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  • Giant group of octopus moms discovered in the deep sea
    Dienstag, 24.04.2018, 01:01:47 Uhr
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    Giant group of octopus moms discovered in the deep sea Chicago IL (SPX) Apr 19, 2018 -
    We know more about the surface of the moon that we do about the bottom of the ocean. The sea floor is an alien landscape, with crushing pressure, near-total darkness, and fluids wafting from cracks in the Earth's crust. It's also home to some weird animals that scientists are only just getting to know. Case in point: deep-sea expeditions and drones have revealed a giant group of octopuses and their eggs in a place where they shouldn't be able to survive."When I first saw the photos, I was like 'No, they shouldn't be there! Not that deep and not that many of them," says Janet Voight, associate curator of zoology at the Field Museum and an author of a new study on the octopuses published in Deep Sea Research Part I.Nearly two miles deep in the ocean, a hundred miles off the Pacific coast of Costa Rica, scientists during two cruises a year apart used subsea vehicles to explore the Dorado Outcrop, a rocky patch of sea floor made of cooled and hardened lava from an underwater volcano. Geochemists explored the outcrop in a tiny submersible vehicle, hoping to collect samples of the warm fluids that emerge from cracks in the rocks; they didn't count on finding dozens of octopuses huddled around the cracks.The octopuses were an unknown species of the genus Muusoctopus - pink, dinner-plate-sized creatures with enormous eyes. Up to a hundred of them seemed to occupy every available rock in a small area. That in itself was strange - Muuscoctopus are normally loners. Stranger still was that nearly all of the octopuses seemed to be mothers, each guarding a clutch of eggs. And this nursery was situated alongside the warm fluid issuing from the cracks in the outcrop.It doesn't make sense for deep-sea octopuses to brood eggs in warm water like this: it's suicide. Deep sea octopus live in cold, nearly invariant temperatures. Exposure to higher temperatures jump-starts their metabolism, making them need more oxygen than the warm water can provide.The octopuses that the scientists observed (both in-person and via hours of video footage from an ROV) showed evidence of severe stress, and they could only guess that the 186 eggs that were attached to the rocks leaking warm, low oxygen fluid had it worse. None had any sign of a developing embryo. All in all, not a great place to start an octopus family.However, the sheer number of what the scientist think are doomed octopuses and their eggs suggest that there's a better, healthier habitat nearby. The team suspects there must be more octopuses living inside crevices in the rocks, where the water is cool and rich in oxygen. The crevices could be such a good environment for egg-brooding that the booming population has to spill over into the dangerously warm region outside, like a gentrifying neighborhood expanding into a rougher part of town."Octopus females only produce one clutch of eggs in their lives. In order for this huge population to be sustained, there must be even more octopuses to replace the dying mothers and eggs that we can see," says Voight."My coauthors, Geoff Wheat and Anne Hartwell, know about basalt and how an outcrop like this is made. Odds are it has hollow areas where other females nurture their eggs to hatching. They are analogous to the boomers who have all the good jobs, while the millennials wait, seeking just one little piece of the cool rock." Voight notes that there's evidence for the unseen population: the scientists observed octopus arms emerging once in a while from cracks in the rock.The study doesn't just shed light upon deep-sea biology; it also illustrates the collaborative nature of science."This project was a cohesive dynamic of three scientists from different research backgrounds coming together to investigate a fascinating observation," says Hartwell, the paper's lead author and an oceanographer affiliated with the University of Akron and the University of Alaska Fairbanks."The focus of [our] expeditions to Dorado Outcrop was to study a cool hydrothermal system. In doing so, we discovered this fascinating congregation of brooding octopuses," says Wheat, a geochemist at the University of Alaska Fairbanks."To maximize the scientific return of the expeditions, we shared the video with deep-sea biologists, whose research led to this publication. This is only the third hydrothermal system of its type that has been sampled, yet millions of similar environments exist in the deep sea. What other remarkable discoveries are waiting for us?""These surprising observations show us how a deep-sea animal reproduces," says Barbara Ransom, a program director in the National Science Foundation's Division of Ocean Sciences, which funded the research."The findings were serendipitous. The researchers saw something unusual and stopped to find out what was happening. Unexpected discoveries like this one can dramatically change our understanding of how the oceans work.""To my knowledge there had been no reports of octopuses at this or comparable depths off between southern California and Peru. Never would I have anticipated such a dense cluster of these animals at 3000 meters depth, and we argue that the numbers of octopuses we see are simply the surplus population," says Voight."What else is down there that we can't even imagine? I want to find out."Research paper
  • Are we alone? NASA's new planet hunter aims to find out
    Dienstag, 24.04.2018, 01:01:47 Uhr
    Are we alone? NASA's new planet hunter aims to find out Tampa (AFP) April 16, 2018 -
