoffrey Woodman, an assistant professor of psychology, wanted to test was to see if it was possible to control the brain’s electrophysiological – electrical properties of a living cell – response to mistakes, and if the effect could be purposely controlled either up or down depending on which direction an electrical current is applied to it. They also wanted to see how long the effect of the electrical application would last and whether the same methods could be used to control other tasks.

To conduct their tests, Reinhart and Woodman took an elastic cap with two electrodes fastened to saline-soaked sponges; the sponges were applied to the cheek and  crown of the head of the research subjects.

The researchers then applied 20 minutes of very mild transcranial – across or through the skull – direct current stimulation to each of their subjects.

(Quinn Dombrowski via Flickr/Creative Commons)

(Quinn Dombrowski via Flickr/Creative Commons)

During this process, the current traveled from one electrode, called the anodal electrode, which was attached to the crown of the head, through the skin, muscle, bones and brain, and out through the other electrode, or cathodal electrode, attached to the cheek in order to complete the circuit.

“It’s one of the safest ways to noninvasively stimulate the brain,” Reinhart said. “The current is so gentle that subjects reported only a few seconds of tingling or itching at the beginning of each stimulation session.”

The researchers conducted three of these transcranial stimulation sessions. Their subjects were randomly given either an anodal – current sent from the crown of the head to the cheek, cathodal – current sent from cheek electrode to crown – or a fake jolt that merely produced a tingling effect without actually affecting the brain.

After undergoing 20 minutes of trancranial stimulation, the test subjects were given a learning task that involved determining, through trial and error, which buttons on a game controller matched specific colors displayed on a monitor. The researchers would occasionally complicate the tests by showing the subjects a signal that told them not to respond. The subjects had less than a second to respond to each signal correctly, which made it easier for them to make mistakes, providing a number of opportunities for the medial-frontal cortex to fire.

The researchers measured the electrical brain activity of each subject as they made their way through the exercises. The measurements provided the researchers with a way to monitor how the brain changed at the very moment the subjects made an error and how the electrical stimulation influenced changes in brain activity.

Shortly after the researchers sent the current from the crown of the subject’s head to their cheek – an anodal current – they noticed that the spike in negative voltage was almost twice as large on average as without stimulation.

As a result of the anodal stimulation, the researchers found the subjects made fewer mistakes and that they actually learned from their errors faster than they did after a phony jolt was applied.

Portable EEG machine (John Koetsier via Creative Commons/Flickr)

Portable EEG machine (John Koetsier via Creative Commons/Flickr)

When they sent the current in the opposite direction, from the cheek to the crown of the head – cathodal current – the Vanderbilt duo saw the opposite of the anodal result take place.  They noticed that the spike in negative voltage was actually much smaller; the subjects wound up making many more errors and they took longer to learn each task.

The researchers noted that while the positive or negative effects generated by each of the stimulation patterns weren’t detected by the test subjects themselves, the results of each test displayed very clearly on their monitoring devices.

“This success rate is far better than that observed in studies of pharmaceuticals or other types of psychological therapy,” said Woodman.

The researchers said that their tests also revealed that the sessions of electrical stimulation did transfer to other tasks and the effects lasted for about five hours.

Earth’s Natural Climate Control Keeps Planet Livable

Posted March 19th, 2014 at 11:03 pm (UTC+0)
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(Atmospheric Infrared Sounder via Wikimedia Commons)

(Atmospheric Infrared Sounder Wikimedia Commons)

A new hypothesis explains why Earth has remained habitable despite natural events that have robbed other planets in our solar system of their ability to host and sustain life.

As the character Goldilocks exclaimed in the classic fairytale, The Story of the Three Bears, Earth is the one planet in our solar system that’s “just right” to maintain the ideal conditions for life to exist, unlike, for example, Mars that’s “too cold” or Venus that’s “too hot.”

Researchers gathered documented evidence to support their new theory said that one reason Earth has stayed livable is because of the various geologic cycles it’s gone through over millions of years and continues to undergo today.

The scientists, from the University of Southern California in Los Angeles and Nanjing University in China, write in the journal Nature that they have found that the geologic cycles — which alternately release and then absorb atmospheric carbon dioxide — act as a form of climate control to keep Earth in balance.

