Excerpt from mashable.com Thanks to a rare, severe geomagnetic storm, the Northern Lights may be visible on Tuesday night in areas far to the south of its typical home in the Arctic. The northern tier of the U.S., from Washington State to Michiga...
Tag: press (page 2 of 16)
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| Minnesota Twins (not the baseball team) James & James, whose similar stories defy chance and coincidence. |
Excerpt from people.com
May 7th, 1979
One of science's so far uncrackable mysteries is the comparative impact of heredity vs. environment. An obvious experimental method would be to raise identical twins separately, but that could hardly be done with humans. So for the last 10 years University of Minnesota psychologist Thomas Bouchard, 41, has been studying twins under less than ideal, lab-controlled conditions—until, eureka, he ran into the stuff of social scientists' dreams. Identical twin males, who had been separated by adoption at three weeks, suddenly rediscovered each other in Ohio at age 39.
Within two weeks after reading about them in the press, Dr. Bouchard had the twins in his Minneapolis lab for tests. At the outset of his investigation the psychologist said, "I think there are going to be all kinds of differences that will surprise even the twins." But what was immediately apparent were eerie similarities that left even Bouchard "flabbergasted."
Curiously, both had been christened James by their adoptive parents, the Jess Lewises of Lima and the Ernest Springers of Piqua, 40 miles away. As schoolboys, both enjoyed math and carpentry—but hated spelling. Both pursued similar adult occupations: Lewis is a security guard at a steel mill, and Springer was a deputy sheriff (though he is now a clerk for a power company). Both married women named Linda, only to divorce and remarry—each a woman named Betty. Both have sons: James Alan Lewis and James Allan Springer.
The two men shared one other fact in common. As Jim Springer put it, "I always felt an emptiness." Neither the Springers nor the Lewises ever met the 15-year-old (unwed) mother of their sons, and both couples were told that their adoptive child had a twin who died at birth. Then one day, when Jim Lewis was 16 months old, his mother visited the Miami County courthouse to settle the adoption paperwork, and an official remarked offhandedly, "They named the other little boy 'Jim' too."
For 37 years that hint tugged at Mrs. Lewis, who occasionally urged her son to find out if it was true. Finally, last Thanksgiving, he agreed to search—though he says he doesn't know why. Jim Lewis wrote the probate court, which had a record of the adoption, and contacted the Springer parents in Piqua. "I came home one day," Lewis recounts, "and had this message to call 'Jim Springer.' " When he phoned Springer, Lewis blurted out: "Are you my brother?" "Yup," Springer replied. Four days later, last Feb. 9, Lewis drove to meet his twin for an emotional reunion.
Dr. Bouchard offered expenses and a small honorarium to get them to Minneapolis for a week of extensive physical and psychological tests. He wanted to begin as soon as possible to preclude their reminiscing together too long and thus "contaminating" the evidence. Though not the first such separated twins—the records show 19 previous sets in the U.S. among some 75 worldwide—Lewis and Springer were believed to have been apart by far the longest.
The detailed results of Bouchard's textbook case will be revealed to the twins themselves, but to protect their privacy will be buried among other data in the professor's book on differential psychology now in progress. There has been one development that may leave the twins still puzzling over heredity and environment. On Feb. 28 Jim Lewis, having divorced his second wife, Betty, married a woman named Sandy Jacobs. Betty and Jim Springer were present, with Jim serving as his newfound brother's best man.
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| Artist's impression of Gliese 581d, a controversial exoplanet that may exist only 20 light-years from Earth. |
Excerpt from news.discovery.com
Despite having discovered nearly 2,000 alien worlds beyond our solar system, the profound search for exoplanets — a quest focused on finding a true Earth analog — is still in its infancy. It is therefore not surprising that some exoplanet discoveries aren’t discoveries at all; they are in fact just noise in astronomical data sets.
But when disproving the existence of extrasolar planets that have some characteristics similar to Earth, we need to take more care during the analyses of these data, argue astronomers from Queen Mary, University of London and the University of Hertfordshire.
In a paper published by the journal Science last week, the researchers focus on the first exoplanet discovered to orbit a nearby star within its habitable zone.
Revealed in 2009, Gliese 581d hit the headlines as a “super-Earth” that had the potential to support liquid water on its possibly rocky surface. With a mass of around 7 times that of Earth, Gliese 581d would be twice as big with a surface gravity around twice that of Earth. Though extreme, it’s not such a stretch of the imagination that such a world, if it is proven to possess an atmosphere and liquid ocean, that life could take hold.
And the hunt for life-giving alien worlds is, of course, the central motivation for exoplanetary studies.
But the exoplanet signal has been called into doubt.