    SpaceX postponed the launch of NASA's new planet-hunting mission Monday in order to verify the Falcon 9 rocket's navigation systems, the California-based company said.The next opportunity to blast off the $337 million satellite -- which aims to advance the search for extraterrestrial life by scanning the skies for nearby, Earth-like planets -- will be Wednesday.The Transiting Exoplanet Survey Satellite, or TESS, is "in excellent health and remains ready for launch," SpaceX said on Twitter."Launch teams are standing down today to conduct additional guidance navigation and control analysis."The postponement was announced about two hours before the planned blast off from a NASA launchpad in Cape Canaveral, Florida.The washing machine-sized spacecraft is built to search the nearest, brightest stars for signs of periodic dimming. These so-called "transits" may mean that planets are in orbit around them.TESS is expected to reveal 20,000 planets beyond our solar system, known as exoplanets, NASA said.Its discoveries will be studied further by ground- and space-based telescopes for signs of habitability, including rocky terrain, a size similar to Earth and a distance from their sun -- neither too close nor too far -- that allows the right temperature for liquid water.NASA predicts that TESS could find more than 50 Earth-sized planets and up to 500 planets less than twice the size of the Earth.TESS will survey far more cosmic terrain than its predecessor, NASA's Kepler Space Telescope, which launched in 2009, taking in some 85 percent of the skies."TESS is equipped with four very sensitive cameras that will be able to monitor nearly the entire sky," said George Ricker, TESS principal investigator at the Massachusetts Institute of Technology (MIT)."That is about 20 times what the Kepler mission was able to detect."- Kepler vs TESS -
    Kepler, the first planet-hunting mission of its kind, "was launched to answer one single question: How common is a planet like Earth around a star like the Sun?" said Patricia "Padi" Boyd, director of the TESS guest investigator program at NASA's Goddard Spaceflight Center."It was designed to look at 150,000 stars in a fairly wide field of view without blinking, for four years," she told reporters on the eve of the launch."One of the many amazing things that Kepler told us is that planets are everywhere and there are all kinds of planets out there."So TESS takes the next step. If planets are everywhere, then it is time for us to find the planets that are closest to us orbiting bright nearby stars, because these will be the touchstone system."TESS and Kepler use the same system of detecting planetary transits, or shadows cast as they pass in front of their star.While Kepler confirmed some 2,300 exoplanets and thousands more potential planet candidates, many were too distant and dim to be studied further.With Kepler running low on fuel and nearing the end of its life, TESS aims to pick up the search while focusing closer, on planets dozens to hundreds of light years away."TESS is going to dramatically increase the number of planets that we have to study," said Ricker.The Hubble Space Telescope and the James Webb Space Telescope, scheduled to launch in 2020, should be able to reveal more about planets' mass, density and the makeup of their atmosphere -- all clues to habitability.The first data from TESS is expected to be made public in July, and NASA says citizen astronomers are welcome to help study the planets.It may be decades before astronomers know whether or not life exists elsewhere."TESS is the first step," said Stephen Rinehart, TESS project scientist at NASA's Goddard Spaceflight Center.
  • We think we're the first advanced earthlings - but how do we really know?
    Dienstag, 24.04.2018, 01:01:47 Uhr
    We think we're the first advanced earthlings - but how do we really know? Rochester UK (SPX) Apr 18, 2018 -
    Imagine if, many millions of years ago, dinosaurs drove cars through cities of mile-high buildings. A preposterous idea, right? Over the course of tens of millions of years, however, all of the direct evidence of a civilization - its artifacts and remains - gets ground to dust. How do we really know, then, that there weren't previous industrial civilizations on Earth that rose and fell long before human beings appeared?It's a compelling thought experiment, and one that Adam Frank, a professor of physics and astronomy at the University of Rochester, and Gavin Schmidt, the director of the NASA Goddard Institute for Space Studies, take up in a paper published in the International Journal of Astrobiology."Gavin and I have not seen any evidence of another industrial civilization," Frank explains. But by looking at the deep past in the right way, a new set of questions about civilizations and the planet appear: What geological footprints do civilizations leave?Is it possible to detect an industrial civilization in the geological record once it disappears from the face of its host planet? "These questions make us think about the future and the past in a much different way, including how any planetary-scale civilization might rise and fall."In what they deem the "Silurian Hypothesis," Frank and Schmidt define a civilization by its energy use. Human beings are just entering a new geological era that many researchers refer to as the Anthropocene, the period in which human activity strongly influences the climate and environment.In the Anthropocene, fossil fuels have become central to the geological footprint humans will leave behind on Earth.By looking at the Anthropocene's imprint, Schmidt and Frank examine what kinds of clues future scientists might detect to determine that human beings existed. In doing so, they also lay out evidence of what might be left behind if industrial civilizations like ours existed millions of years in the past.Human beings began burning fossil fuels more than 300 years ago, marking the beginnings of industrialization. The researchers note that the emission of fossil fuels into the atmosphere has already changed the carbon cycle in a way that is recorded in carbon isotope records. Other ways human beings might leave behind a geological footprint include:Global warming, from the release of carbon dioxide and perturbations to the nitrogen cycle from fertilizersAgriculture, through greatly increased erosion and sedimentation rates