1912 Illustration of Goldilocks running from the 3 bears - from the fairytale (Wikimedia Commons)

1912 Illustration of Goldilocks running from the three bears – from the fairytale (Wikimedia Commons)

Scientists already understood that new or “fresh” rock pushed up through the Earth’s surface when the world’s mountains formed, acting as sort of a sponge, soaking up carbon dioxide, a common greenhouse gas.

However, researchers also noted that if this process of absorbing greenhouse gas continued unabated without any kind of cut-off switch, levels of atmospheric CO2 levels would have been drained to a level that would have caused the Earth to fall into an endless winter a few million years after major mountain ranges such as the Himalayas began to form. Fortunately for all of us, this unrestrained absorption of atmospheric carbon dioxide did not take place.

Researchers involved with this study said that the same fresh rock that served as a sponge to soak up CO2 also produced carbon through a chemical weathering process which replenishes the atmospheric carbon dioxide at a similar rate.

The Himalayas as seen from the International Space Station (NASA)

The Himalayas as seen from the International Space Station (NASA)

“Our presence on Earth is dependent upon this carbon cycle. This is why life is able to survive,” said the Mark Torres, from USC, lead author of the study.

The researchers studied samples of rock taken from the Andes Mountains in Peru.  They noticed an abundance of pyrite or “fool’s gold” among the samples and noted that the chemical breakdown of pyrite produces acids that in turn release CO2 from surrounding minerals.

They realized the fresh rock’s weathering processes, aided by the acid release by surrounding pyrite, produced more carbon than was estimated previously. This led researchers to consider the worldwide consequences of CO2 release brought on by the formation of major mountain ranges about 60 million years ago during the Cenozoic period.

To further explore the link between releases of atmospheric CO2 from weathering rock the researchers looked at marine records of long-term carbon cycles.

Researcher Josh West treks through a valley in Peru in search of evidence of chemical weathering of rocks as they erode. (Photo/courtesy of Mark Torres

Researcher Josh West treks through a valley in Peru in search of evidence of chemical weathering of rocks as they erode. (Mark Torres)

With this information, they were then able to reconstruct the balance between the discharge of CO2 into the atmosphere and absorption of the greenhouse gas from the production of fresh rocks brought on by the uplift of the Earth’s surface during the formation of large mountain ranges.

They found that weathering rock might have played a rather significant, but until now, unseen role in regulating the amount of carbon dioxide released into the atmosphere over the last 60 or so million years.

Lately, a lot of attention has focused on the harm caused to Earth’s climate by increased human-generated atmospheric carbon dioxide, but  the researchers who conducted the US/China study say Earth’s natural geologic system has kept things in balance for millions of years.

Happy Pi Day!

Posted March 14th, 2014 at 6:51 pm (UTC+0)
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Pi Symbol (MarianSigler via Wikimedia Commons)

Pi Symbol (MarianSigler via Wikimedia Commons)

Today, March 14, is a special day for those who are into mathematics or science.  It’s “Pi Day” or “Π Day”, the annual worldwide celebration of the ancient mathematical constant. It’s also the birthday of Albert Einstein who was born on March 14, 1879.

Pi Day has been commemorated in one way or another since physicist Larry Shaw organized the first celebration back on March 14, 1988, while working at a San Francisco museum called the Exploratorium.

Pi, a letter in the Greek alphabet, stands for the ratio of a circle’s circumference to its diameter. Rounded out, it is equal to approximately 3.14.

Historians have tracked the use of a constant ratio in making mathematical calculations as far back as the ancient Babylonians and Egyptians about 4,000 years ago.

In calculating the area of a circle, the ancient Babylonians used a formula that took three times the square of its radius. Some of these calculations set pi to equal 3 and while others have it as 3.125.

According to an ancient Egyptian papyrus, the builders of the Great Pyramids calculated the area of a circle with a formula that set the estimated value of pi as 3.1605.

It's a Pi Pie, created at Delft University of Technology in the Netherlands (Wikimedia Commons)

It’s a Pi Pie, created at Delft University of Technology in the Netherlands (Wikimedia Commons)

It wasn’t until the ancient Greek mathematician Archimedes approximated the area of a circle by using the Pythagorean Theorem that pi was first calculated. He determined pi was equal to a number between 3 1/7 (3.14285714) and 3 10/71 (3.14084507).

