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  • richardmitnick 8:13 am on August 17, 2018 Permalink | Reply
    Tags: , , , Carnegie Institution For Science, , hydrogen offers a reflection of giant planet interiors, , Under pressure   

    From Carnegie Institution for Science: “Under pressure, hydrogen offers a reflection of giant planet interiors” 

    Carnegie Institution for Science
    From Carnegie Institution for Science

    1
    Unraveling the properties of fluid metallic hydrogen at the National Ignition Facility could help scientists unlock the mysteries of Jupiter’s formation and internal structure. Credit: Mark Meamber, LLNL.

    National Ignition Facility at LLNL

    August 15, 2018

    Lab-based mimicry allowed an international team of physicists including Carnegie’s Alexander Goncharov to probe hydrogen under the conditions found in the interiors of giant planets—where experts believe it gets squeezed until it becomes a liquid metal, capable of conducting electricity. Their work is published in Science.

    Hydrogen is the most-abundant element in the universe and the simplest—comprised of only a one proton and one electron in each atom. But that simplicity is deceptive, because there is still so much to learn about it, including its behavior under conditions not found on Earth.

    For example, although hydrogen on the surface of giant planets, like our Solar System’s Jupiter and Saturn, is a gas, just like it is on our own planet, deep inside these giant planetary interiors, scientists believe it becomes a metallic liquid.

    “This transformation has been a longstanding focus of attention in physics and planetary science,” said lead author Peter Celliers of Lawrence Livermore National Laboratory.

    The research team—which also included scientists from the French Alternative Energies and Atomic Energy Commission, University of Edinburgh, University of Rochester, University of California Berkeley, and George Washington University—focused on this gas-to-metallic-liquid transition in molecular hydrogen’s heavier isotope deuterium. (Isotopes are atoms of the same element that have the same number of protons but a different number of neutrons.)

    They studied how deuterium’s ability to absorb or reflect light changed under up to nearly six million times normal atmospheric pressure (600 gigapascals) and at temperatures less than 1,700 degrees Celsius (about 3,140 degrees Fahrenheit). Reflectivity can indicate that a material is metallic.

    2
    A dynamic storm at the southern edge of Jupiter’s northern polar region dominates this Jovian cloudscape, courtesy of NASA’s Juno spacecraft. Image credits: NASA/JPL Caltech/SwRI/MSSS/Gerald Eichstädt/Seán Doran

    NASA/Juno

    They found that under about 1.5 million times normal atmospheric pressure (150 gigapascals) the deuterium switched from transparent to opaque—absorbing the light instead of allowing it to pass through. But a transition to metal-like reflectivity started at nearly 2 million times normal atmospheric pressure (200 gigapascals).

    “To build better models of potential exoplanetary architecture, this transition between gas and metallic liquid hydrogen must be demonstrated and understood,” Goncharov explained. “Which is why we focused on pinpointing the onset of reflectivity in compressed deuterium, moving us closer to a complete vision of this important process.”

    The research team included: Marius Millot, Dayne Fratanduono, Jon Eggert, J. Luc Peterson, Nathan Meezan, and Sebastien Le Pape of Lawrence Livermore National Laboratories; Stephanie Brygoo and Paul Loubeyre of the French Alternative Energies and Atomic Energy Commission’s Division of Military Applications; R. Stewart McWilliams of University of Edinburgh; J. Ryan Rygg and Gilbert Collins of University of Rochester (both also of LLNL); Raymond Jeanloz of University of California Berkeley; and Russell Hemley of George Washington University.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

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  • richardmitnick 9:19 am on August 7, 2018 Permalink | Reply
    Tags: , Carnegie Institution For Science, , , Pacific Ocean’s Effect on Arctic Warming   

    From Carnegie Institution for Science: “Pacific Ocean’s Effect on Arctic Warming” 

    Carnegie Institution for Science
    From Carnegie Institution for Science

    August 07, 2018

    1
    This image was taken in September 2016 showing the extent of Arctic sea ice then. The yellow line shows the average minimum extent of sea ice in the Arctic from 1981 to 2010. Image courtesy NASA

    New research, led by former Carnegie postdoctoral fellow Summer Praetorius, shows that changes in the heat flow of the northern Pacific Ocean may have a larger effect on the Arctic climate than previously thought. The findings are published in the August 7, 2018, issue of Nature Communications.