    Plastics, synthetic pollutants, and even things such as steroids, which will be geochemically detectable for millions, and perhaps even billions, of yearsNuclear war, if it happened, which would leave behind unusual radioactive isotopes"As an industrial civilization, we're driving changes in the isotopic abundances because we're burning carbon," Frank says. "But burning fossil fuels may actually shut us down as a civilization. What imprints would this or other kinds of industrial activity from a long dead civilization leave over tens of millions of years?"The questions raised by Frank and Schmidt are part of a broader effort to address climate change from an astrobiological perspective, and a new way of thinking about life and civilizations across the universe. Looking at the rise and fall of civilizations in terms of their planetary impacts can also affect how researchers approach future explorations of other planets."We know early Mars and, perhaps, early Venus were more habitable than they are now, and conceivably we will one day drill through the geological sediments there, too," Schmidt says. "This helps us think about what we should be looking for."Schmidt points to an irony, however: if a civilization is able to find a more sustainable way to produce energy without harming its host planet, it will leave behind less evidence that it was there."You want to have a nice, large-scale civilization that does wonderful things but that doesn't push the planet into domains that are dangerous for itself, the civilization," Frank says. "We need to figure out a way of producing and using energy that doesn't put us at risk."That said, the earth will be just fine, Frank says. It's more a question of whether humans will be.Can we create a version of civilization that doesn't push the earth into a domain that's dangerous for us as a species?"The point is not to 'save the earth,'" says Frank. "No matter what we do to the planet, we're just creating niches for the next cycle of evolution. But, if we continue on this trajectory of using fossil fuels and ignoring the climate change it drives, we human beings may not be part of Earth's ongoing evolution."
  • Newly discovered salty subglacial lakes could help search for life in solar system
    Dienstag, 24.04.2018, 01:01:47 Uhr
    Newly discovered salty subglacial lakes could help search for life in solar system Austin TX (SPX) Apr 13, 2018 -
    Researchers from the University of Texas Institute for Geophysics (UTIG) have helped discover the first subglacial lakes ever found in the Canadian High Arctic.The two new lakes are a potential habitat for microbial life and may assist scientists in the search for life beyond Earth. The findings, published in the April 13 edition of Science Advances, were made possible by airborne radar data acquired by UTIG and NASA and represent a new collaboration between Canada and the United States.While there are more than 400 known subglacial lakes in the world, concentrated primarily in Antarctica with a few in Greenland, these are the first found in the Canadian Arctic. And unlike all the others - which are believed to contain freshwater - these two appear to consist of extremely salty water. All subglacial lakes are good analogues for life beyond Earth, but the hypersaline nature of the Devon lakes makes them particularly tantalizing analogues for ice-covered moons in our solar system, researchers said.In 2011, researchers from UTIG showed that Jupiter's icy moon Europa, likely contains hypersaline lakes of liquid water within an ice shell that floats atop of a global ocean. The new lakes observed in Canada are very similar to these potential lakes locked inside Europa's icy shell.An analysis of radar data, show that the lakes discovered in Canada are located beneath 550 to 750 meters of ice underneath the Devon Ice Cap, one of the largest ice caps in the Canadian Arctic. They are thought to be the first isolated hypersaline subglacial lakes in the world, having no contact with an outside environment for thousands of years."If there is microbial life in these lakes, it has likely been under the ice for at least 120,000 years, so it likely evolved in isolation," Rutishauser said. "If we can collect a sample of the water, we may determine whether microbial life exists, how it evolved, and how it continues to live in this cold environment with no connection to the atmosphere."By evaluating the airborne survey data and, eventually, samples from the lake, scientists can better prepare for NASA's forthcoming Europa Clipper mission, which plans to deploy similar remote sensing techniques to characterize Europa's ice shell, said co-author Donald Blankenship, a UTIG senior research scientist. Blankenship is leading the development of the ice penetrating radar sounder for the Clipper mission, an instrument very similar to the one used to discover the Canadian lakes.Researchers with Montana State University, Stanford University, and the Cambridge University Scott Polar Research Institute also worked on the project. In addition to Blankenship, UTIG researchers Jamin Greenbaum, Cyril Grima and Duncan Young worked on the study. UTIG is a research unit of the UT Jackson School of Geosciences.The same research team is currently planning a return to the Canadian Arctic in spring 2018 for additional data acquisition over the lake area and surrounding ice caps with support from Canada's W. Garfield Weston Foundation."It's amazing how the trilateral collaboration between Canadian, U.S. and UK universities to understand ice cap response to climate change evolved into a paradigm shift in our perspective on potential terrestrial analogs for extraterrestrial habitats," Blankenship said.Lead author Anja Rutishauser is a Ph.D. student at the University of Alberta who will join The University of Texas at Austin as a postdoctoral fellow when she finishes her degree.
  • Scientists blast iron with lasers to study the cores of rocky exoplanets
    Dienstag, 24.04.2018, 01:01:47 Uhr
    Scientists blast iron with lasers to study the cores of rocky exoplanets Washington (UPI) Apr 17, 2018 -