Historians have also pointed to calculations made by Zu Chongzhi, a brilliant Chinese mathematician and astronomer who lived about 200 to 300 years before Archimedes. Not much is known about Zu Chongzhi, books of his works have been lost, but he was said to have calculated the value of the ratio of the circumference of a circle to a diameter as 355/113 or approximately 3.14159292.

The use of the Greek letter π to signify the ratio of the circumference of a circle to its diameter was introduced in 1706, by Welsh mathematician William Jones, a close friend of Sir Isaac Newton.

Part of pi’s charm and mystique comes from the fact that it’s a number that can never be fully calculated to an exact value, because it goes on and on indefinitely without repeating or establishing any kind of regular pattern.

Over the centuries, mathematicians, scientists and others have enjoyed the challenge of trying to calculate π to as far of a decimal point as possible.

The current world’s record for calculating pi was set on December 28, 2013, by math enthusiasts and computer scientists Alexander J. Yee of the US and Shigeru Kondo of Japan. The two, using a computer they built, calculated pi to 12.1 trillion digits past the decimal point.

Albert Einstein circa 1947 (Photo: Library of Congress via Wikimedia Commons)

Happy Birthday Albert Einstein! (Library of Congress via Wikimedia Commons)

March 14 is an extra-special day in Princeton, New Jersey. Not only is it Pi Day, but they also celebrate the birth of a famous former resident, physicist and creator of the theories of relativity, Albert Einstein who lived and worked there for over 21 years.

In 1933, as Adolf Hitler and the Nazis were rising to power in Germany, Einstein, who was Jewish, fled his homeland  and settled in Princeton to work at the Institute for Advanced Study.

This year, Pi Day/Albert Einstein’s Birthday in Princeton is a 3-day celebration featuring a Pizza Pi “Top Chef” competition, an Albert Einstein lookalike contest and a Rubik’s Cube demonstration.

So whether it’s a gathering of friends enjoying a Pi Pie, participating in pie-throwing contests, or taking part in competitions to calculate pi to the largest decimal place, have fun! After all, Pi Day only comes once a year.

Are Oceans of Water Hiding Beneath Earth’s Surface?

Posted March 12th, 2014 at 6:32 pm (UTC+0)
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Photomicrograph of a grown ringwoodite blue crystal (Jasperox via Wikimedia Commons)

Photomicrograph of a man-grown ringwoodite blue crystal (Jasperox via Wikimedia Commons)

Scientists have discovered the first-ever earthly sample of a water-rich mineral they say provides new proof that there are vast oceans of water deep beneath the Earth’s surface.

The team, led by Graham Pearson from Canada’s University of Alberta, found a mineral called ringwoodite in a sample of rock taken from a Brazilian riverbed. Ringwoodite is a form of the gem-quality mineral peridot. Scientists believe there’s a sizable amount of peridot in part of Earth’s mantle called the transition zone, a high-pressure area located between the lower and upper mantle.

While ringwoodite has been found in meteorites, it hadn’t been previously detected in earthen samples. Its color can range from deep blue to red, violet, or it can even be colorless. Scientists have not been able to do the kind of research to locate ringwoodite because of the depths that would be involved in searching for and retrieving the mineral from its theorized location. The sample of ringwoodite found by the research team was designated a water-rich mineral after the scientists conducted an analysis that indicated that 1.5 percent of its total weight is water.

Researchers said the presence of this water confirms the theories that there are vast bodies of water being held somewhere between 410 and 660 kilometers below the surface of the Earth.

“This sample really provides extremely strong confirmation that there are local wet spots deep in the Earth in this area,” said Pearson. “That particular zone in the Earth, the transition zone, might have as much water as all the world’s oceans put together.”

Graham Pearson holds a diamond that contains the water-rich mineral "ringwoodite" (Richard Siemens - University of Alberta)

Graham Pearson holds a diamond that contains the water-rich mineral “ringwoodite” (Richard Siemens – University of Alberta)

Pearson said that their discovery almost didn’t happen since he and his team were originally looking for another mineral when they first obtained a little hunk of what they referred to as a “three-millimeter-wide, dirty-looking, commercially worthless brown diamond” in 2009. They didn’t spot the ringwoodite until they happened to dig beneath the diamond’s surface.

“It’s so small, this inclusion, it’s extremely difficult to find, never mind work on,” Pearson said, “so it was a bit of a piece of luck, this discovery, as are many scientific discoveries.”