    The Arctic is experiencing larger and more rapid increases in temperature from global warming more than any other region, with sea-ice declining faster than predicted. This effect, known as Arctic amplification, is a well-established response that involves many positive feedback mechanisms in polar regions.

    What has not been well understood is how sea-surface temperature patterns and oceanic heat flow from Earth’s different regions, including the temperate latitudes, affect these polar feedbacks. This new research suggests that the importance of changes occurring in the Pacific may have a stronger impact on Arctic climate than previously recognized.

    Paleoclimate records show that climate change in the Arctic can be very large and happen very rapidly. During the last deglaciation, as the planet was starting to warm from rising greenhouse gases, there were two episodes of accelerated warming in the Arctic—with temperatures increasing by 15°C (27°F) in Greenland over the course of decades. Both events were accompanied by rapid warming in the mid-latitude North Pacific and North Atlantic oceans.

    Using these past changes as motivation for the current study, the research team* modeled a series of ocean-to-atmosphere heat flow scenarios for the North Pacific and the North Atlantic. They used the National Center for Atmospheric Research’s Community Earth System Model (CESM), to assess the impacts to the Arctic’s surface temperature and climate feedbacks.

    Praetorius, who was at Carnegie at the time of the research and is now with the USGS in Menlo Park, CA explained: “Since there appeared to be coupling between abrupt Arctic temperature changes and sea surface temperature changes in both the North Atlantic and North Pacific in the past, we thought it was important to untangle how each region may affect the Arctic differently in order to provide insight into recent and future Arctic changes.”

    The researchers found that both cooling and warming anomalies in the North Pacific resulted in greater global and Arctic surface air temperature anomalies than the same perturbations modeled for the North Atlantic. Until now, this sensitivity had been underappreciated.

    The scientists looked at several mechanisms that could be causing the changes and found that the strong global and Arctic changes depended on the magnitude of water vapor transfer from the mid-latitude oceans to the Arctic. When warm moist air is carried poleward towards the Arctic, it can lead to more low-lying clouds that act like a blanket, trapping warmth near the surface. The poleward movement of heat and moisture drive the Arctic’s sea-ice retreat and low-cloud formation, amplifying Arctic warming.

    The so-called ice-albedo feedback causes retreating ice and snow to lead to ever greater warming through increasing absorption of solar energy on darker surfaces.

    In very recent years, the Arctic has experienced an even greater acceleration in warming. The authors note that the unusually warm ocean temperatures in the Northeast Pacific paralleled the uptick in Arctic warming, possibly signaling a stronger link between these regions than generally recognized.

    “While this is a highly idealized study, our results suggest that changes in the Pacific Ocean may have a larger influence on the climate system than generally recognized,” remarked Carnegie coauthor Ken Caldeira.

    • Co-authors are Summer Praetorius, USGS, Menlo Park, CA; Maria Rugenstein, Institute for Atmospheric and Climate Science, Zurich; and Geeta Persad and Ken Caldeira of Carnegie’s Department of Global Ecology, Stanford, CA.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

     
  • richardmitnick 12:45 pm on July 17, 2018 Permalink | Reply
    Tags: , , , Carnegie Institution For Science, , Twelve new Jovian moons   

    From Carnegie Institution for Science: “A dozen new moons of Jupiter discovered, including one ‘oddball'” 

    Carnegie Institution for Science
    From Carnegie Institution for Science

    July 16, 2018

    Twelve new moons orbiting Jupiter have been found—11 “normal” outer moons, and one that they’re calling an “oddball.” This brings Jupiter’s total number of known moons to a whopping 79—the most of any planet in our Solar System.