Gliese 581d’s star, Gliese 581, is a small red dwarf around 20 light-years away. Red dwarfs are known to be tempestuous little stars, often generating violent flaring outbursts and peppered in dark features called starspots. To detect the exoplanet, astronomers measured the very slight frequency shift (Doppler shift) of light from the star — as the world orbits, it exerts a tiny gravitational “tug”, causing the star to wobble. When this periodic wobble is detected, through an astronomical technique known as the “radial velocity method,” a planet may be revealed.
Last year, however, in a publication headed by astronomers at The Pennsylvania State University, astronomers pointed to the star’s activity as an interfering factor that may have imitated the signal from an orbiting planet when in fact, it was just noisy data.
But this conclusion was premature, argues Guillem Anglada-Escudé, of Queen Mary, saying that “one needs to be more careful with these kind of claims.”
“The existence, or not, of GJ 581d is significant because it was the first Earth-like planet discovered in the ‘Goldilocks’-zone around another star and it is a benchmark case for the Doppler technique,” said Anglada-Escudé in a university press release. “There are always discussions among scientists about the ways we interpret data but I’m confident that GJ 581d has been in orbit around Gliese 581 all along. In any case, the strength of their statement was way too strong. If the way to treat the data had been right, then some planet search projects at several ground-based observatories would need to be significantly revised as they are all aiming to detect even smaller planets.”
The upshot is that this new paper challenges the statistical technique used in 2014 to account for the signal being stellar noise — focusing around the presence of starspots in Gliese 581′s photosphere.
Gliese 581d isn’t the only possible exoplanet that exists around that star — controversy has also been created by another, potentially habitable exoplanet called Gliese 581g. Also originally detected through the wobble of the star, this 3-4 Earth mass world was found to also be in orbit within the habitable zone. But its existence has been the focus of several studies supporting and discounting its presence. Gliese 581 is also home to 3 other confirmed exoplanets, Gliese 581e, b and c.
Currently, observational data suggests Gliese 581g was just noise, but as the continuing debate about Gliese 581d is proving, this is one controversy that will likely keep on rumbling in the scientific journals for some time.
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| Astronomers in Brazil have discovered a cluster of stars forming at the edge of the Milky Way, according to a press release from the Royal Astronomical Society. |
Excerpt from news.discovery.com
This is unusual because it was believed that stars generally take form closer to the center of our spiral-shaped galaxy, rather than from its swirling, spiral arms, which are thousands of light-years away. These two clusters of stars — named Camargo 438 and 439 — were seen in a cloud at the galaxy’s outskirts.
Denilso Camargo, an astronomer at the Federal University of Rio Grande do Sul in Porto Alegre, Brazil, led a team that analyzed data from NASA’s orbiting Wide-Field Infrared Survey Explorer (WISE) observatory. They zeroed in on dense clumps of gas in so-called giant molecular clouds(GMCs) that are known to generate stars. GMCs are mainly located in the inner part of the galactic disc.
The new star clusters lie about 16,000 light-years away from the main disk of the Milky Way galaxy. How did they form there? The scientists aren’t yet sure but Camargo theorizes that one of two scenarios could have led to the stars’ formation.
In the first scenario, called the “chimney model,” supernovas could have flung the gas and dust that formed the cloud out of the Milky Way. Another explanation is the material could have drifted in from outside the galaxy.
“Our work shows that the space around the Galaxy is a lot less empty that we thought,” said Camargo. “The new clusters of stars are truly exotic.”
Camargo’s team published their results in the journal Monthly
Ceres Excerpt from cnet.com It's a real-life mystery cliffhanger. We've come up with a list of possible reasons a large crater on the biggest object in the asteroid belt looks lit up like a Christmas tree. We could be approachin...
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| This infrared image shows the dust ring around the nearby star HR 4796A in the southern constellation of Centaurus. |
Excerpt from news.discovery.com
By Ian O'Neill
A new instrument attached to one of the most powerful telescopes in the world has been switched on and acquired its ‘first light’ images of alien star systems and Saturn’s moon Titan.
The Spectro-Polarimetric High-contrast Exoplanet REsearch (or SPHIRES) instrument has been recently installed at the ESO’s Very Large Telescope’s already impressive suite of sophisticated instrumentation. The VLT is located in the ultra-dry high-altitude climes of the Atacama Desert in Chile.
In the observation above, an ‘Eye of Sauron‘-like dust ring surrounding the star HR 4796A in the southern constellation of Centaurus, a testament to the sheer power of the multiple technique SPHIRES will use to acquire precision views of directly-imaged exoplanets.
The biggest problem with trying to directly image a world orbiting close to its parent star is that of glare; stars are many magnitudes brighter that the reflected light from its orbiting exoplanet, so how the heck are you supposed to gain enough contrast between the bright star and exoplanet to resolve the two? The SPHIRES instrument is using a combination of three sophisticated techniques to remove a star’s glare and zero-in on its exoplanetary targets.
