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  • richardmitnick 2:40 pm on June 7, 2018 Permalink | Reply
    Tags: Astrobiology, , , , ,   

    From Many Worlds: “Breakthrough Findings on Mars Organics and Mars Methane” 

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    NASA NExSS

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    From Many Worlds

    2018-06-07
    Marc Kaufman

    NASA Mars Curiosity Rover

    After almost six years of searching, drilling and analyzing on Mars, the Curiosity rover team has conclusively detected three types of naturally-occurring organics that had not been identified before on the planet.

    The Mars organics Science paper by NASA’s Jennifer Eigenbrode and much of the rover’s Sample Analysis on Mars (SAM) instrument team was twinned with another paper describing the discovery of a seasonal pattern to the release of the simple organic gas methane on Mars.

    This finding is also a major step forward not only because it provides ground truth for the difficult question of whether significant amounts of methane are in the Martian atmosphere, but equally important it determines that methane concentrations appear to change with the seasons. The implications of that seasonality are intriguing, to say the least.

    In an accompanying opinion piece in Science, Inges Loes ten Kate of Utrecht University in Netherlands wrote of the two papers: “Both these findings are breakthroughs in astrobiology.”

    2
    Remains of 3.5 billion-year old lake that once filled Gale Crater. NASA scientists concluded early in the Curiosity mission that the planet was habitable long ago based on the study of mudstone remains like these. (NASA/JPL-Caltech/MSSS).

    Finding organic compounds on Mars has been a prime goal of the Curiosity rover mission.

    Those carbon-based compounds surely fall from the sky on Mars, as they do on Earth and everywhere else, but identifying them has proven illusive.

    The consequences of that non-discovery have been significant. Going back to the Viking missions of 1976, scientists concluded that life was not possible on Mars because there were no organics, or none that were detected.

    But the reasons for the disappearing organics are pretty well understood. Without much of an atmosphere to protect it, the Martian surface is bombarded with ultraviolet radiation, which can destroy organic compounds. Or, in the case of the samples discovered by the SAM team, large organic macromolecules — the likes of proteins, membranes and DNA — are broken up into much smaller pieces.

    That’s what the team found, Eigenbrode told me. The organics were probably preserved, she said, because of exceptionally high levels of sulfur present in that part of Gale Crater.

    The organics, extracted from mudstone at the Mojave and Confidence Hill sites, had bonded tightly with ancient non-organic material. The organic material was freed to be collected as gas only after being exposed to temperatures of more than 500 to 800 centigrade in the SAM oven.

    “This material was buried for billions of years and then exposed to extreme surface conditions, so there’s a limit to what we can learn about. Did it come from life? We don’t know.

    “But the fact we found the organic carbon adds to the habitability equation. It was in a lake environment that we know could have supported life. Organics are things that organisms can eat.”

    It will take different kinds of instruments and samples from drilling deeper into the extreme Martian surface to answer the question of whether the organics came from living microbes. But for Eigenbrode, future answers of either “yes” or “no” are almost equally interesting.

    Finding clear signs of early Martian life would certainly be hugely important, she said. But a conclusion that Mars never had life — although it had conditions some 3.5 to 3.8 billion years ago quite similar to conditions on Earth at that time — raises the obvious question of “why not?”

    3
    NASA’s Curiosity rover raised robotic arm with drill pointed skyward while exploring Vera Rubin Ridge at the base of Mount Sharp inside Gale Crater. This navcam camera mosaic was stitched from raw images taken on Sol 1833, Oct. 2, 2017 and colorized. (NASA/JPL-Caltech/Ken Kremer, Marco Di Lorenzo)

    Organic molecules are the building blocks of all known life on Earth, and consist of a wide variety of molecules made primarily of carbon, hydrogen, and oxygen atoms. However, organic molecules can also be made by chemical reactions that don’t involve life.

    Examples of non-biological sources include chemical reactions in water at ancient Martian hot springs or delivery of organic material to Mars by interplanetary dust or fragments of asteroids and comets.

    It needs to be said that today’s Mars organics announcement was not the first we have heard. In 2014, a NASA team reported the presence of chlorine-based organics in Sheepbed mudstone at Yellowknife Bay, the first ancient Mars lake visited by Curiosity.

    That work, led by NASA Goddard scientists Caroline Freissinet and Daniel Glavin and published in the Journal of Geophysical Research, focused on signatures from unusual organics not seen naturally on Earth.

    The organics were complex and made entirely of Martian components, the paper reported. But because they combined chlorine with the organic hydrocarbons, they are not considered to be as “natural” as the discovery announced today.

    And when it comes to organics on Mars, the complicated history of research into the presence of the gas methane (a simple molecule that consists of carbon and hydrogen) also shows the great challenges involved in making these measurements on Mars.

    4
    By measuring absorption of light at specific wavelengths, the tunable laser spectrometer on Curiosity measures concentrations of methane, carbon dioxide and water vapor in the Martian atmosphere. (NASA)

    4
    The gold-plated Sample Analysis on Mars contains three instruments that make the measurements of organics and methane. (NASA/Goddard Space Flight Center)

    The second Science paper, authored by Chris Webster of NASA’s Jet Propulsion Lab and colleagues, reports that the gas methane has been detected regularly in recent years, with surprising seasonality.

    “The history of Mars methane has been frustrating, with reports of some large plumes and spikes detected, but none have been repeatable. It’s almost like they’re random,” he told me. “But now we can see a large seasonal cycle in the background of these detections, and that’s extremely important.”

    Over three Mars years, or almost five Earth years, Webster said there have been significant increases in methane detected during the summer, and especially the late summer. That tripling of the methane counts is considered too great to be random, especially since the count declines as predicted after the summer ends.

    No definite explanation of why this happens has emerged yet, but one theory has been embraced by some scientists.

    While it is still cold in the Martian summer, it can get warm enough where the sun shines directly on a collection of ice for some melting to occur. And that melting, the paper reports, could provide an escape valve for methane collected long ago under the surface. The process is termed “microseepage.”

    5
    This illustration shows the ways in which methane from the subsurface might find its way to the
    surface where its release could produce the large seasonal variation in the atmosphere
    as observed by Curiosity. Potential methane sources include byproducts from organisms alive or long dead, ultraviolet degradation of organics, or water-rock chemistry; and its losses include atmospheric photochemistry and surface reactions. Seasons refer to the northern hemisphere. The plotted data is from Curiosity’s TLS-SAM instrument, and the curved line through the data is to aid the eye. (NASA/JPL-Caltech)

    Methane is a crucial organic in astrobiology because most of that gas found on Earth comes from biology, although various non-biological processes can produce methane as well.

    Today’s paper by Webster et al is the third in Science on Mars methane as measured by Curiosity, and it is the first to find a seasonal pattern. The first paper, in 2013 Science, actually reported there was no methane measured in early runs, a conclusion that led to push-back from many of those working in the field.

    While the Mars methane results released today are being described as a “breakthrough,” they follow closely the findings of a Science paper in 2009 by Michael Mumma and Geronimo Villanueva, both at NASA Goddard.

    The two reported then similar findings of plumes of methane on Mars, of a seasonality associated with their distribution, and a similar conclusion that the methane probably was coming from subsurface reservoirs. Like Webster et al, Mumma and Villanueva said they were unable to determine if the source of methane was biological or geological.

    The methane levels in the plumes they found were considerably higher than detected so far by Curiosity, but what they were detecting was quite different. Using ground-based telescopes, they detected the high concentrations in two specific areas over a number of years, while Curiosity is measuring methane levels that are more global or regional.

    Just as Webster was criticized for his initial paper saying there was no methane detected on Mars, the Mumma team also got sharp questions about their methodology and conclusions. This grew as their numerous follow-up efforts to detect the Mars methane proved unsuccessful.

    But now Webster says the Curiosity findings have essentially “confirmed” what Mumma and Villanueva reported nine years ago.

    Still, the Curiosity results are a breakthrough because they were made on Mars rather than through a telescope. Mumma, who described the new Curiosity results as “satisfying,” agreed that they were a major step forward.

    “This is how science works,” he said. “We do our work and put out our papers and other scientists react. We take it all in and make changes if needed. But the big changes come when new, and maybe different, data is presented.”

    And that’s exactly what will be happening soon regarding methane on Mars. Beginning early this year, the European/Russian Trace Gas Orbiter (TGO) has been collecting data specifically on Mars gases including methane. Unlike previous Mars methane campaigns, this one can potentially determine whether the methane being released from below the surface was formed by biology or geology — although not without great difficulty.

    Mumma, who is part of that TGO team, said the first release of information is due in the fall.

    See the full article here .


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    About Many Worlds

    There are many worlds out there waiting to fire your imagination.

    Marc Kaufman is an experienced journalist, having spent three decades at The Washington Post and The Philadelphia Inquirer, and is the author of two books on searching for life and planetary habitability. While the “Many Worlds” column is supported by the Lunar Planetary Institute/USRA and informed by NASA’s NExSS initiative, any opinions expressed are the author’s alone.

    This site is for everyone interested in the burgeoning field of exoplanet detection and research, from the general public to scientists in the field. It will present columns, news stories and in-depth features, as well as the work of guest writers.