    A team led by Carnegie’s Scott S. Sheppard first spotted the moons in the spring of 2017 while they were looking for very distant Solar System objects as part of the hunt for a possible massive planet far beyond Pluto.

    In 2014, this same team found the object with the most-distant known orbit in our Solar System and was the first to realize that an unknown massive planet at the fringes of our Solar System, far beyond Pluto, could explain the similarity of the orbits of several small extremely distant objects. This putative planet is now sometimes popularly called Planet X or Planet Nine. University of Hawaii’s Dave Tholen and Northern Arizona University’s Chad Trujillo are also part of the planet search team.

    “Jupiter just happened to be in the sky near the search fields where we were looking for extremely distant Solar System objects, so we were serendipitously able to look for new moons around Jupiter while at the same time looking for planets at the fringes of our Solar System,” said Sheppard.

    Gareth Williams at the International Astronomical Union’s Minor Planet Center used the team’s observations to calculate orbits for the newly found moons.

    “It takes several observations to confirm an object actually orbits around Jupiter,” Williams said. “So, the whole process took a year.”

    Nine of the new moons are part of a distant outer swarm of moons that orbit it in the retrograde, or opposite direction of Jupiter’s spin rotation. These distant retrograde moons are grouped into at least three distinct orbital groupings and are thought to be the remnants of three once-larger parent bodies that broke apart during collisions with asteroids, comets, or other moons. The newly discovered retrograde moons take about two years to orbit Jupiter.

    Two of the new discoveries are part of a closer, inner group of moons that orbit in the prograde, or same direction as the planet’s rotation. These inner prograde moons all have similar orbital distances and angles of inclinations around Jupiter and so are thought to also be fragments of a larger moon that was broken apart. These two newly discovered moons take a little less than a year to travel around Jupiter.

    “Our other discovery is a real oddball and has an orbit like no other known Jovian moon,” Sheppard explained. “It’s also likely Jupiter’s smallest known moon, being less than one kilometer in diameter”.

    This new “oddball” moon is more distant and more inclined than the prograde group of moons and takes about one and a half years to orbit Jupiter. So, unlike the closer-in prograde group of moons, this new oddball prograde moon has an orbit that crosses the outer retrograde moons.

    As a result, head-on collisions are much more likely to occur between the “oddball” prograde and the retrograde moons, which are moving in opposite directions.

    “This is an unstable situation,” said Sheppard. “Head-on collisions would quickly break apart and grind the objects down to dust.”

    It’s possible the various orbital moon groupings we see today were formed in the distant past through this exact mechanism.

    The team think this small “oddball” prograde moon could be the last-remaining remnant of a once-larger prograde-orbiting moon that formed some of the retrograde moon groupings during past head-on collisions. The name Valetudo has been proposed for it, after the Roman god Jupiter’s great-granddaughter, the goddess of health and hygiene.

    Elucidating the complex influences that shaped a moon’s orbital history can teach scientists about our Solar System’s early years.

    For example, the discovery that the smallest moons in Jupiter’s various orbital groups are still abundant suggests the collisions that created them occurred after the era of planet formation, when the Sun was still surrounded by a rotating disk of gas and dust from which the planets were born.

    Because of their sizes—one to three kilometers—these moons are more influenced by surrounding gas and dust. If these raw materials had still been present when Jupiter’s first generation of moons collided to form its current clustered groupings of moons, the drag exerted by any remaining gas and dust on the smaller moons would have been sufficient to cause them to spiral inwards toward Jupiter. Their existence shows that they were likely formed after this gas and dust dissipated.

    3
    Recovery images of Valetudo from the Magellan telescope in May 2018. The moon can be seen moving relative to the steady state background of distant stars. Jupiter is not in the field but off to the upper left.

    The initial discovery of most of the new moons were made on the Blanco 4-meter telescope at Cerro Tololo Inter-American in Chile and operated by the National Optical Astronomical Observatory of the United States. The telescope recently was upgraded with the Dark Energy Camera, making it a powerful tool for surveying the night sky for faint objects.

