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NASA’s Kepler program finds the most Earth-like planet yet

Pretty exciting news from the Kepler Radar Observatory on Thursday – in the form of Kepler-186f. That’s an Earth-like planet in its sun’s happy zone – not too far, not too close, but just the right distance zone to open the promise of life.

The Kepler Mission has been on the lookout via satellite for just such Read more →

a neighbor in the Milky Way. Here’s a look at what some very excited scientists rolled out in the announcement:

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Astronomers have discovered what they say is the most Earth-like planet yet detected — a distant, rocky world that’s similar in size to our own and exists in the Goldilocks zone where it’s not too hot and not too cold for life.

The find, announced Thursday, excited planet hunters who have been scouring the Milky Way galaxy for years for potentially habitable places outside our solar system.

“This is the best case for a habitable planet yet found. The results are absolutely rock solid,” University of California, Berkeley astronomer Geoff Marcy, who had no role in the discovery, said in an email.

The planet was detected by NASA’s orbiting Kepler telescope, which examines the heavens for subtle changes in brightness that indicate an orbiting planet is crossing in front of a star. From those changes, scientists can calculate a planet’s size and make certain inferences about its makeup.

The newfound object, dubbed Kepler-186f, circles a red dwarf star 500 light-years from Earth in the constellation Cygnus. A light-year is almost 6 trillion miles.

The planet is about 10 percent larger than Earth and may very well have liquid water — a key ingredient for life — on its surface, scientists said. That is because it resides at the outer edge of the habitable temperature zone around its star — the sweet spot where lakes, rivers or oceans can exist without freezing solid or boiling away.

The planet probably basks in an orange-red glow from its star and is most likely cooler than Earth, with an average temperature slightly above freezing, “similar to dawn or dusk on a spring day,” Marcy said.

The discovery was detailed in Friday’s issue of the journal Science.

View image on Twitter

 

Lead researcher Elisa Quintana at NASA’s Ames Research Center said she considers the planet to be more of an “Earth cousin” than a twin because it circles a star that is smaller and dimmer than our sun. While Earth revolves around the sun in 365 days, this planet completes an orbit of its star every 130 days.

“You have a birthday every 130 days on this planet,” she said.

Scientists cannot say for certain whether it has an atmosphere, but if it does, it probably contains a lot of carbon dioxide, outside experts said.

“Don’t take off your breathing mask if you ever land there,” said Lisa Kaltenegger, a Harvard and Max Planck Institute astronomer who had no connection to the research.

Despite the differences, “now we can point to a star and know that there really is a planet very similar to the Earth, at least in size and temperature,” Harvard scientist David Charbonneau, who was not part of the team, said in an email.

Since its launch in 2009, Kepler has confirmed 961 planets, but only a few dozen are in the habitable zone. Most are giant gas balls like Jupiter and Saturn, and not ideal places for life. Scientists in recent years have also found planets slightly larger than Earth in the Goldilocks zone called “super Earths,” but it is unclear if they are rocky.

The latest discovery is the closest in size to Earth than any other known world in the habitable region.

Kepler-186f is part of a system of five planets, all of which are roughly Earth’s size. However, the other planets are too close to their star to support life.

Astronomers may never know for certain whether Kepler-186f can sustain life. The planet is too far away even for next-generation space telescopes like NASA’s overbudget James Webb, set for launch in 2018, to study in detail.

Kepler completed its prime mission and was in overtime when one of the wheels that keep its gaze steady failed last year. NASA has not yet decided whether to keep using the telescope to hunt for planets on a scaled-back basis.

 

 

 

 

New study outlines ‘water world’ theory of life’s origins

Life took root more than four billion years ago on our nascent Earth, a wetter and harsher place than now, bathed in sizzling ultraviolet rays. What started out as simple cells ultimately transformed into slime molds, frogs, elephants, humans and the rest of our planet’s living kingdoms. How did it all begin?

