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  • richardmitnick 1:21 pm on December 16, 2018 Permalink | Reply
    Tags: Huge previously-undetected coral reef off US East Coast, , The Conversation   

    From The Conversation: “Deepwater corals thrive at the bottom of the ocean, but can’t escape human impacts” 

    Conversation
    From The Conversation

    December 3, 2018
    Sandra Brooke

    When people think of coral reefs, they typically picture warm, clear waters with brightly colored corals and fishes. But other corals live in deep, dark, cold waters, often far from shore in remote locations. These varieties are just as ecologically important as their shallow water counterparts. They also are just as vulnerable to human activities like fishing and energy production.

    7
    Deep sea corals off Florida. Image via NOAA.

    Earlier this year I was part of a research expedition conducted by the Deep Search project, which is studying little-known deep-sea ecosystems off the southeast U.S. coast. We were exploring areas that had been mapped and surveyed by the U.S. National Oceanic and Atmospheric Administration’s research ship Okeanos.

    1
    Map of target areas to be surveyed during the first phase of the Deepwater Atlantic Habitats II study, DEEP SEARCH, including seep targets. USGS image.

    2
    NOAA Ship Okeanos Explorer

    NOAA Ship Okeanos Explorer is the only federal vessel dedicated to exploring our largely unknown ocean for the purpose of discovery and the advancement of knowledge about the deep ocean. The ship is operated by the NOAA Commissioned Officer Corps and civilians as part of NOAA’s fleet managed by NOAA’s Office of Marine and Aviation Operations. Mission equipment is operated by NOAA’s Office of Ocean Exploration and Research in partnership with the Global Foundation for Ocean Exploration .

    Missions of the 224-foot vessel include mapping, site characterization, reconnaissance, advancing technology, education, and outreach—all focused on understanding, managing, and protecting our ocean. Expeditions are planned collaboratively, with input from partners and stakeholders, and with the goal of providing data that will benefit NOAA, the scientific community, and the public.

    During Okeanos Explorer expeditions, data are collected using a variety of advanced technologies to explore and characterize unknown or poorly known deepwater ocean areas, features, and phenomena at depths ranging from 250 to 6,000 meters (820 to 19,700 feet). The ship is equipped with four different types of mapping sonars that collect high-resolution data about the seafloor and the water column, a dual-body remotely operated vehicle (ROV) capable of diving to depths of 6,000 meters, and a suite of other instruments to help characterize the deep ocean. Expeditions typically consist of either 24-hour mapping operations or a combination of daytime ROV dives and overnight mapping operations.

    In an area 160 miles off South Carolina we deployed Alvin, a three-person research submersible, to explore some features revealed during the mapping.

    4
    Human Occupied Vehicle (HOV) Alvin is part of the National Deep Submergence Facility (NDSF). Alvin enables in-situ data collection and observation by two scientists to depths reaching 4,500 meters, during dives lasting up to ten hours.

    What the scientists aboard Alvin found was a huge “forest” of coldwater corals. I went down on the second dive in this area and saw another dense coral ecosystem. These were just two features in a series that covered about 85 miles, in water nearly 2,000 feet deep. This unexpected find shows how much we still have to learn about life on the ocean floor.


    Scientists from the August 2018 Deep Search expedition discuss the significance of finding a huge, previously undetected deepwater coral reef off the U.S. East Coast.

    Life in the dark

    Deep corals are found in all of the world’s oceans. They grow in rocky habitats on the seafloor as it slopes down into the deep oceans, on seamounts (underwater mountains), and in submarine canyons. Most are found at depths greater than 650 feet (200 meters), but where surface waters are very cold, they can grow at much shallower depths.

    Shallow corals get much of their energy from sunlight that filters down into the water. Like plants on land, tiny algae that live within the corals’ polyps use sunlight to make energy, which they transfer to the coral polyps. Deep-sea species grow below the sunlit zone, so they feed on organic material and zooplankton, delivered to them by strong currents.

    In both deep and shallow waters, stony corals – which create hard skeletons – are the reef builders, while others such as soft corals add to reef diversity. Just five deep-sea stony coral species create reefs like the one we found in August.

    6
    Stylaster californicus at 135 feet depth on Farnsworth Bank off southern California. NOAA

    The most widely distributed and well-studied is Lophelia pertusa, a branching stony coral that begins life as a tiny larva, settles on hard substrate and grows into a bushy colony.

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    Lophelia pertusa

    As the colony grows, its outside branches block the flow of water that delivers food and oxygen to inner branches and washes away waste. Without flow, the inner branches die and weaken, then break apart, and the outer live branches overgrow the dead skeleton.

    This sequence of growth, death, collapse, and overgrowth continues for thousands of years, creating reefs that can be hundreds of feet tall. These massive, complex structures provide habitat for diverse and abundant assemblages of invertebrates and fishes, some of which are economically valuable.

    Other important types include gorgonians and black corals, often called “tree corals.” These species can grow very large and form dense “coral gardens” in rocky, current-swept areas. Small invertebrates and fishes use their branches for shelter, feeding and nursery habitat.

    Probing the deep oceans

    Organisms that live in deep, cold waters grow slowly, mature late and have long lifespans. Deep-sea black corals are among the oldest animals on earth: One specimen has been dated at 4,265 years old. As they grow, corals incorporate ocean elements into their skeletons. This makes them archives of ocean conditions that long predate human records. They also can provide valuable insights into the likely effects of future changes in the oceans.

    To protect these ecosystems, scientists need to find them. This is challenging because most of the seafloor has not been mapped. Once they have maps, researchers know where to deploy underwater vehicles so they can begin to understand how these ecosystems function.

    Scientists use submersibles like Alvin or remotely operated vehicles to study deep-water corals because other gear, such as trawls and dredges, would become entangled in these fragile colonies and damage them. Submersibles can take visual surveys and collect samples without impacting reefs.

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    The NOAA ROV Deep Discoverer documents benthic communities at Paganini Seamount in the north-central Pacific. NOAA

    This work is expensive and logistically challenging. It requires large ships to transport and launch the submersibles, and can only be done when seas are calm enough to work.

    Looming threats

    The greatest threat to deep corals globally is industrial bottom-trawl fishing, which can devastate deep reefs. Trawling is indiscriminate, sweeping up unwanted animals – including corals – as “bycatch.”“ It also stirs up sediment, which clogs deep-sea organisms’ feeding and breathing structures. Other forms of fishing, including traps, bottom longlines and dredges, can also impact the seafloor.

    Offshore energy production creates other problems. Oil and gas operations can release drilling muds and stir up sediments. Anchors and cables can directly damage reefs, and oil spills can have long-term impacts on coral health. Studies have shown that exposure to oil from the 2010 Deepwater Horizon spill caused stress and tissue damage in Gulf of Mexico deep-sea corals.

    Yet another growing concern is deep sea mining for materials such as cobalt, which is used to build batteries for cell phones and electric cars. The International Seabed Authority, a United Nations agency, is working with scientists and non-government organizations to develop a global regulatory code for deep sea mining, which is expected to be completed in 2020 or 2021. However, the International Union for the Conservation of Nature has warned that not enough is known about deep sea life to ensure that the code will protect it effectively.

    Finally, deep-sea corals are not immune to climate change. Ocean currents circulate around the planet, transporting warm surface waters into the deep sea. Warming temperatures could drive corals deeper, but deep waters are naturally higher in carbon dioxide than surface waters. As their waters become more acidified, deep-sea corals will be restricted to an increasingly narrow band of optimal conditions.

    Conservation and management

    Vast areas of deep coral habitats are on the high seas and are extremely difficult to manage. However, many countries have taken measures to protect deep corals within their territorial waters. For example, the United States has created several deep coral protected areas. And the U.S. Bureau of Ocean Energy Management restricts industry activities near deep corals and funds deep sea coral research.

