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A new technique for studying exoplanet atmospheres could make it possible for scientists to get a close look at the atmosphers of planets like Proxima b in the 2020s.

A newly proposed technique could make it possible to search for life on alien planets much sooner than scientists had expected.  

Earlier this year, scientists discovered a planet orbiting the nearest star to Earth's own sun. Although relatively little is known about this newly discovered planet, which was dubbed Proxima b, evidence suggests it's possible that it has the right conditions to support life.

Of course, scientists are eager to look for signs of life on Proxima b (and members of the general public are eager to hear the results). But a deep look at the planet's atmosphere, where signs of life might hide, might require massive, next-generation, space-based telescopes that aren't expected to get off the ground until at least the 2030s. [Giant Space Telescopes of the Future (Infographic)]

But now, at least two different groups of astronomers are investigating a method for doing atmospheric studies of Proxima b — and other, possibly habitable planets like it — using ground-based telescopes that are scheduled to come online in the 2020s, significantly cutting down on the wait time.

Vermin of the sky

Thousands of planets have been identified around stars other than our own, a majority of them in the past six years, thanks to the dedicated Kepler space telescope (although many other observatories have contributed to this exoplanet treasure trove).

But finding planets is much different from characterizing their properties — things such as a planet's mass and diameter; whether it is made of rock or primarily of gas; its surface temperature; whether it has an atmosphere; and what that atmosphere is composed of.  

Earlier this month, at a workshop hosted by the National Academy of Sciences that explored the search for life beyond Earth, Matteo Brogi, a Hubble fellow at the University of Colorado, described a method for studying the atmosphere of Proxima b using next-generation ground-based telescopes.

The approach could be applied to other planets that, like Proxima b, are rocky, and orbit in the habitable zone of relatively cool stars, known as red dwarfs. The astronomical community is already emphasizing the search for "Earth-like" planets around these small stars because the latter are incredibly common in the galaxy; astronomers have even jokingly referred to red dwarfs as the "vermin of the sky."

"The frequency of small planets around small stars is extremely high; on average, there are about 2.5 planets per star," Brogi said. "Regarding habitable planets around small stars, there should be more or less a frequency of close to 30 percent. So every three stars should have a habitable planet."

An accordion of light

The approach Brogi and his colleagues are investigating would combine two different techniques for studying stars and exoplanets. The first is an extremely common technique in astronomy called high-resolution spectroscopy, which essentially looks at light from an object in extremely fine detail.

To understand high-resolution spectroscopy, consider the way sunlight passes through a prism and produces a rainbow; the glass takes the light and fans it out like an accordion, revealing that the whitish colored light is actually composed of various colors.

Spectroscopy spreads the light out even more — stretching that accordion out to unrealistic lengths for a musical instrument — revealing finer and finer detail about the colors (wavelengths) that are contained in the light from stars, planets and other cosmic objects. The resulting band of colors is called an object's spectrum.

The first scientists to use spectroscopy discovered something so amazing that, without it, the field of modern astronomy might be entirely unrecognizable: Chemical elements leave a unique fingerprint in the light spectrum. In other words, if a star is made of hydrogen and helium, those elements will leave a distinct signature on the light the star emits — when astronomers fan out the light from the star, they can see that signature in the wavelengths that are present or not present. This tool has allowed astronomers to learn about the composition of objects billions of light-years away, and helped to uncover the incredible fact that we are all made of stardust.

So if spectroscopy can be applied to the light coming from exoplanets, scientists might get a look at the composition of the planetary atmospheres. It's still unclear to scientists which atmospheric chemical mixtures would strongly indicate the presence of life — most plants on Earth consume carbon dioxide and produce oxygen, and other forms of life produce methane, so a combination with high levels of oxygen and methane might indicate the presence of biology. However, there are potential false positives and false negatives, not to mention potential life-forms that consume and produce different chemicals than living organisms on Earth.

But there are a couple of hurdles standing in the way of performing spectroscopy on a planet, and one of the biggest is that trying to see the light from a planet (which is fairly dim) when it is orbiting right next to a star (which is incredibly bright) is like trying to see the glow of a firefly against a backdrop of 1,000 stage spotlights (which would be difficult).