    About NExSS

    The Nexus for Exoplanet System Science (NExSS) is a NASA research coordination network dedicated to the study of planetary habitability. The goals of NExSS are to investigate the diversity of exoplanets and to learn how their history, geology, and climate interact to create the conditions for life. NExSS investigators also strive to put planets into an architectural context — as solar systems built over the eons through dynamical processes and sculpted by stars. Based on our understanding of our own solar system and habitable planet Earth, researchers in the network aim to identify where habitable niches are most likely to occur, which planets are most likely to be habitable. Leveraging current NASA investments in research and missions, NExSS will accelerate the discovery and characterization of other potentially life-bearing worlds in the galaxy, using a systems science approach.
    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

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    • stewarthoughblog 12:28 am on June 8, 2018 Permalink | Reply

      Fascinating results and science from exploration and experiments on Mars. Understanding that much of the funding justification is predicated on the possibility of hopefully finding evidence of life, past or present, the whole thing is seriously over-optimistic and not scientifically based on reality. Proposing Mars was once habitable to a level similar on Earth is extremely speculative, especially considering that primordial Earth conditions are not comprehensively understood. More importantly, there are no naturalistic processes capable of creating life, no matter the planet examined. Consequently, the only life found on Mars will be Earth effluent.

      Like

  • richardmitnick 5:31 pm on June 5, 2018 Permalink | Reply
    Tags: , Astrobiology, , , ENIGMA-Evolution of Nanomachines in Geospheres and Microbial Ancestors, ,   

    From Rutgers: “NASA Funds Rutgers Scientists’ Pursuit of the Origins of Life” 

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    Our Great Seal.

    From Rutgers University

    [THIS POST IS DEDICATED TO L.Z. OF RUTGERS AND HP FOR HIS UNENDING SUPPORT OF THIS BLOG AND PHYSICS AT RUTGERS UNIVERSITY]

    Jun 4, 2018

    Todd Bates
    848-932-0550
    todd.bates@rutgers.edu

    Rutgers-led ENIGMA team examines whether “protein nanomachines” in our cells arose before life on Earth, other planets.

    What are the origins of life on Earth and possibly elsewhere? Did “protein nanomachines” evolve here before life began to catalyze and support the development of living things? Could the same thing have happened on Mars, the moons of Jupiter and Neptune, and elsewhere in the universe?

    A Rutgers University-led team of scientists called ENIGMA, for “Evolution of Nanomachines in Geospheres and Microbial Ancestors,” will try to answer those questions over the next five years, thanks to an approximately $6 million NASA grant and membership in the NASA Astrobiology Institute.

    Rutgers Today asked Paul G. Falkowski, ENIGMA principal investigator and a distinguished professor at Rutgers University–New Brunswick, about research on the origins of life.

    1
    Iron- and sulfur-containing minerals found on the early Earth (greigite, left, is one example) share a remarkably similar molecular structure with metals found in modern proteins (ferredoxin, right, is one example). Did the first proteins at the dawn of life on Earth interact directly with rocks to promote catalysis of life?
    Image: Professor Vikas Nanda/Center for Advanced Biotechnology and Medicine at Rutgers

    What is astrobiology?

    It is the study of the origins of life on Earth and potential life on planets – called extrasolar planets – and planetary bodies like moons in our solar system and other solar systems. More than 3,700 extrasolar planets have been confirmed in the last decade or so. Many of these are potentially rocky planets that are close enough to their star that they may have liquid water, and we want to try and understand if the gases on those planets are created by life, such as the oxygen on Earth.

    What is the ENIGMA project?

    All life on Earth depends on the movement of electrons; life literally is electric. We breathe in oxygen and breathe out water vapor and carbon dioxide, and in that process we transfer hydrogen atoms, which contain a proton and an electron, to oxygen to make water (H20). We move electrons from the food we eat to the oxygen in the air to derive energy. Every organism on Earth moves electrons to generate energy. ENIGMA is a team of primarily Rutgers researchers that is trying to understand the earliest evolution of these processes, and we think that hydrogen was probably one of the most abundant gases in the early Earth that supported life.

    What are the chances of life being found elsewhere in our solar system and the universe?

    We’ve been looking for evidence of life on Mars since the Viking mission, which landed in 1976. I think it will be very difficult to prove there is life on Mars today, but there may be signatures of life that existed on Mars in the distant past. Mars certainly had a lot of water on it and had an atmosphere, but that’s all largely gone now. A proposed mission to Europa – an ice-covered moon of Jupiter – is in the planning phase. NASA’s Cassini mission to investigate Titan, a moon of Neptune, revealed liquid methane over what we think is water – very cold, shallow oceans – so there may be life on Titan.

    What are protein nanomachines?

    They are enzymes that physically move. Each time we take a breath, an enzyme in every cell allows you to transfer electrons to oxygen. Enzymes, like all proteins, are made up of amino acids, of which there are 20 that are used in life. Early on, amino acids were delivered to Earth by meteorites, and we think some of these amino acids could have been coupled together and made nanomachines before life began. That’s what we’re looking to see if we can recreate, using the tens of thousands of protein structures in the Protein Data Bank at Rutgers together with our colleagues in the Center for Advanced Biotechnology and Medicine.

    What are the next steps?

    Organizing our research so it is coherent and relevant to the other collaborating teams in the NASA Astrobiology Institute. We want to develop an education and outreach program at Rutgers that leads to an astrobiology minor for undergraduate students and helps inform K-12 schoolchildren about the origins of life on Earth and what we know and don’t know about the potential for life on other planets. We also want to help make Rutgers a center of excellence in this field so future undergraduate and graduate students and faculty will gravitate towards this university to try to understand the evolution and origin of the molecules that derive energy for life.

    See the full article here .

    Follow Rutgers Research here .

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    Rutgers, The State University of New Jersey, is a leading national research university and the state’s preeminent, comprehensive public institution of higher education. Rutgers is dedicated to teaching that meets the highest standards of excellence; to conducting research that breaks new ground; and to providing services, solutions, and clinical care that help individuals and the local, national, and global communities where they live.

    Founded in 1766, Rutgers teaches across the full educational spectrum: preschool to precollege; undergraduate to graduate; postdoctoral fellowships to residencies; and continuing education for professional and personal advancement.

    As a ’67 graduate of University college, second in my class, I am proud to be a member of

    Alpha Sigma Lamda, National Honor Society of non-tradional students.

     
    • stewarthoughblog 1:20 am on June 6, 2018 Permalink | Reply

      I suppose it is inevitable for naturalists to revisit the myths of chemical evolution, Darwin’s “warm little ponds,” OparinHaldane prebiotic soup, Miller-Urey test tube goo, FeS minerals, etc. This may get funding, have some interesting science, but otherwise will offer nothing to the present chaotic mess of naturalist origin of life, OoL, research.
      If they really want to address OoL, then they need to explain the creation of DNA and the homochiral amino acids and pentose sugars required. The 20 amino acids mentioned are exclusively produced through cellular, aka living, functions, never naturalistically. There is no naturalistic process capable of producing all amino acids.
      The propositions in this article are intellectually insulting and scientifically nonsensical.

      Like

      • richardmitnick 12:59 pm on June 6, 2018 Permalink | Reply

        While I respect your opinions, the main reason I posted this was that anything good that happens at Rutgers, my alma mater, I need to jump on. Rutgers is a great research university with a penchant for very poor representation in social media.

        Like

        • stewarthoughblog 11:32 pm on June 6, 2018 Permalink

          Richard, no slight intended against your alma mater, but it is the substance of the article that prompted my comment, which I can only propose was written by someone very uninformed about the pertinent science, or by a fully impregnated naturalistic ideologue, if you know what I mean.. Regards.

          Like

        • richardmitnick 3:13 pm on June 7, 2018 Permalink

          No harm, no foul. I appreciate your continued interest in the blog. I am in a personal war with Rutgers to wake them up to their web compeition like all of the University of California schools, UBC, U Toronto, U Arizona, a bunch of “state” schools in Australia, and the like, all state schools. I am not asking them to to be Harvard, MIT, Caltech, Oxford or Cambridge. I want what I want.

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  • richardmitnick 11:45 am on May 30, 2018 Permalink | Reply
    Tags: Astrobiology, Existence of a thick haze around the early Archean Earth and probably today around some and perhaps many exoplanets, Exoplanet biosignatures, , NASA Goddard Space Flight Center astronomer and astrobiologist Giada Arney, Niki Parenteau of NASA’s Ames Research Center, Radiation-under what conditions the organisms can survive, So how did organisms survive the radiation assault?, The microbes-and-haze experiment is one of many that Parenteau is working on in the general field of biosignatures, The search for extraterrestrial life, This can all tested in a lab   

    From Many Worlds: “Joining the Microscope and the Telescope in the Search for Life Beyond Earth” 

    NASA NExSS bloc

    NASA NExSS

    Many Words icon

    2018-05-30
    Marc Kaufman

    1
    Niki Parenteau of NASA’s Ames Research Center is a microbiologist working in the field of exoplanet and Mars biosignatures. She adds a laboratory biology approach to a field generally known for its astronomers, astrophysicists and planetary scientists. (Marisa Mayer, Stanford University.)

    The world of biology is filled with labs where living creatures are cultured and studied, where the dynamics of life are explored and analyzed to learn about behavior, reproduction, structure, growth and so much more.

    In the field of astrobiology, however, you don’t see much lab biology — especially when it comes to the search for life beyond Earth. The field is now largely focused on understanding the conditions under which life could exist elsewhere, modeling what chemicals would be present in the atmosphere of an exoplanet with life, or how life might begin as an organized organism from a theoretical perspective.

    Yes, astrobiology includes and learns from the study of extreme forms of life on Earth, from evolutionary biology, from the research into the origins of life.