A new study from researchers at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and the Icy Worlds team at NASA’s Astrobiology Institute, based at NASA’s Ames Research Center in Moffett Field, Calif., describes how electrical energy naturally produced at the sea floor might have given rise to life. While the scientists had already proposed this hypothesis — called “submarine alkaline hydrothermal emergence of life” — the new report assembles Read more →

decades of field, laboratory and theoretical research into a grand, unified picture.

According to the findings, which also can be thought of as the “water world” theory, life may have begun inside warm, gentle springs on the sea floor, at a time long ago when Earth’s oceans churned across the entire planet. This idea of hydrothermal vents as possible places for life’s origins was first proposed in 1980 by other researchers, who found them on the sea floor near Cabo San Lucas, Mexico. Called “black smokers,” those vents bubble with scalding hot, acidic fluids. In contrast, the vents in the new study — first hypothesized by scientist Michael Russell of JPL in 1989 — are gentler, cooler and percolate with alkaline fluids. One such towering complex of these alkaline vents was found serendipitously in the North Atlantic Ocean in 2000, and dubbed the Lost City.

“Life takes advantage of unbalanced states on the planet, which may have been the case billions of years ago at the alkaline hydrothermal vents,” said Russell. “Life is the process that resolves these disequilibria.” Russell is lead author of the new study, published in the April issue of the journal Astrobiology.

Other theories of life’s origins describe ponds, or “soups,” of chemicals, pockmarking Earth’s battered, rocky surface. In some of those chemical soup models, lightning or ultraviolet light is thought to have fueled life in the ponds.

The water world theory from Russell and his team says that the warm, alkaline hydrothermal vents maintained an unbalanced state with respect to the surrounding ancient, acidic ocean — one that could have provided so-called free energy to drive the emergence of life. In fact, the vents could have created two chemical imbalances. The first was a proton gradient, where protons — which are hydrogen ions — were concentrated more on the outside of the vent’s chimneys, also called mineral membranes. The proton gradient could have been tapped for energy — something our own bodies do all the time in cellular structures called mitochondria.

The second imbalance could have involved an electrical gradient between the hydrothermal fluids and the ocean. Billions of years ago, when Earth was young, its oceans were rich with carbon dioxide. When the carbon dioxide from the ocean and fuels from the vent — hydrogen and methane — met across the chimney wall, electrons may have been transferred. These reactions could have produced more complex carbon-containing, or organic compounds — essential ingredients of life as we know it. Like proton gradients, electron transfer processes occur regularly in mitochondria.

“Within these vents, we have a geological system that already does one aspect of what life does,” said Laurie Barge, second author of the study at JPL. “Life lives off proton gradients and the transfer of electrons.”

As is the case with all advanced life forms, enzymes are the key to making chemical reactions happen. In our ancient oceans, minerals may have acted like enzymes, interacting with chemicals swimming around and driving reactions. In the water world theory, two different types of mineral “engines” might have lined the walls of the chimney structures.

“These mineral engines may be compared to what’s in modern cars,” said Russell.

“They make life ‘go’ like the car engines by consuming fuel and expelling exhaust. DNA and RNA, on the other hand, are more like the car’s computers because they guide processes rather than make them happen.”

One of the tiny engines is thought to have used a mineral known as green rust, allowing it to take advantage of the proton gradient to produce a phosphate-containing molecule that stores energy. The other engine is thought to have depended on a rare metal called molybdenum. This metal also is at work in our bodies, in a variety of enzymes. It assists with the transfer of two electrons at a time rather than the usual one, which is useful in driving certain key chemical reactions.

“We call molybdenum the Douglas Adams element,” said Russell, explaining that the atomic number of molybdenum is 42, which also happens to be the answer to the “ultimate question of life, the universe and everything” in Adams’ popular book, “The Hitchhiker’s Guide to the Galaxy.” Russell joked, “Forty-two may in fact be one answer to the ultimate question of life!”

The team’s origins of life theory applies not just to Earth but also to other wet, rocky worlds.

“Michael Russell’s theory originated 25 years ago and, in that time, JPL space missions have found strong evidence for liquid water oceans and rocky sea floors on Europa and Enceladus,” said Barge. “We have learned much about the history of water on Mars, and soon we may find Earth-like planets around faraway stars. By testing this origin-of-life hypothesis in the lab at JPL, we may explain how life might have arisen on these other places in our solar system or beyond, and also get an idea of how to look for it.”

