Tag: methods (page 2 of 5)

Warp in spacetime lets astronomers watch the same star explode four times

March 8, 2015 / / 0 Comments



Excerpt from csmonitor.com

Thanks to a phenomenon known as gravitational lensing, the Hubble Space Telescope has captured four images of the same supernova explosion.

For the first time, a cosmic magnifying glass has allowed scientists to see the same star explosion four times, possibly offering a revealing glimpse into these explosive stellar deaths and the nature of the accelerating universe.

Astronomers using the Hubble Space Telescope have captured four images of a supernova explosion in deep space thanks to a galaxy located between Earth and the massive star explosion. You can see how Hubble saw the supernova in this NASA video. The galaxy cluster warped the fabric of space and time around it — like a bowling ball placed on a bed sheet — allowing scientists to see the supernova in four images.

"It was predicted 50 years ago that a supernova could be gravitationally lensed like this, but it's taken a long time for someone to find an example," lead study author Patrick Kelly, an astronomer at the University of California, Berkeley told Space.com. "It's fun to have been able to find the first one." 

The supernova, which was discovered on Nov. 11, 2014, is located about 9.3 billion light-years away from Earth, near the edge of the observable universe. The researchers have named the distant supernova SN Refsdal in honor of the late Norwegian astrophysicist Sjur Refsdal, a pioneer of gravitational lensing studies. Due to gravitational lensing, "the supernova appears 20 times brighter than its normal brightness," study co-author Jens Hjorth, head of the Dark Cosmology Centre at the Niels Bohr Institute at the University of Copenhagen, said in a statement.
The lensing galaxy, which is about 5 billion light-years from Earth, is part of a large cluster of galaxies known MACS J1149.6+2223. In 2009, astronomers discovered that this cluster was the source of the largest known image of a spiral galaxy ever seen through a gravitational lens.

The four images of the supernova each appeared separately over the course of a few weeks. This is because light can take various paths around and through a gravitational lens, arriving at Earth at different times.

Using gravity as a lens

Gravity is created when matter warps the fabric of reality. The greater the mass of an object, the more space-time curves around that object and the stronger its gravitational pull, the discovery enshrined in Einstein's theory of general relativity, which celebrates its centennial this year.

As a result, gravity can also bend light like a lens, meaning objects see n behind powerful gravitational fields, such as those of massive galaxies, are magnified. Gravitational lensing was first discovered in 1979, and today gravitational lenses can help astronomers see features otherwise too distant and faint to detect with even the largest telescopes.

"These gravitational lenses are like a natural magnifying glass. It's like having a much bigger telescope," Kelly said in a statement. "We can get magnifications of up to 100 times by looking through these galaxy clusters."

When light is far from a gravitationally lensing mass, or if the gravitationally lensing mass is not especially large, only "weak lensing" occurs, barely distorting the light. However, when the light comes from almost exactly behind the gravitationally lensing mass, "strong lensing" can happen. 

When a strongly lensed object occupies a large patch of space — for instance, if it's a galaxy — it can get smeared into an "Einstein ring" surrounding a gravitationally lensing mass. However, strong lensing of small, pointlike items — for instance, super-bright objects known as quasars — often produces multiple images surrounding the gravitationally lensing mass, resulting in a so-called "Einstein cross."

The observations of SN Refsdal mark the first time astronomers on Earth have witnessed strong lensing of a  supernova, with four images of an exploding star arrayed as an Einstein cross.

An expanding universe

These new findings could help scientists measure the accelerating rate at which the universe is expanding, researchers say.

A computer model of the lensing cluster suggests the scientists missed chances to see the lensed supernova 50 and 10 years ago. However, the model also suggests more images of the explosion will repeat again within the next 10 years.

The timing of when all these images of the supernova arrive depends on the gravitational pull of the matter generating the gravitational lens. So, by measuring those times, the researchers hope to map how visible normal matter and invisible dark matter is distributed in the lensing galaxy.

Dark matter is currently one of the greatest mysteries in science, a poorly understood substance thought to make up five-sixths of all matter in the universe. A better understanding of how dark matter is behaving in this gravitationally lensing cluster might help shed light on the material's nature, Kelly said.

Analyzing when the images arrive could also help scientists pinpoint the rate at which the universe is expanding. Although there are already several ways to measure the cosmic expansion rate, "there has been a lot of heated debate between different methods, so it'd be interesting to see how this new technique might affect the area," Kelly said. "It's always nice to have completely independent measurements of the same quantity."

The scientists detailed their findings in the March 6 issue of the journal Science.

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What happens to your body when you give up sugar?

March 4, 2015 / / 0 Comments





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

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What It’s Like to Be at the 24th International UFO Congress

February 26, 2015 / / 0 Comments







Excerpt from nbcnews.com
By Katie Linendoll
FOUNTAIN HILLS, Ariz. — If words like UFO, extraterrestrial, crops circles and abductee have ever piqued your paranormal interest, do yourself a favor and head to the International UFO Congress. 