The first technique, known as adaptive optics, is employed by the VLT itself. By firing a laser into the Earth’s atmosphere during the observation, a gauge on the turbulence in the upper atmospheric gases can be measured and the effects of which can be removed from the imagery. Any blurriness caused by our thick atmosphere can be adjusted for.
Next up is a precision coronograph inside the instrument that blocks the light from the target star. By doing this, any glare can be removed and any exoplanet in orbit may be bright enough to spot.
But the third technique, which really teases out any exoplanet signal, is the detection of different polarizations of light from the star system. The polarization of infrared light being generated by the star and the infrared glow from the exoplanet are very subtle. SPHIRES can differentiate between the two, thereby further boosting the observation’s contrast.
“SPHERE is a very complex instrument. Thanks to the hard work of the many people who were involved in its design, construction and installation it has already exceeded our expectations. Wonderful!” said Jean-Luc Beuzit, of the Institut de Planétologie et d’Astrophysique de Grenoble, France and Principal Investigator of SPHERE, in an ESO press release.
The speed and sheer power of SPHIRES will be an obvious boon to astronomers zooming in on distant exoplanets, aiding our understanding of these strange new worlds.
By Ian O'Neill
A new instrument attached to one of the most powerful telescopes in the world has been switched on and acquired its ‘first light’ images of alien star systems and Saturn’s moon Titan.
The Spectro-Polarimetric High-contrast Exoplanet REsearch (or SPHIRES) instrument has been recently installed at the ESO’s Very Large Telescope’s already impressive suite of sophisticated instrumentation. The VLT is located in the ultra-dry high-altitude climes of the Atacama Desert in Chile.
In the observation above, an ‘Eye of Sauron‘-like dust ring surrounding the star HR 4796A in the southern constellation of Centaurus, a testament to the sheer power of the multiple technique SPHIRES will use to acquire precision views of directly-imaged exoplanets.
The biggest problem with trying to directly image a world orbiting close to its parent star is that of glare; stars are many magnitudes brighter that the reflected light from its orbiting exoplanet, so how the heck are you supposed to gain enough contrast between the bright star and exoplanet to resolve the two? The SPHIRES instrument is using a combination of three sophisticated techniques to remove a star’s glare and zero-in on its exoplanetary targets.
This infrared image of Saturn’s largest moon, Titan, was one of the first produced by the SPHERE instrument soon after it was installed on ESO’s Very Large Telescope in May 2014.
ESO
Next up is a precision coronograph inside the instrument that blocks the light from the target star. By doing this, any glare can be removed and any exoplanet in orbit may be bright enough to spot.
But the third technique, which really teases out any exoplanet signal, is the detection of different polarizations of light from the star system. The polarization of infrared light being generated by the star and the infrared glow from the exoplanet are very subtle. SPHIRES can differentiate between the two, thereby further boosting the observation’s contrast.
“SPHERE is a very complex instrument. Thanks to the hard work of the many people who were involved in its design, construction and installation it has already exceeded our expectations. Wonderful!” said Jean-Luc Beuzit, of the Institut de Planétologie et d’Astrophysique de Grenoble, France and Principal Investigator of SPHERE, in an ESO press release.
The speed and sheer power of SPHIRES will be an obvious boon to astronomers zooming in on distant exoplanets, aiding our understanding of these strange new worlds.
The star HR 7581 (Iota Sgr) was observed in SPHERE survey mode (parallel observation in the near infrared with the dual imaging camera and the integral field spectrograph ). A very low mass star, more than 4000 times fainter that its parent star, was discovered orbiting Iota Sgr at a tiny separation of 0.24". This is a vital demonstration of the power of SPHERE to image faint objects very close to bright ones.
ESO
Jerdon's BabblerExcerpt from techtimes.comJerdon's Babbler is a species of bird that was believed to be extinct until this species unexpectedly resurfaced in Myanmar. This brown and white bird is roughly the size of a house sparrow.The bird was last ...
| Titan |
Excerpt from mashable.com
In a world first, chemical engineers have taken a different look at a question astronomers and biologists have been pondering for decades: Does Saturn moon Titan host life?
Of course, Titan is way too hostile for life as we know it to eke out an existence — it is a frigid world awash with liquid methane and ethane and a noxious atmosphere devoid of any liquid water. But say if there is a different kind of biology, a life as we don't know it, thriving on the organic chemistry that is abundant on Titan's surface?