So Brogi and his colleagues have proposed a way to help separate those two sources of light. Because the planet is moving around the star, it is also moving toward, and then away from, the Earth throughout its orbit. When a source of light moves toward an observer, the light waves become compressed; when the source moves away from the observer, the light waves become stretched out. This is called the Doppler effect, or redshift. It also happens with sound waves, which is why when a police siren is moving toward you, it sounds like it is increasing in pitch; the waves get pushed together so that they literally have a higher frequency. When the car passes you and starts moving away, it sounds like the siren is getting lower in pitch, because the waves get stretched out and the frequency goes down.

The idea is that, out of the sea of light coming from a distant star, scientists could pick out the island of light coming from the planet by looking for the redshifted/Doppler shifted light. (This also could be used to separate any interference from Earth's own atmosphere.) Looking for those shifts in the light also falls under the header of spectroscopy.

Nonetheless, the Doppler shift approach wouldn't be powerful enough to work on its own, and this is where the second technique comes in: Astronomers would need to directly image the star or planet system first.

The planet-finding technique known as "direct imaging" is pretty much what it sounds like: an attempt to get a direct snapshot of both a planet and the star it orbits. To do this, scientists try to reduce the star's blinding glare enough so that they can see the light from the planet. It's a challenging method and one that can't be done for just any system — the planet has to be sufficiently bright compared to its parent star, which means most of the planets seen with direct imaging thus far are gas giants like Jupiter, and oriented in such a way that it can be viewed clearly from Earth. 

So Brogi and his colleagues proposed the method of first directly imaging the planetary system, using that image to locate the planet, and then further separating the planet's light from the star's light using the Doppler method. From there, they can use high-resolution spectroscopy to learn about the planet's atmosphere.

Telescopes currently in operation don't have the sensitivity to make this plan a reality, but some very large telescopes currently under development could. These scopes should be able to directly image smaller planets, as long as those planets are orbiting dimmer stars. Those include the Giant Magellan Telescope, scheduled to turn on around 2021, and the European Extremely Large Telescope, set to begin taking data as early as 2024. Direct imaging capabilities are likely to improve by leaps and bounds with these telescopes, but with direct imaging alone, it will likely not be possible to characterize many Earth-size, potentially habitable worlds.

During his talk, Brogi said there should be "on the order of 10" potentially habitable planets that this method could identify and study.

Challenges and progress

Brogi noted that there are caveats to the plan. For example, many of the predictions that he and his team made about how sensitive the method would be were "based on best-case scenarios," so dealing with real data will undoubtedly pose challenges. Moreover, the method compares the observed planetary spectra with laboratory experiments that recreate the expected spectra for various chemical elements, which means any errors in that laboratory work will carry over into the planet studies. But overall, Brogi said he and his colleagues think the approach could provide a better glimpse of the atmospheres of small, rocky, potentially habitable planets than scientists are likely to see for a few decades.

They aren't the only group that thinks so. Researchers based at the California Institute of Technology (Caltech) are investigating this approach as well, according to Dimitri Mawet, an associate professor of astronomy at Caltech. Mawet and his colleagues call the approach high dispersion coronagraphy (HDC) — a combination of high-resolution spectroscopy and high-contrast imaging techniques (direct imaging). (Similar lines of thought have been proposed by other groups.)

Mawet told Space.com in an email that he and his colleagues recently submitted two research papers that explore the "practical limits of HDC" and demonstrate "a promising instrument concept in the lab at Caltech." He said he and his colleagues plan to test the technique using the Keck telescope, located in Hawaii, "about two years from now," to study young, giant planets (so not very Earth-like). He confirmed that to use the technique to study small, rocky planets like Proxima b, scientists will have to wait for those next-generation, ground-based telescopes, like the Giant Magellan Telescope and the European Extremely Large Telescope. He also confirmed Brogi's estimation of "on the order of 10" rocky exoplanets in the habitable zone of their stars that could be studied using this technique.