    These are useful steps, but nations can only protect what they know about. Without exploration, no one would have known about the coral zone that we found off South Carolina, along one of the busiest coastlines in the United States. As a scientist, I believe it is imperative to explore and understand our deep ocean resources so we can preserve them into the future.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 4:04 pm on December 5, 2018 Permalink | Reply
    Tags: , , , , Negative mass particles, The Conversation   

    From The Conversation: “Bizarre ‘dark fluid’ with negative mass could dominate the universe – what my research suggests” 

    Conversation
    From The Conversation

    1
    Bubbles can be modelled as having a negative mass. Mike Lewinski/Flickr, CC BY-ND

    12.5.18
    Jamie Farnes

    It’s embarrassing, but astrophysicists are the first to admit it. Our best theoretical model can only explain 5% of the universe. The remaining 95% is famously made up almost entirely of invisible, unknown material dubbed dark energy and dark matter. So even though there are a billion trillion stars in the observable universe, they are actually extremely rare.

    The two mysterious dark substances can only be inferred from gravitational effects. Dark matter may be an invisible material, but it exerts a gravitational force on surrounding matter that we can measure. Dark energy is a repulsive force that makes the universe expand at an accelerating rate. The two have always been treated as separate phenomena. But my new study, published in Astronomy and Astrophysics, suggests they may both be part of the same strange concept – a single, unified “dark fluid” of negative masses.

    Negative masses are not a new idea in cosmology. Just like normal matter, negative mass particles would become more spread out as the universe expands – meaning that their repulsive force would become weaker over time. However, studies have shown that the force driving the accelerating expansion of the universe is relentlessly constant. This inconsistency has previously led researchers to abandon this idea. If a dark fluid exists, it should not thin out over time.

    In the new study, I propose a modification to Einstein’s theory of general relativity to allow negative masses to not only exist, but to be created continuously. “Matter creation” was already included in an early alternative theory to the Big Bang, known as the Steady State model. The main assumption was that (positive mass) matter was continuously created to replenish material as the universe expands. We now know from observational evidence that this is incorrect. However, that doesn’t mean that negative mass matter can’t be continuously created. I show that this assumed dark fluid is never spread too thinly. Instead it behaves exactly like dark energy.

    It’s embarrassing, but astrophysicists are the first to admit it. Our best theoretical model can only explain 5% of the universe. The remaining 95% is famously made up almost entirely of invisible, unknown material dubbed dark energy and dark matter. So even though there are a billion trillion stars in the observable universe, they are actually extremely rare.

    The two mysterious dark substances can only be inferred from gravitational effects. Dark matter may be an invisible material, but it exerts a gravitational force on surrounding matter that we can measure. Dark energy is a repulsive force that makes the universe expand at an accelerating rate. The two have always been treated as separate phenomena. But my new study, published in Astronomy and Astrophysics, suggests they may both be part of the same strange concept – a single, unified “dark fluid” of negative masses.

    Negative masses are a hypothetical form of matter that would have a type of negative gravity – repelling all other material around them. Unlike familiar positive mass matter, if a negative mass was pushed, it would accelerate towards you rather than away from you.

    Negative masses are not a new idea in cosmology. Just like normal matter, negative mass particles would become more spread out as the universe expands – meaning that their repulsive force would become weaker over time. However, studies have shown that the force driving the accelerating expansion of the universe is relentlessly constant. This inconsistency has previously led researchers to abandon this idea. If a dark fluid exists, it should not thin out over time.

    In the new study, I propose a modification to Einstein’s theory of general relativity to allow negative masses to not only exist, but to be created continuously. “Matter creation” was already included in an early alternative theory to the Big Bang, known as the Steady State model. The main assumption was that (positive mass) matter was continuously created to replenish material as the universe expands. We now know from observational evidence that this is incorrect. However, that doesn’t mean that negative mass matter can’t be continuously created. I show that this assumed dark fluid is never spread too thinly. Instead it behaves exactly like dark energy.

    I also developed a 3D computer model of this hypothetical universe to see if it could also explain the physical nature of dark matter. Dark matter was introduced to explain the fact that galaxies are spinning much faster than our models predict. This implies that some additional invisible matter must be present to prevent them from spinning themselves apart.

    My model shows that the surrounding repulsive force from dark fluid can also hold a galaxy together. The gravity from the positive mass galaxy attracts negative masses from all directions, and as the negative mass fluid comes nearer to the galaxy it in turn exerts a stronger repulsive force onto the galaxy that allows it to spin at higher speeds without flying apart. It therefore appears that a simple minus sign may solve one of the longest standing problems in physics.

    Is the universe really this weird?

    One may argue that this sounds a little far fetched. But while negative masses are bizarre, they are considerably less strange than you may immediately think. For starters, these effects may only seem peculiar and unfamiliar to us, as we reside in a region dominated by positive mass.

    Whether physically real or not, negative masses already have a theoretical role in a vast number of areas. Air bubbles in water can be modelled as having a negative mass. Recent laboratory research has also generated particles that behave exactly as they would if they had negative mass.

    And physicists are already comfortable with the concept of negative energy density. According to quantum mechanics, empty space is made up of a field of fluctuating background energy that can be negative in places – giving rise to waves and virtual particles that pop into and out of existence. This can even create a tiny force that can be measured in the lab.

    The new study could help solve many problems in modern physics. String theory, which is our best hope for unifying the physics of the quantum world with Einstein’s theory of the cosmos, is currently seen as being incompatible with observational evidence. However, string theory does suggest that the energy in empty space must be negative, which corroborates the theoretical expectations for a negative mass dark fluid.

    Moreover, the team behind the groundbreaking discovery of an accelerating universe surprisingly detected evidence for a negative mass cosmology, but took the reasonable precaution of interpreting these controversial findings as “unphysical”.

    The theory could also solve the problem of measuring the universe’s expansion. This is explained by the Hubble-Lemaître Law, the observation that more distant galaxies are moving away at a faster rate. The relationship between the speed and the distance of a galaxy is set by the “Hubble constant”, but measurements of it have continued to vary. This has led to a crisis in cosmology. Fortunately, a negative mass cosmology mathematically predicts that the Hubble “constant” should vary over time. Clearly, there is evidence that this weird and unconventional new theory deserves our scientific attention.

    Where to go from here

    The creator of the field of cosmology, Albert Einstein, did – along with other scientists including Stephen Hawking – consider negative masses. In fact, in 1918 Einstein even wrote that his theory of general relativity may have to be modified to include them.

    Despite these efforts, a negative mass cosmology could be wrong. The theory seems to provide answers to so many currently open questions that scientists will – quite rightly – be rather suspicious. However, it is often the out-of-the-box ideas that provide answers to longstanding problems. The strong accumulating evidence has now grown to the point that we must consider this unusual possibility.

    The largest telescope to ever be built – the Square Kilometre Array (SKA) – will measure the distribution of galaxies throughout the history of the universe. I’m planning to use the SKA to compare its observations to theoretical predictions for both a negative mass cosmology and the standard one – helping to ultimately prove whether negative masses exist in our reality.

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    The Square Kilometre Array may provide answers. SKA Project Development Office and Swinburne Astronomy Productions, CC BY-SA

    What is clear is that this new theory generates a wealth of new questions. So as with all scientific discoveries, the adventure does not end here. In fact, the quest to understand the true nature of this beautiful, unified, and – perhaps polarised – universe has only just begun.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 1:57 pm on December 3, 2018 Permalink | Reply
    Tags: , , The Conversation,   

    From The Conversation: “Scientist at work: To take atomic-scale pictures of tiny crystals, use a huge, kilometer-long synchrotron” 

    Conversation
    From The Conversation

    ANL Advanced Photon Source

    December 3, 2018
    Kerry Rippy

    It’s 4 a.m., and I’ve been up for about 20 hours straight. A loud alarm is blaring, accompanied by red strobe lights flashing. A stern voice announces, “Searching station B. Exit immediately.” It feels like an emergency, but it’s not. In fact, the alarm has already gone off 60 or 70 times today. It is a warning, letting everyone in the vicinity know I’m about to blast a high-powered X-ray beam into a small room full of electronic equipment and plumes of vaporizing liquid nitrogen.