    By blasting a small iron sample with high-powered lasers at the Lawrence Livermore National Laboratory, scientists can replicate the extreme pressure and density conditions found inside the cores of large, rocky exoplanets.

    The experiments have offered scientists unique insights into the core conditions found inside faraway super-Earths.

    "The discovery of large numbers of planets outside our solar system has been one of the most exciting scientific discoveries of this generation," Ray Smith, a physicist at LLNL, said in a news release. "These discoveries raise fundamental questions."

    "What are the different types of extrasolar planets and how do they form and evolve?" Smith said. "Which of these objects can potentially sustain surface conditions suitable for life? To address such questions, it is necessary to understand the composition and interior structure of these objects."

    Of the more than 4,000 confirmed and candidate exoplanets discovered by Kepler and other planet-hunters, the largest percentage are so-called super-Earths, rocky planets with a radius between and one and four times that of Earth.

    "Determining the interior structure and composition of these super-Earth planets is challenging but is crucial to understanding the diversity and evolution of planetary systems within our galaxy," Smith said.

    The larger the rocky exoplanet, the more intense the pressure found inside its core. Because iron is the most abundant compositional element inside super-Earths, scientists set out to study its properties under extreme pressure.

    Scientists used high-powered lasers and ramp compression techniques to replicate the extreme conditions. The laser at LLNL's National Ignition Facility can deliver 2 megajoules of laser energy over 30 nanoseconds, enough to compress the iron sample to 1.4 TPa, with a single TPa equaling 10 million atmospheres. That is four times the pressure achieved during previous experiments and the equivalent of the pressure found inside a rocky exoplanet with three to four times the mass of Earth.