The annual conference—which holds the Guinness record for being the largest convention dedicated to unidentified flying objects—takes place in the picturesque desert town of Fountain Hills, and this year it ran from Feb. 18 to 22. It's worth noting that Arizona is known as a hotbed of activity when it comes to sightings. Thousands flock to the annual event, which is produced by Open Minds, a paranormal research organization. 

Each attendee has his or her own reason for being there. My goal was to find out if modern science and technology have changed the game when it comes to UFO sightings and evidence gathering. 

"A lot of people think, go to a UFO convention, it's going to be tinfoil hats, but that's not what this is. We have NASA astrobiologists speak, scientists, high-ranking military officials, the works. I mean, there's a lot of really credible people covering this subject," said UFO Congress co-organizer and paranormal journalist Maureen Elsberry.

Air Force UFO documents now available online

When attending a UFO conference, the best approach is to come in with an open mind, ask lots of questions and talk with people about why they are there. Everyone has a story, from the speakers to the attendees, and even the vendors (some of whom double as ufologists). 

The highlight of this year's conference was undeniably the speaker series, and it was standing room only to see one man, Bob Lazar. Lazar first spoke out in 1989, claiming that he'd worked as a government scientist at a secret mountainside facility south of Area 51's main site, where he saw remarkably advanced UFO technology. Critics have sought to discredit Lazar, questioning his employment record and educational credentials. 

During the conference, George Knapp, an investigative TV reporter in Las Vegas who broke the Lazar story in '89, led an onstage question-and-answer session with Lazar, who discussed the work he did at a place called S4. Lazar spoke in detail about the alien UFO hangars and UFO propulsion systems he was allegedly asked to reverse engineer, and even loosely sketched them out for the audience. 

"All the science fiction had become reality," said Lazar, who was noticeably uncomfortable and clearly surprised by the fact that, decades later, he remains such a draw. 

You never know whom you'll bump into at the Congress. In the vendor hall, I met sculptor Alan Groves, who traveled all the way from Australia to peddle his "true to scale" Zetan alien figurines. I wondered if his side gig was lucrative, only to realize he was selling the figures like hotcakes. Then we talked about his day job, and he told me he's worked on special and creature effects for films such as "Star Wars," "Alien," "Labyrinth" and "Jurassic Park." 

Many of the attendees told me that hard evidence is a requirement for ufologists and paranormal field experts. Derrel Sims, also known as Alien Hunter, told me he spent two years in the CIA, and also has served as a police officer and licensed private investigator. 

He said his first alien encounter happened at age 4, and others in his family have also seen aliens. In 38-plus years of alien research, Sims has learned this: "If you look, the evidence is there." To date, he said, more than 4,000 pieces of that evidence exist. 

Sims is adamant about only working with evidence-based methods, using DNA tests and collecting samples as well as relying on ultraviolet, infrared and x-ray tools in his research. He said that, in 1992, he discovered aliens leave their own kind of fluorescent fingerprint, and he continues to test for these clues. He added that if you have had an alien encounter, it's important to react quickly to gather evidence: "fluorescence" stays on the skin for only 24 hours. He said that other marks aliens leave include "scoop" marks, which are an identifying thread some abductees have in common. 

Another commonality he's discovered is heritage. He said that, in his research, he has found 45 percent of all abductions happen to Native Americans, Irish and Celtic people, and he said that women also have a higher chance of being abducted. 

When it comes to filming hard-to-explain phenomena, Patty Greer, who makes documentaries about crop circles, said that quadcopters — a.k.a. drones — have added production value to her films. Lynne Kitei, who covered a mass UFO sighting in her book and in the documentary The Phoenix Lights, said that even low-tech tools, like the 35mm film she used, are still a reliable way to gather proof of inexplicable flying craft, especially because they offer something an iPhone doesn't: negatives.

White House responds to UFO request

Night vision also offers added opportunities for UFO researchers, according to Ben Hansen, who was the host and lead investigator of SyFy channel's "Fact or Faked: Paranormal Files." He's now the owner of Night Vision Ops, an online store that sells night-vision technology. Hansen said that the consumer accessibility of new military-grade technologies in thermal and light amplification scopes are upping the game for the everyday UFO enthusiast. 

To close out an intense few days on site at the Congress, Hansen's team invited me to a night watch near Arizona's Superstition Mountains. It was fascinating to see the latest optics add incredible clarity to the night sky, amplifying available light up to 50,000 times beyond what the unaided eye can see. Using the right technology, we were also able to see that a certain flying object, which made everyone nearby jump, wasn't a UFO after all. It was a bat. 

I was surrounded by some serious tech all weekend, and it was eye-opening to see the ways that UFO hunters are gathering scientific evidence to learn more about the paranormal world. But I have to say, the gadget that was the most useful to me at the conference was my iPhone, which I used to download a free nightlight app for kids. For the few hours I managed to sleep, it was with the soothing illumination provided by "Kiwi the Green Koala." In short, I was officially freaked out.

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Google’s AI Program Is Better At Video Games Than You

February 26, 2015 / / 0 Comments





pcmag.com

IBM's Watson supercomputer may be saving lives and educating children, but Google's new AI program can master video games without human guidance.

