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  • richardmitnick 5:36 pm on January 10, 2018 Permalink | Reply
    Tags: , , , , , , , , or, , STXM-scanning transmission X-ray microscope, We’re looking at the organic ingredients that can lead to the origin of life” including the amino acids needed to form proteins,   

    From LBNL: “Ingredients for Life Revealed in Meteorites That Fell to Earth” 

    Berkeley Logo

    Berkeley Lab

    January 10, 2018
    Glenn Roberts Jr.
    geroberts@lbl.gov
    (510) 486-5582

    1
    A blue crystal recovered from a meteorite that fell near Morocco in 1998. The scale bar represents 200 microns (millionths of a meter). (Credit: Queenie Chan/The Open University, U.K.)

    Two wayward space rocks, which separately crashed to Earth in 1998 after circulating in our solar system’s asteroid belt for billions of years, share something else in common: the ingredients for life. They are the first meteorites found to contain both liquid water and a mix of complex organic compounds such as hydrocarbons and amino acids.

    A detailed study of the chemical makeup within tiny blue and purple salt crystals sampled from these meteorites, which included results from X-ray experiments at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), also found evidence for the pair’s past intermingling and likely parents. These include Ceres, a brown dwarf planet that is the largest object in the asteroid belt, and the asteroid Hebe, a major source of meteorites that fall on Earth.

    The study, published Jan. 10 in the journal Science Advances, provides the first comprehensive chemical exploration of organic matter and liquid water in salt crystals found in Earth-impacting meteorites. The study treads new ground in the narrative of our solar system’s early history and asteroid geology while surfacing exciting possibilities for the existence of life elsewhere in Earth’s neighborhood.

    “It’s like a fly in amber,” said David Kilcoyne, a scientist at Berkeley Lab’s Advanced Light Source (ALS), which provided X-rays that were used to scan the samples’ organic chemical components, including carbon, oxygen, and nitrogen.

    LBNL/ALS

    Kilcoyne was part of the international research team that prepared the study.

    While the rich deposits of organic remnants recovered from the meteorites don’t provide any proof of life outside of Earth, Kilcoyne said the meteorites’ encapsulation of rich chemistry is analogous to the preservation of prehistoric insects in solidified sap droplets.

    Queenie Chan, a planetary scientist and postdoctoral research associate at The Open University in the U.K. who was the study’s lead author, said, “This is really the first time we have found abundant organic matter also associated with liquid water that is really crucial to the origin of life and the origin of complex organic compounds in space.”

    She added, “We’re looking at the organic ingredients that can lead to the origin of life,” including the amino acids needed to form proteins.

    If life did exist in some form in the early solar system, the study notes that these salt crystal-containing meteorites raise the “possibility of trapping life and/or biomolecules” within their salt crystals. The crystals carried microscopic traces of water that is believed to date back to the infancy of our solar system – about 4.5 billion years ago.

    Chan said the similarity of the crystals found in the meteorites – one of which smashed into the ground near a children’s basketball game in Texas in March 1998 and the other which hit near Morocco in August 1998 – suggest that their asteroid hosts may have crossed paths and mixed materials.

    There are also structural clues of an impact – perhaps by a small asteroid fragment impacting a larger asteroid, Chan said.

    This opens up many possibilities for how organic matter may be passed from one host to another in space, and scientists may need to rethink the processes that led to the complex suite of organic compounds on these meteorites.

    “Things are not as simple as we thought they were,” Chan said.

    There are also clues, based on the organic chemistry and space observations, that the crystals may have originally been seeded by ice- or water-spewing volcanic activity on Ceres, she said.

    “Everything leads to the conclusion that the origin of life is really possible elsewhere,” Chan said. “There is a great range of organic compounds within these meteorites, including a very primitive type of organics that likely represent the early solar system’s organic composition.”

    Chan said the two meteorites that yielded the 2-millimeter-sized salt crystals were carefully preserved at NASA’s Johnson Space Center in Texas, and the tiny crystals containing organic solids and water traces measure just a fraction of the width of a human hair. Chan meticulously collected these crystals in a dust-controlled room, splitting off tiny sample fragments with metal instruments resembling dental picks.

    2
    These ALS X-ray images show organic matter (magenta, bottom) sampled from a meteorite, and carbon (top). (Credit: Berkeley Lab)

    “What makes our analysis so special is that we combined a lot of different state-of-the-art techniques to comprehensively study the organic components of these tiny salt crystals,” Chan said.

    Yoko Kebukawa, an associate professor of engineering at Yokohama National University in Japan, carried out experiments for the study at Berkeley Lab’s ALS in May 2016 with Aiko Nakato, a postdoctoral researcher at Kyoto University in Japan. Kilcoyne helped to train the researchers to use the ALS X-ray beamline and microscope.