Normally, astrobiologists combine what we know about Earth's biosphere and astronomers zoom in on other stars containing exoplanets in the hope that some of those alien world have some similarities to Earth. By looking for small rocky exoplanets orbiting inside their star's habitable zones, we are basically looking for a "second Earth" where liquid water is at least possible. Where there's liquid water on Earth, there's inevitably life, so scientists seeking out alien life 'follow the water' in the hope of finding life with a similar terrestrial template on other planets.
Titan, however, does not fall into this category, it is about as un-Earth-like as you can get. So, chemical molecular dynamics expert Paulette Clancy and James Stevenson, a graduate student in chemical engineering, from Cornell University, Ithaca, New York, have looked at Titan in a different light and created a theoretical model of a methane-based, oxygen-free life form that could thrive in that environment.
There is no known template for this kind of life on Earth, but the researchers have studied what chemicals are in abundance on Titan and worked out how a very different kind of life could be sparked.
As a collaborator on the NASA/ESA Cassini-Huygens mission, Lunine, professor in the Physical Sciences in the College of Arts and Sciences’ Department of Astronomy, has been fascinated with the possibility of methane-based life existing on Titan for some time, so he joined forces with Clancy and Stevenson to see what this hypothetical life form might look like.
In their research published in the journal Science Advances on Feb. 27, Clancy and Stevenson focused on building a cell membrane "composed of small organic nitrogen compounds and capable of functioning in liquid methane temperatures of 292 degrees below zero (Fahrenheit; or 94 Kelvin)," writes a Cornell press release. On Earth, water-based molecules form phospholipid bilayer membranes that give cells structure, housing organic materials inside while remaining permeable. On Titan, liquid water isn't available to build these cell membranes.
"We're not biologists, and we're not astronomers, but we had the right tools," said Clancy, lead researcher of the study. "Perhaps it helped, because we didn't come in with any preconceptions about what should be in a membrane and what shouldn't. We just worked with the compounds that we knew were there and asked, 'If this was your palette, what can you make out of that?'"
The researchers were able to model the ideal cell that can do all the things that life can do (i.e. support metabolism and reproduction), but constructed it from nitrogen, carbon and hydrogen-based molecules that are known to exist in Titan's liquid methane seas. This chemical configuration gives this theoretical alien cell stability and flexibility in a similar manner to Earth life cells.
"The engineers named their theorized cell membrane an 'azotosome,' 'azote' being the French word for nitrogen. 'Liposome' comes from the Greek 'lipos' and 'soma' to mean 'lipid body;' by analogy, 'azotosome' means 'nitrogen body.'" — Cornell"Ours is the first concrete blueprint of life not as we know it," said lead author Stevenson, who also said that he was inspired, in part, by Isaac Asimov, who wrote the 1962 essay "Not as We Know It" about non-water-based life.
Having identified a possible type of cell membrane chemistry that functions in the Titan environment as a cell on Earth might, the next step is to model how such a hypothetical type of biology would function on Titan. In the long run, we might also be able to model what kinds of observable indicators we should look for that might reveal that alien biology's presence.
That way, should a mission be eventually sent to Titan's seas, sampling the chemical compounds in the soup of organics may reveal a biology of a very alien nature.
Scientists have been trying to know if life could exist on Titan, the largest moon of Saturn. According to scientists, there are possibilities that life could survive amidst methane-based lakes of Titan. After conducting many studies, they have found signs of life on Titan, but the scientists also said that life will not be like life on earth.
As per some scientific reports, Titan is the only object other than earth which has clear evidence of stable bodies of surface liquid. Like earth, the moon has mountains, islands, lakes and storms, but it doesn’t have oxygen, which is a major element to support life. It means that only oxygen-free and methane-based can exist on Titan.
According to lead researcher Paulette Clancy, “We didn’t come in with any preconceptions about what should be in a membrane and what shouldn’t. We just worked with the compounds that, we knew were there and asked, ‘If this was your palette, what can you make out of that”.
Clancy said although they are not biologists or astronomers, they had the right tools to find life on Saturn’s largest moon. Adding to that, the researchers didn’t know what should be in a membrane and what should be not. They worked with compounds and found that life can exist on Titan, but would be very different from earth’s life, Clancy added.
According to reports, the researchers had used a molecular dynamics method to know about Titan. They screened for suitable candidate compounds from methane for self-assembly into membrane-like structures. As per the researchers, the most promising compound they discovered was an acrylonitrile azotosome, which is present in the atmosphere of Titan.
As per the researchers, acrylonitrile has shown good stability and flexibility similar to that of phospholipid membranes on Earth. It means that the Saturn largest has atmosphere and conditions to support life in a different way than earth.