The artificial intelligence system from London-based DeepMind, which Google acquired last year for a reported $400 million, represents a major step toward a future of smart machines.

Computers running the deep Q-network (DQN) algorithm were exposed to 49 retro games on the Atari 2600 and told to play them, without any direction from researchers. Using the same network architecture and tuning parameters, the machines were given only raw screen pixels, available actions, and game score as input.

For each level passed or high score earned, the computer was automatically rewarded with a digital treat.

"Strikingly, DQN was able to work straight 'out of the box' across all these games," DeepMind's Dharshan Kumaran and Demis Hassabis wrote in a blog post. The executives cited classic titles like Breakout, River Raid, Boxing, and Enduro.

The AI crushed even the most expert humans at 29 games, sometimes composing what the creators called "surprisingly far-sighted strategies" that allowed maximum scoring possibilities. It also outperformed previous machine-learning methods in 43 of 49 instances.

VIEW ALL PHOTOS IN GALLERY
Google DeepMind's findings were presented in a paper published in this week's Nature journal, which describes the key DQN features that allow it to learn.

"This work offers the first demonstration of a general purpose learning agent that can be trained end-to-end to handle a wide variety of challenging tasks," the researchers said. "This kind of technology should help us build more useful products."

Imagine asking the Google app to complete a complex task—like plan a backpacking trip through Europe, for example.

Google's DeepMind also hopes its technology will give researchers new ways to make sense of large-scale data, opening the door to discoveries in fields like climate science, physics, medicine, and genomics.

"And it may even help scientists better understand the process by which humans learn," Kumaran and Hassabis said, citing physicist Richard Feynman, who famously said, "What I cannot create, I do not understand."

For more, see How DeepMind Can Bring Google Artificial Intelligence to Life in the slideshow above.

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Stephen Hawking warns that attempting to contact aliens could invite disaster

February 13, 2015 / / 0 Comments

Excerpt from cambridge-news.co.ukWhat is known as Active Seti will be under serious discussion this week at the annual meeting of the American Association for the Advancement of Science (AAAS) in San Jose, California. Seti spokesman Dr Seth...

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Yes, that 3D-printed mansion is safe to live in

February 13, 2015 / / 0 Comments


WinSun claims that their new 3D printed five-story building is the tallest of its kind in the world. Credit: 3ders.org
WinSun claims that their new 3D printed five-story building is the tallest of its kind in the world. 


Excerpt from

Back in April, a team of Chinese construction workers used a 3D printer to construct houses. By day’s end, there were 10 standing. They were compact and fairly bare bones — nothing much to look at besides the “wow!” factor of there being as many as — count them — 10. But this time around, those same builders have taken the wraps off an achievement that’s roundly more impressive.
In Suzhou Industrial Park, adjacent to Shanghai, stands a five-story structure that the WinSun Decoration Design Engineering firm claims is “the world’s tallest 3D-printed building.” Next to it is the equally massive 3D-printed mansion, which measures 11,840 square feet. Like the previous buildings, the walls are comprised of a mix of concrete and recycled waste materials, such as glass and steel, and formed layer by printed layer. The company stated that the total cost for the mansion was roughly $161,000. 
In a broader sense, this latest feat is yet another indication of how rapidly additive manufacturing techniques are advancing. Once used primarily as a means to quickly render miniature model versions of products, the technology has reached a point where large-scale printers are now capable of making life-sized working creations, such as automobiles, in mere days. For instance, it took less than 48 hours for start-up Local Motors to print a two-seater called the Strati into existence and drive it off the showroom.
Many of these designs, however, typically don’t amount to much beyond being passion projects meant to push 3D printing into new frontiers and drum up some publicity along the way. One example of this is the massive 3D Print Canal House that’s being constructed entirely on-site along a canal in Amsterdam, a process that’s slated to take longer and is less feasible than standard construction, Phil Reeves of UK-based 3D printing research firm Econolyst recently told CNN.
More promising, though, is a system developed by Behrokh Khoshnevis, a University of Southern California engineering professor. His concept machine, called Contour Crafting, involves a clever combination of mechanical cranes and 3D layering to print and assemble entire homes simultaneously — complete with insulation and indoor plumbing — in less than a day. 

Assembling 3D printed buildings is quite similar to erecting prefab homes. Credit: 3ders.org
Assembling 3D printed buildings is quite similar to erecting prefab homes. 


The approach employed by WinSun isn’t anywhere near that level of sophistication, but it may well prove to be the most practical – at least thus far. There is some labor and equipment costs that comes from trucking in and piecing together the various sections on-site, though the manner in which it all comes together is comparable to the ease of prefab assembly. It’s also reportedly greener thanks to the addition of recycled materials. 
To pitch the advantages of their technology, the company held a news conference to announce that they had taken on orders for 20,000 smaller units as well as highlight some significant cost-cutting figures. According toindustry news site 3Der:
The sheer size of the printer allows for a 10x increase in production efficiency. WinSun estimates that 3D printing technology can save between 30 and 60 percent of building materials and shortens production times by 50 to even 70 percent, while decreasing labor costs by 50 up to even 80 percent. Future applications include 3D printed bridges or tall office buildings that can be built right on site.
WinSun did not respond to a request to disclose how they arrived at those numbers, but Enrico Dini, an Italian civil engineer and chairman of competing start-up Monolite, says that he suspects the calculations may be a tad bit inflated. Still, he emphasized that his own data does back up the claim that, compared to conventional methods, layering may boost overall efficiency. 
“It would be very difficult to fabricate such large sections with traditional concrete casting,” he says. “With 3D printing, you have a lot less waste because you’re only printing out as much material as you need and you can custom shape whole sections on the spot, which can be a big challenge.”