    Dark Energy Survey


    Dark Energy Camera [DECam], built at FNAL


    NOAO/CTIO Victor M Blanco 4m Telescope which houses the DECam at Cerro Tololo, Chile, housing DECam at an altitude of 7200 feet

    Several telescopes were used to confirm the finds, including the 6.5-meter Magellan telescope at Carnegie’s Las Campanas Observatory in Chile; the 4-meter Discovery Channel Telescope at Lowell Observatory Arizona (thanks to Audrey Thirouin, Nick Moskovitz and Maxime Devogele); the 8-meter Subaru Telescope and the University of Hawaii 2.2 meter telescope (thanks to Dave Tholen and Dora Fohring at the University of Hawaii); and 8-meter Gemini Telescope in Hawaii (thanks to Director’s Discretionary Time to recover Valetudo). Bob Jacobson and Marina Brozovic at NASA’s Jet Propulsion Laboratory confirmed the calculated orbit of the unusual oddball moon in 2017 in order to double check its location prediction during the 2018 recovery observations in order to make sure the new interesting moon was not lost.

    Carnegie 6.5 meter Magellan Baade and Clay Telescopes located at Carnegie’s Las Campanas Observatory, Chile. over 2,500 m (8,200 ft) high

    Discovery Channel Telescope at Lowell Observatory, Happy Jack AZ, USA, Altitude 2,360 m (7,740 ft)


    NAOJ/Subaru Telescope at Mauna Kea Hawaii, USA,4,207 m (13,802 ft) above sea level


    U Hawaii 2.2 meter telescope, Mauna Kea, Hawaii, USA,4,207 m (13,802 ft) above sea level


    Gemini/North telescope at Maunakea, Hawaii, USA,4,207 m (13,802 ft) above sea level

    5

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

     
  • richardmitnick 10:24 am on July 10, 2018 Permalink | Reply
    Tags: , , , Carnegie Institution For Science, , Rocky planet neighbor looks familiar but is not Earth’s twin, Ross 128 b   

    From Carnegie Institution for Science: “Rocky planet neighbor looks familiar, but is not Earth’s twin” 

    Carnegie Institution for Science
    From Carnegie Institution for Science

    July 10, 2018

    1
    This artist’s impression shows the temperate planet Ross 128 b, with its red dwarf parent star in the background. It is provided courtesy of ESO/M. Kornmesser.

    Last autumn, the world was excited by the discovery of an exoplanet called Ross 128 b, which is just 11 light years away from Earth. New work [The Astrophysical Letters] from a team led by Diogo Souto of Brazil’s Observatório Nacional and including Carnegie’s Johanna Teske has for the first time determined detailed chemical abundances of the planet’s host star, Ross 128.

    Understanding which elements are present in a star in what abundances can help researchers estimate the makeup of the exoplanets that orbit them, which can help predict how similar the planets are to the Earth.

    “Until recently, it was difficult to obtain detailed chemical abundances for this kind of star,” said lead author Souto, who developed a technique to make these measurements last year.

    Like the exoplanet’s host star Ross 128, about 70 percent of all stars in the Milky Way are red dwarfs, which are much cooler and smaller than our Sun. Based on the results from large planet-search surveys, astronomers estimate that many of these red dwarf stars host at least one exoplanet. Several planetary systems around red dwarfs have been newsmakers in recent years, including Proxima b, a planet which orbits the nearest star to our own Sun, Proxima Centauri, and the seven planets of TRAPPIST-1, which itself is not much larger in size than our Solar System’s Jupiter.

    Centauris Alpha Beta Proxima 27, February 2012. Skatebiker

    A size comparison of the planets of the TRAPPIST-1 system, lined up in order of increasing distance from their host star. The planetary surfaces are portrayed with an artist’s impression of their potential surface features, including water, ice, and atmospheres. NASA

    Using the Sloan Digital Sky Survey’s APOGEE spectroscopic instrument, the team measured the star’s near-infrared light to derive abundances of carbon, oxygen, magnesium, aluminum, potassium, calcium, titanium, and iron.