The brown diamond sample Pearson’s team worked with was found in shallow river gravels by Brazilian miners in 2008. The scientists believe the diamond made it to Earth’s surface via a volcanic rock called kimberlite, which has been known to contain diamonds.  Formation of kimberlite takes place deep within the Earth’s mantle and is considered to be one of the deepest of all volcanic rocks.

The research team analyzed their sample of ringwoodite for several years. Among the techniques that were used to confirm the find were Raman and infrared spectroscopy as well as X-ray diffraction.  The team measured the water content of the mineral at Pearson’s Arctic Resources Geochemistry Laboratory at the University of Alberta.

Scientists have debated the structure of Earth’s transition zone; some say the region of the mantle is full of water, while others insist is dry.

(University of Alberta)

(University of Alberta)

Pearson and his team say being able to provide some proof that water does exists deep within the Earth will provide insight to those who study volcanism as well as plate tectonics.

“One of the reasons the Earth is such a dynamic planet is the presence of some water in its interior,” Pearson said. “Water changes everything about the way a planet works.”

The Pearson team’s research and findings are featured in Nature.

Scientists Identify Four New Ozone Depleting Gases in Atmosphere

Posted March 10th, 2014 at 6:46 pm (UTC+0)
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The false-color view of total ozone over the Antarctic pole (l) and Arctic pole (r) on March 6, 2014. The purple and blue colors are where there is the least ozone, and the yellows and reds are where there is more ozone. (NASA)

The false-color view of total ozone over the Antarctic pole (l) and Arctic pole (r) on March 6, 2014. The purple and blue colors are where there is the least ozone, and the yellows and reds are where there is more ozone. (NASA)

Scientists have identified four new man-made gases in the atmosphere that they say are helping to destroy Earth’s protective ozone layer.

Writing in Nature Geoscience, the researchers said that there are about 74,000,000 kilograms of three newly identified chlorofluorocarbons (CFCs) – compounds that only contain the atoms of carbon, fluorine and chlorine – and one new hydrochlorofluorocarbons (HCFC) – hydrogen, carbon, fluorine and chlorine – that have been released into our atmosphere.

The ozone layer, located between the upper troposphere and lower stratosphere, contains a high concentration of an inorganic compound called ozone or trioxygen in the atmosphere.  The ozone layer provides all life on Earth with protection from the harmful effects of the Sun’s radiation.

Model of a Chloroflurocarbon (CFC) molecule (NASA)

Model of a Chloroflurocarbon (CFC) molecule (NASA)

The gasses were identified by the group of scientists as CFC-112 (Tetrachloro-1, 2 – difluoroethane or Freon-112), CFC-112a (Tetrachloro-1, 1 – difluoroethane or Freon-112a), CFC-113a (1, 1, 1 – Trichloro – 2, 2, 2 – trifluoroethane or Freon-113a) and HCFC-133a (Monochlorotrifluoroethane).

The HCFCs are a group of man-made gases that were developed to replace CFC gases as refrigerants and aerosol propellants.  The production of HCFCs grew in the 1980s after nations agreed to phase out the use of CFCs.

While they were considered to be less harmful to the environment than CFCs, HCFCs sometimes referred to as “super greenhouse gases” are also very potent greenhouse gases, despite being in very low concentrations in the atmosphere.

The researchers were able to make their findings by comparing samples of today’s air with air that has been trapped within polar “firn snow”, or the accumulation of snow leftover from previous years, as well as unpolluted air that was sampled between 1978 and 2012 in Tasmania.  The scientists say the polar “firn snow” provided them with a natural archive of the atmosphere that dates back to about a century ago.

Measurements taken by the scientists indicated that all four of the new ozone layer-destroying gases have been released into the atmosphere recently but two them are amassing greatly.

The researchers said that the increase in emissions of the CFCs they studied have not been observed with any other CFC gases since the 1990s when stricter controls were introduced. But they do add that the current emissions are nowhere near the 1980s when the discharge of CFCs was at their peak with around 100,000,000 kilograms of the gases released each year.

“Our research has shown four gases that were not around in the atmosphere at all until the 1960s which suggests they are man-made,” said the study’s lead researcher  Johannes Laube from University of East Anglia..