WinSuns 3D printed villa has several rooms and has been deemed to be up to Chinas national safety standards. Credit: 3ders.org
WinSun’s 3D-printed villa has several rooms and has been deemed to be up to China’s national safety standards.

One major concern is whether these large-scale dwellings can hold up over time against the elements. According to 3Der, Ma Rongquan, chief engineer of China Construction Bureau, inspected the building’s structural integrity and found them to be up to code, but was careful to note that state officials have yet to establish specific criteria for assessing the long-term safety of 3D printed architecture.   
And as Dini, who supports the technology, points out, there is the possibility that the use of additive manufacturing may pose some degree of risk. “The only issue is that as the layers of concrete are bonded together, they’re drying at slightly different rates and that’s not very ideal,” he explains. “So there’s maybe a higher chance of it fracturing at the contact point if there’s a strong enough force at play.” 
Regardless, Dini says he’d feel completely safe going inside any floor of either building since construction materials used today are likely to contain special additives to enhance strength and resistance. One such formulation, fiber-reinforced Ductal, has been shown in some tests to be 10 times stronger and last twice as long as regular concrete. He stressed that walls should also be tested to ensure that other properties, such as acoustics, ventilation and thermal insulations are on par with existing buildings.
“In Italy, building standards are extremely strict,” he noted. “But I can’t say I can say the same about China.”

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Hubble Juiced! ~ CU-Boulder to Design Space Telescope 1000 Times Sharper than Hubble

January 31, 2015 / / 0 Comments



CU-Boulder to Design Space Telescope 1000 Times Sharper than Hubble
The Hubble Space Telescope


Excerpt from utahpeoplespost.com


Researchers from the Department of Astrophysical and Planetary Sciences at the University of Colorado Boulder are currently working on an improved version of space telescope that could provide space images nearly 1,000 times sharper than those provided by long-running Hubble.

The new space telescope, dubbed the Aragoscope, is named after a French astronomer called Francois Arago. The new telescope is exclusively designed by the CU- Boulder scientists and involves a brand new technology developed by the university. According to its designers, the space optical instrument would be lighter, slimmer, and sharper than Hubble.

Additionally, the Aragoscope will involve several independent pieces that can be later assembled in space. So, the launching costs of these smaller building blocks will be significantly reduced.
Traditionally, space telescopes have essentially been monolithic pieces of glass like the Hubble Space Telescope. But the heavier the space telescope, the more expensive the cost of the launch,”
said Anthony Harness, one of the researchers involved in the project and doctoral student at the CU-Boulder.

However, the new instrument will not replace Hubble, which is scheduled to be shut down in 5 years time. Last year, Hubble had its fifth and final maintenance service, and it was still in a pretty good shape although one of its six gyroscopes couldn’t be stabilized. Despite Hubble has been operating since 1990, NASA engineers hope that it will make it to its 30th anniversary.

If Hubble remains operational, NASA plans to use it along with its successor, the James Webb Space Telescope, which is scheduled to be launched in October 2018. Astronomers hope that the two space telescopes, which use two different imaging methods, would help them better understand the origins and early evolution of the universe.

But the UC-Boulder team claim that their new space telescope would surpass Hubble with its enhanced capacity of spotting distant Earth-like planets in the depths of a remote universe...

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The Best Star Gazing Binoculars for 2015

January 24, 2015 / / 0 Comments




Excerpt from space.com

Most people have two eyes. Humans evolved to use them together (not all animals do). People form a continuous, stereoscopic panorama movie of the world within in their minds. With your two eyes tilted upward on a clear night, there's nothing standing between you and the universe. The easiest way to enhance your enjoyment of the night sky is to paint your brain with two channels of stronger starlight with a pair of binoculars. Even if you live in — or near — a large, light-polluted city, you may be surprised at how much astronomical detail you'll see through the right binoculars!
Our editors have looked at the spectrum of current binocular offerings. Thanks to computer-aided design and manufacturing, there have never been more high-quality choices at reasonable prices. Sadly, there's also a bunch of junk out there masquerading as fine stargazing instrumentation. We've selected a few that we think will work for most skywatchers.
There was a lot to consider: magnification versus mass, field of view, prism type, optical quality ("sharpness"), light transmission, age of the user (to match "exit pupil" size, which changes as we grow older), shock resistance, waterproofing and more. 