    Researchers described the experiments this week in the journal Nature Astronomy.

    "Planetary interior models, which rely on a description of constituent materials under extreme pressures, are commonly based on extrapolations of low-pressure data and produce a wide range of predicated material states," Smith said. "Our experimental data provides a firmer basis for establishing the properties of a super-Earth planet with a pure iron planet."

    "Furthermore, our study demonstrates the capability for determination of equations of state and other key thermodynamic properties of planetary core materials at pressures well beyond those of conventional static techniques," he said. "Such information is crucial for advancing our understanding of the structure and dynamics of large rocky exoplanets and their evolution."
  • SPHERE Reveals Fascinating Zoo of Discs Around Young Stars - EMBARGO
    Dienstag, 24.04.2018, 01:01:47 Uhr
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    SPHERE Reveals Fascinating Zoo of Discs Around Young Stars - EMBARGO Munich, Germany (SPX) Apr 12, 2018 -
    New images from the SPHERE instrument on ESO's Very Large Telescope are revealing the dusty discs surrounding nearby young stars in greater detail than previously achieved. They show a bizarre variety of shapes, sizes and structures, including the likely effects of planets still in the process of forming.The SPHERE instrument on ESO's Very Large Telescope (VLT) in Chile allows astronomers to suppress the brilliant light of nearby stars in order to obtain a better view of the regions surrounding them. This collection of new SPHERE images is just a sample of the wide variety of dusty discs being found around young stars.These discs are wildly different in size and shape - some contain bright rings, some dark rings, and some even resemble hamburgers. They also differ dramatically in appearance depending on their orientation in the sky - from circular face-on discs to narrow discs seen almost edge-on.SPHERE's primary task is to discover and study giant exoplanets orbiting nearby stars using direct imaging. But the instrument is also one of the best tools in existence to obtain images of the discs around young stars - regions where planets may be forming. Studying such discs is critical to investigating the link between disc properties and the formation and presence of planets.Many of the young stars shown here come from a new study of T Tauri stars, a class of stars that are very young (less than 10 million years old) and vary in brightness. The discs around these stars contain gas, dust, and planetesimals - the building blocks of planets and the progenitors of planetary systems.These images also show what our own Solar System may have looked like in the early stages of its formation, more than four billion years ago.Most of the images presented were obtained as part of the DARTTS-S (Discs ARound T Tauri Stars with SPHERE) survey. The distances of the targets ranged from 230 to 550 light-years away from Earth. For comparison, the Milky Way is roughly 100 000 light-years across, so these stars are, relatively speaking, very close to Earth. But even at this distance, it is very challenging to obtain good images of the faint reflected light from discs, since they are outshone by the dazzling light of their parent stars.Another new SPHERE observation is the discovery of an edge-on disc around the star GSC 07396-00759, found by the SHINE (SpHere INfrared survey for Exoplanets) survey. This red star is a member of a multiple star system also included in the DARTTS-S sample but, oddly, this new disc appears to be more evolved than the gas-rich disc around the T Tauri star in the same system, although they are the same age. This puzzling difference in the evolutionary timescales of discs around two stars of the same age is another reason why astronomers are keen to find out more about discs and their characteristics.Astronomers have used SPHERE to obtain many other impressive images, as well as for other studies including the interaction of a planet with a disc, the orbital motions within a system, and the time evolution of a disc.The new results from SPHERE, along with data from other telescopes such as ALMA, are revolutionising astronomers' understanding of the environments around young stars and the complex mechanisms of planetary formation.Research Reports: "Disks Around T Tauri Stars With SPHERE (DARTTS-S) I: SPHERE / IRDIS Polarimetric Imaging of 8 Prominent T Tauri Disks" and "A new disk discovered with VLT/SPHERE around the M star GSC 07396-00759"
  • Once upon a time, an exoplanet was discovered
    Dienstag, 24.04.2018, 01:01:47 Uhr
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    Once upon a time, an exoplanet was discovered Washington DC (SPX) Apr 17, 2018 -
    In recent history, a very important achievement was the discovery, in 1995, of 51 Pegasi b, the first extrasolar planet ever found around a normal star other than the Sun.In a paper published in EPJ H, Davide Cenadelli from the Aosta Valley Astronomical Observatory (Italy) interviews Michel Mayor from Geneva Observatory (Switzerland) about his personal recollections of discovering this exoplanet.They discuss how the development of better telescopes made the discovery possible.They also delve into how this discovery contributed to shaping a new community of scholars pursuing this new field of research. In closing, they reflect upon the cultural importance that the 51 Pegasi b discovery had in terms of changing our view of the cosmos.Michel Mayor was born in Lausanne in 1942. He turned to astronomy when he did his PhD at the Geneva Observatory, where he focused on elucidating the theoretical nature of the spiral arms of galaxies, which make it possible for stars and nebulae to pass through without permanently remaining inside the arms.Later on his interest shifted to solar-type stars, and in 1991 he published the result of 15 years of work on the statistics of such solar-type stars.In hindsight, this paper played a significant role in boosting, at a later time, his interest in brown dwarfs and planets. He feels that the search for exoplanets was a direct continuation of that work.He then relates what drove the development of a spectrograph called ELODIE, designed to offer very high sensitivity in measuring the radial velocities of stars. ELODIE commenced operation in April 1994, and Mayor and his colleague Queloz discovered 51 Peg b in July 1995. As the first planet ever discovered around a normal star other than the Sun, it was a ground-breaking achievement.A few years later, Mayor contributed to designing and building another state-of-the-art spectrograph, called HARPS, that is now allowing astronomers to probe the universe further. Altogether about 300 new exoplanets have been discovered by Mayor and his co-workers since 51 Peg b.References: Michel Mayor and Davide Cenadelli (2018), Exoplanets: the beginning of a new era in astrophysics, Eur. Phys. Jour. H, DOI 10.1140/epjh/e2018-80063-1
  • NASA's newest planet-hunter, TESS, to survey the entire night sky
    Dienstag, 24.04.2018, 01:01:47 Uhr
    NASA's newest planet-hunter, TESS, to survey the entire night sky Washington DC (UPI) Apr 11, 2018 -