The ozone cycle (Wikimedia Commons)

The ozone cycle (Wikimedia Commons)

CFC compounds have been identified as the key source of the hole in the ozone layer over Antarctica.

In order to protect the ozone layer, a number of nations around the world signed or ratified the Montreal Protocol on Substances that Deplete the Ozone Layer in 1987 and the agreement went into effect in 1989.  The international agreement sought to reduce and eventually phase out the use of CFCs by 2010.

Many consider the Montreal Protocol to be one of the most successful international agreements ever reached. The atmospheric concentrations of the most harmful CFCs have leveled off or at least have been decreased as a result, but there are various loopholes in the legislation that still allow usage of the CFCs for exempted purposes.

“The identification of these four new gases is very worrying as they will contribute to the destruction of the ozone layer,” said Laube. “We don’t know where the new gases are being emitted from and this should be investigated. Possible sources include feedstock chemicals for insecticide production and solvents for cleaning electronic components.”

Laube said that even if CFC emissions were to stop immediately, their presence would still be detected for many decades to come.

Hubble Watches and Records Rare Asteroid Disintegration

Posted March 7th, 2014 at 7:29 pm (UTC+0)
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This series of Hubble Space Telescope images reveals the breakup of an asteroid over a period of several months starting in late 2013. The largest fragments are up to 180 meters in radius. (NASA, ESA, D. Jewitt/UCLA)

This series of Hubble Space Telescope images reveals the breakup of an asteroid over a period of several months starting in late 2013. (NASA, ESA, D. Jewitt/UCLA)

NASA’s Hubble Space Telescope has captured some amazing and breathtaking images since it began scanning the cosmos in 1990.  But, from late last year into early this year, the space telescope was able to capture and record something that, until now, had never been seen before; the breakup of an asteroid located in the asteroid belt between Mars and Jupiter.

Sure, many astronomers have been able to watch comets break apart as they come close to the sun, but they’re much more fragile than asteroids.  Comets, which are basically dirty snowballs, are made mostly of ice and dust.  Asteroids, on the other hand, are chunks of solid rock made of more durable material such as clay, silicate and nickel-iron.  So asteroids are less likely to simply break apart than comets.

“This is a rock, and seeing it fall apart before our eyes is pretty amazing,” said David Jewitt of the University of California at Los Angeles, who led the astronomical forensics investigation.

Designated P/2013 R3, by the International Astronomical Union (IAU), the disintegrating asteroid, was first spotted on September 15, 2013 as an unusual and fuzzy-looking object by astronomers with the Catalina and Pan STARRS sky surveys located in Tucson, Arizona and Maui, Hawaii respectively.

Following-up on these observations about two weeks later scientists with the W. M. Keck Observatory, located atop Mauna Kea, a dormant volcano located on the island of Hawaii, spotted three astronomical bodies moving together and were enveloped in a cloud of dust that was as big as the diameter of Earth.

“The Keck Observatory showed us this thing was worth looking at with Hubble,” said Jewitt. “With its superior resolution, space telescope observations soon showed there were really 10 embedded objects, each with comet-like dust tails. The four largest rocky fragments are up to 400 yards (365.76 meters) in diameter, about four times the length of a (American) football field.”

The Hubble provided data that indicated that the asteroid fragments slowly wandered away from each other at a speed of nearly 1.6093 kilometers-per-hour.

Astronomers said that the P/2013 R3 actually began breaking apart sometime early last year, but newer images of the broken-up asteroid have shown it to split into even more pieces since.

The breakup of asteroid P/2013 R3 (NASA/ESA Hubble Space Telescope)

The break-up of the asteroid, according to those who’ve been observing it, is not likely due to it colliding with another asteroid, because if it had the fragmentation would have been quicker and much more violent compared to its slow and gradual destruction.

The astronomers also noted that such a smash-up of two asteroids would produce debris that would probably travel much faster than what they had observed.

They also don’t think the asteroid became unglued and fell apart because of the pressure of its interior ices warming and vaporizing.

So, this left the astronomers to consider something that’s been discussed before, but never directly observed.  Perhaps the asteroid disintegrated because of what was described as a subtle effect of sunlight, which gradually speeds up the asteroid’s rotation rate.  As the asteroid continues to spin faster and faster, centrifugal force kicks and causes the asteroid to gradually pull itself apart.