The best binoculars for you

"Small" astronomy binoculars would probably be considered "medium" for bird watching, sports observation and other terrestrial purposes. This comes about as a consequence of optics (prism type and objective size, mostly). "Large" binoculars are difficult to use for terrestrial applications and have a narrow field of view. They begin to approach telescope quality in magnification, resolution and optical characteristics.

Most of our Editors' Choicesfor stargazing binoculars here are under $300. You can pay more than 10 times that for enormous binocular telescopes used by elite enthusiasts on special mounts! You'll also pay more for ruggedized ("mil spec," or military standard) binoculars, many of which suspend their prisms on shock mounts to keep the optics in precise alignment.

Also, our Editors' Choices use Porro prism optics. Compact binoculars usually employ "roof" prisms, which can be cast more cheaply, but whose quality can vary widely. [There's much more about Porro prisms in our Buyer's Guide.]
We think your needs are best served by reviewing in three categories.
  • Small, highly portable binoculars can be hand-held for viewing ease.
  • Medium binoculars offer higher powers of magnification, but still can be hand-held, if firmly braced.
  • Large binoculars have bigger "objective" lenses but must be mounted on a tripod or counterweighted arm for stability.
Here's a detailed look at our Editor's Choice selections for stargazing binoculars:

Best Small Binoculars 

Editor's Choice: Oberwerk Mariner 8x40 (Cost: $150)

Oberwerk in German means "above work." The brand does indeed perform high-level optical work, perfect for looking at objects above, as well as on the ground or water. Founder Kevin Busarow's Mariner series is not his top of the line, but it benefits greatly from engineering developed for his pricier models. The Oberwerk 8x40’s treat your eyes to an extremely wide field, at very high contrast, with razor-sharp focus; they are superb for observing the broad starscapes of the Milky Way. Just 5.5 inches (14 cm) from front to back and 6.5 inches wide (16.5 cm), the Mariners are compact and rugged enough to be your favorite "grab and go binoculars." But at 37 ounces, they may be more than a small person wants to carry for a long time.


Runner-Up: Celestron Cometron 7x50 (Cost: $30)

Yes, you read that price correctly! These Celestron lightweight, wide-field binoculars bring honest quality at a remarkably low price point. The compromise comes in the optics, particularly the prism's glass type (you might see a little more chromatic aberration around the edges of the moon, and the exit pupil isn't a nice, round circle). Optimized for "almost infinitely distant" celestial objects, these Cometrons won't focus closer than about 30 feet (9.1 meters).  But that's fine for most sports and other outdoor use. If you're gift-buying for multiple young astronomers – or you want an inexpensive second set for yourself – these binoculars could be your answer. Just maybe remind those young folks to be a little careful around water; Celestron claims only that the Cometrons are "water resistant," not waterproof. 


Honorable Mention: Swarovski Habicht 8x30 (Cost: $1,050)

From the legendary Austrian firm of Swarovski Optik, these "bins" are perfect. Really. Very sharp. Very lightweight. Very wide field. Very versatile. And very expensive! Our editors would have picked them if we could have afforded them. 

Honorable Mention: Nikon Aculon 7x50 (Cost: $110) 

Nikon's legendary optical quality and the large, 7mm exit pupil diameter make these appropriate as a gift for younger skywatchers. 

Best Medium Binoculars

Editor's Choice: Celestron SkyMaster 8x56 (Cost: $210)

A solid, chunky-feeling set of quality prisms and lenses makes these binoculars a pleasant, 38oz. handful. A medium wide 5.8 degrees filed of view and large 7mm exit pupil brings you gently into a sweet sky of bright, though perhaps not totally brilliant, stars. Fully dressed in a rubber wetsuit, these SkyMasters are waterproof. Feel free to take them boating or birding on a moist morning. Their optical tubes were blown out with dry nitrogen at the factory, then sealed. So you can expect them not to fog up, at least not from the inside. Celestron's strap-mounting points on the Skymaster 8x56 are recessed, so they don't bother your thumbs, but that location makes them hard to fasten. 


Runner-Up: Oberwerk Ultra 15x70 (Cost: $380)

The most rugged pair we evaluated, these 15x70s are optically outstanding. Seen through the Ultra's exquisitely multi-coated glass, you may find yourself falling in love with the sky all over again. Oberwerk's method of suspending their BAK4 glass Porro prisms offers greater shock-resistance than most competitors’ designs. While more costly than some comparable binoculars, they deliver superior value. Our only complaint is with their mass: At 5.5 lbs., these guys are heavy!  You can hand-hold them for a short while, if you’re lying down. But they are best placed on a tripod, or on a counterweighted arm, unless you like shaky squiggles where your point-source stars are supposed to be. Like most truly big binoculars, the eyepieces focus independently; there’s no center focus wheel. These "binos" are for true astronomers. 


Honorable Mention: Vixen Ascot 10x50 (Cost:$165)

These quirky binoculars present you with an extremely wide field. But they are not crash-worthy – don't drop them in the dark – nor are they waterproof, and the focus knob is not conveniently located. So care is needed if you opt for these Vixen optics. 