    SDSS APOGEE spectrograph

    SDSS Telescope at Apache Point Observatory, near Sunspot NM, USA, Altitude 2,788 meters (9,147 ft)

    “The ability of APOGEE to measure near-infrared light, where Ross 128 is brightest, was key for this study,” Teske said. “It allowed us to address some fundamental questions about Ross 128 b’s `Earth-like-ness’,” Teske said.

    When stars are young, they are surrounded by a disk of rotating gas and dust from which rocky planets accrete. The star’s chemistry can influence the contents of the disk, as well as the resulting planet’s mineralogy and interior structure. For example, the amount of magnesium, iron, and silicon in a planet will control the mass ratio of its internal core and mantle layers.

    The team determined that Ross 128 has iron levels similar to our Sun. Although they were not able to measure its abundance of silicon, the ratio of iron to magnesium in the star indicates that the core of its planet, Ross 128 b, should be larger than Earth’s.

    Because they knew Ross 128 b’s minimum mass, and stellar abundances, the team was also able to estimate a range for the planet’s radius, which is not possible to measure directly due to the way the planet’s orbit is oriented around the star.

    Knowing a planet’s mass and radius is important to understanding what it’s made of, because these two measurements can be used to calculate its bulk density. What’s more, when quantifying planets in this way, astronomers have realized that planets with radii greater than about 1.7 times Earth’s are likely surrounded by a gassy envelope, like Neptune, and those with smaller radii are likely to be more-rocky, as is our own home planet.

    The estimated radius of Ross 128 b indicates that it should be rocky.

    Lastly, by measuring the temperature of Ross 128 and estimating the radius of the planet the team was able to determine how much of the host star’s light should be reflecting off the surface of Ross 128 b, revealing that our second-closest rocky neighbor likely has a temperate climate.

    “It’s exciting what we can learn about another planet by determining what the light from its host star tells us about the system’s chemistry,” Souto said. “Although Ross 128 b is not Earth’s twin, and there is still much we don’t know about its potential geologic activity, we were able to strengthen the argument that it’s a temperate planet that could potentially have liquid water on its surface.”

    This work was supported by NASA’s Astrophysics Division of the Science Mission Directorate, the Spanish Ministry of Economy and Competitiveness, the U.S. National Science Foundation, CONICYT, the Crafoord Foundation, and Stiftelsen Olle Engkvist Byggmästare.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

     
  • richardmitnick 6:12 pm on March 21, 2018 Permalink | Reply
    Tags: Are you rocky or are you gassy? Carnegie astronomers help unlock the mysteries of super-Earths, , , , Carnegie Institution For Science, Chile at 8200ft, , Magellan Clay and Baade telescopes at Las Campanas, Planet Finder Spectrograph on the Magellan Clay telescope   

    From Carnegie: “Are you rocky or are you gassy? Carnegie astronomers help unlock the mysteries of super-Earths” 

    Carnegie Institution for Science
    Carnegie Institution for Science

    February 08, 2018
    Spring Letter

    1
    An artist’s conception of a system with three super-Earth exoplanets, courtesy of ESO.

    A star about 100 light years away in the Pisces constellation, GJ 9827, hosts what may be one of the most massive and dense super-Earth planets detected to date, according to new research led by Carnegie’s Johanna Teske. This new information [In press inAJ] provides evidence to help astronomers better understand the process by which such planets form.

    The GJ 9827 star actually hosts a trio of planets, discovered by NASA’s exoplanet-hunting Kepler/K2 mission, and all three are slightly larger than Earth. This is the size that the Kepler mission determined to be most common in the galaxy with periods between a few and several-hundred-days.

    Intriguingly, no planets of this size exist in our Solar System. This makes scientists curious about the conditions under which they form and evolve.

    One important key to understanding a planet’s history is to determine its composition. Are these super-Earths rocky like our own planet? Or do they have solid cores surrounded by large, gassy atmospheres?