    The beamline equipped with this X-ray microscope (a scanning transmission X-ray microscope, or STXM) is used in combination with a technique known as XANES (X-ray absorption near edge structure spectroscopy) to measure the presence of specific elements with a precision of tens of nanometers (tens of billionths of a meter).

    “We revealed that the organic matter was somewhat similar to that found in primitive meteorites, but contained more oxygen-bearing chemistry,” Kebukawa said. “Combined with other evidence, the results support the idea that the organic matter originated from a water-rich, or previously water-rich parent body – an ocean world in the early solar system, possibly Ceres.”

    Kebukawa also used the same STXM technique to study samples at the Photon Factory, a research site in Japan. And the research team enlisted a variety of other chemical experimental techniques to explore the samples’ makeup in different ways and at different scales.

    Chan noted that there are some other well-preserved crystals from the meteorites that haven’t yet been studied, and there are plans for follow-up studies to identify if any of those crystals may also contain water and complex organic molecules.

    3
    Ceres, a dwarf planet in the asteroid belt pictured here in this false-color image, may be the source of organic matter found in two meteorites that crashed to Earth in 1998. (Credit: NASA)

    Kebukawa said she looks forward to continuing studies of these samples at the ALS and other sites: “We may find more variations in organic chemistry.”

    The Advanced Light Source is a DOE Office of Science User Facility.

    Scientists at NASA Johnson Space Center, Kochi Institute for Core Sample Research in Japan, Carnegie Institution of Washington, Hiroshima University, The University of Tokyo, the High-Energy Accelerator Research Organization (KEK) in Japan, and The Graduate University for Advanced Studies (SOKENDAI) in Japan also participated in the study. The work was supported by the U.S. DOE Office of Science, the Universities Space Research Association, NASA, the National Institutes of Natural Sciences in Japan, Japan Society for the Promotion of Science, and The Mitsubishi Foundation.

    See the full article here .

    Please help promote STEM in your local schools.

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  • richardmitnick 7:16 am on May 30, 2017 Permalink | Reply
    Tags: , , , , , or, TEM-Hitachi transmission electron microscope, , UA Has the Tools to Analyze Asteroid's Dirt   

    From U Arizona: “UA Has the Tools to Analyze Asteroid’s Dirt” 

    U Arizona bloc

    University of Arizona

    May 26, 2017
    Emily Litvack

    1
    In the basement of a building constructed with NASA funds in the early 1960s, scientists already are preparing to study the sample from OSIRIS-REx, a first-of-its-kind mission.

    NASA OSIRIS-REx Spacecraft

    NASA OSIRIS REX FEROS

    NASA OSIRIS REX OTES

    NASA OSIRIS-REX OVIRS

    NASA OSIRIS REX OLA

    In the year 2023, priceless property will land somewhere in the Utah desert. And when it does, a team of engineers and scientists will be waiting on the ground. Thousands will watch the landing with eyes glued to smartphones and televisions. Headlines around the world will tell of the journey.

    The property? Between 2 and 70 ounces of asteroid dirt.

    This 4.5-billion-year-old sample, formally known as regolith, will look like a small pile of dusty rubble, gleaned in the five-second moment during which NASA’s OSIRIS-REx spacecraft vacuumed the surface of a carbon-rich, near-Earth asteroid called Bennu.

    The sample’s encapsulated landing at the Utah Test and Training Range, about 80 miles west of Salt Lake City, will begin a new phase in its existence: analysis. After being transported to the Johnson Space Center in Houston, the dirt will be removed from its capsule and allocated to scientists for study.

    1
    Tom Zega sits at the Hitachi transmission electron microscope, or TEM, in the Kuiper Space Sciences Building. The TEM was funded jointly by the National Science Foundation and NASA. (Photo: Mari Cleven/UA Office of Research, Discovery and Innovation)

    OSIRIS-REx is the first U.S. mission to return an asteroid sample to Earth, but for scientists such as Tom Zega, the return is just the beginning. Zega is a sample scientist at the University of Arizona. As a collaborator on the UA-led OSIRIS-REx mission, he will be one of the first scientists to analyze regolith from Bennu.

    One of the main goals of the OSIRIS-REx mission, Zega says, is understanding the earliest history of our solar system and the origins of life. Pristine regolith from an asteroid might be our best shot, untouched and uncontaminated by our atmosphere.

    “Sample return is great because otherwise you’re at the mercy of what falls from the sky,” Zega said. “Sample return is a treasure trove of information. You’re getting samples that are older than Earth. I can literally hold in my hand a piece of the origins of our solar system that predated Earth, predated human beings, predated everything we know.

    “These are atoms that assembled four and a half billion years ago and became the building blocks of our planet.”

    The question, then, is what to do with such a scientifically valuable pile of dirt.