    In the center of this room, which is called station B, I have placed a crystal no thicker than a human hair on the tip of a tiny glass fiber. I have prepared dozens of these crystals, and am attempting to analyze all of them.

    These crystals are made of organic semiconducting materials, which are used to make computer chips, LED lights, smartphone screens and solar panels. I want to find out precisely where each atom inside the crystals is located, how densely packed they are and how they interact with each other. This information will help me predict how well electricity will flow through them.

    To see these atoms and determine their structure, I need the help of a synchrotron, which is a massive scientific instrument containing a kilometer-long loop of electrons zooming around at near the speed of light. I also need a microscope, a gyroscope, liquid nitrogen, a bit of luck, a gifted colleague and a tricycle.

    Getting the crystal in place

    The first step of this experiment involves placing the super-tiny crystals on the tip of the glass fiber. I use a needle to scrape a pile of them together onto a glass slide and put them under a microscope. The crystals are beautiful – colorful and faceted like little gemstones. I often find myself transfixed, staring with sleep-deprived eyes into the microscope, and refocusing my gaze before painstakingly coaxing one onto the tip of a glass fiber.

    Once I’ve gotten the crystal attached to the fiber, I begin the often frustrating task of centering the crystal on the tip of a gyroscope inside station B. This device will spin the crystal around, slowly and continuously, allowing me to get X-ray images of it from all sides.

    1
    On the left is the gyroscope, designed to rotate the crystal through a series of different angles as the X-ray beam hits it. Behind it is the detector panel which records the diffraction spots. On the right is a zoomed in picture of a single crystal, mounted on a glass fiber attached to the tip of the gyroscope. Kerry Rippy, CC BY-ND

    As it spins, liquid nitrogen vapor is used to cool it down: Even at room temperature, atoms vibrate back and forth, making it hard to get clear images of them. Cooling the crystal to minus 196 degrees Celsius, the temperature of liquid nitrogen, makes the atoms stop moving so much.

    X-ray photography

    Once I have the crystal centered and cooled, I close off station B, and from a computer control hub outside of it, blast the sample with X-rays. The resulting image, called a diffraction pattern, is displayed as bright spots on an orange background.

    2
    This is a diffraction pattern that results when you shoot an X-ray beam at a single crystal. Kerry Rippy, CC BY-ND

    What I am doing is not very different from taking photographs with a camera and a flash. I’m about to send light rays at an object and record how the light bounces off it. But I can’t use visible light to photograph atoms – they’re too small, and the wavelengths of light in the visible part of the spectrum are too big. X-rays have shorter wavelengths, so they will diffract, or bounce off atoms.

    However, unlike with a camera, diffracted X-rays can’t be focused with a simple lens. Instead of a photograph-like image, the data I collect are an unfocused pattern of where the X-rays went after they bounced off the atoms in my crystal. A full set of data about one crystal is made up of these images taken from every angle all around the crystal as the gyroscope spins it.

    Advanced math

    My colleague, Nicholas DeWeerd, sits nearby, analyzing data sets I’ve already collected. He has managed to ignore the blaring alarms and flashing lights for hours, staring at diffraction images on his screen to, in effect, turn the X-ray images from all sides of the crystal into a picture of the atoms inside the crystal itself.

    In years past, this process might have taken years of careful calculations done by hand, but now he uses computer modeling to put all the pieces together. He is our research group’s unofficial expert at this part of the puzzle, and he loves it. “It’s like Christmas!” I hear him mutter, as he flips through twinkling images of diffraction patterns.

    3
    Solving a set of diffraction patterns produces an atomic-level picture of a crystal, showing individual molecules (left) and how they pack together to form a crystalline structure. Kerry Rippy, CC BY-ND

    I smile at the enthusiasm he’s managed to maintain so late into the night, as I fire up the synchotron to get my pictures of the crystal perched in station B. I hold my breath as diffraction patterns from the first few angles pop up on the screen. Not all crystals diffract, even if I’ve set everything up perfectly. Often that’s because each crystal is made up of lots of even smaller crystals stuck together, or crystals containing too many impurities to form a repeating crystalline pattern that we can mathematically solve.

    If this one doesn’t deliver clear images, I’ll have to start over and set up another. Luckily, in this case, the first few images that pop up show bright, clear diffraction spots. I smile and sit back to collect the rest of the data set. Now as the gyroscope whirls and the X-ray beam blasts the sample, I have a few minutes to relax.

    I would drink some coffee to stay alert, but my hands are already shaking from caffeine overload. Instead, I call over to Nick: “I’m gonna take a lap.” I walk over to a group of tricycles sitting nearby. Normally used just to get around the large building containing the synchrotron, I find them equally helpful for a desperate attempt to wake up with some exercise.

    As I ride, I think about the crystal mounted on the gyroscope. I’ve spent months synthesizing it, and soon I’ll have a picture of it. With the picture, I’ll gain understanding of whether the modifications that I have made to it, which make it slightly different than other materials I have made in the past, have improved it at all. If I see evidence of better packing or increased intermolecular interactions, that could mean the molecule is a good candidate for testing in electronic devices.

    Exhausted, but happy because I’m collecting useful data, I slowly pedal around the loop, noting that the synchrotron is in high demand. When the beamline is running, it is used 24/7, which is why I’m working through the night. I was lucky to get a time slot at all. At other stations, other researchers like me are working late into the night.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 2:08 pm on October 6, 2018 Permalink | Reply
    Tags: , , Female physics laureate No. 3, Good news at the start of the pipeline, Implicit biases about who does science, Is the number of women in STEM jobs increasing?, The Conversation, What’s not working for women, Why more women don’t win science Nobels,   

    From The Conversation: Women in STEM-“Why more women don’t win science Nobels” 

    Conversation
    From The Conversation

    October 5, 2018
    Mary K. Feeney

    1
    Only 3 percent of these prizes have gone to women since 1901. Reuters/Pawel Kopczynski

    One of the 2018 Nobel Prizes in physics went to Donna Strickland, a major accomplishment for any scientist. Yet much of the news coverage has focused on the fact that she’s only the third female physicist to receive the award, after Marie Curie in 1903 and Maria Goeppert-Mayer 60 years later.

    Though biochemical engineer Frances Arnold also won this year, for chemistry, the rarity of female Nobel laureates raises questions about women’s exclusion from education and careers in science. Female researchers have come a long way over the past century. But there’s overwhelming evidence that women remain underrepresented in the STEM fields of science, technology, engineering and math.

    Studies have shown those who persist in these careers face explicit and implicit barriers to advancement. Bias is most intense in fields that are predominantly male, where women lack a critical mass of representation and are often viewed as tokens or outsiders.

    When women achieve at the highest levels of sports, politics, medicine and science, they serve as role models for all of us, especially for girls and other women. But are things getting better in terms of equal representation? What still holds women back in the classroom, in the lab, in leadership and as award winners?

    Good news at the start of the pipeline

    Traditional stereotypes hold that women “don’t like math” and “aren’t good at science.” Both men and women report these viewpoints, but researchers have empirically disputed them. Studies show that girls and women avoid STEM education not because of cognitive inability, but because of early exposure and experience with STEM, educational policy, cultural context, stereotypes and a lack of exposure to role models.

    For the past several decades, efforts to improve the representation of women in STEM fields have focused on countering these stereotypes with educational reforms and individual programs that can increase the number of girls entering and staying in what’s been called the STEM pipeline – the path from K-12 to college to postgraduate training.

    Is the number of women in STEM jobs increasing?

    Women with college degrees remain underrepresented in science and engineering occupations in the United States, although less so than in the past. Except in computer/mathematical sciences, women have increased their proportion in each broad occupational group since the early 1990s.

    3

    These approaches are working. Women are increasingly likely to express an interest in STEM careers and pursue STEM majors in college. Women now make up half or more of workers in psychology and social sciences and are increasingly represented in the scientific workforce, though computer and mathematical sciences are an exception. According to the American Institute of Physics, women earn about 20 percent of bachelor’s degrees and 18 percent of Ph.D.s in physics, an increase from 1975 when women earned 10 percent of bachelor’s degrees and 5 percent of Ph.D.s in physics.