- See more at: http://perfscience.com/content/2141391-life-titan-would-be-different-earth#sthash.2Kqc3Ewf.dpuf
As per some scientific reports, Titan is the only object other than earth which has clear evidence of stable bodies of surface liquid. Like earth, the moon has mountains, islands, lakes and storms, but it doesn’t have oxygen, which is a major element to support life. It means that only oxygen-free and methane-based can exist on Titan.
According to lead researcher Paulette Clancy, “We didn’t come in with any preconceptions about what should be in a membrane and what shouldn’t. We just worked with the compounds that, we knew were there and asked, ‘If this was your palette, what can you make out of that”.
According to reports, the researchers had used a molecular dynamics method to know about Titan. They screened for suitable candidate compounds from methane for self-assembly into membrane-like structures. As per the researchers, the most promising compound they discovered was an acrylonitrile azotosome, which is present in the atmosphere of Titan.
As per the researchers, acrylonitrile has shown good stability and flexibility similar to that of phospholipid membranes on Earth. It means that the Saturn largest has atmosphere and conditions to support life in a different way than earth.
- See more at: http://perfscience.com/content/2141391-life-titan-would-be-different-earth#sthash.2Kqc3Ewf.dpuf
Excerpt from independent.co.uk
By Jordan Gaines Lewis
In neuroscience, food is something we call a “natural reward.” In order for us to survive as a species, things like eating, having sex and nurturing others must be pleasurable to the brain so that these behaviours are reinforced and repeated.
Evolution has resulted in the mesolimbic pathway, a brain system that deciphers these natural rewards for us. When we do something pleasurable, a bundle of neurons called the ventral tegmental area uses the neurotransmitter dopamine to signal to a part of the brain called the nucleus accumbens. The connection between the nucleus accumbens and our prefrontal cortex dictates our motor movement, such as deciding whether or not to taking another bite of that delicious chocolate cake. The prefrontal cortex also activates hormones that tell our body: “Hey, this cake is really good. And I’m going to remember that for the future.”Not all foods are equally rewarding, of course. Most of us prefer sweets over sour and bitter foods because, evolutionarily, our mesolimbic pathway reinforces that sweet things provide a healthy source of carbohydrates for our bodies. When our ancestors went scavenging for berries, for example, sour meant “not yet ripe,” while bitter meant “alert – poison!”
Fruit is one thing, but modern diets have taken on a life of their own. A decade ago, it was estimated that the average American consumed 22 teaspoons of added sugar per day, amounting to an extra 350 calories; it may well have risen since then. A few months ago, one expert suggested that the average Briton consumes 238 teaspoons of sugar each week.
Today, with convenience more important than ever in our food selections, it’s almost impossible to come across processed and prepared foods that don’t have added sugars for flavour, preservation, or both.
These added sugars are sneaky – and unbeknown to many of us, we’ve become hooked. In ways that drugs of abuse – such as nicotine, cocaine and heroin – hijack the brain’s reward pathway and make users dependent, increasing neuro-chemical and behavioural evidence suggests that sugar is addictive in the same way, too.
Sugar addiction is real
Anyone who knows me also knows that I have a huge sweet tooth. I always have. My friend and fellow graduate student Andrew is equally afflicted, and living in Hershey, Pennsylvania – the “Chocolate Capital of the World” – doesn’t help either of us. But Andrew is braver than I am. Last year, he gave up sweets for Lent. “The first few days are a little rough,” Andrew told me. “It almost feels like you’re detoxing from drugs. I found myself eating a lot of carbs to compensate for the lack of sugar.”There are four major components of addiction: bingeing, withdrawal, craving, and cross-sensitisation (the notion that one addictive substance predisposes someone to becoming addicted to another). All of these components have been observed in animal models of addiction – for sugar, as well as drugs of abuse.
A typical experiment goes like this: rats are deprived of food for 12 hours each day, then given 12 hours of access to a sugary solution and regular chow. After a month of following this daily pattern, rats display behaviours similar to those on drugs of abuse. They’ll binge on the sugar solution in a short period of time, much more than their regular food. They also show signs of anxiety and depression during the food deprivation period. Many sugar-treated rats who are later exposed to drugs, such as cocaine and opiates, demonstrate dependent behaviours towards the drugs compared to rats who did not consume sugar beforehand.
Like drugs, sugar spikes dopamine release in the nucleus accumbens. Over the long term, regular sugar consumption actually changes the gene expression and availability of dopamine receptors in both the midbrain and frontal cortex. Specifically, sugar increases the concentration of a type of excitatory receptor called D1, but decreases another receptor type called D2, which is inhibitory. Regular sugar consumption also inhibits the action of the dopamine transporter, a protein which pumps dopamine out of the synapse and back into the neuron after firing.
In short, this means that repeated access to sugar over time leads to prolonged dopamine signalling, greater excitation of the brain’s reward pathways and a need for even more sugar to activate all of the midbrain dopamine receptors like before. The brain becomes tolerant to sugar – and more is needed to attain the same “sugar high.”