    Building a Lab Fit for Analysis

    Analysis means two things — both of which require large equipment in a stable environment. The first: high-resolution imaging. The second: measuring chemistry. Respectively, those answer the questions “What does it look like?” and “What is it made of?”

    “We’re sort of like forensic scientists,” Zega says. “Nature grew these materials, and we’re analyzing it at a fundamental level to figure out under what conditions.”

    Zega does his work in the 5,000-square-foot basement of the Kuiper Space Sciences Building, constructed at the UA in 1964 with funds from NASA. The basement once was a mirror lab for telescopes and a publications vault. Telescopes got bigger, and so did the lab, which now lives beneath Arizona Stadium. Publications went online. Now the UA’s collection of high-tech electron microscopes — to be used for studying the returned asteroid dirt — lives here.

    Sensitive to stimulus, electron microscopes need a place with minimal vibrations, minimal electromagnetic interference and good acoustics. As it turns out, basements make good places for these microscopes. As of today, the lab is “ready to hit the ground running” when the sample from OSIRIS-REx shows up, according to Zega.

    In fact, the lab is in the process of studying a sample from Hayabusa 1, an asteroid sample return mission by JAXA, the Japanese equivalent of NASA. Like OSIRIS-REx, Hayabusa 2 is now cruising toward its target, which is the asteroid Ryugu.

    Zega opens the two frosted doors of the laboratory, revealing a long, clean, fluorescent-lit corridor.

    At the end of the corridor in a room on the left is where the asteroid sample’s time in the lab will truly begin. After it’s mounted on a glass slide and polished smooth, Zega will place the sample in an electron microprobe.

    “The microprobe gives us the most context, and a lay of the land,” Zega says.

    It allows him to photograph the entire sample in high resolution and map out its chemistry, element by element. Those elements, such as iron and nickel and magnesium, show up as colors on a computer screen.

    “You want to sit down and really process that data,” Zega says. “You might want to play around with the maps and overlay them onto the high-res images that you also created before you decide what the next step is. That can take some time.

    “You really want to take your time here before going on to a more detailed level of analysis.”

    Then, all the way at the other end of the corridor, near the doorway, there are two scanning electron microscopes. Like the microprobe, they also image and chemically map the sample, but at an even more detailed level. Here, Zega can look at the dirt in micrometers and nanometers — a billionth of a meter. A single sheet of paper is about 100,000 nanometers thick.

    In the room next door, a focused-ion-beam scanning-electron microscope can look at the sample in even greater detail. It also can drill a hole in a piece of dust from the asteroid by shooting gallium ions at it, like tiny bullets.

    Atoms With Stories to Tell

    “Every atom has something to tell us,” says Zega, walking toward the final destination for the asteroid sample: the transmission electron microscope, or TEM. It’s a towering box of off-white and blue, about 12 feet tall. There’s an innate humor in its size, because a TEM is the only machine in the world that can see something as tiny as an individual atom.

    The TEM, purchased from Hitachi High Technologies in 2016, was shipped by boat from Japan months ago. A team of engineers from the company’s headquarters outside of Tokyo have been here since November, installing and calibrating the microscope. They are expected to head home in June.

    “Looking at microstructures is useful for figuring out origins,” Zega explains.

    Which atoms of an element are next to, or layered on top of, which other atoms is critically important when you want to determine how something formed.

    In the best-case scenario, analyzing the asteroid dirt means “we rewrite the textbooks on our understanding of the origins of our solar system,” Zega says. “I think that’s the neatest thing about a mission like this. It can be full of surprises.

    “Scientist or not, we all look to the stars and ask ‘How?’ and ‘Why?’ We wonder how it all came to be,” he says. “The work that we do here at the University of Arizona contributes to answering those questions.”

    TEM and FIB analyses are carried out at the University of Arizona Kuiper Core Imaging and Characterization Facility supported in part by NSF Grant 1531243 and NASA Grants NNX15AJ22G and NNX12AL47G.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    U Arizona campus

    The University of Arizona (UA) is a place without limits-where teaching, research, service and innovation merge to improve lives in Arizona and beyond. We aren’t afraid to ask big questions, and find even better answers.

    In 1885, establishing Arizona’s first university in the middle of the Sonoran Desert was a bold move. But our founders were fearless, and we have never lost that spirit. To this day, we’re revolutionizing the fields of space sciences, optics, biosciences, medicine, arts and humanities, business, technology transfer and many others. Since it was founded, the UA has grown to cover more than 380 acres in central Tucson, a rich breeding ground for discovery.

    Where else in the world can you find an astronomical observatory mirror lab under a football stadium? An entire ecosystem under a glass dome? Visit our campus, just once, and you’ll quickly understand why the UA is a university unlike any other.

     
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