    More women are graduating with STEM Ph.D.s and earning faculty positions. But they go on to encounter glass cliffs and ceilings as they advance through their academic careers.

    What’s not working for women

    Women face a number of structural and institutional barriers in academic STEM careers.

    In addition to issues related to the gender pay gap, the structure of academic science often makes it difficult for women to get ahead in the workplace and to balance work and life commitments. Bench science can require years of dedicated time in a laboratory. The strictures of the tenure-track process can make maintaining work-life balance, responding to family obligations, and having children or taking family leave difficult, if not impossible.

    Additionally, working in male-dominated workplaces can leave women feeling isolated, perceived as tokens and susceptible to harassment. Women often are excluded from networking opportunities and social events and left to feel they’re outside the culture of the lab, the academic department and the field.

    When women lack critical mass – of about 15 percent or more – they are less empowered to advocate for themselves and more likely to be perceived as a minority group and an exception. When in this minority position, women are more likely to be pressured to take on extra service as tokens on committees or mentors to female graduate students.

    With fewer female colleagues, women are less likely to build relationships with female collaborators and support and advice networks. This isolation can be exacerbated when women are unable to participate in work events or attend conferences because of family or child care responsibilities and an inability to use research funds to reimburse child care.

    Universities, professional associations, and federal funders have worked to address a variety of these structural barriers. Efforts include creating family-friendly policies, increasing transparency in salary reporting, enforcing Title IX protections, providing mentoring and support programs for women scientists, protecting research time for women scientists, and targeting women for hiring, research support and advancement. These programs have mixed results. For example, research indicates that family-friendly policies such as leave and onsite child care can exacerbate gender inequity, resulting in increased research productivity for men and increased teaching and service obligations for women.

    Implicit biases about who does science

    All of us – the general public, the media, university employees, students and professors – have ideas of what a scientist and a Nobel Prize winner looks like. That image is predominantly male, white and older – which makes sense given 97 percent of the science Nobel Prize winners have been men.

    This is an example of an implicit bias: one of the unconscious, involuntary, natural, unavoidable assumptions that all of us, men and women, form about the world around us. People make decisions based on subconscious assumptions, preferences and stereotypes – sometimes even when they are counter to their explicitly held beliefs.

    Research shows that an implicit bias against women as experts and academic scientists is pervasive. It manifests itself by valuing, acknowledging and rewarding men’s scholarship over women’s scholarship. Implicit bias can work against women’s hiring, advancement and recognition of their work. For instance, women seeking academic jobs are more likely to be viewed and judged based on personal information and physical appearance. Letters of recommendation for women are more likely to raise doubts and use language that results in negative career outcomes.

    Implicit bias can affect women’s ability to publish research findings and gain recognition for that work. Men cite their own papers 56 percent more than women do. Known as the “Matilda Effect,” there is a gender gap in recognition, award winning and citations. Women’s research is less likely to be cited by others and their ideas are more likely to be attributed to men. Women’s solo-authored research takes twice as long to move through the review process. Women are underrepresented in journal editorships, as senior scholars and lead authors, and as peer reviewers. This marginalization in research gatekeeping positions works against the promotion of women’s research.

    When a woman becomes a world-class scientist, implicit bias works against the likelihood that she will be invited as a keynote or guest speaker to share her research findings, thus lowering her visibility in the field and the likelihood that she will be nominated for awards. This gender imbalance is notable in how infrequently women experts are quoted in news stories on most topics.

    Women scientists are afforded less of the respect and recognition that should come with their accomplishments. Research shows that when people talk about male scientists and experts, they’re more likely to use their surnames and more likely to refer to women by their first names. Why does this matter? Because experiments show that individuals referred to by their surnames are more likely to be viewed as famous and eminent. In fact, one study found that calling scientists by their last names led people to consider them 14 percent more deserving of a National Science Foundation career award.

    4
    Donna Strickland outside her lab at the University of Waterloo. Reuters/Peter Power

    Female physics laureate No. 3

    Strickland winning a Nobel Prize as an associate professor in physics is a major accomplishment; doing so as a woman who has almost certainly faced more barriers than her male counterparts is, in my view, monumental.

    When asked what it felt like to be the third female Nobel laureate in physics, Strickland noted that at first it was surprising to realize so few women had won the award: “But, I mean, I do live in a world of mostly men, so seeing mostly men doesn’t really ever surprise me either.”

    Seeing mostly men has been the history of science. Addressing structural and implicit bias in STEM will hopefully prevent another half-century wait before the next woman is acknowledged with a Nobel Prize for her contribution to physics. I look forward to the day when a woman receiving the most prestigious award in science is newsworthy only for her science and not her gender.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 11:59 am on September 8, 2018 Permalink | Reply
    Tags: , , , , , , Ten years of Large Hadron Collider discoveries are just the start of decoding the universe, The Conversation   

    From The Conversation: “Ten years of Large Hadron Collider discoveries are just the start of decoding the universe” 

    Conversation
    From The Conversation


    The activity during a high-energy collision at the CMS control room of the European Organization for Nuclear Research, CERN, at their headquarters outside Geneva, Switzerland. AP Photo

    “Ten years! Ten years since the start of operations for the Large Hadron Collider (LHC), one of the most complex machines ever created. The LHC is the world’s largest particle accelerator, buried 100 meters under the French and Swiss countryside with a 17-mile circumference.

    LHC

    CERN map


    CERN LHC Tunnel

    CERN LHC particles

    On Sept. 10, 2008, protons, the center of a hydrogen atom, were circulated around the LHC accelerator for the first time. However, the excitement was short-lived because on Sept. 22 an incident occurred that damaged more than 50 of the LHC’s more than 6,000 magnets – which are critical for keeping the protons traveling on their circular path. Repairs took more than a year, but in March 2010 the LHC began colliding protons. The LHC is the crown jewel of CERN, the European particle physics laboratory that was founded after World War II as a way to reunite and rebuild science in war-torn Europe. Now scientists from six continents and 100 countries conduct experiments there.

    You might be wondering what the LHC does and why it is a big deal. Great questions. The LHC collides two beams of protons together at the highest energies ever achieved in a laboratory. Six experiments located around the 17-mile ring study the results of these collisions with massive detectors built in underground caverns. That’s the what, but why? The goal is to understand the nature of the most basic building blocks of universe and how they interact with each other. This is fundamental science at its most basic.

    3
    View of the LHC in its tunnel at CERN (European particle physics laboratory) near Geneva, Switzerland. The LHC is a 27-kilometer-long underground ring of superconducting magnets housed in this pipe-like structure, or cryostat. The cryostat is cooled by liquid helium to keep it at an operating temperature just above absolute zero. It will accelerate two counterrotating beam of protons to an energy of 7 tera-electron volts (TeV) and then bring them to collide head-on. Several detectors are being built around the LHC to detect the various particles produced by the collision. Martial Trezzini/KEYSTONE/AP Photo.

    The LHC has not disappointed. One of the discoveries made with the LHC includes the long sought-after Higgs boson, which gives mass to all of the protons and neutrons in the quark gluon plasma, predicted in 1964 by scientists working to combine theories of two of the fundamental forces of nature.

    CERN CMS Higgs Event


    CERN ATLAS Higgs Event

    I work on one of the six LHC experiments – the Compact Muon Solenoid experiment designed to discover the Higgs boson and search for signs of previously unknown particles or forces.

    CERN/CMS Detector

    My institution, Florida State University, joined the Compact Muon Solenoid collaboration in 1994 when I was a young graduate student at another school working on a different experiment at a different laboratory. Planning for the LHC dates back to 1984. The LHC was hard to build and expensive – 10 billion euros – and took 24 years to come to fruition. Now we are celebrating 10 years since the LHC began operating.