    But the actual bread and butter of biologists — working with lifeforms in a lab or in the environment — plays a back seat to modeling and simulations that rely on computers rather than actual life.

    There are certainly exceptions, and one of the most interesting is the work of Mary “Niki” Parenteau at NASA’s Ames Research Center in the San Francisco Bay area.

    2
    Niki Parenteau with her custom-designed LED array, can reproduce the spectral features of different simulated stellar and atmospheric conditions to test on primitive microbes. (Marc Kaufman)

    A microbiologist by training, she has been active for over five years now in the field of exoplanet biosignatures — trying to determine what astronomers could and should look for in the search for extraterrestrial life.

    Working in her lab with actual live bacteria in laboratory flasks, test tubes and tanks, she is conducting traditional biological experiments that have everything to do with astrobiology.

    She takes primitive bacteria known to have existed in some form on the early Earth, and she blasts them with the radiation that would have hit the planet at the time to see under what conditions the organisms can survive. She has designed ingenious experiments using different forms of ultraviolet light and a LED array that simulate the broad range of radiations that would come from different types of stars as well.

    What makes this all so intriguing is that her work uses, and then moves forward, cutting edge modeling from astronomers and astrobiologists regarding thick photochemical hazes understood to have engulfed the early Earth — making the planet significantly colder but also possibly providing some protection from deadly ultraviolet radiation.

    That was a time when the atmosphere held very little oxygen, and when many organisms had to make their living via carbon dioxide and sulfur-based photosynthesis that did not use water and did not produce oxygen. This kind of photosynthesis has been the norm for much of the history of life on Earth, and certainly could be common on many exoplanets orbiting other stars as well.

    So anything learned about how these early organisms survived in frigid conditions with high ultraviolet radiation — and what potentially detectable byproducts they would have produced under those conditions — would be important in the search for biosignatures and extraterrestrial life.

    Parenteau has spent years learning from astronomers working to find ways to characterize exoplanet biosignatures, and she has been eager to convert her own work into something useful to them.

    “These are not questions that can be answered by one discipline,” she told me. “I certainly understand that when it comes to exoplanet biosignatures and life detection, astronomy has to be in the lead. But biologists have a role to play, especially when it comes to characterizing what life produces.”

    Here is the back story to Parenteau’s work:

    Recent work by NASA Goddard Space Flight Center astronomer and astrobiologist Giada Arney and colleagues points to the existence of a thick haze around the early Archean Earth and probably today around some, and perhaps many, exoplanets.

    3
    Giada Arney is an astronomer and astrobiologist at NASA’s Goddard Space Flight Center. As with Parenteau, her general approach to science was formed at the University of Washington’s pioneering Virtual Planetary Laboratory. (NASA/Goddard Space Flight Center)

    This haze — which is more like pollution than clouds — is produced by the interaction of strong incoming radiation and chemicals (most commonly methane and carbon dioxide) already in the atmosphere.

    The haze, Arney concluded based on elaborate modeling of those radiation-chemical interactions, would be hard on any life that might exist on the planet because it would reduce surface temperatures significantly, though probably not always fatally.

    On the other hand, the haze would also have the effect of blocking 84 percent of the destructive ultraviolet radiation bombarding the planet — especially the most damaging ultraviolet-C light that would otherwise destroy nucleic acids in cells and disrupt the working of DNA. (Ultraviolet-C radiation is used as a microbial disinfectant.)

    Ozone in our atmosphere now plays the role of blocking the most destructive forms of UV radiation, but ozone is formed from oxygen and on early Earth there was very little oxygen at all.

    So how did organisms survive the radiation assault? Might it have been that haze? And might there be hazes surrounding exoplanets as well? (None have been found so far.)

    It’s difficult enough to sort through the potentially protective role of a haze on early Earth. To do it for exoplanets requires not only an understanding of the effects of a haze on ultraviolet light, but also how the dynamics of a haze would change based on the amounts and forms of radiation emitted by different types of stars.

    It’s all very complicated, but the answers needn’t be theoretical, Arney concluded. They could be tested in a lab.

    And that’s where Parenteau comes in, with her desire and ability to design biological experiments that might help scientists understand better how to look for life on distant exoplanets.

    “I knew that (Parenteau) had been super interested in this kind of question for a long time,” Arney said. “She one of the few people in the world with the know-how to simulate an atmosphere, and probably the only one in the world who could do the experiment.”

    4
    The 48 LEDs (light-emitting diodes) of the board designed and created by Parenteau and Ames intern Cameron Hearne. Each one is independently controlled and can be used to simulate the amount of radiation arriving on a planetary surface — taking into account the flux from the planet’s star and some aspects of its atmosphere. A microbe is then exposed to the radiation to see whether or how it can survive. (Niki Parenteau.)

    Parenteau’s experiment at first looks pretty low-tech, but in fact it’s very much custom-designed and custom-built.

    The ultraviolet bulbs include the powerful, germicidal ultraviolet-C variety, some of the glass for the experiment is made of special quartz that is transparent to that ultraviolet light, the LED array has 48 tiny bulbs that can be controlled by software to provide different amounts and kinds of light as identified and provided by Arney

    Before designing and making her own LED board with Ames intern Cameron Hearne, Parenteau met with solar panel specialists who might be able to provide an instrument she could use, but it turned out they were very expensive and not nearly as versatile as she wanted. Having grown up on a farm in northern Idaho, Parenteau is comfortable with making things from scratch, and her experiments reflect that comfort and talent.

    How would Parenteau determine whether the haze does indeed protect the microbial cells after exposing them to the various radiation regimes? This is how she explained the process, which measures the number of cells living or dead given a simulated UV and stellar bombardment:

    “Imagine the cells as soap bubbles in a clear glass. If you look through the glass, the soap bubbles prevent you from seeing through and the glass has a higher ‘optical density.’ However, if you pop or lyse the soap bubbles, suddenly you can see through the glass and the optical density decreases.

    “The latter represents dead ‘popped’ cells that were killed by the UV irradiation. I predict that by simulating the spectral qualities of the haze, which decreases the UV flux by 84%, more cells will survive.”

    The Parenteau-Arney collaboration is being funded through a National Astrobiology Institute grant to the University of Washington’s famously-interdisciplinary Virtual Planetary Laboratory.

    The microbes-and-haze experiment is one of many that Parenteau is working on in the general field of biosignatures. While the haze experiment is primarily designed to determine if microbes could survive a UV bombardment if a haze was present, she is also working on the central question of what might constitute a biosignature.

    With that in mind, she is also measuring the gases produced by microbes under different radiation and atmospheric conditions, and that is directly applicable to searching for extraterrestrial life.

    5
    A densely-packed community of microbes, including oxygen-producing cyanobacteria as well as anoxygenic purple and green bacteria, being studied with Parenteau’s LED array. A central question involves what gases are emitted and might be detectable on a distant planet. (Niki Parenteau)

    6
    Parenteau’s lab glove box with green, purple and other bacteria that is regularly exposed to radiation conditions believed to have existed on early Earth when a photochemical haze is believed to have been present. (Marc Kaufman)

    If and when she does find particularly interesting results in the gas measurements inside the anaerobic glove box, she says, she knows where to go.

    “I would hand the results to an astronomer. We could say that if a particular kind of exoplanet with a particular atmosphere had microbial life, this is the suite of gases we would expect to be emitted.”

    Those gases, Parenteau says, may be photochemically altered as they as they rise through the planet’s atmosphere to the upper levels where they could be detected by the telescopes of the future. But in the challenging and complex world of biosignatures, every bit of hard-won data is most valuable since it could some day lead to a discovery for the ages.

    See the full article here .


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    About Many Worlds

    There are many worlds out there waiting to fire your imagination.

    Marc Kaufman is an experienced journalist, having spent three decades at The Washington Post and The Philadelphia Inquirer, and is the author of two books on searching for life and planetary habitability. While the “Many Worlds” column is supported by the Lunar Planetary Institute/USRA and informed by NASA’s NExSS initiative, any opinions expressed are the author’s alone.

    This site is for everyone interested in the burgeoning field of exoplanet detection and research, from the general public to scientists in the field. It will present columns, news stories and in-depth features, as well as the work of guest writers.

    About NExSS

    The Nexus for Exoplanet System Science (NExSS) is a NASA research coordination network dedicated to the study of planetary habitability. The goals of NExSS are to investigate the diversity of exoplanets and to learn how their history, geology, and climate interact to create the conditions for life. NExSS investigators also strive to put planets into an architectural context — as solar systems built over the eons through dynamical processes and sculpted by stars. Based on our understanding of our own solar system and habitable planet Earth, researchers in the network aim to identify where habitable niches are most likely to occur, which planets are most likely to be habitable. Leveraging current NASA investments in research and missions, NExSS will accelerate the discovery and characterization of other potentially life-bearing worlds in the galaxy, using a systems science approach.
    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

     
  • richardmitnick 11:41 am on May 11, 2018 Permalink | Reply
    Tags: Astrobiology, , , , , First Mapping of Interstellar Clouds in Three Dimensions- a Key Breakthrough for Better Understanding Star Formation,   

    From Many Worlds: “First Mapping of Interstellar Clouds in Three Dimensions; a Key Breakthrough for Better Understanding Star Formation” 

    NASA NExSS bloc

    NASA NExSS

    Many Words icon

    From Many Worlds

    2018-05-11
    Marc Kaufman

    1
    This snakelike gas cloud (center dark area) in the constellation Musca resembles a skinny filament. But it’s actually a flat sheet that extends about 20 light-years into space away from Earth, an analysis finds. (Dylan O’Donnell, deography.com/WikiCommons)

    When thinking and talking about “astrobiology,” many people are inclined to think of alien creatures that often look rather like us, but with some kind of switcheroo. Life, in this view, means something rather like us that just happens to live on another planet and perhaps uses different techniques to stay alive.