Best Large Binoculars

Don't even think about hand-holding this 156-ounce beast! The SkyMaster 25x100 is really a pair of side-by-side 100mm short-tube refractor telescopes. Factor the cost of a sturdy tripod into your purchase decision, if you want to go this big.  The monster Celestron comes with a sturdy support spar for mounting. Its properly multi-coated optics will haul in surprising detail from the sky.  Just make sure your skies are dark; with this much magnification, light pollution can render your images dingy. As with many in the giant and super-giant class of binoculars, the oculars (non-removable eyepieces) focus separately, each rotating through an unusually long 450 degrees.  Getting to critical focus can be challenging, but the view is worth it. You can resolve a bit of detail on face of the new moon (lit by "Earthshine") and pick out cloud bands on Jupiter; tha's pretty astonishing for binoculars. 


Runner-Up: Orion Astronomy 20x80 (Cost: $150)

These big Orions distinguish themselves by price point; they're an excellent value. You could pay 10 times more for the comparably sized Steiners Military Observer 20x80 binoculars! Yes, the Orions are more delicate, a bit less bright and not quite as sharp. But they do offer amazingly high contrast; you'll catch significant detail in galaxies, comets and other "fuzzies." Unusually among such big rigs, the Astronomy 20x80 uses a center focus ring and one "diopter" (rather than independently focusing oculars); if you’re graduating from smaller binoculars, which commonly use that approach, this may be a comfort. These binoculars are almost lightweight enough to hold them by hand. But don't do that, at least not for long periods. And don't drop them. They will go out of alignment if handled roughly. 


Honorable Mention: Barska Cosmos 25x100 (Cost: $230)

They are not pretty, but you're in the dark, right? Built around a tripod-mountable truss tube, these Barskas equilibrate to temperature quickly and give you decent viewing at rational cost. They make for a cheaper version of our Editors' Choice Celestron SkyMasters. 

Honorable Mention: Steiner Observer 20x80 (Cost: $1,500)

Not at all a practical cost choice for a beginning stargazer, but you can dream, can't you? These Steiner binoculars are essentially military optics "plowshared" for peaceful celestial observing. 

Why we chose NOT to review certain types

Image stabilized?

Binoculars with active internal image stabilization are a growing breed. Most use battery-powered gyroscope/accelerometer-driven dynamic optical elements. We have left this type out of our evaluation because they are highly specialized and pricey ($1,250 and up). But if you are considering active stabilization, you can apply the same judgment methods detailed in our Buyer's Guide.

Comes with a camera?

A few binoculars are sold with built-in cameras. That seems like a good idea. But it isn't, at least not for skywatching. Other than Earth's moon, objects in the night sky are stingy with their photons. It takes a lengthy, rock-steady time exposure to collect enough light for a respectable image. By all means, consider these binocular-camera combos for snapping Facebook shots of little Jenny on the soccer field. But stay away from them for astronomy.

Mega monster-sized?

Take your new binoculars out under the night sky on clear nights, and you will fall in love with the universe. You will crave more ancient light from those distant suns. That may translate into a strong desire for bigger stereo-light buckets.

Caution: The next level up is a quantum jump of at least one financial order of magnitude. But if you have the disposable income and frequent access to dark skies, you may want to go REALLY big. Binocular telescopes in this class can feature interchangeable matching eyepieces, individually focusing oculars, more than 30x magnification and sturdy special-purpose tripods. Amateurs using these elite-level stereoscopes have discovered several prominent comets.

Enjoy your universe

If you are new to lens-assisted stargazing, you'll find excellent enhanced views among the binocular choices above. To get in deeper and to understand how we picked the ones we did, jump to our Buyer's Guide: How to Choose Binoculars for Sky Watching.

You have just taken the first step to lighting up your brain with star fire. May the photons be with you. Always. 

Skywatching Events 2015

Once you have your new binoculars, it's time to take them for a spin. This year intrepid stargazers will have plenty of good opportunities to use new gear.

On March 20, for example, the sun will go through a total solar eclipse. You can check out the celestial sight using the right sun-blocking filters for binoculars, but NEVER look at the sun directly, even during a solar eclipse. It's important to find the proper filters in order to observe the rare cosmic show. 

Observers can also take a look at the craggy face of the moon during a lunar eclipse on April 4. Stargazers using binoculars should be able to pick out some details not usually seen by the naked eye when looking at Earth's natural satellite.

Skywatchers should also peek out from behind the binoculars for a chance to see a series of annual meteor showers throughout the year.

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Google Chairman Eric Schmidt: "The Internet Will Disappear"

January 23, 2015 / / 0 Comments


 


Excerpt from hollywoodreporter.com

Google executive chairman Eric Schmidt on Thursday predicted the end of the Internet as we know it.

At the end of a panel at the World Economic Forum in Davos, Switzerland, where his comments were webcast, he was asked for his prediction on the future of the web. “I will answer very simply that the Internet will disappear,” Schmidt said.

“There will be so many IP addresses…so many devices, sensors, things that you are wearing, things that you are interacting with that you won’t even sense it,” he explained. “It will be part of your presence all the time. Imagine you walk into a room, and the room is dynamic. And with your permission and all of that, you are interacting with the things going on in the room.”