    Discoveries from the LHC

    The most significant discovery to come from the LHC so far is the discovery of the Higgs boson on July 4, 2012. The announcement was made at CERN and captivated a worldwide audience. In fact, my wife and I watched it via webcast on our big screen TV in our living room. Since the announcement was at 3 a.m. Florida time, we went for pancakes at IHOP to celebrate afterwards.

    The Higgs boson was the last remaining piece of what we call the standard model of particle physics.

    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.


    Standard Model of Particle Physics from Symmetry Magazine

    This theory covers all of the known fundamental particles – 17 of them – and three of the four forces through which they interact, although gravity is not yet included. The standard model is an incredibly well-tested theory. Two of the six scientists who developed the part of the standard model that predicts the Higgs boson won the Nobel Prize in 2013.

    3
    The Higgs boson, sometimes refered to as the ‘God particle,’ was first seen during by experiments at the Large Hadron Collider. Designua/Shutterstock.com

    I am often asked, why do we continue to run experiments, smashing together protons, if we’ve already discovered the Higgs boson? Aren’t we done? Well, there is still lots to be understood. There are a number of questions that the standard model does not answer. For example, studies of galaxies and other large-scale structures in the universe indicate that there is a lot more matter out there than we observe. We call this dark matter since we can’t see it. The most common explanation to date is that dark matter is made of an unknown particle. Physicists hope that the LHC may be able to produce this mystery particle and study it. That would be an amazing discovery.

    Just last week, the ATLAS and Compact Muon Solenoid collaborations announced the first observation of the Higgs boson decaying, or breaking apart, into bottom quarks. The Higgs boson decays in many different ways – some rare, some common. The standard model makes predictions about how often each type of decay happens. To fully test the model, we need to observe all of the predicted decays. Our recent observation is in agreement with the standard model – another success.

    More questions, more answers to come

    There are lots of other puzzles in the universe and we may require new theories of physics to explain such phenomena – such as matter/anti-matter asymmetry to explain why the universe has more matter than anti-matter, or the hierarchy problem to understand why gravity is so much weaker than the other forces.

    But for me, the quest for new, unexplained data is important because every time that physicists think we have it all figured out, nature provides a surprise that leads to a deeper understanding of our world.

    The LHC continues to test the standard model of particle physics. Scientists love when theory matches data. But we usually learn more when they don’t. This means we don’t fully understand what is happening. And that, for many of us, is the future goal of the LHC: to discover evidence of something we don’t understand. There are thousands of theories that predict new physics that we have not observed. Which are right? We need a discovery to learn if any are correct.

    CERN plans to continue LHC operations for a long time. We are planning upgrades to the accelerator and detectors to allow it to run through 2035.

    It is not clear who will retire first, me or the LHC. Ten years ago, we anxiously awaited the first beams of protons. Now we are busy studying a wealth of data and hope for a surprise that leads us down a new path. Here’s to looking forward to the next 20 years.”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 6:19 am on August 24, 2018 Permalink | Reply
    Tags: , , , , , , The Conversation   

    From The Conversation: “We’re going to get a better detector: time for upgrades in the search for gravitational waves” 

    Conversation
    From The Conversation

    August 16, 2018
    Robert Ward

    It’s been a year since ripples in space-time from a colliding pair of dead stars tickled the gravitational wave detectors of the Advanced LIGO and Advanced Virgo facilities.


    Soon after, astronomers around the world began a campaign to observe the afterglow of the collision of a binary neutron star merger in radio waves, microwaves, visible light, x-rays and more.

    See https://sciencesprings.wordpress.com/2017/10/16/from-ucsc-a-uc-santa-cruz-special-report-neutron-stars-gravitational-waves-and-all-the-gold-in-the-universe/

    This was the dawn of multi-messenger astronomy: a new era in astronomy, where events in the universe are observed with more than just a single type of radiation. In this case, the messengers were gravitational waves and electromagnetic radiation.

    What we’ve learned (so far)

    From this single event, we learned an incredible amount. Last October, on the day the detection was made public, 84 scientific papers were published (or the preprints made available).

    We learned that gravity and light travel at the same speed, neutron star mergers are a source of short gamma-ray bursts, and that kilonovae – the explosion from a neutron star merger – are where our gold comes from.

    This rich science came from the fact that we were able to combine our observatories to witness this single event from multiple astronomical “windows”. The gravitational waves arrived first, followed 1.7 seconds later by gamma-rays. That is a pretty small delay, considering the waves had been travelling for 130 million years.

    Over the next few weeks, visible light and radio waves began to be observed and then slowly faded.

    It seemed like the news about gravitational waves was coming fast and furious, with the first detection announced in 2016, a Nobel prize in 2017, and the announcement of the binary neutron star merger just weeks after the Nobel prize.

    Time for upgrades

    On this first anniversary of the neutron star merger, the gravitational wave detectors are offline for upgrades. They actually went offline shortly after the detection and will come back online some time early in 2019.

    The work of making gravitational wave detectors function requires extraordinary patience and dedication. These are exquisite experiments – it took more than 40 years of technological development by a community of more than a thousand scientists to get to the point of detecting the first signal.

    Naturally, improving on this work is not easy. So what does it actually take?

    We really do listen to gravitational waves, and our detectors act more like microphones than telescopes or cameras.

    Quiet please!

    To detect gravitational waves, we need to do more than just turn off the dishwasher. We need to build the quietest, best-isolated thing on Earth.

    Unfortunately, the laws of quantum mechanics and thermodynamics both prevent us from eliminating the noise entirely. Nonetheless, we strive to do the best that these fundamental limits permit. This involves, among many other extraordinary things, hanging our mirrors on glass threads .

    2
    Before sealing up the chamber and pumping the vacuum system down, a LIGO optics technician inspects one of LIGO’s core optics (mirrors) by illuminating its surface with light at a glancing angle. Matt Heintze/Caltech/MIT/LIGO Lab

    Our mirrors weight 40kg each and are suspended from four of these glass threads, which are less than a half-millimetre in diameter and exquisitely crafted.

    The threads are under enormous stress, and the slightest imperfection (or the slightest touch) can cause them to explode.

    Just such an explosion happened earlier this year while installing a new mirror. Fortunately, the precious mirror fell into a cradle designed for just such a possibility, and was not damaged.

    Nonetheless, the delicate, intricate work of creating the glass threads, attaching them to the mirror, hanging the mirror and then installing it all needed to be redone.

    Improvements to the detector

    This was a heartbreaking setback for the team, but the added delay was not entirely in vain. In parallel with remaking the glass threads and rehanging the new mirror, we made some other improvements to the detector, for which we otherwise would not have had enough time.

    One of the goals of this upgrade period is to install something called a quantum squeezed light source into the gravitational wave detectors.

    As mentioned earlier, quantum mechanics mandates a certain minimum amount of noise in any measurement. We can’t arbitrarily reduce this quantum noise, but we can move it around and change its shape by squeezing it.

    This is a bit like sweeping dust under the rug. It’s not really gone, but it might not bother you so much anymore. The quantum squeezed light source does just this.

    3
    Australian National University scientists Nutsinee Kijbunchoo and Terry McCrae build components for a quantum squeezed light source at LIGO Hanford Observatory in Washington, US. Nutsinee Kijbunchoo

    A gravitational wave detector is already a very complex system, and a squeezed light source is another complex system, so putting them together can be a challenge.

    Despite the complexity of this challenge, when the squeezed light source was activated for the first time at the LIGO detector in Livingston, Louisiana, US, in February this year there was an immediate improvement in the quantum noise: the gravitational wave detector output got just a bit quieter.

    ESA/NASA eLISA space based, the future of gravitational wave research

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 12:08 pm on August 21, 2018 Permalink | Reply
    Tags: , , , , deaths and collisions of stars through 1 million snapshots in UV, , Swift’s telescope reveals birth, The Conversation   

    From The Conversation: “Swift’s telescope reveals birth, deaths and collisions of stars through 1 million snapshots in UV” 

    Conversation
    From The Conversation

    1

    Imagine if the color camera had never been invented and all our images were in black and white. The world would still look beautiful, but incomplete. For thousands of years, that was how humans saw the universe. On Earth, we can only see part of the light that stars emit.