    But as defined by NASA, and what “astrobiology” is in real scientific terms, is the search for life beyond Earth and the exploration of how life began here. They may seem like very different subjects but are actually joined at the hip; having a deeper understanding of how life originated on Earth is surely one of the most important set of clues to how to find it elsewhere.

    Those con-joined scientific disciplines — the search for extraterrestrial life and the extraordinarily difficult task of analyzing how it started here — together raise another most complex challenge.

    Precisely how far back do we look when trying to understand the origins of life? Do we look to Darwin’s “warm little pond?” To the Miller-Urey experiment’s conclusion that organic building blocks of life can be formed by sparking some common gases and water with electricity? To an understanding the nature and evolution of our atmosphere?

    The answer is “yes” to all, as well as to scores of additional essential dynamics of our galaxies. Because to begin to answer those three questions, we also have to know how planets form, the chemical make-up of the cosmos, how different suns effect different exoplanets and so much more.

    This is why I was so interested in reading about a breakthrough approach to understanding the shape and nature of interstellar clouds. Because it is when those clouds of gas and dust collapse under their own gravitational attraction that stars are formed — and, of course, none of the above questions have meaning without preexisting stars.

    In theory, the scope of astrobiology could go back further than star-formation, but I take my lead from Mary Voytek, chief scientist for astrobiology at NASA. The logic of star formation is part of astrobiology, she says, but the innumerable cosmological developments going back to the Big Bang are not.

    So by understanding something new about interstellar clouds — in this case determining the 3D structure of such a “cloud” — we are learning about some of the very earliest questions of astrobiology, the process that led over the eons to us and most likely life of some sort on the billions of exoplanets we now know are out there.

    2
    Cepheus B, a molecular cloud located in our Milky Galaxy about 2,400 light years from the Earth, provides an excellent model to determine how stars are formed. This composite image of Cepheus B combines data from the Chandra X-ray Observatory and the Spitzer Space Telescope.The Chandra observations allowed the astronomers to pick out young stars within and near Cepheus B, identified by their strong X-ray emission.
    Credits X-ray: NASA/CXC/PSU/K. Getman et al.; IRL NASA/JPL-Caltech/CfA/J. Wang et al.

    NASA/Chandra X-ray Telescope

    NASA/Spitzer Infrared Telescope

    So, what is an interstellar cloud?

    It’s the generic name given to an accumulation of gas, plasma, and dust in our and other galaxies, left over from galaxy formation. So an interstellar cloud is a denser-than-average region of the interstellar medium.

    Hydrogen is its primary component, and that hydrogen exists in a wide variety of states depending on the density, the age, the location and more of the cloud.

    Until recently the rates of reactions in interstellar clouds were expected to be very slow, with minimal products being produced due to the low temperature and density of the clouds. However, organic molecules were observed in the spectra that scientists would not have expected to find under these conditions, such as formaldehyde, methanol, and vinyl alcohol.

    The reactions needed to create such substances are familiar to scientists only at the much higher temperatures and pressures of earth and earth-based laboratories. The fact that they were found indicates that these chemical reactions in interstellar clouds take place faster than suspected, likely in gas-phase reactions unfamiliar to organic chemistry as observed on earth.

    What was newly revealed this week is that it is possible to determine the 3D structure of an interstellar cloud. The advance not only reveals the true structure of the molecular cloud Musca, which differs from previous assumptions in looking more like a pancake than a needle.

    But the two authors, astrophysicist Konstantinos Tassis of the University of Crete and Aris Tritsis, now a postdoctoral fellow at Australian National University, say their discovery will lead to a better understanding of the evolution of interstellar clouds in general. This, in turn, which will help astronomers answer the longstanding questions of how and why the enormous number and wild variety of stars exists in our galaxy and beyond.

    The two put together a video to help explain the science of Musca and its dimensions. The work was published in the journal Science, and here is their description of what the video shows:

    “The first part of the movie gives an overview of the problem of viewing star-forming clouds in 2D projection. The second part of the video shows the striations in Musca, and the process through which the normal mode spatial frequencies are recovered. The third part of the movie demonstrates how the apparently complex profiles of the intensity cuts through striations are reproduced by progressively summing the theoretically predicted normal modes. At this part of the video (1:30-1:52) the spatial frequencies are scaled to the frequency range of human hearing and are represented by the musical crescendo.”

    In an email, Tritsis said that this is the first time that the 3-dimensional coordinates of an interstellar cloud have been measured.

    “There have been other crude estimates of the 3D sizes of clouds that relied on many assumptions so this is the first time we were able to determine the size with such accuracy and certainty,” he wrote.

    “What we are after is the physics that controls the nature of the stars that will form. This physics will dictate how many star will form and with what masses, but it will also be responsible for shaping the cloud. Thus, this physics is encoded in the shape and that is why we are so interested about it.”

    Their pathway in to mapping a 3D cloud was the striations (wispy stripe-like patterns) they detected within the cloud. They show that these striations form by the excitation of fast magnetosonic waves (longitudinal magnetic pressure waves) – the cloud is vibrating, like a bell ringing after it has been struck.

    “What we have actually found is that the entire cloud oscillates just like waves on the surface of a pond,” he wrote in his email.

    “However, in this instance is not the surface of the water that is oscillating but the magnetic field that is threading the cloud. Furthermore, because these waves get trapped, they act like a fingerprint. They are unique and by studying their frequencies we can deduce the sizes of the boundaries that confined them.

    “It is the same concept as a violin and a cello making very different sounds. In a similar fashion, clouds with different shapes and sizes will vibrate differently. After having identify the frequencies of these oscillations we scaled them to the frequency range of human hearing to get the ‘song of Musca’!”

    By analyzing the frequencies of these waves the authors produce a model of the cloud, showing that Musca is not a long, thin filament as once thought, but rather a vast sheet-like or pancake structure that stretches 20 light-years away from Earth. (The cloud is some 27 light 490 and 650 light-years from Earth.)

    With the determination of its 3D nature, the scientists modeled a cloud that is ten times more spacious than earlier thought.

    From the 3D reconstruction, the authors were able to determine the cloud’s density. Tritsis and Tassis note that, with its geometry now determined, Musca can be used to test theoretical models of interstellar clouds.

    “Because of the fact that Musca is isolated and it is very ordered, it was the obvious choice for us to test our method,” Tritis wrote. “However, other clouds out there could also vibrate globally.

    “Knowing the exact dimensions of Musca, we can simulate it in great detail, calculate many different properties of this particular cloud based on different star formation models, and compare them with observations.

    “We believe that, with its 3D structure revealed, Musca will now act as a prototype laboratory to study star formation in greater detail than ever before. The Musca star formation saga is only now beginning, and this is a very exciting development that goes beyond this particular discovery.”

    And in that way, the discovery is very much a part of the long and broad sweep of astrobiology.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    About Many Worlds

    There are many worlds out there waiting to fire your imagination.

    Marc Kaufman is an experienced journalist, having spent three decades at The Washington Post and The Philadelphia Inquirer, and is the author of two books on searching for life and planetary habitability. While the “Many Worlds” column is supported by the Lunar Planetary Institute/USRA and informed by NASA’s NExSS initiative, any opinions expressed are the author’s alone.

    This site is for everyone interested in the burgeoning field of exoplanet detection and research, from the general public to scientists in the field. It will present columns, news stories and in-depth features, as well as the work of guest writers.

    About NExSS

    The Nexus for Exoplanet System Science (NExSS) is a NASA research coordination network dedicated to the study of planetary habitability. The goals of NExSS are to investigate the diversity of exoplanets and to learn how their history, geology, and climate interact to create the conditions for life. NExSS investigators also strive to put planets into an architectural context — as solar systems built over the eons through dynamical processes and sculpted by stars. Based on our understanding of our own solar system and habitable planet Earth, researchers in the network aim to identify where habitable niches are most likely to occur, which planets are most likely to be habitable. Leveraging current NASA investments in research and missions, NExSS will accelerate the discovery and characterization of other potentially life-bearing worlds in the galaxy, using a systems science approach.
    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

     
  • richardmitnick 3:25 pm on March 16, 2018 Permalink | Reply
    Tags: Astrobiology, , , , , Language arts, , , Speak like a human to ET   

    From METI: “Speak like a human to ET” 

    1

    METI (Messaging Extraterrestrial Intelligence) International has announced plans to start sending signals into space

    METI International

    3.16.18

    Morris Jones

    Much attention in the METI world is focused on designing codes or languages that could be understood by extraterrestrials. We don’t think they would speak any languages commonly used by humans, so attempts are made to produce something close to a “universal language”. Mathematics heavily influences this process, and with good reason. It’s a more objective reflection of the universe, and taps into rules and laws that would apply to extraterrestrials as much as us. Addition works the same way on Earth and Proxima Centauri. But even the way humans interpret and communicate mathematics is subjective. It’s not only the code and symbolism we use. It could even reflect cognitive processes that could be unique to humans, and not necessarily shared by creatures with different minds.