    With the crippled Kepler almost out of fuel, NASA is preparing the launch of its newest planet-hunting spacecraft, TESS.

    TESS, short for Transiting Exoplanet Survey Satellite, will be carried into space by SpaceX's Falcon 9 rocket on April 16. With a little help from the moon's gravity, the satellite will achieve a high Earth orbit, offering the probe wide, unobstructed views of the night sky. The probe will orbit Earth twice for every one lunar orbit.

    While TESS's scientific mission is largely the same as Kepler's -- image transiting exoplanets -- the probe will use a different approach. Whereas Kepler focused on small fields of view for long periods of time, TESS will take a wider, more comprehensive view.

    "TESS is designed to image almost all of the night sky -- using four wide angle cameras -- in long vertical strips called sectors," Natalia Guerrero, MIT scientist and researcher on the TESS mission, told UPI.

    TESS scientists have divided the sky into long strips called sectors. Each hemisphere contains 13 sectors, and over the next three years, TESS will survey, sector by sector, the Southern Hemisphere and then the Northern Hemisphere.

    During each sector scan, TESS's four cameras will capture 30-minute exposures. The four images will be stacked on top of each other by the satellite's computer and transmitted back to Earth.

    In addition to organizing the sky into sectors, TESS scientists have identified 200,000 especially bright stars likely to host transiting exoplanets. Each stellar target is highlighted by a so-called postage stamp.

    Exposures of each postage stamp will be stacked on top of each other every two minutes and beamed back to Earth. These postage stamp observations are expected to identify planetary systems located much closer to Earth than those found by Kepler.

    Data captured by TESS will go through the same image-processing pipeline used for Kepler observations. Basic algorithms will process images and identify the dimming patterns created when exoplanets pass across the face of their host star.

    Scientists will review the transit events identified via computer analysis and highlight targets for follow-up observations.

    "From the depth of the transit and the frequency light curve, we can back out the size of the planet and distance from its host star," Guerrero said.