    Much of what we can’t see – in the infrared, the ultraviolet, the X-ray and the gamma ray wavelengths – is blocked by the Earth’s atmosphere. For the most part, this is a good thing. The atmosphere traps infrared light keeping the Earth warm at night and blocks high-energy ultraviolet light, X-rays and gamma rays, keeping us safe from deadly cosmic radiation, while letting in visible portions of the spectrum of light. For astronomers, however, this has a drawback: We look at the universe with one eye shut, unable to receive all of the information the universe is sending to us.

    2
    Visible light is just a tiny part of the electromagnetic spectrum. NASA

    Launched on November 20, 2004, and orbiting an altitude of 340 miles, NASA’s Neil Gehrels Swift Observatory has three telescopes that monitor the universe using wavelengths of light that are blocked by Earth’s atmosphere.

    NASA Neil Gehrels Swift Observatory

    These included the X-Ray Telescope, the gamma-ray-sensitive Burst-Alert Telescope and the Ultraviolet Optical Telescope (UVOT). The UVOT recently delivered its 1 millionth image – data that astrophysicists like me use to gain insights into everything from the origins of the universe to the chemical composition of nearby comets.

    Watching the birth of black holes

    Swift’s primary mission is to study the afterglow of gamma ray bursts (GRBs) – which document the birth of black holes. Black holes are forged in the most violent explosions in the universe – the explosion of a massive star or the merging of two neutron stars (the shriveled husks left over from past stellar explosions). These explosions are so powerful – producing tens to hundreds of billions of times more energy than the sun – that even though they occur billions of light years away from Earth, they can still be detected by instruments like Swift. In fact, the first GRBs were detected by the Vela satellites, which were built to detect the explosions of nuclear weapons.

    Over nearly 14 years, Swift has studied over a thousand GRBs. In doing so, it has revealed what powers them and given us glimpses into the furthest reaches of the cosmos, to the time when the first stars were being formed after the Big Bang.

    However, one of the things you learn working on a space telescope mission is that if you build it, they will come. The mission provides capabilities to the community of astrophysicists – simultaneous X-ray/UV imaging and a rapid response to requests to observe and photograph specific sections of the sky – which are only available to Swift. We can focus our telescopes on an object of interest within hours of a “Target of Opportunity” request through our website, something no other mission can do. UVOT also fills an important niche by observing larger areas of the sky than can be observed with the more powerful UV instruments aboard the Hubble Space Telescope. These capabilities have proved a boon to the community and enabled study all sorts of objects and phenomenon beyond GRBs.

    Swift’s ultraviolet-aided discoveries

    Nearby galaxies are full of activity with new stars being formed. Swift is able to capture panoramic ultraviolet images that highlight the youngest, most massive stars in these galaxies. This gives us insight into what the universe has been doing over the last few hundred million years. My research team’s work has focused on nearby galaxies – like Andromeda and the Magellanic Clouds – to reveal what processes drive their past and ongoing star formation.

    Andromeda Galaxy Messier 31 with Messier32 -a satellite galaxy copyright Terry Hancock.

    Magellanic Clouds ESO S. Brunier

    With UVOT, we get a much better view of supernova explosions. These can occur when a white dwarf, the remnant of a star like the sun, explodes, or during the final death throes of a massive star, more than eight times the mass of the sun. These events generate enormous amounts of ultraviolet light, and Swift has a unique ability to observe them within hours of discovery.

    3
    On the left is an ultraviolet composite made from several images of the Whirpool Galaxy (M51) taken between 2005-2007. The image on the right was made in June 2011, shortly after astronomers detected the explosion of a massive star in one of the galaxy’s outer spiral arms. The object is marked by the red circle. NASA/Swift/E. Hoversten, PSU, CC BY-ND

    Comets sweep through our solar system, transforming from a frozen solid ball to a vapor as they approach the sun and creating magnificent tails of ionized particles. Swift studies these comets, and analyzes their chemical composition by breaking the light they emit into different wavelengths. Swift also allows scientists to measure a comet’s rotation by seeing how the light changes over time. This has revealed that violent eruptions on the comet surface can dramatically alter a comet’s path.

    5
    This image of Comet Lulin was taken by Swift on January 28, 2009. It shows data obtained by Swift’s Ultraviolet/Optical Telescope (blue and green) and X-Ray Telescope (red). The image of the star field (white) was acquired by the Digital Sky Survey. At the time of the observation, comet Lulin was 99.5 million miles from Earth and 115.3 million miles from the sun. The ultraviolet light comes from hydroxyl molecules and shows that, at this time, Lulin was shedding 800 gallons of water every second. D. Bodewits/Swift/NASA, CC BY-ND

    One of the most exciting discoveries that Swift made was connected with the recent discovery of gravitational waves by the Laser Interferometer Gravitational-Wave Observatory (LIGO).


    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    Caltech/MIT Advanced aLigo Hanford, WA, USA installation


    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project

    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger-Zib

    ESA/eLISA the future of gravitational wave research

    1
    Skymap showing how adding Virgo to LIGO helps in reducing the size of the source-likely region in the sky. (Credit: Giuseppe Greco (Virgo Urbino group)

    Gravitational waves are distortions in the fabric of spacetime created by the motions of extremely massive objects. In August of 2017, two neutrons stars collided in a distant galaxy, creating gravitational waves powerful enough to be detected on Earth. Swift was one of an army of telescopes that looked for the source of the gravitational waves. The mad scramble over those few days led to one of the most exciting discoveries of the last decade – a luminous afterglow from the source of the gravitational waves. This has opened up new branches of science by connecting a new way of studying the universe – through gravitational waves – to the traditional way – through light.

    See also https://sciencesprings.wordpress.com/2017/10/16/from-ucsc-a-uc-santa-cruz-special-report-neutron-stars-gravitational-waves-and-all-the-gold-in-the-universe/

    UVOT has been taking snapshots of the universe since 2004 and finally piled up its millionth image. Its success is a testament to the international team of engineers, scientists and staff at the three institutions that support it – the Pennsylvania State University; Mullard Space Science Laboratory in Surrey, England; and NASA’s Goddard Space Flight Center in Greenbelt, Maryland. It has been my privilege to be a part of this team for the last nine years. What does the future hold for UVOT? We hope to find more sources of gravitational waves, survey nearby galaxies, study even more supernovae, and monitor how objects in the universe change over time.

    Here’s to the next million images.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 9:43 am on August 21, 2018 Permalink | Reply
    Tags: , , , , , The Conversation   

    From The Conversation and EarthSky: “What are rare earths, crucial elements in modern technology? 4 questions answered” 

    1

    EarthSky

    Conversation
    From The Conversation

    August 16, 2018
    Stanley Mertzman

    1
    A handful of europium. Image via Alchemist-hp

    Most Americans use rare earth elements every day – without knowing it, or knowing anything about what they do. That could change, as these unusual materials are becoming a focal point in the escalating trade war between the U.S. and China.

    1. What are rare earth elements?

    Strictly speaking, they are elements like others on the periodic table – such as carbon, hydrogen and oxygen – with atomic numbers 57 to 71. There are two others with similar properties that are sometimes grouped with them, but the main rare earth elements are those 15. To make the first one, lanthanum, start with a barium atom and add one proton and one electron. Each successive rare earth element adds one more proton and one more electron.

    2
    An electron diagram of a barium element, the last element before the lanthanide rare earth elements. Greg Robson and Pumbaa, CC BY-SA

    3
    An electron diagram of a lanthanum atom, with one more electron in its fifth orbital than barium. Greg Robson and Pumbaa, CC BY-SA

    4
    Cerium has one more electron in its fifth orbital and one more in its fourth than barium. Greg Robson and Pumbaa, CC BY-SA

    It’s significant that there are 15 rare earth elements: Chemistry students may recall that when electrons are added to an atom, they collect in groups or layers, called orbitals, which are like concentric circles of a target around the bull’s-eye of the nucleus.