    Other attempts at communication involve photographs and pictograms. But even these efforts can be less clear than we think. What we show, and what we expect to be interpreted, can be very different. People read different messages into the same image, even if they speak the same language. These differences can be profound between members of the same species. Imagine how this would affect communication between different planets!

    This analyst thus seeks to highlight a paradigm that approaches extraterrestrial messaging from another angle. Speak like a human! We don’t know how extraterrestrials think or communicate. Any effort we make in this regard is likely to have problems. But we know how humans communicate very well. Our languages and media (including all the arts) are vivid and profound. We have a lot to say, and the means to do so. Our systems are not always perfect, but they are effective.

    SETI and METI scientists love to invoke analogy in their considerations of extraterrestrials. We know about humans but we know essentially nothing about extraterrestrials. So it makes sense to work with what you have. Extrapolating human factors to extraterrestrials is hazardous, but it does have some degree of utility. There is likely to be a lot in common, even though there could be profound differences.

    Let’s apply this principle to communication. The languages of humans are known to us. They could even be more universal than we realize. Cognitive scientists and linguists claim that much of the basis of language seems to be hardwired into our brains, whether we speak Spanish or Swahili. There could even be principles of logic and information theory that mandate certain factors in communication, regardless of biology. Extraterrestrials may not think exactly the same way or communicate as we do, but they could still decipher much of what we want to say.

    Our languages are more than just means of communicating ideas. They presumably convey knowledge about the minds and societies that developed them. Some of these mechanisms are known to us, but others could be yet undiscovered by our own scholars. Extraterrestrials may know better. Furthermore, they could presumably conduct comparative linguistic studies with their own languages or those of other civilizations they have encountered.

    Furthermore, human languages are really a more open and direct way of saying what who we are. They are a part of us, and we should communicate our languages as much as we communicate anything else.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The primary objectives and purposes of METI International are to:

    Conduct scientific research and educational programs in Messaging Extraterrestrial Intelligence (METI) and the Search for Extraterrestrial Intelligence (SETI).

    Promote international cooperation and collaboration in METI, SETI, and astrobiology.

    Understand and communicate the societal implications and relevance of searching for life beyond Earth, even before detection of extraterrestrial life.

    Foster multidisciplinary research on the design and transmission of interstellar messages, building a global community of scholars from the natural sciences, social sciences, humanities, and arts.

    Research and communicate to the public the many factors that influence the origins, evolution, distribution, and future of life in the universe, with a special emphasis on the last three terms of the Drake Equation: (1) the fraction of life-bearing worlds on which intelligence evolves, (2) the fraction of intelligence-bearing worlds with civilizations having the capacity and motivation for interstellar communication, and (3) the longevity of such civilizations.

    Offer programs to the public and to the scholarly community that foster increased awareness of the challenges facing our civilization’s longevity, while encouraging individual and community activities that support the sustainability of human culture on multigenerational timescales, which is essential for long-term METI and SETI research.

     
  • richardmitnick 9:36 am on March 12, 2018 Permalink | Reply
    Tags: Astrobiology, , , , , Carbon-based molecules are a by-product of red giants, Circumstellar envelopes, , , , Red Giant Stars, U Hawaii Manoa   

    From University of Hawaii Manoa via COSMOS: “Complex organic compounds from dying stars could be life precursors” 

    U Hawaii

    University of Hawaii Manoa

    COSMOS

    12 March 2018
    Richard A. Lovett

    Lab experiments reveal carbon-based molecules are a by-product of red giants.

    1
    A red giant star – the font, perhaps, of life… QAI Publishing/UIG via Getty Images

    Laboratory experiments designed to recreate conditions around carbon-rich red giant stars have revealed that startlingly complex organic compounds can form in the “circumstellar envelopes” created by stellar winds blowing off from them.

    The carbon is present because nuclear reactions in these dying stars have progressed to the point that much of their initial complement of hydrogen and helium has been converted into heavier elements such as carbon.

    “There is a lot of carbon in these circumstellar envelopes,” says Ralf Kaiser, a physical chemist at the University of Hawaii at Manoa, US.

    In research published in the journal Nature Astronomy, a team led by Kaiser used a high-temperature chemical reactor to simulate conditions inside these circumstellar envelopes.

    The goal, he says, is to demonstrate how complex compounds can be assembled a couple of carbon atoms at a time at temperatures of up to about 1200 degrees Celsius. Previous research found that a host of organic chemicals can indeed be formed, but the new study pushed the process farther, demonstrating that it is possible to create chemicals at least as complex as pyrene, a 16-carbon compound with a structure like four fused benzene rings.

    So far, pyrene is the most complex molecule constructed in this manner, but Kaiser thinks that it might be just the beginning. “We hope when we do further experiments that this can be extended,” he says.

    What this means, he explains, is that circumstellar envelopes might be able to create molecules with 60 or 70 carbons, or even nanoparticle-sized sheets of graphene, a material composed of a larger array of fused rings.

    Such materials, he says, can act as building blocks on which other molecules, such as water, methane, methanol, carbon monoxide, and ammonia can condense as they move away from the star and cool to temperatures as low as minu-263 degrees Celsius. When the resulting chemical stew is exposed to ionising radiation either from nearby sources or galactic cosmic rays, Kaiser says, they can form sugars, amino acids, and dipeptides.

    “These are molecules relevant to the origins of life,” he adds.

    Billions of years ago, such organic-rich particles may have found their way into asteroids that then rained down onto the primordial Earth, endowing us with the precursors for life.

    Pyrene is a member of a family of compounds called polycyclic aromatic hydrocarbons (PAHs), the simplest of which is naphthalene, the primary ingredient of mothballs. Simple PAHs have already been detected in space, but the holy grail, Kaiser says, will be if more complex ones, such as pyrene, are found by NASA’s OSIRIS-REx mission, now en route to asteroid 101955 Bennu, from which it is expected to send back a sample in 2023.

    NASA OSIRIS-REx Spacecraft

    “We do not know what this mission will find,” Kaiser says. But, “if they find carbonaceous materials such as PAHs, then our experiments say how this organic matter can be formed.”

    Humberto Campins, a planetary scientist from Central Florida University, Orlando, Florida, and member of the OSIRIS REx science team, agrees. Studying the chemical makeup of asteroids, he says, doesn’t just tell us about the composition of our own early solar system, but can also reveal information about “pre-solar” compounds.

    “One of the beauties of sample return missions is that the latest analytical techniques for chemical, mineralogical, and isotopic composition can be applied to very small components of the sample, such as pre-solar grains or molecules,” he says.

    “We know that the dust from these kinds of stars gets incorporated into meteorites, so they are absolutely contributing to the compounds that would be present within Bennu,” adds Chris Bennett, also of the University of Central Florida (and a former student of Kaiser’s, although he was not part of the present study team).

    Chris McKay, an astrobiologist at NASA Ames Research Centre in Moffett Field, California, adds that the paper supports the notion that that the universe contains a large amount of carbon in the form of organic molecules. “[That’s] not a new result,” he says, “but [it is] further support for this key idea in astrobiology.”

    Kaiser adds that the finding demonstrates the value of interdisciplinary studies.

    “Most of the scientists dealing with PAHs [in space] are astronomers,” he says. “They are excellent spectroscopists, but by nature, astronomy sometimes lacks fundamental knowledge about chemistry.”

    Laboratory studies are necessary to turn theories for how complex chemicals can form in space from “hand-waving” into something more definitive, he says.

    But the interdisciplinary impact goes beyond astronomy. Pyrene and other PAHs are common pollutants that can be incorporated into dangerous soot particles created by internal combustion engines and other industrial processes.

    Lessons from astrochemistry about how they can be formed, he says, says Kaiser, can therefore have the very practical side effect of helping us develop less-polluting automobile engines.

    See the full article here .

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    System Overview

    The University of Hawai‘i System includes 10 campuses and dozens of educational, training and research centers across the Hawaiian Islands. As the public system of higher education in Hawai‘i, UH offers opportunities as unique and diverse as our Island home.

    The 10 UH campuses and educational centers on six Hawaiian Islands provide unique opportunities for both learning and recreation.

    UH is the State’s leading engine for economic growth and diversification, stimulating the local economy with jobs, research and skilled workers.

     
  • richardmitnick 12:53 pm on March 5, 2018 Permalink | Reply
    Tags: Astrobiology, , , , , , , Pyrene   

    From LBNL: “Chemical Sleuthing Unravels Possible Path to the Formation of Life’s Building Blocks in Space” 

    Berkeley Logo

    Berkeley Lab

    March 5, 2018
    Glenn Roberts Jr.
    geroberts@lbl.gov
    (510) 486-5582

    Experiments at Berkeley Lab’s Advanced Light Source reveal how a hydrocarbon called pyrene could form near stars.

    LBNL/ALS

    1
    The atomic structure of pyrene molecules (upper left and upper right) are represented in an artist’s rendering of an asteroid belt, with carbon atoms shown in black and hydrogen atoms in white. A new study shows chemical steps for how pyrene, a type of hydrocarbon found in some meteorite samples, could form in space. (Credit: NASA-JPL-Caltech, Wikimedia Commons).

    Scientists have used lab experiments to retrace the chemical steps leading to the creation of complex hydrocarbons in space, showing pathways to forming 2-D carbon-based nanostructures in a mix of heated gases.

    The latest study, which featured experiments at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), could help explain the presence of pyrene, which is a chemical compound known as a polycyclic aromatic hydrocarbon, and similar compounds in some meteorites.