"As [Brogi] mentioned, there are several caveats associated with the HDC technique," Mawet told Space.com. "However, we are working on addressing them and, in the process, studying the fundamental limits of the technique. Our initial results are very promising, and exciting."

Follow Calla Cofield@callacofield.Follow us@Spacedotcom,Facebook andGoogle+. Original article onSpace.com.

Categorized in Science & Tech

The wax worm, a caterpillar typically used for fishing bait and known for damaging beehives by eating their wax comb, has now been observed munching on a different material: plastic bags.

Scientist Federica Bertocchini of the Institute of Biomedicine and Biotechnology of Cantabria in Spain first noticed the wax worms’ plastic-eating skills when she was cleaning up a wax worm infestation in one of the beehives she keeps at home. She put the worms in a plastic bag, tied it closed, and put the bag in a room of her house while she finished cleaning the hive. When she returned to the room, “they were everywhere,” Bertocchini said in a statement. They’d escaped by chewing their way out of the bag, and fast.

“This project began there and then,” she said. In a paper published in Current Biology on Monday (April 24), Bertocchini and her colleagues described 100 wax worms chewing through a polyethylene shopping bag—the kind that people discard at a rate of 1 trillion per year globally—in around 40 minutes. After 12 hours, the bag was significantly shredded.

To make sure the worms weren’t just chewing through the plastic but actually eating it, the researchers pureed some worms and left the paste in contact with the plastic; after 14 hours, about 13% of the plastic was gone, suggesting that some compound in the worm’s digestive system was truly digesting the bag. The researchers also scanned the chewed-up bags for residue, and found ethylene glycol—the main compound in antifreeze—was left behind, “confirming [polyethylene] degradation.”

A wax worm chewing a hole through plastic, covered in polyethylene debris
 

Once in a landfill, polyethylene plastic shopping bags don’t break down for a really, really long time—some researchers estimate bags and other polyethylene packaging could take between 100 and 400 years to degrade naturally. That has prompted a search for a biological “digestor” to speed up plastic degradation; In 2011, researchers found a fungus that could erode polyurethane, another common plastic piling up in trash heaps and oceans globally.

Another research team in 2014 found that bacteria within wax worms’ digestive systems could begin to degrade polyethylene after about two months. But Bertocchini’s worms did a lot more damage, a lot faster.

While the discovery is far from an actionable solution to plastic waste (worms would not be able to survive in the zero-oxygen environment of a landfill, for example) Bertocchini told Ed Yong at the Atlantic she hopes to find the enzyme the worms use to break down the plastic: “Maybe we can find the molecule and produce it at high-scale rather than using a million worms in a plastic bag.”

Wax worm eats through plastic
© Provided by Quartz Wax worm eats through plastic

This article was published on msn.com 

Categorized in Science & Tech

Over the holidays it's best to avoid any arguments, whenever possible. But if you can't, you may want to bring some scientific ammunition for your side of the discussion.

It turns out that if you want to convince someone that your explanation for something is the best way to explain it, you might want to tack on some useless (though accurate) information from a tangentially related scientific field.

It turns out that when you tack on additional information from a respected field of study, people think that makes an explanation more credible.

That strategy can be devised from the findings of a recent study conducted by University of Pennsylvania researchers that was published in the journal Cognition.

And while this is a new finding, it's just one of several cognitive biases we have in favor of certain types of explanations. We think longer explanations are better than short ones and we prefer explanations that point to a goal or a reason for things happening, even if these things don't actually help us understand a phenomenon.

As the authors behind this most recent paper note, previous research has also shown that we prefer explanations of psychology when they contain "logically irrelevant neuroscience information," something known as the "seductive lure effect."

As former Tech Insider correspondent Drake Baer put it covering an earlier study on the same topic, "if you're trying to explain why someone did something, you can count on neurobabble to make you sound more convincing." All those references to the brain sound like they can really explain the ways our minds work, even if neuroscience is still a field we know little about.

human brain connectome

Explanations that refer to what's going in in the brain are super appealing. Human Connectome Project, Science, March 2012.