    The innermost target circle of any atom can contain two electrons; adding a third electron means adding one in the second target circle. That’s where the next seven electrons go, too – after which electrons must go to the third target circle, which can hold 18. The next 18 electrons go into the fourth target circle.

    Then things start to get a bit odd. Though there is still room for electrons in the fourth target circle, the next eight electrons go into the fifth target circle. And despite more room in the fifth, the next two electrons after that go into the sixth target circle.

    That’s when the atom becomes barium, atomic number 56, and those empty spaces in earlier target circles start to fill. Adding one more electron – to make lanthanum, the first in the series of rare earth elements – puts that electron in the fifth circle. Adding another, to make cerium, atomic number 58, adds an electron to the fourth circle. Making the next element, praseodymium, actually moves the newest electron in the fifth circle to the fourth, and adds one more. From there, additional electrons fill up the fourth circle.

    In all elements, the electrons in the outermost circle largely influence the element’s chemical properties. Because the rare earths have identical outermost electron configurations, their properties are quite similar.

    2. Are rare earth elements really rare?

    No. They’re much more abundant in the Earth’s crust than many other valuable elements. Even the rarest rare earth, thulium, with atomic number 69, is 125 times more common than gold. And the least-rare rare earth, cerium, with atomic number 58, is 15,000 times more abundant than gold.

    5
    The rarest rare earth element, thulium. Jurii, CC BY

    They are rare in one sense, though – mineralogists would call them “dispersed,” meaning they’re mostly sprinkled across the planet in relatively low concentrations. Rare earths are often found in rare igneous rocks called carbonatites – nothing so common as basalt from Hawaii or Iceland, or andesite from Mount St. Helens or Guatemala’s Volcano Fuego.

    There are a few regions that are have lots of rare earths – and they’re mostly in China, which produces more than 80 percent of the global annual total of 130,000 metric tons. Australia has a few areas too, as do some other countries. The U.S. has a little bit of area with lots of rare earths, but the last American source for them, California’s Mountain Pass Quarry, closed in 2015.

    3. If they’re not rare, are they very expensive?

    Yes, quite. In 2018, the cost for an oxide of neodymium, atomic number 60, is US$107,000 per metric ton. The price is expected to climb to $150,000 by 2025.

    Europium is even more costly – about $712,000 per metric ton.

    Part of the reason is that rare earth elements can be chemically difficult to separate from each other to get a pure substance.

    4. What are rare earth elements useful for?

    In the last half of the 20th century, europium, with atomic number 63, came in to wide demand for its role as a color-producing phosphor in video screens, including computer monitors and plasma
    TVs. It’s also useful for absorbing neutrons in nuclear reactors’ control rods.

    6
    A cube of small neodymium magnets. XRDoDRX, CC BY-SA

    Other rare earths are also commonly used in electronic devices today. Neodymium, atomic number 60, for instance, is a powerful magnet, useful in smartphones, televisions, lasers, rechargeable batteries and hard drives. An upcoming version of Tesla’s electric car motor is also expected to use neodymium.

    Demand for rare earths has risen steadily since the middle of the 20th century, and there are no real alternative materials to replace them. As important as rare earths are to a modern technology-based society, and as difficult as they are to mine and use, the tariff battle may put the U.S. in a very bad place, turning both the country and rare earth elements themselves into pawns in this game of economic chess.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

    Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. “Being an EarthSky editor is like hosting a big global party for cool nature-lovers,” she says.

     
  • richardmitnick 9:59 am on June 11, 2018 Permalink | Reply
    Tags: , , , , How we discovered 840 minor planets beyond Neptune – and what they can tell us, , The Conversation   

    From Queens University, Belfast via The Conversation: “How we discovered 840 minor planets beyond Neptune – and what they can tell us” 

    Queens University, Belfast

    The Conversation

    May 25, 2018
    Michele Bannister

    Our solar system is a tiny but wonderfully familiar corner of the vast, dark universe – we have even been able to land spacecraft on our celestial neighbours. Yet its outer reaches are still remarkably unmapped. Now we have discovered 840 small worlds in the distant and hard-to-explore region beyond Neptune. This is the largest set of discoveries ever made, increasing the number of distant objects with well known paths around the sun by 50%.

    These little icy worlds are important as they help us tell the solar system’s history. They can also help us test the idea that there’s a yet unseen planet lurking in the outer solar system.

    Our planetary system as we see it today is not as it formed. When the sun was newborn, it was surrounded by a massive disk of material. Encounters with tiny, growing planets – including some of the worlds we’ve just discovered – moved the giant planets outward from the sun until they settled into their present locations. The growing planets, on the other hand, went everywhere, scattering both inward and outward.

    Planetary migration also happened in far away systems around many other stars. Fortunately, the celestial bodies in our own planetary system are comparatively close by, making it the only place where we can see the intricate details of how migration happened. Mapping the minor planet populations that are left over from the disk lets us reconstruct the history of how the big planets were pushed into place.

    Mapping the sky

    The new discoveries were made as part of a five year project called the Outer Solar System Origins Survey (OSSOS). The observations, conducted in 2013-2017, used the [MegaCam] imaging camera of one of the world’s major telescopes – the Canada-France-Hawaii Telescope on Maunakea in Hawaii.



    CFHT Telescope, Maunakea, Hawaii, USA, at Maunakea, Hawaii, USA,4,207 m (13,802 ft) above sea level


    CFHT MegaCam

    The survey looked for faint, slow-moving points of light within eight big patches of sky near the plane of the planets and away from the dense star fields of the Milky Way.

    With 840 discoveries made at distances between six and 83 astronomical units (au) – one such unit is the distance between the sun and the Earth – the survey gives us a very good overview of the many sorts of orbits these “trans-Neptunian objects” have.

    Earlier surveys have suffered from losing some of their distant discoveries – when too few observations occur, the predicted path of a minor planet in the sky will be so uncertain that a telescope can’t spot it again, and it is considered “lost”. This happens more to objects with highly tilted and elongated orbits, producing a bias in what’s currently known about these populations.

    Our new survey successfully tracked all its distant discoveries. The frequent snapshots we made of the 840 objects over several years meant that each little world’s orbit could be determined very precisely. In total, more than 37,000 hand-checked measurements of the hundreds of discoveries precisely pinned down their arcs across the sky.

    We also created an accompanying software “simulator” (a computer model), which provides a powerful tool for testing the inventory and history of our solar system. This lets theorists test out their models of how the solar system came to be in the shape we see it today, comparing them with our real discoveries.

    Strange new worlds

    The new icy and rocky objects fall into two main groups. One includes those that reside on roundish orbits in the Kuiper belt, which extends from 37au to approximately 50au from the sun.

    Kuiper Belt. Minor Planet Center

    The other consists of worlds that orbit in a careful dance of avoidance with Neptune as it travels around the sun. These “resonant” trans-Neptunian objects, which include Pluto, were pushed into their current elongated orbits during Neptune’s migration outwards.

    In the Kuiper belt, we found 436 small worlds. Their orbits confirm that a concentrated “kernel” of the population nestles on almost perfectly round, flat orbits at 43 to 45au. These quiet orbits may have been undisturbed since the dawn of the solar system, a leftover fraction of the original disk. Soon, we will see a member of this group up close: the New Horizons spacecraft, which visited Pluto in 2015, will be flying by a world that’s about the size of London on New Year’s Day 2019.

    NASA/New Horizons spacecraft

    3
    The dwarf planet candidate 2015 RR245 is on an exceptionally distant orbit, but is one of the few dwarf planets that could one day be reached by a spacecraft mission. Alex Parker/OSSOS, CC BY-SA

    We found 313 resonant trans-Neptunian objects, with the survey showing that they exist as far out as an incredible 130au – and are far more abundant than previously thought. Among these discoveries is the dwarf planet 2015 RR245, which is about half the size of Britain. It may have hopped onto its current orbit at 82au after an encounter with Neptune hundreds of millions of years ago. It was once among the 90,000 scattered objects of smaller size that we estimate currently exist.