Sugar withdrawal is also real
Although these studies were conducted in rodents, it’s not far-fetched to say that the same primitive processes are occurring in the human brain, too. “The cravings never stopped, [but that was] probably psychological,” Andrew told me. “But it got easier after the first week or so.”In a 2002 study by Carlo Colantuoni and colleagues of Princeton University, rats who had undergone a typical sugar dependence protocol then underwent “sugar withdrawal.” This was facilitated by either food deprivation or treatment with naloxone, a drug used for treating opiate addiction which binds to receptors in the brain’s reward system. Both withdrawal methods led to physical problems, including teeth chattering, paw tremors, and head shaking. Naloxone treatment also appeared to make the rats more anxious, as they spent less time on an elevated apparatus that lacked walls on either side.
Similar withdrawal experiments by others also report behaviour similar to depression in tasks such as the forced swim test. Rats in sugar withdrawal are more likely to show passive behaviours (like floating) than active behaviours (like trying to escape) when placed in water, suggesting feelings of helplessness.
A new study published by Victor Mangabeira and colleagues in this month’s Physiology & Behavior reports that sugar withdrawal is also linked to impulsive behaviour. Initially, rats were trained to receive water by pushing a lever. After training, the animals returned to their home cages and had access to a sugar solution and water, or just water alone. After 30 days, when rats were again given the opportunity to press a lever for water, those who had become dependent on sugar pressed the lever significantly more times than control animals, suggesting impulsive behaviour.
These are extreme experiments, of course. We humans aren’t depriving ourselves of food for 12 hours and then allowing ourselves to binge on soda and doughnuts at the end of the day. But these rodent studies certainly give us insight into the neuro-chemical underpinnings of sugar dependence, withdrawal, and behaviour.
Through decades of diet programmes and best-selling books, we’ve toyed with the notion of “sugar addiction” for a long time. There are accounts of those in “sugar withdrawal” describing food cravings, which can trigger relapse and impulsive eating. There are also countless articles and books about the boundless energy and new-found happiness in those who have sworn off sugar for good. But despite the ubiquity of sugar in our diets, the notion of sugar addiction is still a rather taboo topic.
Are you still motivated to give up sugar? You might wonder how long it will take until you’re free of cravings and side-effects, but there’s no answer – everyone is different and no human studies have been done on this. But after 40 days, it’s clear that Andrew had overcome the worst, likely even reversing some of his altered dopamine signalling. “I remember eating my first sweet and thinking it was too sweet,” he said. “I had to rebuild my tolerance.”
And as regulars of a local bakery in Hershey – I can assure you, readers, that he has done just that.
Jordan Gaines Lewis is a Neuroscience Doctoral Candidate at Penn State College of Medicine
Excerpt from washingtonpost.com
The questions have hung over NASA for years, and emerged again at a Senate committee hearing Tuesday.
Under President George W. Bush, the target was the moon. Under Obama, who said “we’ve been there before,” Mars became the mission.
But now as his term nears its end, there is some increasingly vocal criticism of that decision, saying there isn’t the funding or political will to get to Mars.
Focusing on Mars is a “flawed policy direction,” Scott Pace, the director of the Space Policy Institute at George Washington University testified on Tuesday. The shift in goals “blindsided” the international space community, he said. The moon “is the next logical target for all of our potential international partners.”
Russia has endorsed sending astronauts there, he said. China sent an unmanned rover to the moon, and unveiled designs for a new heavy rocket for deep space exploration. It even has plans to build its own space station. “Growing space powers such as the Republic of Korea and India have their own unmanned lunar ambitions,” Pace said, while adding that the private sector has also made huge advancements.
To regain its prominence in space, the United States should “lead a multinational program to explore the moon," Pace said.
If it doesn’t, he could imagine a “post-American space world, with a full range of manned and unmanned space activities, but without American leadership or even, in many cases, an American presence.”
Testifying before the same committee, Buzz Aldrin, the Apollo 11 pilot who was the second man to walk on the moon, said NASA is right to focus on going beyond the moon. "American leadership is more than simply getting one step ahead of our global competitors," he said. "American leadership is inspiring the world by consistently doing what no other nation is capable of doing."
Aldrin said he's working on a plan to get to Mars, and the next president should press ahead with the mission.
“I believe that early in the next administration, the nation must commit to developing a permanent presence on Mars,” he said.
With much fanfare, NASA has trumpeted its “Journey to Mars” campaign. And it has highlighted the unmanned test flight of the Orion capsule last year as evidence of its progress toward reaching the Red Planet. It is also developing a new heavy rocket, known as the Space Launch System, designed to go to Mars and deep space.