For now, the ultimate question of whether the alkaline hydrothermal vents are the hatcheries of life remains unanswered. Russell says the necessary experiments are jaw-droppingly difficult to design and carry out, but decades later, these are problems he and his team are still happy to tackle.

The California Institute of Technology in Pasadena manages JPL for NASA.

 

 

 

Source: sciencedaily

Here’s how you can see tonight’s total lunar eclipse and “blood moon”.

 

So, you want to see a total lunar eclipse? Then plan to stay up late tonight and cross your fingers that clouds aren’t in the way, because if you’re in North America this could be your last chance to see one this clearly until 2019.

Monday night is the first of four consecutive total eclipses, at six-month intervals, that will also bring a “blood moon” into the night sky. Tonight’s event begins at around 2:00 a.m. EDT and should be visible from both Read more →

North and South America.

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The remaining total lunar eclipses of the set — known as a tetrad — will occur on October 8, 2014; April 4, 2015; and September 28, 2015.

One stunning feature of tonight’s eclipse will be the blood-red moon lighting the night sky — and no, it’s not a sign of the apocalypse, as some doomsdayers believe; the burnt-orange appearance is created by light dispersion. (Astronomers rarely use the term “blood moon”; a red moon is usually called a “Hunter’s Moon.”)

Astronomer Fred Espenak explains that the moon could take on “a dramatically colorful appearance, ranging from bright orange to blood red,” while NASA gives a more poetic explanation:

“Imagine yourself standing on a dusty lunar plain looking up at the sky. Overhead hangs Earth, nightside down, completely hiding the sun behind it. The eclipse is underway.

You might expect Earth seen in this way to be utterly dark, but it’s not. The rim of the planet is on fire! As you scan your eye around Earth’s circumference, you’re seeing every sunrise and every sunset in the world, all of them, all at once. This incredible light beams into the heart of Earth’s shadow, filling it with a coppery glow and transforming the Moon into a great red orb.”

Space.com estimates that around 922 million people worldwide will be able to see tonight’s total lunar eclipse. If it’s too cloudy to watch from home, you can tune intoNASA’s livestream.

Tonight is also the chance to see Mars up close when it passes within 57 million miles of Earth, its closest approach in six years.

 

 

 

 

Source: discovery.com

Odds that global warming is due to natural factors

An analysis of temperature data since 1500 all but rules out the possibility that global warming in the industrial era is just a natural fluctuation in the earth’s climate, according to a new study by McGill University physics professor Shaun Lovejoy.

The study, published online April 6 in the journalClimate Dynamics, represents a new approach to the question of whether global warming in the industrial era has been caused largely by man-made emissions from the burning of fossil fuels. Rather than using complex computer models to estimate the effects of greenhouse-gas emissions, Lovejoy Read more →

examines historical data to assess the competing hypothesis: that warming over the past century is due to natural long-term variations in temperature.

“This study will be a blow to any remaining climate-change deniers,” Lovejoy says. “Their two most convincing arguments – that the warming is natural in origin, and that the computer models are wrong – are either directly contradicted by this analysis, or simply do not apply to it.”

Lovejoy’s study applies statistical methodology to determine the probability that global warming since 1880 is due to natural variability. His conclusion: the natural-warming hypothesis may be ruled out “with confidence levels great than 99%, and most likely greater than 99.9%.”

To assess the natural variability before much human interference, the new study uses “multi-proxy climate reconstructions” developed by scientists in recent years to estimate historical temperatures, as well as fluctuation-analysis techniques from nonlinear geophysics. The climate reconstructions take into account a variety of gauges found in nature, such as tree rings, ice cores, and lake sediments. And the fluctuation-analysis techniques make it possible to understand the temperature variations over wide ranges of time scales.