    But, like Kepler, TESS is designed to survey the sky, not carry out in-depth investigations. Scientists will rely on other telescopes, both ground and space-based, to observe transiting objects in greater detail. Through follow-up investigations, astronomers will be able to estimate an exoplanet's mass and the composition of its atmosphere, as well as its habitability.

    TESS scientists will focus much of their analysis on the two-minute cadence of images of postage stamped targets, but the satellite's biggest surprises may be more likely to be revealed by the full frame images. In addition to capturing transits, the full-frame images will record observations of thousands of stars.

    "The full frame images will serve as really rich repositories of data," Guerrero said. "They will be made public and will be a wonderful opportunity for the astronomical community and really any interested parties."

    "We're very excited about the citizen science efforts that will be inspired by these images," Guerrero said.
  • A Cosmic Gorilla Effect Could Blind the Detection of Aliens
    Dienstag, 24.04.2018, 01:01:47 Uhr
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    A Cosmic Gorilla Effect Could Blind the Detection of Aliens Madrid, Spain (SPX) Apr 11, 2018 -
    One of the problems that have long intrigued experts in cosmology is how to detect possible extraterrestrial signals. Are we really looking in the right direction? Maybe not, according to the study that the neuropsychologists Gabriel de la Torre and Manuel Garcia, from the University of Cadiz, publish in the journal Acta Astronautica."When we think of other intelligent beings, we tend to see them from our perceptive and conscience sieve; however we are limited by our sui generis vision of the world, and it's hard for us to admit it," says De la Torre, who prefers to avoid the terms 'extraterrestrial' or aliens by its Hollywood connotations and use another more generic, as 'non-terrestrial.'"What we are trying to do with this differentiation is to contemplate other possibilities," he says, "for example, beings of dimensions that our mind cannot grasp; or intelligences based on dark matter or energy forms, which make up almost 95% of the universe and which we are only beginning to glimpse. There is even the possibility that other universes exist, as the texts of Stephen Hawking and other scientists indicate."The authors state that our own neurophysiology, psychology and consciousness can play an important role in the search for non-terrestrial civilizations; an aspect that they consider has been neglected until now.In relation to this, they conducted an experiment with 137 people, who had to distinguish aerial photographs with artificial structures (buildings, roads...) from others with natural elements (mountains, rivers...). In one of the images, a tiny character disguised as a gorilla was inserted to see if the participants noticed.This test was inspired by the one carried out by the researchers Christopher Chabris and Daniel Simons in the 90s to show the inattention blindness of the human being. A boy in a gorilla costume could walk in front of a scene, gesticulating, while the observers were busy in something else (counting the ball passes of players in white shirts), and more than half did not notice."It is very striking, but very significant and representative at the same time, how our brain works," says De la Torre, who explains how the results were similar in the case of his experiment with the images. "In addition, our surprise was greater," he adds, "since before doing the test to see the inattentional blindness we assessed the participants with a series of questions to determine their cognitive style (if they were more intuitive or rational), and it turned out that the intuitive individuals identified the gorilla of our photo more times than those more rational and methodical.""If we transfer this to the problem of searching for other non-terrestrial intelligences, the question arises about whether our current strategy may result in us not perceiving the gorilla," stresses the researcher, who insists: "Our traditional conception of space is limited by our brain, and we may have the signs above and be unable to see them. Maybe we're not looking in the right direction."Another example presented in the article is an apparently geometric structure that can be seen in the images of Occator, a crater of the dwarf planet Ceres famous for its bright spots. "Our structured mind tells us that this structure looks like a triangle with a square inside, something that theoretically is not possible in Ceres," says De la Torre, "but maybe we are seeing things where there are none, what in psychology is called pareidolia."However, the neuropsychologist points out another possibility: "The opposite could also be true. We can have the signal in front of us and not perceive it or be unable to identify it. If this happened, it would be an example of the cosmic gorilla effect. In fact, it could have happened in the past or it could be happening right now."In their study, the authors also pose how different classes of intelligent civilizations could be. They present a classification with three types