    A team of scientists, including researchers from Berkeley Lab and UC Berkeley, participated in the study, published March 5 in the Nature Astronomy journal. The study was led by scientists at the University of Hawaii at Manoa and also involved theoretical chemists at Florida International University.

    “This is how we believe some of the first carbon-based structures evolved in the universe,” said Musahid Ahmed, a scientist in Berkeley Lab’s Chemical Sciences Division who joined other team members to perform experiments at Berkeley Lab’s Advanced Light Source (ALS).

    “Starting off from simple gases, you can generate one-dimensional and two-dimensional structures, and pyrene could lead you to 2-D graphene,” Ahmed said. “From there you can get to graphite, and the evolution of more complex chemistry begins.”

    Pyrene has a molecular structure composed of 16 carbon atoms and 10 hydrogen atoms. Researchers found that the same heated chemical processes that give rise to the formation of pyrene are also relevant to combustion processes in vehicle engines, for example, and the formation of soot particles.

    The latest study builds on earlier work that analyzed hydrocarbons with smaller molecular rings that have also been observed in space, including in Saturn’s moon Titan – namely benzene and naphthalene.

    Ralf I. Kaiser, one of the study’s lead authors and a chemistry professor at the University of Hawaii at Manoa, said, “When these hydrocarbons were first seen in space, people got very excited. There was the question of how they formed.” Were they purely formed through reactions in a mix of gases, or did they form on a watery surface, for example?

    Ahmed said there is an interplay between astronomers and chemists in this detective work that seeks to retell the story of how life’s chemical precursors formed in the universe.

    “We talk to astronomers a lot because we want their help in figuring out what’s out there,” Ahmed said, “and it informs us to think about how it got there.”

    Kaiser noted that physical chemists, on the other hand, can help shine a light on reaction mechanisms that can lead to the synthesis of specific molecules in space.

    2
    A researcher handles a fragment and a test tube sample of the Murchison meteorite, which has been shown to contain a a variety of hydrocarbons and amino acids, in this photo from a previous, unrelated study at Argonne National Laboratory. Experiments at Berkeley Lab are helping to retrace the chemical steps by which complex hydrocarbons like pyrene could form in the Murchison meteorite and other meteorites. (Credit: Argonne National Laboratory)

    Pyrene belongs to a family known as polycyclic aromatic hydrocarbons, or PAHs, that are estimated to account for about 20 percent of all carbon in our galaxy. PAHs are organic molecules that are composed of a sequence of fused molecular rings. To explore how these rings develop in space, scientists work to synthesize these molecules and other surrounding molecules known to exist in space.

    Alexander M. Mebel, a chemistry professor at Florida International University who participated in the study, said, “You build them up one ring at a time, and we’ve been making these rings bigger and bigger. This is a very reductionist way of looking at the origins of life: one building block at a time.”

    For this study, researchers explored the chemical reactions stemming from a combination of a complex hydrocarbon known as the 4-phenanthrenyl radical, which has a molecular structure that includes a sequence of three rings and contains a total of 14 carbon atoms and nine hydrogen atoms, with acetylene (two carbon atoms and two hydrogen atoms).

    Chemical compounds needed for the study were not commercially available, said Felix Fischer, an assistant professor of chemistry at UC Berkeley who also contributed to the study, so his lab prepared the samples. “These chemicals are very tedious to synthesize in the laboratory,” he said.

    At the ALS, researchers injected the gas mixture into a microreactor that heated the sample to a high temperature to simulate the proximity of a star. The ALS generates beams of light, from infrared to X-ray wavelengths, to support a range of science experiments by visiting and in-house researchers.

    The mixture of gases was jetted out of the microreactor through a tiny nozzle at supersonic speeds, arresting the active chemistry within the heated cell. The research team then focused a beam of vacuum ultraviolet light from the synchrotron on the heated gas mixture that knocked away electrons (an effect known as ionization).

    They then analyzed the chemistry taking place using a charged-particle detector that measured the varied arrival times of particles that formed after ionization. These arrival times carried the telltale signatures of the parent molecules. These experimental measurements, coupled with Mebel’s theoretical calculations, helped researchers to see the intermediate steps of the chemistry at play and to confirm the production of pyrene in the reactions.

    Mebel’s work showed how pyrene (a four-ringed molecular structure) could develop from a compound known as phenanthrene (a three-ringed structure). These theoretical calculations can be useful for studying a variety of phenomena, “from combustion flames on Earth to outflows of carbon stars and the interstellar medium,” Mebel said.

    Kaiser added, “Future studies could study how to create even larger chains of ringed molecules using the same technique, and to explore how to form graphene from pyrene chemistry.”

    3
    A reaction pathway that can form a hydrocarbon called pyrene through a chemical method known as hydrogen-abstraction/acetylene-addition, or HACA, is shown at the top. At bottom, some possible steps by which pyrene can form more complex hydrocarbons via HACA (red) or another mechanism (blue) called hydrogen abstraction – vinylacetylene addition (HAVA). (Credit: Long Zhao, Ralf I. Kaiser, et al./Nature Astronomy, DOI: 10.1038/s41550-018-0399-y)

    Other experiments conducted by team members at the University of Hawaii will explore what happens when researchers mix hydrocarbon gases in icy conditions and simulate cosmic radiation to see whether that may spark the creation of life-bearing molecules.

    “Is this enough of a trigger?” Ahmed said. “There has to be some self-organization and self-assembly involved” to create life forms. “The big question is whether this is something that, inherently, the laws of physics do allow.”

    The study was supported by the U.S. Department of Energy’s Office Sciences, and UC Berkeley, the University of Hawaii, Florida International University, and the National Science Foundation.

    The ALS is a DOE Office of Science User Facility.

    See the full article here .

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  • richardmitnick 8:33 am on October 19, 2017 Permalink | Reply
    Tags: All important research in what is a chipping away of the many unknowns in the stories of the origins of Earth and the origin of life, , Astrobiology, Flow of electrons (electricity) from the core of the Earth, Geobiochemistry, , ,   

    From Many Worlds: “2.5 Billions Years of Earth History in 100 Square Feet’ 

    NASA NExSS bloc

    NASA NExSS

    Many Words icon

    Many Worlds

    2017-10-19
    Marc Kaufman

    1
    Scalding hot water from an underground thermal spring creates an iron-rich environment similar to what existed on Earth 2.5 billion years ago. (Nerissa Escanlar)

    Along the edge of an inlet on a tiny Japanese island can be found– side by side – striking examples of conditions on Earth some 2.4 billion years ago, then 1.4 billion years ago and then the Philippine Sea of today.

    First is a small channel with iron red, steaming and largely oxygen-free water – filled from below with bubbling liquid above 160 degrees F. This was Earth as it would have existed, in a general way, as oxygen was becoming more prevalent on our planet some 2.4 billion years ago. Microbes exist, but life is spare at best.

    Right next to this ancient scene is region of green-red water filled with cyanobacteria – the single-cell creatures that helped bring masses of oxygen into our atmosphere and oceans. Locals come to this natural “onsen” for traditional hot baths, but they have to make their way carefully because the rocky floor is slippery with green mats of the bacteria.

    And then there is the Philippine Sea, cool but with spurts of warm water shooting up from below into the cove.

    All of this within a area of maybe 100 square feet.

    It is a unique hydrothermal scene, and one recently studied by two researchers from the Earth-Life Science Institute in Tokyo – microbiologist Shawn McGlynn and ancient virus specialist Tomohiro Mochizuki.

    They were taking measurements of temperature, salinity and more, as well as samples of the hot gas and of microbial life in the iron-red water. Cyanobacterial mats are collected in the greener water, along with other visible microbe worlds.

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    Microbiologist Shawn McGlynn of the Earth Life Science Institute in Tokyo scoops some iron-rich water from a channel on Shikine-jima Island, 100 miles from Tokyo. (Nerissa Escanlar)

    The scientific goals are to answer specific questions – are the bubbles the results of biology or of geochemical processes? What are the isotopic signatures of the gases? What microbes and viruses live in the super-hot sections? And can cyanobacteria and iron co-exist?

    All are connected, though, within the broad scientific effort underway to ever more specifically understand conditions on Earth through the eons, and how those conditions can help answer fundamental questions of how life might have begun.

    “We really don’t know what microbiology looked like 2.5 billion or 1.5 billion years ago,” said McGlynn, “But this is a place we can go where we can try to find out. It’s a remarkable site for going back in time.”

    In particular, there are not many natural environments with high levels of dissolved iron like this site. Yet scientists know from the rock record that there were periods of Earth history when the oceans were similarly filled with iron.

    Mochizuki elaborated: “We’re trying to figure out what was possible chemically and biologically under certain conditions long ago.

    “If you have something happening now at this unusual place – with the oxygen and iron mixing in the hot water to turn the water red – then there’s a chance that what we find today was there as well billions of years ago. ”

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    Tomohiro Mochizuki at collecting samples directly from the spot where 160 degree F water pushes up through the rock at Jinata hot spring. (Nerissa Escanlar)

    The Jinata hot springs, as the area is known, is on Shikine-jima Island, one of the furthest out in the Izu chain of islands that starts in Tokyo Bay. More than 100 miles from Tokyo itself, Shikine-jima is nonetheless part of Tokyo Prefecture.

    The Izu islands are all volcanic, created by the underwater movements of the Philippine and Pacific tectonic plates. That boundary remains in flux, and thus the hot springs and volcanoes. The terrain can be pretty rugged: in English, Jinata translates to something like Earth Hatchet, since the hot spring is at the end of a path through what does look like a rock rising that had been cut through with a hatchet.