For this self-destruct scenario to work, astronomers say that the P/2013 R3 had to have had a weak and fractured interior that was most likely caused by a number of non-destructive collisions with other asteroids.

Scientists are now figuring that most small asteroids in our solar system were probably severely damaged in this way. The break-up of the P/2013 R3, they said, was most likely due to such an asteroid to asteroid collision that took place sometime within the last billion years.

The asteroid belt (shown in white) is located between the orbits of Mars and Jupiter. Other groups of asteroids (in green) (Wikimedia Commons)

The asteroid belt (shown in white) is located between the orbits of Mars and Jupiter. Other groups of asteroids (in green) (Wikimedia Commons)

Looking back at another occasion when they saw six tails springing from asteroid P/2013 P5 along with what they’ve observed with P/2013 R3, astronomers said that they are finding more proof that the pressure of sunlight could very well be the primary factor that has caused our solar system’s small asteroids, those less than 1.6 kilometers across, to disintegrate.

Those following the destruction of P/2013 R3 figure that the remaining debris from the now broken-up asteroid probably weighs about 181,437 metric tons and will mostly likely become a source of future meteoroids.

Astronomers’ figure that most of the remaining debris will eventually plunge into the sun, but a small amount of what’s left of asteroid P/2013 R3 may someday provide a spectacular show for us as they blaze across the sky as meteors.

Have Saturated Fats Been Unjustly Vilified?

Posted March 5th, 2014 at 11:32 pm (UTC+0)
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A big juicy hamburger with bacon, egg and all the trimings (Marshall Astor via Flickr/Creative Commons)

A big juicy hamburger with bacon, egg and all the trimmings (Marshall Astor via Flickr/Creative Commons)

You’d really love to eat a nice juicy hamburger, wouldn’t you?

But maybe you resist the temptation because you’re watching your weight and your doctor wants you to cut down on saturated fats in order to prevent heart disease.

We’re not recommending that you go ahead and splurge on that burger, but a US cardiovascular research scientist says saturated fats have been unfairly vilified and points to carbs as the real health culprit.

Dr. James DiNicolantonio says refined carbohydrates—and not saturated fats—are to blame for the current surge in obesity and diabetes that leads to heart disease.

Writing in the British Medical Journal’s Open Heart cardiology journal, DiNicolantonio says the long-held advice to switch from saturated fats to foods with carbohydrates or omega 6-rich polyunsaturated fats is based on flawed and incomplete data that dates back to 1952.

Starchy foods like breads, pasta and rice are rich in refined carbohydrates (Wikimedia Commons)

Starchy foods like breads, pasta and rice are rich in refined carbohydrates. (Wikimedia Commons)

The 1952 study linked a high-fat diet to deaths from heart disease. DiNicolantonio says the author of that study reached his conclusions based on data from only six out of 22 countries researched and chose to ignore the data from the other 16 nations, because it didn’t match up with the researcher’s hypothesis.

Later analysis of the research data that included all 22 nations actually disproved the study’s conclusions, he says.

The removal of saturated fats from our daily diets got a big boost after US President Dwight D. Eisenhower, who was 64 then, had a heart attack in 1955.

That incident help foster the belief that since saturated fats increase a person’s total cholesterol, then they must also increase the risk of heart disease. Therefore cutting back on saturated fat intake would naturally curb obesity, diabetes and metabolic syndrome.

While he does agree that a low fat-diet may help lower LDL, or “bad” cholesterol, DiNicolantonio points out that there are two types of this bad cholesterol to consider.

He suggests that switching to foods rich with refined carbs could increase one type of cholesterol called “pattern B (small density) LDL,” which can be more dangerous to heart health than “pattern A (large buoyant) LDL.” This, he says, would create a more harmful overall lipid profile, which is the level of compounds in the blood that includes waxes, oils, sterols, triglycerides, phosphatides, and phospholipids.

DiNicolantonio says there are other studies that have shown following a diet low in carbohydrates is better for weight loss and leads to a more improved lipid profile than following a low-fat diet. He also points out that large observational studies have not found any irrefutable proof that a low-fat diet cuts the risk of cardiovascular disease.

(Open Clipart)

(Open Clipart)

Several of the dietary guidelines developed since 1952 also recommend not only a cut in saturated fats, but also an increase in the intake of polyunsaturated fat.