For the industrial era, Lovejoy’s analysis uses carbon-dioxide from the burning of fossil fuels as a proxy for all man-made climate influences – a simplification justified by the tight relationship between global economic activity and the emission of greenhouse gases and particulate pollution, he says. “This allows the new approach to implicitly include the cooling effects of particulate pollution that are still poorly quantified in computer models,” he adds.

While his new study makes no use of the huge computer models commonly used by scientists to estimate the magnitude of future climate change, Lovejoy’s findings effectively complement those of the International Panel on Climate Change (IPCC), he says. His study predicts, with 95% confidence, that a doubling of carbon-dioxide levels in the atmosphere would cause the climate to warm by between 2.5 and 4.2 degrees Celsius. That range is more precise than – but in line with — the IPCC’s prediction that temperatures would rise by 1.5 to 4.5 degrees Celsius if CO2 concentrations double.

“We’ve had a fluctuation in average temperature that’s just huge since 1880 – on the order of about 0.9 degrees Celsius,” Lovejoy says. “This study shows that the odds of that being caused by natural fluctuations are less than one in a hundred and are likely to be less than one in a thousand.

“While the statistical rejection of a hypothesis can’t generally be used to conclude the truth of any specific alternative, in many cases – including this one – the rejection of one greatly enhances the credibility of the other.”

 

 

 

Source: sciencedaily

Hepatitis C treatment cures over 90 percent of patients with cirrhosis

Twelve weeks of an investigational oral therapy cured hepatitis C infection in more than 90 percent of patients with liver cirrhosis and was well tolerated by these patients, according to an international study that included researchers from UT Medicine San Antonio and the Texas Liver Institute. Historically, hepatitis C cure rates in patients with cirrhosis (liver scarring) have been lower than 50 percent and the treatment was not safe for many of these patients.

Hepatitis C virus is the No. 1 driver of cirrhosis, liver transplants and liver cancer in the United States, noted Fred Poordad, M.D., lead author on the study, which was released Saturday by The New England Journal of Medicine in conjunction with Dr. Poordad’s presentation of the data at the International Liver Congress in Read more →

London. UT Medicine is the clinical practice of the School of Medicine at The University of Texas Health Science Center at San Antonio, where Dr. Poordad is a professor of medicine. He is vice president of the Texas Liver Institute in San Antonio.

Interferon previously was the only agent to show effectiveness against hepatitis C, but patients often relapsed and the therapy caused multiple side effects. The new regimen is interferon-free and consists of several agents — ABT-450/ritonavir, ombitasvir, dasabuvir and ribavirin. Twelve weeks after the last dose, no hepatitis C virus was detected in the bloodstream of 91.8 percent of patients who took the pills for 12 weeks. Among patients treated for 24 weeks, 95.9 percent were virus-free 12 weeks after the end of therapy.

“These are out-of-the-ballpark response rates, not on the same planet as interferon,” Dr. Poordad said. “The reason this study is so profound is because interferon is not tolerated nor is it safe in many people with cirrhosis. Many of the patients with cirrhosis in this study were not even eligible to be treated with interferon.”

One of those patients was retired San Antonio anesthesiologist Sergio Buentello, M.D. Diagnosed with hepatitis C infection 11 years ago, Dr. Buentello had treatment with side effects and no cure eight years ago. “My viral count came down, but never to zero,” he said.

When Eric Lawitz, M.D., of the Texas Liver Institute told him of the possibility of treatment with the new therapy, Dr. Buentello said he was skeptical. But as for so many others, the therapy worked.

“I feel very lucky to be living in this time, because I was almost resigned to the idea that I could never be cured,” Dr. Buentello said.

The study examined outcomes in 380 patients at 78 sites, including hospitals and centers in Spain, Germany, England, Canada and the U.S. The biopharmaceutical company AbbVie provided support.

Investigators are cataloging patient blood samples for three years after therapy and so far have noticed no long-term, late relapses, Dr. Poordad said.

“Patients with advanced liver disease can now be cured of their hepatitis with a very well-tolerated and short regimen,” he said.

The combination medication regimen is expected to be on the market as early as the end of 2014 or very early 2015.

 

 

Source: sciencedaily

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