    Hot springs and underwater thermal vents have loomed large in thinking about origins of life since it became known in recent decades that both generally support abundant life – microbial and larger – and supply nutrients and even energy in the form of electricity from vents and electron transfers from chemical reactions.

    And so not surprisingly, vents are visited and sampled not infrequently by ELSI scientists. McGlynn was on another hydrothermal vent field trip in Iceland over the summer with, among others, ELSI Origins Network fellow Donato Gionovelli and ELSI principal investigator and electrochemist Ruyhei Nakamura..

    McGlynn’s work is focused on how electrons flow between elements and compounds, a transfer that he sees as a basic architecture for all life. With so many compelling flows occurring in such a small space, Jinata is a superb laboratory.

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    The volcanic Izu island chain, starting in Tokyo Bay and going out into the Philippine Sea.

    For Mochizuki, the site turned out to be exciting but definitely not a goldmine. That’s because his speciality is viruses that live at very high temperatures, and even the bubbling hot spring in the iron trench measured about 73 degrees C (163 degrees F.) The viruses he incubates live at temperatures between closer to 90 C (194 F), not far from the boiling point.

    His goal in studying these high-temperature (hyperthermophilic) viruses is to look back to the earliest days of life forming on Earth, using viruses as his navigators. Since life is thought by many scientists to have begun in a super hot RNA world, Mochizuki wants to look at viruses still living in those conditions today to see what they can tell us.

    So far, he explained, what they have told us is that the RNA in the earliest lifeforms on Earth – denizens of the Archaean kingdom – did not have viruses. And this is puzzling.

    So Mochizuki is always interested in going to sample hot springs and thermal vents to collect high temperature viruses, and to look for surprises.

    Though the bubbling waters were so hot that both researchers had difficulty standing in the water with boots on and holding their collection vials with gloves, it was not hot enough for what Mochizuki is after. But that certainly didn’t stop him from taking as many samples as he could, including some for other ELSI researchers doing different work but still needing interesting samples.

    Researchers often need to be inventive on field trips, and that was certainly the case at Jinata. When McGlynn first tried to sample the bubbles at the scalding spring, his hands and feet quickly felt on fire and he had to retreat.

    To speed the process, he and Mochizuki built a funnel out of a large plastic water bottle, a device that allowed the bubbles to be collected and directed into the sample vial without the gloved hands being so close to the heat. The booted feet, however, remained a problem and the heat just had to be endured.

    Nearby the steaming bubbling of the hot spring were collections of what appeared to be fine etchings on the bottom of the red channel. These faint designs, McGlynn explained, were the product of a microbe that makes it’s way along the bottom and deposits lines of processed iron oxide as it goes. So while the elegant designs are not organic, the creatures that creates them surely is.

    “Touch the area and the lines go poof,” McGlynn said. “That’s because they’re just the iron oxide; nothing more. Next to us is the water with much less iron and a lot more oxygen, and so there are blooms of (green) cyanobacteria. Touch them and they don’t go poof, they stick to your hand because they’re alive.”

    5
    Patterns created by microbes as they deposit iron oxide at the bottom of small channel. (Marc Kaufman)

    McGlynn also collects some of the the poofs to get at the microbes making the unusual etchings. It may be a microbe never identified before.

    As a microbiologist, he is of course interested in identifying and classifying microbes. He initially thought the microbes in the iron channel would be anaerobic, but he found that even tiny amount of oxygen making their way into the springs from the atmosphere made most aerobic, or possibly anaerobes capable of surviving with oxygen (which usually is toxic to them.)

    He also found that laboratory studies that found cyanobacteria would not flourish in the presence of iron were not accurate in nature, or certainly were not accurate at Jinata onsen.

    But it is that flow of electrons that really drives McGlynn – he even dreams of them at night, he told me.

    One of the goals of his work, and that of his colleague and sometimes collaborator at ELSI, geobiochemist Yuichiro Ueno, is to answer some of the outstanding questions about that flow of electrons (electricity) from the core of the Earth. The energy transits through the mantle, to the surface and then often is in contact with the biosphere (all living things) before it enters the atmosphere and sometimes disappears into space.

    He likened the process to the workings of a gigantic battery, with the iron core as the cathode and the oxygen in the atmosphere as the anode. Understanding the chemical pathways traveled by the electrons today, he is convinced, will tell a great deal about conditions on the early Earth as well.

    It’s all important research in what is a chipping away of the many unknowns in the stories of the origins of Earth and the origin of life.

    6
    A boundary between where the very hot iron-rich water meets and the less hot water with thriving cyanobacteria colonies at Jinata.

    The field work also illustrated the hit-and-miss nature of these kind of outings. While McGlynn has not come up with Jinata surprises or novel understandings, he was so taken with the setting that he wondered if a seemly empty building not too far from the site could be turned into an ELSI marine lab.

    And while Mochizuki did not find sufficiently hot water for his work, he might still be coming back to the island, or others nearby. That’s because he learned of a potentially much hotter spring at a spot where the sea hits one of the island’s steep cliffs – a site that requires boat access that was unsafe in the choppy waters during this particular visit.

    In addition, McGlynn and Mochizuki did make some surprising discoveries, though they didn’t involve microbes, electron transfer or viruses.

    During a morning visit to a different hot spring, they came across a team of what turned out to be officials of the Izu islands – all dressed in suits and ties. They were visiting Shikine-jima as part of a series of joint islands visit to assess economic development opportunities.

    The officials were intrigued to learn what the scientists were up to, and made some suggestions of other spots to sample. One was an island occupied by Japanese self-defense forces and generally closed to outsiders. But the island is known to have areas of extremely hot water just below the surface of the land, sometimes up to 100 C (212 F.)

    The officials gave their cards and told the scientists to contact them if they wanted to get onto that island for sampling. And as for the official from Shikine-jima, he was already thinking big.

    “It would be a very good thing,” he said, “if you found the origin of life on our island.

    See the full article here .

    Please help promote STEM in your local schools.

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    About Many Worlds

    There are many worlds out there waiting to fire your imagination.

    Marc Kaufman is an experienced journalist, having spent three decades at The Washington Post and The Philadelphia Inquirer, and is the author of two books on searching for life and planetary habitability. While the “Many Worlds” column is supported by the Lunar Planetary Institute/USRA and informed by NASA’s NExSS initiative, any opinions expressed are the author’s alone.

    This site is for everyone interested in the burgeoning field of exoplanet detection and research, from the general public to scientists in the field. It will present columns, news stories and in-depth features, as well as the work of guest writers.

    About NExSS

    The Nexus for Exoplanet System Science (NExSS) is a NASA research coordination network dedicated to the study of planetary habitability. The goals of NExSS are to investigate the diversity of exoplanets and to learn how their history, geology, and climate interact to create the conditions for life. NExSS investigators also strive to put planets into an architectural context — as solar systems built over the eons through dynamical processes and sculpted by stars. Based on our understanding of our own solar system and habitable planet Earth, researchers in the network aim to identify where habitable niches are most likely to occur, which planets are most likely to be habitable. Leveraging current NASA investments in research and missions, NExSS will accelerate the discovery and characterization of other potentially life-bearing worlds in the galaxy, using a systems science approach.
    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

     
  • richardmitnick 8:26 am on October 17, 2017 Permalink | Reply
    Tags: , Astrobiology, , Rosalba Bonnacorsi, , Underground Laboratories for Dark Matter Research,   

    From SETI Institute: Women in STEM -“Catch Up with SETI Institute Scientist Rosalba Bonnacorsi on her NASA Spaceward Bound Expedition to the Center of the Earth (Almost!) 

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    SETI Institute Astrobiology Scientist Rosalba Bonnacorsi

    October 16, 2017

    For two weeks in October, from the 8th-20th, SETI Institute scientist Rosalba Bonnacorsi will be part of the expedition team when NASA Spaceward Bound and the U.K. Centre for Astrobiology conduct a planetary analog expedition in the Boulby Mine. Boulby is the site of the astrobiology analog research with the Mine Analog Research Program (MINAR)

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    The Boulby International Subsurface Astrobiology Laboratory (BISAL) is hosted by the Boulby Mine complex north of Whitby, Yorkshire, on the North East coast of England (UK).

    The Boulby Mine is a 1.1 km-deep active potash mine at the core of a 250-million-year-old, massive sequence of NaCl, KCl, and sulfates salts. The salts were formed by the evaporation of an ancient ocean – the Zechstein Sea — which covered most of present day Western Europe during the Permian geologic period. The facility comprises over 1,000 km of underground roadways through the salt deposits. BISAL is a fully air conditioned, internet connected to the surface (100 Mbps) laboratory, with an outside ‘Mars yard’ for testing rover and instrument technology. The facility is also used for studies of astrophysics – the Underground Laboratories for Dark Matter Research, and low-background radiation and other deep underground science.

    The expedition is made up of an international team of scientists, teachers, engineers, biologists, geologists and astronauts. Scientists and educators from NASA and the SETI Institute will work on a variety of science and technology projects which will address some specific scientific questions and test a variety of potential technologies and planetary exploration protocols in the mine:

    Scientific Questions:

    Does ancient salt preserve viable organisms?
    What biosignatures of life are preserved in deep salts?
    What types of organisms inhabit deep brines?
    What are the environmental conditions that support life in salt?
    What is the composition and structure of evaporite deposits?
    Where does the deep subsurface gas comes from? Is this from biology or from geology?
    How we can apply what we learn in MINAR5 to the search for past and present life on other planets?