DiNicolantio says an analysis of published trial data has shown that simply replacing saturated fats and trans-fatty acids with foods containing omega 6 fatty acids, without a matching rise in omega 3 fatty acids, seems to increase the risk of death from coronary heart and cardiovascular diseases.

“We need a public health campaign as strong as the one we had in the 70s and 80s demonizing saturated fats, to say that we got it wrong,” said DiNicolantonio.

He considers a diet low in refined carbohydrates, sugars and processed foods to be the best for maintaining good heart health.

He also recommends that anyone who’s had a heart attack not replace saturated fatty foods with those that contain refined carbs or omega 6 fatty acids, especially those that are found in processed vegetable oils that are comprised of large amounts of corn or safflower oil.

Report Provides Further Evidence People Cause Climate Change

Posted March 3rd, 2014 at 7:47 pm (UTC+0)
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Cover page to new climate change report (Royal  Society/US National Academy of Science)

Cover page to new climate change report (Royal Society/US National Academy of Science)

New evidence suggests climate change is human caused and that if the release of greenhouse gases continues unabated, changes to the world’s climate will greatly exceed those that have taken place so far.

The new joint report from the US National Academy of Sciences and the Royal Society, the national science academy of the UK, is called Climate Change: Evidence and Causes.  It predicts Earth’s temperature will rise between 5-to-9 degrees Fahrenheit by the end of the century.

“As two of the world’s leading scientific bodies, we feel a responsibility to evaluate and explain what is known about climate change, at least the physical side of it, to concerned citizens, educators, decision makers and leaders, and to advance public dialogue about how to respond to the threats of climate change,” said the USNAS President Ralph  Cicerone.

Even if the release of greenhouse gases were stop immediately temperatures would continue to rise, according to the report.

Arctic ice melt impacts nature (Agrant141 via Wikimedia Commons)

Arctic ice melt impacts nature (Agrant141 via Wikimedia Commons)

“If greenhouse gas emissions were to suddenly stop, the earth would not cool to preindustrial levels for thousands of years,” said Inez Fung, the U.S. lead author of the report from the University of California, Berkeley. “The actions of today have long-term effects. Stopping emissions now doesn’t mean we can remove the carbon dioxide that is already in the atmosphere. The accumulation of CO2 in the atmosphere causes continued rises in temperatures and sea levels.”

The report is written in easy-to-understand English, addresses 20 important issues in a question-and-answer format, and explains which characteristics of climate change are well established and documented as well as those that aren’t which require further investigation.

“Climate change is a dividing issue of our times,” said Paul Nurse, head of the Royal Society. “Policy decisions are made on the world stage. This is a simple but authoritative account of the major issues of climate change. It’s a reliable guide to the science – a guide that’s necessary for an informed debate.”

This visualization shows a running five-year average global temperature, as compared to a baseline average global temperature from 1951-1980. (NASA GISS)

This visualization shows a running five-year average global temperature, as compared to a baseline average global temperature from 1951-1980. (NASA)

According to the report, current atmospheric C02 levels have risen to a level that hasn’t been seen in about 800,000 years. A review of observational data dating back to the mid-19th century has shown a definite long-term warming trend. Researchers have found that, since 1900, Earth’s average surface air temperature has increased by about 1.4 degrees Fahrenheit and that much of that rise took place in the mid-1970s.

Measurements made by the American and British teams that prepared the report show the increase of atmospheric C02 has been mostly caused by combustion of fossil fuels and not due to naturally occurring phenomena such as changes in the sun’s output as some have suggested.

Two people brave the extreme cold temperatures in Chicago (wind chills of -40 degrees F) on 1/6/14 when a whirlpool of frigid dense air known as a "polar vortex" descended Monday into much of the U.S. Some scientists suggest the extreme winter weather is a result of climate change. (AP Photo/Charles Rex Arbogast)

Two people brave the extreme temperatures in Chicago on Jan. 6, 2014, when a “polar vortex” descended on much of the U.S.(AP)

The reduction in Arctic sea ice, a rise in ocean temperatures as well as changes in nature like the movement of temperature-sensitive species of fish, mammals, insects toward the poles, provide irrefutable evidence of planetary-scale warming, said the report authors.