Concluded Schmidt: “A highly personalized, highly interactive and very, very interesting world emerges.”

The panel, entitled The Future of the Digital Economy, also featured Facebook COO Sheryl Sandberg and others.
Earlier in the debate, Schmidt discussed the issue of market dominance. The European Union has been looking at Google’s search market dominance in a long-running antitrust case, and the European parliament late last year even called for a breakup.
“You now see so many strong tech platforms coming, and you are seeing a reordering and a future reordering of dominance or leaders or whatever term you want to use because of the rise of the apps on the smartphone,” Schmidt said Thursday. “All bets are off at this point as to what the smartphone app infrastructure is going to look like” as a “whole new set” of players emerges to power smartphones, which are nothing but super-computers, the Google chairman argued. “I view that as a completely open market at this point.”

Asked about his recent trip to North Korea, Schmidt said the country has many Internet connections through data phones, but there is no roaming and web usage is “heavily supervised.” Schmidt said “it’s very much surveillance of use,” which he said was not good for the country and others.

Sandberg and Schmidt lauded the Internet as an important way to give more people in the world a voice. Currently, only 40 percent of people have Internet access, the Facebook COO said, adding that any growth in reach helps extend people’s voice and increase economic opportunity. “I’m a huge optimist,” she said about her outlook for the industry. “Imagine what we can do” once the world gets to 50 percent, 60 percent and more in terms of Internet penetration.
She cited women as being among the beneficiaries, saying the Internet narrows divides.

Schmidt similarly said that broadband can address governance issues, information needs, personal issues, women empowerment needs and education issues. “The Internet is the greatest empowerment of citizens … in many years,” he said. “Suddenly citizens have a voice, they can be heard.”
During another technology panel at the World Economic Forum on Thursday, Yahoo CEO Marissa Mayer, Liberty Global CEO Mike Fries and others answered questions on the need to regulate privacy standards on the Internet and for tech companies following the Snowden case, the Sony hack and the like.

Mayer said that the personalized Internet “is a better Internet,” emphasizing: “We don’t sell your personal data … We don’t transfer your personal data to third parties.” She said users own their data and need to have control, adding that people give up data to the government for tax assessment, social services and other purposes.
Fries said Liberty Global subscribers view billions of hours of content and generate billions of clicks, but added that “today we do nothing.” He explained: “We generate zero revenue from all of that information.” But he acknowledged that big data was big business for a lot of people.

Both executives said transparency was important to make sure users know privacy standards and the like.

Gunther Oettinger, a conservative German politician serving as the European Union’s commissioner for digital economy and society, said on the panel that “we need a convincing global understanding, we need a UN agency for data protection and security.” Asked what form that “understanding” should have, he said he was looking for “clear, pragmatic, market-based regulation.” Explained Oettinger: “It’s a public-private partnership.”

Fries said such a solution was likely not to happen in the near term, given the size of the EU. “I think it is going to take several years,” he said, adding that some countries’ parliaments would likely take a stab at it.

But he warned that a joint solution would make more sense. “We don’t want Germany to have its own Internet,” Fries said. “Some countries may build their own Internets” and “balkanize” the web, he warned.

Mayer said on the issue of regulation: “I like Tim’s idea better of the beneficent marketplace.” She spoke of fellow panelist and computer specialist Tim Berners-Lee, known as the inventor of the World Wide Web.

Asked how Yahoo stores and handles client records, she said the online giant “changed the way we store and communicate data” after Snowden and also changed encryptions between data centers. And the company protects users through encryption methods, she added. Mayer said that trust and confidence of Yahoo users has rebounded since.

Mayer was also asked what happens if a government asks for a user’s data, a question that has new significance after the recent terrorist attacks in Paris, which have led some to call for increased surveillance powers of the Internet for governments. Mayer said Yahoo always assesses if such a request is reasonable. “We have a very good track record for standing up to what’s not reasonable,” she said.

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

January 20, 2015 / / 0 Comments


Mount Vesuvius today



By Amina Khan 
Excerpt from latimes.com

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

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

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

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

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

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

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


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

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The Best Bet for Alien Life May Be in Planetary Systems Very Different From Ours

January 16, 2015 / / 0 Comments




Excerpt from wired.com


In the hunt for extraterrestrial life, scientists started by searching for a world orbiting a star just like the sun. After all, the steady warmth of that glowing yellow ball in the sky makes life on Earth possible.

But as astronomers continue to discover thousands of planets, they’re realizing that if (or when) we find signs of extraterrestrial life, chances are good that those aliens will orbit a star quite different from the sun—one that’s redder, cooler, and at a fraction of the sun’s size and mass. So in the quest for otherworldly life, many astronomers have set their sights on these small stars, known as red dwarfs or M dwarfs.

At first, planet-hunting astronomers didn’t care so much about M dwarfs. After the first planet outside the solar system was discovered in 1995, scientists began hunting for a true Earth twin: a rocky planet like Earth with an orbit like ours around a sun-like star. Indeed, the search for that kind of system drove astronomers through most of the 2000s, says astronomer Phil Muirhead of Boston University.