    Are there more planets?

    Among the most unusual of the discoveries are nine little worlds on incredibly distant orbits, never coming closer to the sun than Neptune’s orbit, and taking as long as 20,000 years to travel around our star. Their existence implies an unseen population of hundreds of thousands of trans-Neptunian objects on similar orbits.

    5
    Artist’s concept of Planet Nine. NASA/JPL-Caltech/Robert Hurt, CC BY-SA

    How these objects got on their present paths is unclear — some orbit so far out that, even at their closest approach, they are barely tugged by Neptune’s gravity. One explanation that has been put forward is that a yet unseen large planet, sometimes called “Planet Nine”, could be causing them to cluster in space. However, our nine minor planets all seem to be spread out smoothly, rather than clustering. Perhaps the shepherding of such a large planet is more subtle – or these orbits instead formed in a different way.

    The history of our solar system is just beginning to be told. We hope this new set of discoveries will help piece together the story.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    Queen’s University Belfast (informally Queen’s or QUB) is a public research university in Belfast, Northern Ireland. The university was chartered in 1845, and opened in 1849 as “Queen’s College, Belfast”.

    The university forms the focal point of the Queen’s Quarter area of the city, one of Belfast’s six cultural districts. It offers academic degrees at various levels and across a broad subject range, with over 300 degree programmes available. Its acting President and Vice-Chancellor is James McElnay, and its Chancellor is Thomas Moran. The annual income of the institution for 2016–17 was £337.6 million of which £79.6 million was from research grants and contracts, with an expenditure of £325.1 million.

    Queen’s is a member of the Russell Group of leading research intensive universities, the Association of Commonwealth Universities, the European University Association, Universities Ireland and Universities UK. The university is associated with two Nobel laureates and one Turing Award laureate.

     
  • richardmitnick 3:17 pm on May 14, 2018 Permalink | Reply
    Tags: , , , , , , The Conversation, The next big discovery in astronomy? Scientists probably found it years ago – but they don’t know it yet   

    From The Conversation: “The next big discovery in astronomy? Scientists probably found it years ago – but they don’t know it yet” 

    Conversation
    From The Conversation

    May 14, 2018
    Eileen Meyer

    1
    An artist’s illustration of a black hole “eating” a star. NASA/JPL-Caltech

    Earlier this year, astronomers stumbled upon a fascinating finding: Thousands of black holes likely exist near the center of our galaxy.

    1
    Hundreds — Perhaps Thousands — of Black Holes Occupy the Center of the Milky Way

    The X-ray images that enabled this discovery weren’t from some state-of-the-art new telescope. Nor were they even recently taken – some of the data was collected nearly 20 years ago.

    No, the researchers discovered the black holes by digging through old, long-archived data.

    Discoveries like this will only become more common, as the era of “big data” changes how science is done. Astronomers are gathering an exponentially greater amount of data every day – so much that it will take years to uncover all the hidden signals buried in the archives.

    The evolution of astronomy

    Sixty years ago, the typical astronomer worked largely alone or in a small team. They likely had access to a respectably large ground-based optical telescope at their home institution.

    Their observations were largely confined to optical wavelengths – more or less what the eye can see. That meant they missed signals from a host of astrophysical sources, which can emit non-visible radiation from very low-frequency radio all the way up to high-energy gamma rays. For the most part, if you wanted to do astronomy, you had to be an academic or eccentric rich person with access to a good telescope.

    Old data was stored in the form of photographic plates or published catalogs. But accessing archives from other observatories could be difficult – and it was virtually impossible for amateur astronomers.

    Today, there are observatories that cover the entire electromagnetic spectrum. No longer operated by single institutions, these state-of-the-art observatories are usually launched by space agencies and are often joint efforts involving many countries.

    With the coming of the digital age, almost all data are publicly available shortly after they are obtained. This makes astronomy very democratic – anyone who wants to can reanalyze almost any data set that makes the news. (You too can look at the Chandra data that led to the discovery of thousands of black holes!)

    These observatories generate a staggering amount of data. For example, the Hubble Space Telescope, operating since 1990, has made over 1.3 million observations and transmits around 20 GB of raw data every week, which is impressive for a telescope first designed in the 1970s.

    NASA/ESA Hubble Telescope

    The Atacama Large Millimeter Array in Chile now anticipates adding 2 TB of data to its archives every day.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    Data firehose

    The archives of astronomical data are already impressively large. But things are about to explode.

    Each generation of observatories are usually at least 10 times more sensitive than the previous, either because of improved technology or because the mission is simply larger. Depending on how long a new mission runs, it can detect hundreds of times more astronomical sources than previous missions at that wavelength.

    For example, compare the early EGRET gamma ray observatory, which flew in the 1990s, to NASA’s flagship mission Fermi, which turns 10 this year. EGRET detected only about 190 gamma ray sources in the sky. Fermi has seen over 5,000.

    NASA/Fermi LAT


    NASA/Fermi Gamma Ray Space Telescope

    The Large Synoptic Survey Telescope, an optical telescope currently under construction in Chile, will image the entire sky every few nights. It will be so sensitive that it will generate 10 million alerts per night on new or transient sources, leading to a catalog of over 15 petabytes after 10 years.

    LSST

    LSST Camera, built at SLAC



    LSST telescope, currently under construction on the El Peñón peak at Cerro Pachón Chile, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile, alongside the existing Gemini South and Southern Astrophysical Research Telescopes.

    The Square Kilometre Array , when completed in 2020, will be the most sensitive telescope in the world, capable of detecting airport radar stations of alien civilizations up to 50 light-years away. In just one year of activity, it will generate more data than the entire internet.


    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia


    SKA Murchison Widefield Array, Boolardy station in outback Western Australia, at the Murchison Radio-astronomy Observatory (MRO)


    SKA Meerkat telescope, 90 km outside the small Northern Cape town of Carnarvon, SA


    SKA LOFAR core (“superterp”) near Exloo, Netherlands


    These ambitious projects will test scientists’ ability to handle data. Images will need to be automatically processed – meaning that the data will need to be reduced down to a manageable size or transformed into a finished product. The new observatories are pushing the envelope of computational power, requiring facilities capable of processing hundreds of terabytes per day.

    The resulting archives – all publicly searchable – will contain 1 million times more information that what can be stored on your typical 1 TB backup disk.

    Unlocking new science

    The data deluge will make astronomy become a more collaborative and open science than ever before. Thanks to internet archives, robust learning communities and new outreach initiatives, citizens can now participate in science. For example, with the computer program Einstein@Home, anyone can use their computer’s idle time to help search for gravitational waves from colliding black holes.

    It’s an exciting time for scientists, too. Astronomers like myself often study physical phenomena on timescales so wildly beyond the typical human lifetime that watching them in real-time just isn’t going to happen. Events like a typical galaxy merger – which is exactly what it sounds like – can take hundreds of millions of years. All we can capture is a snapshot, like a single still frame from a video of a car accident.

    However, there are some phenomena that occur on shorter timescales, taking just a few decades, years or even seconds. That’s how scientists discovered those thousands of black holes in the new study. It’s also how they recently realized that the X-ray emission from the center of a nearby dwarf galaxy has been fading since first detected in the 1990s. These new discoveries suggest that more will be found in archival data spanning decades.

    In my own work, I use Hubble archives to make movies of “jets,” high-speed plasma ejected in beams from black holes. I used over 400 raw images spanning 13 years to make a movie of the jet in nearby galaxy M87. That movie showed, for the first time, the twisting motions of the plasma, suggesting that the jet has a helical structure.

    This kind of work was only possible because other observers, for other purposes, just happened to capture images of the source I was interested in, back when I was in kindergarten. As astronomical images become larger, higher resolution and ever more sensitive, this kind of research will become the norm.

    See the full article here .

    Please help promote STEM in your local schools.

    stem

    Stem Education Coalition

    The Conversation US launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
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