based on five factors: biology, longevity, psychosocial aspects, technological progress and distribution in space.An example of Type 1 civilizations is ours, which could be ephemeral if it mishandles technology or planetary resources, or if it does not survive a cataclysm. But it could also evolve into a Type 2 civilization, characterized by the long longevity of its members, who control quantum and gravitational energy, manage space-time and are able to explore galaxies."We were well aware that the existing classifications are too simplistic and are generally only based on the energy aspect. The fact that we use radio signals does not necessarily mean that other civilizations also use them, or that the use of energy resources and their dependence are the same as we have," the researchers point out, recalling the theoretical nature of their proposals.The third type of intelligent civilization, the most advanced, would be constituted by exotic beings, with an eternal life, capable of creating in multidimensional and multiverse spaces, and with an absolute dominion of dark energy and matter.Gabriel G. De la Torre and Manuel A. Garcia, "The Cosmic Gorilla Effect or the Problem of Undetected Non Terrestrial Intelligent Signals," Acta Astronautica 146: 83-91, May 2018
  • An amazingly wide variety of disks
    Dienstag, 24.04.2018, 01:01:47 Uhr
    An amazingly wide variety of disks Zurich, Switzerland (SPX) Apr 13, 2018 -
    An instrument, which was partially developed and built at ETH Zurich, has now been particularly successful at studying new born stars still surrounded by gas and dust.With SPHERE (Spectro-Polarimetric High-contrast Exoplanet REsearch) at the European Southern Observatory (ESO), astronomers of ETH Zurich and Max Planck Institute for Astronomy in Heidelberg were able to take images of planet-forming disks around the young stars: these disks, called protoplanetary disks, exist around so-called TTauri stars - the progenitors to our Sun - as well as around the more massive siblings called Herbig Ae/Be stars.So far astronomers focussed mostly on Herbig Ae/Be stars in their studies, but with a new, ambitious program, Henning Avenhaus and Sascha Quanz, former and current members of the NCCR PlanetS at ETH Zurich, have now been able to use the capabilities of SPHERE to undertake a survey of TTauri disks.The results for the first eight stars are released in a paper published by the "Astronomical Journal". "Not only were we able to clearly detect all eight disks," summarizes Henning Avenhaus, "but, surprisingly, they looked all very different in particular with respect to their size."While some of them could only be detected with a radius of 80 au (80 times the distance Sun-Earth and about twice the average distance Sun-Pluto), others could be traced out to an astounding 700 au."Most of the disks were found to display rings, a phenomenon known from previous observations of more massive stars," explains Sascha Quanz: "However, none of them displayed spiral structures, which is a phenomenon seen regularly in Herbig disks." A key question is now to understand where this difference is coming from and what it means for planet formation around different types of stars.Start on a bad footing
    As successful as the project was, it started on a bad footing, as Henning Avenhaus remembers: "While the first proposal to undertake such observations was already written in March 2013 and highly rated (back then using the older NACO instrument), unexpected works that had to be performed on the instrument made it impossible to take data." The same happened again in September 2013. Again, the instrument was not available.A third attempt in March 2014 did yield the requested scheduling - in March 2015, when Henning Avenhaus flew to the telescope just to find out that the instrument (still NACO) had a malfunction the night before the observations were scheduled to start. Not that it mattered: Wind and clouds made it impossible to observe anyway.At this point, the team decided to switch to the new instrument - SPHERE - and got their first observations scheduled in March 2016.This time, it worked: Both the instrument and the weather were well-behaved, as Henning Avenhaus remembers: "I was present at Cerro Paranal, the location of the Very Large Telescope, working through the nights to perform the observations and occasionally peaking out of the control room to head to the telescope platform and marvel at the impressive display of stars."The data taken over the course of several nights in March 2016 and in the following year were of very high quality. More than five years after the idea for the program, the researchers are now rewarded with results that will help to shed more light on the formation processes for planets."This high-quality dataset impressively shows the power of SPHERE for these observations and significantly increases the number of planetary nurseries studied at high resolution enabling us to eventually get a statistical grasp on planet formation," summarizes Sascha Quanz. Further results of the DARTTS-S programme and similar observations with the ALMA radio telescope in Chile should contribute to this.
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