    Testing:

    Life detection technology
    Clean sampling technologies
    Autonomous drones and rover technology for deep subsurface exploration and mapping on the Moon and Mars
    Gas detection technology
    Communication protocols with the surface to simulate cave and lava tube exploration on the Moon and Mars

    3
    Entrance to the mine (Image Credit: Boulby Mine)

    The team will explore and study a variety of ancient salt structures and briny environments. The primary objectives are to detect evidence of ancient and modern life inside the salt and to monitor the associated underground microclimate (temperature and rH). They will scout Boulby’s underworld, and test for the most efficient protocols for accepting sampling as well as in situ and laboratory analysis of collected samples. Furthermore, they will conduct technology/robotic experiments to simulate drilling missions in space conducted by Astronauts.

    Spaceward Bound is an educational program and will use the lab and mine environment to carry out science and technology in support of the subsurface exploration of the Moon and Mars, and Ocean Worlds. Exploration, hand-on activities and classroom work will be conducted during the day. A typical day will involve a 101 introductory lectures-lab, safety training sessions, and morning/evening group meetings to plan together the next day science objectives and tasks, as well as discuss on what we have learned during the day.

    Rosalba has worked as an Astrobiologist at the Carl Sagan Center of the SETI Institute since 2008 and with scientists at NASA Ames Research Center since 2005. She enjoys doing science to advance our understanding of the universe and spends much of her spare time raising public awareness about planetary analog research taking place on Earth, including associated space missions to the Solar System (such as the Mars Science Lab 2020) and those planned to reach potential life in ocean worlds (e.g., Saturn’s icy moon Enceladus). Rosalba’s goal is to gain a broad picture of where life and its signatures are most successfully distributed, concentrated, preserved, and detected. This knowledge helps us to understand how to search for life beyond Earth.

    The SETI Institute is proud to collaborate and support the NASA Spaceward Bound Expedition to Boulby Mine, this October.

    See the full article here .

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  • richardmitnick 2:48 pm on July 6, 2017 Permalink | Reply
    Tags: Astrobiology, , , , Certain Big, Charged Molecules Are Universal to Life. Can They Help Detect It Elsewhere in the Solar System?, ,   

    From Many Worlds: “Certain Big, Charged Molecules Are Universal to Life. Can They Help Detect It Elsewhere in the Solar System?” 

    NASA NExSS bloc

    NASA NExSS

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    Many Worlds

    2017-07-06
    Marc Kaufman

    1
    NASA’s Cassini spacecraft completed its deepest-ever dive through the icy plume of Enceladus on Oct. 28, 2015. The spacecraft did not have instruments that could detect life, but missions competing for NASA New Frontiers funding will — raising the thorny question of how life might be detected. (NASA/JPL-Caltech)

    As NASA inches closer to launching new missions to the Solar System’s outer moons in search of life, scientists are renewing their focus on developing a set of universal characteristics of life that can be measured.

    There is much debate about what might be considered a clear sign of life, in part, because there are so many definitions separating the animate from the inanimate.

    NASA’s prospective missions to promising spots on Europa, Enceladus and Titan have their individual approaches to detecting life, but one respected voice in the field says there is a better way that’s far less prone to false positives.

    Noted chemist and astrobiologist Steven Benner says life’s signature is not necessarily found in the presence of particular elements and compounds, nor in its effects on the surrounding environment, and is certainly not something visible to the naked eye (or even a sophisticated camera).

    Rather, life can be viewed as a structure, a molecular backbone that Benner and his group, Foundation for Applied Molecular Evolution (FfAME), have identified as the common inheritance of all living things. Its central function is to enable what origin-of-life scientists generally see as an essential dynamic in the onset of life and its increased complexity and spread: Darwinian evolution via transfer of information, mutation and the transfer of those mutations.

    “What we’re looking for is a universal molecular bio-signature, and it does exist in water,” says Benner. “You want a genetic molecule that can change physical conditions without changing physical properties — like DNA and RNA can do.”

    2
    Steven Benner, director of the Foundation for Applied Molecular Evolution or FfAME. (SETI)

    Looking for DNA or RNA on an icy moon, or elsewhere would presuppose life like our own — and life that has already done quite a bit of evolving.

    A more general approach is to find a linear polymer (a large molecule, or macromolecule, composed of many repeated subunits, of which DNA and RNA are types) with an electrical charge. That, he said, is a structure that is universal to life, and it can be detected.

    As described in a recent paper that Benner’s group published in the journal Astrobiology: “the only molecular systems able to support Darwinian information are linear polymers that have a repeating backbone charge. These are called ‘polyelectrolytes.’

    “These data suggest that polyelectrolytes will be the genetic molecules in all life, no matter what its origin and no matter what the direction or tempo of its natural history, as long as it lives in water.”

    Through years of experimentation, Benner and others have found that electric charges in these crucial polymers, or “backbones,” of life have to repeat. If they are a mixture of positive and negative charges, then the ability to pass on changing information without the structure itself changing is lost.

    And as a result, Benner says, detecting these charged, linear and repeating large molecules is potentially quite possible on Europa or Enceladus or wherever water is found. All you have to do is expose those charged and repeating molecular structures to an instrument with the opposite charge and measure the reaction.

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    Polyelectrolytes are long-chain, molecular semiconductors, whose backbones contain electrons. The structure and composition of the polyelectrolytes confers an ability to transfer electric charge and the energy of electronic excited states over distance. (Azyner Group, UCSC)

    James Green, director of NASA’s Planetary Sciences division, sees values in this approach.

    “Benner’s polyelectrolyte study is fascinating to me since it provides our scientists another critical discussion point about finding life with some small number of experiments,” he says.

    “Finding life is very high bar to cross; it has to metabolize, reproduce, and evolve — all of which I can’t develop an experiment to measure on another planet or moon. If it doesn’t talk or move in front of the camera we are left with developing a very challenging set of instruments that can only measure attributes. So polyelectrolytes are one more to consider.”

    Benner has been describing his universal molecular bio-signature to leaders of the groups competing for New Frontiers missions, which fill the gap between smaller Discovery missions and large flagship planetary missions. It’s taken a while but due to his efforts over several years, he notes that interest seems to be growing in incorporating his findings.

    4
    Astrobiologist Chris McKay at NASA’s Ames Research Center. (IDG News Service)

    In particular, Chris McKay, a prominent astrobiologist at NASA’s Ames Research Center and a member of one of the New Frontiers Enceladus proposal teams, says he thinks there is merit to Benner’s idea.

    “The really interesting aspect of this suggestion is that new technologies are now available for sequencing DNA that can be generalized to read any linear molecule,” McKay writes in an email.

    In other words, they can detect any polyelectrolytes.

    Other teams are confident that their own kinds of life detection instruments can do the job. Morgan Cable, deputy project scientist of the Enceladus Life Finder proposal, she says her team has great confidence in its four-pronged approach. A motto of the mission on some of its written material is: “If Encedadus has life, we will find it.”

    The package includes instruments like mass spectrometers able to detect large molecules associated with life; measurements of energy gradients that allow life to be nourished; detection of isotopic signatures associated with life; and identification of long carbon chains that serve as membranes to house the components of a cell.

    “Not one but all four indicators have to point to life to make a potential detection,” Cable says.

    NASA is winnowing down 12 proposals by late this year, so, Benner’s ideas could play a role later in the process as well. NASA’s goal is to select its next New Frontiers mission in about two years, with launch in the mid-2020s.

    The Europa Clipper orbiter mission is tentatively scheduled to launch in 2022, but its companion lander has been scrubbed for now by the Trump administration.

    Nonetheless, NASA put out a call last month for instruments that might one day sample the ice of Europa. Benner is once more hoping that his theory of polyelectrolytes as the key to identifying life in water or ice will be considered and embraced.

    5
    These composite images show a suspected plume of material erupting two years apart from the same location on Jupiter’s icy moon Europa. Both plumes, photographed in UV light by Hubble, were seen in silhouette as the moon passed in front of Jupiter. Europa is a major focus of the search for life beyond Earth. (NASA/ESA/STScI/USGS)

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    About Many Worlds

    There are many worlds out there waiting to fire your imagination.

    Marc Kaufman is an experienced journalist, having spent three decades at The Washington Post and The Philadelphia Inquirer, and is the author of two books on searching for life and planetary habitability. While the “Many Worlds” column is supported by the Lunar Planetary Institute/USRA and informed by NASA’s NExSS initiative, any opinions expressed are the author’s alone.

    This site is for everyone interested in the burgeoning field of exoplanet detection and research, from the general public to scientists in the field. It will present columns, news stories and in-depth features, as well as the work of guest writers.

    About NExSS

    The Nexus for Exoplanet System Science (NExSS) is a NASA research coordination network dedicated to the study of planetary habitability. The goals of NExSS are to investigate the diversity of exoplanets and to learn how their history, geology, and climate interact to create the conditions for life. NExSS investigators also strive to put planets into an architectural context — as solar systems built over the eons through dynamical processes and sculpted by stars. Based on our understanding of our own solar system and habitable planet Earth, researchers in the network aim to identify where habitable niches are most likely to occur, which planets are most likely to be habitable. Leveraging current NASA investments in research and missions, NExSS will accelerate the discovery and characterization of other potentially life-bearing worlds in the galaxy, using a systems science approach.
    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

     
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