But critics have maintained that without the funding to support such an endeavor, the attempt is a little more than a public relations stunt. And while Sen. Ted Cruz (R-Texas) and other members the committee on Tuesday said they were committed to the new rocket, others have been less supportive.
“We made a wrong decision when we went down this road,” Rep. Dana Rohrabacher (R-Calif.) said at a hearing late last year.
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| These two views of Ceres were acquired by NASA’s Dawn spacecraft on Feb. 12, 2015, from a distance of about 52,000 miles (83,000 kilometers) as the dwarf planet rotated. The images, which were taken about 10 hours apart, have been magnified from their original size. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA |
Excerpt from spaceflightnow.com
Images from NASA’s Dawn spacecraft on approach to the dwarf planet Ceres show a world pockmarked by craters and mysterious bright spots, and scientists are eager for a better look in the weeks ahead.
The latest images were taken Feb. 12 at a distance of 52,000 miles, or 83,000 kilometers, from Ceres. NASA released the fresh views Tuesday.
Every picture taken of Ceres in the coming weeks will show greater detail, as Dawn is set to be captured by the Texas-sized world’s gravity March 6. The dwarf planet will pull Dawn into the first of a series of survey orbits 8,400 miles from Ceres around April 23.
The imagery so far reveals Ceres as a cratered world, and Dawn will make a global map of the dwarf planet during its time in orbit.
But several bright spots have captured the attention of scientists.
“As we slowly approach the stage, our eyes transfixed on Ceres and her planetary dance, we find she has beguiled us but left us none the wiser,” said Chris Russell, principal investigator of the Dawn mission, based at UCLA. “We expected to be surprised; we did not expect to be this puzzled.”
The suspense is compounded by Dawn’s slow rate of approach. The probe’s ion propulsion system is gradually nudging Dawn on a trajectory closer to Ceres, eventually moving the spacecraft close enough to be grasped by the 590-mile diameter dwarf planet’s gravity.
“I want to know what is causing the bright spots,” Russell wrote in an email to Spaceflight Now. “The increased resolution seems to have moved us no closer to answering this mystery. I am frustrated by the suspense. This is the one problem of ion propulsion: We are closing in on Ceres very slowly.”
The latest photos have a resolution have 4.9 miles, or 7.8 kilometers, per pixel, according to a NASA press release.
Dawn’s framing camera will take its next set of images Feb. 20 at a range of about 30,000 miles. After late February, the resolution of Dawn’s imagery will be reduced as the spacecraft passes Ceres and flies in front of it, before being pulled closer in early April for insertion into orbit.
Soon after arriving in April, the spacecraft’s instruments will look for the signature of water vapor plumes shooting into space from the surface of Ceres, which may be blanketed in a crust of ice.
Dawn will orbit closest to Ceres in December at an altitude of 232 miles.
Dawn’s mission planners say the spacecraft could operate around Ceres until late 2016.
Ceres is the second destination for NASA’s Dawn mission, which launched in September 2007 and visited asteroid Vesta in 2011 and 2012.
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| Planck has mapped the delicate polarisation of the CMB across the entire sky |
Excerpt from bbc.com
Scientists working on Europe's Planck satellite say the first stars lit up the Universe later than previously thought.
Earlier observations of this radiation had suggested the first generation of stars were bursting into life by about 420 million years after the Big Bang.
Planck's data indicates this great ignition was well established by some 560 million years after it all began.
"This difference of 140 million years might not seem that significant in the context of the 13.8-billion-year history of the cosmos, but proportionately it's actually a very big change in our understanding of how certain key events progressed at the earliest epochs," said Prof George Efstathiou, one of the leaders of the Planck Science Collaboration.
Subtle signal
The assessment is based on studies of the "afterglow" of the Big Bang, the ancient light called the Cosmic Microwave Background (CMB), which still washes over the Earth today.
Prof George Efstathiou: "We don't need more complicated explanations"
It contains a wealth of information about early conditions in the Universe, and can even be used to work out its age, shape and do an inventory of its contents.
Scientists can also probe it for very subtle "distortions" that tell them about any interactions the CMB has had on its way to us.
Forging elements
One of these would have been imprinted when the infant cosmos underwent a major environmental change known as re-ionisation.
Prof Richard McMahon: "The two sides of the bridge now join"
These hot giants would have burnt brilliant but brief lives, producing the very first heavy elements. But they would also have "fried" the neutral gas around them - ripping electrons off the hydrogen protons.
And it is the passage of the CMB through this maze of electrons and protons that would have resulted in it picking up a subtle polarisation.
Impression: The first stars would have been unwieldy behemoths that burnt brief but brilliant lives The Planck team has now analysed this polarisation in fine detail and determined it to have been generated at 560 million years after the Big Bang.