A number of people living along the East Coast have questioned climate change after being hit with extreme weather conditions this winter brought on by polar vortices. Even with spring only a couple of weeks away, the mid-Atlantic region of the US is being hit today by a major winter storm that has brought with it very cold temperatures as well as treacherous accumulations of snow and ice.

But Fung suggests that climate change may be responsible for the harsh winter weather as well as other forms of extreme weather such as record heat, drought or rainfall.

“A warmer atmosphere can hold more moisture so when it rains, there’s more rain,” she said. “Rainfall will be more intense. Heat waves will become more frequent. We expect droughts, when they occur, will be more severe. There will always be cold nights and cold days in this warming trend, but they will be rarer and rarer.”

NASA, ESA Ramp Up Planet-hunting Missions

Posted February 28th, 2014 at 8:33 pm (UTC+0)
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Artist concept depicts multiple-transiting planet systems - stars with more than one planet orbiting it - that have been discovered recently by NASA's Kepler mission. )(NASA)

Artist conception of multiple transiting planet systems – stars with more than one planet orbiting it – discovered recently by NASA’s Kepler mission. (NASA)

NASA’s planet-hunting Kepler mission stirred up excitement this week when mission officials announced they’d hit the proverbial jackpot – discovering and confirming a record 715 new planets orbiting 305 stars.

Nearly 95 percent of these newly found planets are smaller than Neptune, but four are about 2.5 times bigger than Earth and are located within what scientists call the habitable zone, meaning they are just the right distance from their parent stars for liquid surface water, an important element of life, to form.

Artist rendering of NASA's TESS - Transiting Exoplanet Survey Satellite in space (NASA)

Artist rendering of NASA’s TESS – Transiting Exoplanet Survey Satellite in space (NASA)

Even though the spacecraft was hobbled last summer after experiencing problems with accurately pointing its telescope, Kepler accumulated so much observational data during its operational time that astronomers will have plenty of information to wade through which could lead to possible new discoveries.

Meantime, NASA and the European Space Agency (ESA) aren’t wasting any time preparing the next generation of planet-hunting missions.

NASA plans a 2017 launch of its Transiting Exoplanet Survey Satellite (TESS). The TESS space telescope, which will be equipped with an array of telescopes, will conduct an all-sky survey.

TESS will be on the lookout for a variety of transiting exoplanets – planets that are detected when their host stars dim as they pass – that orbit the nearest and the brightest stars the sky.

TESS will look for and identify gas giant planets as well as Earth-like planets orbiting within their host stars’ habitable zone.

WFIRST-AFTA (Wide Field Infrared Survey Telescope - Astrophysics Focused Telescope Assets) rendering of on-orbit situation. (Mark Melton, NASA/GSFC)

Artist rendering of WFIRST – Wide Field Infrared Survey Telescope (NASA)

Sometime in the early 2020s, NASA plans to launch an ambitious mission called The Wide Field Infrared Survey Telescope (WFIRST).

The WFIRST is an infrared space observatory that will not only join the search for potentially habitable extrasolar planets, but will help scientists learn more about the nature of dark energy and why the universe is rapidly expanding.

Scientists are also hoping WFIRST will help them learn more about how stars, galaxies and black holes form and evolve.

Just last week, ESA announced it has green-lighted an initial six-year mission that will join the search for alien planets orbiting within neighboring star systems.

The Planetary Transits and Oscillations of stars (PLATO), a space-based observatory, will launch on a Soyuz rocket from Europe’s Spaceport in Kourou, French Guiana, sometime between 2022 and 2024.

An artist's drawing of one of ESA's proposed PLATO space telescopes - notice the bank of 34 telescopes.(© ESA)

An artist’s drawing of one of ESA’s proposed PLATO space telescopes. Notice the bank of 34 telescopes.(© ESA)

PLATO will feature 34 separate telescopes  searching for planets among up to a million stars.

ESA said PLATO will observe and monitor stars that are relatively nearby and will look for planets, especially those that are Earth-like and super-Earth-like, that transit in front of them.

Along with looking for planets located in a star’s habitable zone, PLATO will also examine seismic activity in a discovered planet’s host star enabling scientists to learn more factors such as its mass, radius and age.

ESA officials are also planning to couple various measurements made by PLATO along with ground-based radial velocity observations. Joining data from these two sources should help scientists calculate an exoplanet’s mass and radius so they can get an idea its composition.

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