But until now, researchers haven't known if this argument-winning strategy was limited to using neuroscience to "explain" psychology or if it could be used to explain other areas of science as well. The UPenn team theorized people might in general prefer arguments that refer to more fundamental science, even if those references don't contribute to the explanation. They call this type of argument a reductive explanation (reducing one science to more fundamental parts).

To test this theory, the researchers created a hierarchy of sciences, going from least to most fundamental: social science, psychology, neuroscience, biology, chemistry, and finally physics. They recruited undergraduate students and people from Amazon's Mechanical Turk work marketplace and presented them with a survey designed to figure out whether useless reductive information made them consider explanations "better."

In each case, the researchers offered four possible explanations for a scientific concept: a good explanation, a good explanation that included the additional reductive information, a bad explanation, and a bad explanation that included reductive information.

marco rubio donald trump debate

Should we add "used useless reductive information to support an argument" to debate bingo? REUTERS/Mike Stone

As a general rule, their hypothesis panned out — people think explanations that have useless information containing details about a more "fundamental" science are usually better.

But there are some interesting exceptions and additional takeaways here.

  • Good explanations matter, and were rated better than bad explanations (even if the bad explanations had reductive information).
  • Adding useless reductive information made the biggest difference when researchers added neuroscience to an explanation of psychological science.
  • Participants trusted psychology the least and — in the one exception to the general rule — didn't think adding psychological explanations to social science made those explanations more credible (though these particular findings weren't statistically significant).
  • Study participants actually considered neuroscience more rigorous and prestigious than the sciences considered more fundamental by researchers (biology, chemistry, and physics). This could explain the big effect that neuroscience explanation has when added to explanations of psychological science.
  • Mechanical Turk respondents thought the explanations with reductive information were better than undergraduates thought they were. That information made a big significant difference for them, but it was less of a big deal for undergraduates. Different groups of people are going to evaluate information in different ways, and neither of these groups of people can accurately represent the way the entire population evaluates information.
  • People who were better at logical reasoning were better at evaluating explanation accurately (they gave less credence to reductive information). The researchers think this could mean that philosophers who have studied logic are less susceptible to this cognitive bias.
  • People who knew more about science were also better at telling good explanations from bad explanations.

So the next time you read an explanation of something, check to see if the author is adding useless information to support an argument, making you more inclined to believe them for all the wrong reasons.

And if you want to convince someone of something, you can see if adding some background scientific details helps sway the argument your way. Just try to rely on a science other than psychology.

 

Author: Kevin Loria
Source: http://www.businessinsider.com/how-to-convince-people-of-something-2016-12

Categorized in Science & Tech

A team of astronomers from several corners of the globe just discovered a massive collection of galaxies that they didn’t even know was there. That wouldn’t normally be anything out of the ordinary — after all, scientists find new things in space all the time — but what makes this discovery particularly special is that the the giant cluster is actually pretty close to us, relatively speaking.

It’s called the Vela supercluster, and it might be the largest structure in the known universe, measuring a massive 370 million light years across, and up until now it was hidden from the view of scientists. Our view was obscured by the huge clouds of dust and gas that exist in our home galaxy of the Milky Way, and its existence game as a surprise to even the most seasoned star gazers.

“This is one of the biggest concentrations of galaxies in the Universe – possibly the biggest in the neighbourhood of our Galaxy, but that will need to be confirmed by further study,” said Matthew Colless, Professor at ANU Research School of Astronomy and Astrophysics said of the discovery.

“I could not believe such a major structure would pop up so prominently,” Professor Renée Kraan-Korteweg, who has spent over a decade studying this particular region of space, noted.

But aside from just being there, the existence of the Vela supercluster could help to explain the behavior of our own Milky Way. Our galaxy’s has always moved slightly different than scientists would predict based on the arrangement of known nearby galaxies and clusters. Now, adding Vela into the mix might be the missing piece researchers didn’t even know they were looking for.

Author : Mike Wehner

Source : https://www.yahoo.com/tech/scientists-just-discovered-huge-cluster-galaxies-hidden-earth-001749943.html

Categorized in Science & Tech

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