But then astronomers realized that it might be technically easier to find planets around M dwarfs. Detecting another planet is really hard, and scientists rely on two main methods. In the first, they look for a drop in a star’s brightness when a planet passes in front of it. In the second, astronomers measure the slight wobble of a star, caused by the gentle gravitational tug of an orbiting planet. With both of these techniques, the signal is stronger and easier to detect for a planet orbiting an M dwarf. A planet around an M dwarf also orbits more frequently, increasing the chances that astronomers will spot it.

M dwarfs got a big boost from the Kepler space telescope, which launched in 2008. By staring at small patch of the sky, the telescope searches for suddenly dimming stars when a planet passes in front of them. In doing so, the spacecraft discovered a glut of planets—more than 1,000 at the latest count—it found a lot of planets around M dwarfs. “Kepler changed everything,” Muirhead said. Because M-dwarf systems are easier to find, the bounty of such planets is at least partly due to a selection effect. But, as Muirhead points out, Kepler is also designed to find Earth-sized planets around sun-like stars, and the numbers so far suggest that M-dwarfs may offer the best odds for finding life.

“By sheer luck you would be more likely to find a potentially habitable planet around an M dwarf than a star like the sun,” said astronomer Courtney Dressing of Harvard. She led an analysis to estimate how many Earth-sized planets—which she defined as those with radii ranging from one to one-and-a-half times Earth’s radius—orbit M dwarfs in the habitable zone, the region around the star where liquid water can exist on the planet’s surface. According to her latest calculations, one in four M dwarfs hosts such a planet.

That’s higher than the estimated number of Earth-sized planets around a sun-like star, she says. For example, an analysis by astronomer Erik Petigura of UC Berkeley suggests that fewer than 10 percent of sun-like stars have a planet with a radius between one and two times that of Earth’s.

This illustration shows Kepler-186f, the first rocky planet found in a star's habitable zone. Its star is an M dwarf.
This illustration shows Kepler-186f, the first rocky planet found in a star’s habitable zone. Its star is an M dwarf. NASA Ames/SETI Institute/JPL-Caltech


M dwarfs have another thing going for them. They’re the most common star in the galaxy, comprising an estimated 75 percent of the Milky Way’s hundreds of billions of stars. If Dressing’s estimates are right, then our galaxy could be teeming with 100 billion Earth-sized planets in their stars’ habitable zones.

To be sure, these estimates have lots of limitations. They depend on what you mean by the habitable zone, which isn’t well defined. Generally, the habitable zone is where it’s not too hot or too cold for liquid water to exist. But there are countless considerations, such as how well a planet’s atmosphere can retain water. With a more generous definition that widens the habitable zone, Petigura’s numbers for Earth-sized planets around a sun-like star go up to 22 percent or more. Likewise, Dressing’s numbers could also go up.
Astronomers were initially skeptical of M-dwarf systems because they thought a planet couldn’t be habitable near this kind of star. For one, M dwarfs are more active, especially during within the first billion years of its life. They may bombard a planet with life-killing ultraviolet radiation. They can spew powerful stellar flares that would strip a planet of its atmosphere.

And because a planet will tend to orbit close to an M dwarf, the star’s gravity can alter the planet’s rotation around its axis. When such a planet is tidally locked, as such a scenario is called, part of the planet may see eternal daylight while another part sees eternal night. The bright side would be fried while the dark side would freeze—hardly a hospitable situation for life.

But none of these are settled issues, and some studies suggest they may not be as big of a problem as previously thought, says astronomer Aomawa Shields of UCLA. For example, habitability may depend on specific types and frequency of flares, which aren’t well understood yet. Computer models have also shown that an atmosphere can help distribute heat, preventing the dark side of a planet from freezing over.

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Astronomers Have Discovered Eight Potentially Habitable Planets

January 7, 2015 / / 0 Comments


Credit: David A. Aguilar (CfA)


Excerpt from  forbes.com

Astronomers have announced that they have discovered eight more planets that likely exist in temperature ranges where life could exist.

The astronomers began their research path by examining candidates for planets that had been identified by NASA’s Kepler mission. The candidates were analyzed using a supercomputer running algorithms at NASA’s Ames facility.

After exploring the statistical likelihood of the planets’ existence, the team followed up with months of observations using a variety of different methods. The planets are distant enough, however, that their habitabiliy is still only a likelihood, not a certainty.

“We don’t know for sure whether any of the planets in our sample are truly habitable,” researcher David Kipping said in a statement. “All we can say is that they’re promising candidates.”

The two most potentially Earth-like planets of the group of eight are Kepler-438b and Kepler-442b, both of which circle red dwarf stars are are respectively 70% and 97% likely to be in the habitable temperature zones of their respective stars. However, it should be noted that there are serious issues regarding the potential habitability of planets circling red dwarf stars, so confirmation will require significantly more study.

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Age of stars can now be pinned to their spin

January 6, 2015 / / 0 Comments

Excerpt from bbc.comAstronomers have proved that they can accurately tell the age of a star from how fast it is spinning. We know that stars slow down over time, but until recently there was little data to support exact calculations. For ...

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