The American satellite WMAP, which operated in the 2000s, made the previous best estimate for the peak of re-ionisation at 420 million years.
The problem with that number was that it sat at odds with Hubble Space Telescope observations of the early Universe.
Hubble could not find stars and galaxies in sufficient numbers to deliver the scale of environmental change at the time when WMAP suggested it was occurring.
Planck's new timing "effectively solves the conflict," commented Prof Richard McMahon from Cambridge University, UK.
"We had two groups of astronomers who were basically working on different sides of the problem. The Planck people came at it from the Big Bang side, while those of us who work on galaxies came at it from the 'now side'.
"It's like a bridge being built over a river. The two sides do now join where previously we had a gap," he told BBC News.
That gap had prompted scientists to invoke complicated scenarios to initiate re-ionisation, including the possibility that there might have been an even earlier population of giant stars or energetic black holes. Such solutions are no longer needed.
No-one knows the exact timing of the very first individual stars. All Planck does is tell us when large numbers of these stars had gathered into galaxies of sufficient strength to alter the cosmic environment.
By definition, this puts the ignition of the "founding stars" well before 560 million years after the Big Bang. Quite how far back in time, though, is uncertain. Perhaps, it was as early as 200 million years. It will be the job of the next generation of observatories like Hubble's successor, the James Webb Space Telescope, to try to find the answer.
Being built now: The James Webb telescope will conduct a survey of the first galaxies and their stars
- Planck's CMB studies indicate the Big Bang was 13.8bn years ago
- The CMB itself can be thought of as the 'afterglow' of the Big Bang
- It spreads across the cosmos some 380,000 years after the Big Bang
- This is when the conditions cool to make neutral hydrogen atoms
- The period before the first stars is often called the 'Dark Ages'
- When the first stars ignite, they 'fry' the neutral gas around them
- These giants also forge the first heavy elements in big explosions
- 'First Light', or 'Cosmic Renaissance', is a key epoch in history
The new Planck result is contained in a raft of new papers just posted on the Esa website.
These papers accompany the latest data release from the satellite that can now be used by the wider scientific community, not just collaboration members.
Dr Andrew Jaffe: "The simplest models for inflation are ruled out"
It was hoped that Planck might find direct evidence in the CMB's polarisation for inflation - the super-rapid expansion of space thought to have occurred just fractions of a second after the Big Bang. This has not been possible. But all the Planck data - temperature and polarisation information - is consistent with that theory, and the precision measurements mean new, tighter constraints have been put on the likely scale of the inflation signal, which other experiments continue to chase.
What is clear from the Planck investigation is that the simplest models for how the super-rapid expansion might have worked are probably no longer tenable, suggesting some exotic physics will eventually be needed to explain it.
"We're now being pushed into a parameter space we didn't expect to be in," said collaboration scientist Dr Andrew Jaffe from Imperial College, UK. "That's OK. We like interesting physics; that's why we're physicists, so there's no problem with that. It's just we had this naïve expectation that the simplest answer would be right, and sometimes it just isn't."
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| Pictured: An artist's impression of the center of the Henize 2-428 planetary nebula, containing two white dwarf stars. (Photo : ESO/L. CALÇADA) |
Excerpt from natureworldnews.com
Reported in the journal Nature, the European Southern Observatory's (ESO) Very Large Telescope (VLT) in Chile was originally studying how some stars produce strangely shaped, asymmetric nebula. They focused on Henize 2-428 and found something they did not expect - not just one star, but two.
"Further observations made with telescopes in the Canary Islands allowed us to determine the orbit of the two stars and deduce both the masses of the two stars and their separation. This was when the biggest surprise was revealed," co-author Romano Corradi, a researcher at the Instituto de Astrofísica de Canarias, said in a press release.
The next shocker was that the two stars were white dwarfs - tiny, extremely dense stars with a total mass about 1.8 times that of the Sun. The fact that there are two stars supports the theory that double central stars may explain the odd shapes of some of these nebulae.
They've also found that the stars orbit every 4 hours and due to the emission of gravitational waves, they are slowly spiraling into one another. Within the next 700 million years, these stars will merge and under the stress of their combined mass, explode in a giant supernova.
"Until now, the formation of supernovae Type Ia by the merging of two white dwarfs was purely theoretical," said co-author David Jones, an ESO Fellow at the time the data were obtained. "The pair of stars in Henize 2-428 is the real thing!"
"It's an extremely enigmatic system," added lead researcher Santander-García. "It will have important repercussions for the study of supernovae Type Ia, which are widely used to measure astronomical distances and were key to the discovery that the expansion of the Universe is accelerating due to dark energy."
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