    To try to understand what an exoplanet is made of, scientists need to measure both its mass and its radius, which allows them to determine its bulk density.

    When quantifying planets in this way, astronomers have noticed a trend. It turns out that planets with radii greater than about 1.7 times that of Earth are have a gassy envelope, like Neptune, and those with radii smaller than this are rocky, like our home planet.

    Some researchers have proposed that this difference is caused by photoevaporation, which strips planets of their surrounding envelope of so-called volatiles—substances like water and carbon dioxide that have low boiling points—creating smaller-radius planets. But more information is needed to truly test this theory.

    This is why GJ 9827’s three planets are special—with radii of 1.64 (planet b), 1.29 (planet c) and 2.08 (planet d), they span this dividing line between super-Earth (rocky) and sub-Neptune (somewhat gassy) planets.

    Luckily, teams of Carnegie scientists including co-authors Steve Shectman, Sharon Wang, Paul Butler, Jeff Crane, and Ian Thompson, have been monitoring GJ 9827 with their Planet Finding Spectrograph (PFS), so they were able to constrain the masses of the three planets with data in hand, rather than having to scramble to get many new observations of GJ 9827.

    Carnegie Planet Finder Spectrograph on the Magellan Clay telescope at Las Campanas, Chile, Altitude 2,380 m (7,810 ft)

    “Usually, if a transiting planet is detected, it takes months if not a year or more to gather enough observations to measure its mass,” Teske explained. “Because GJ 9827 is a bright star, we happened to have it in the catalog of stars that Carnegie astronomers been monitoring for planets since 2010. This was unique to PFS.”

    The spectrograph was developed by Carnegie scientists and mounted on the Magellan Clay Telescopes at Carnegie’s Las Campanas Observatory.

    Carnegie 6.5 meter Magellan Baade and Clay Telescopes located at Carnegie’s Las Campanas Observatory, Chile. over 2,500 m (8,200 ft) high

    The PFS observations indicate that planet b is roughly eight times the mass of Earth, which would make it one of the most-massive and dense super-Earths yet discovered. The masses for planet c and planet d are estimated to be about two and a half and four times that of Earth respectively, although the uncertainty in these two determinations is very high.

    This information suggests that planet d has a significant volatile envelope, and leaves open the question of whether planet c has a volatile envelope or not. But the better constraint on the mass of planet b suggests that that it is roughly 50 percent iron.

    “More observations are needed to pin down the compositions of these three planets,” Wang said. “But they do seem like some of the best candidates to test our ideas about how super-Earths form and evolve, potentially using NASA’s upcoming James Webb Space Telescope.”

    Angie Wolfgang, an NSF Postdoctoral Fellow from Penn State University, is also a co-author on the paper.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

     
  • richardmitnick 4:06 pm on February 28, 2018 Permalink | Reply
    Tags: , Carnegie Institution For Science, ,   

    From Carnegie Institution for Science: “Modern volcanism tied to events occurring soon after Earth’s birth” 

    Carnegie Institution for Science
    Carnegie Institution for Science

    February 27, 2018

    Plumes of hot magma from the volcanic hotspot that formed Réunion Island in the Indian Ocean rise from an unusually primitive source deep beneath the Earth’s surface, according to new work in Nature from Carnegie’s Bradley Peters, Richard Carlson, and Mary Horan along with James Day of the Scripps Institution of Oceanography.

    Réunion marks the present-day location of the hotspot that 66 million years ago erupted the Deccan Traps flood basalts, which cover most of India and may have contributed to the extinction of the dinosaurs. Flood basalts and other hotspot lavas are thought to originate from different portions of Earth’s deep interior than most volcanoes at Earth’s surface and studying this material may help scientists understand our home planet’s evolution.

    1
    A fieldwork photo from Réunion Island shows the flank of the Cirque de Cilaos, looking out towards the Indian Ocean courtesy of Bradley Peters.

    3
    Looking into down into a volcanic crater of Piton de la Fournaise on Réunion Island with dormant volcanic cones in the background. Photo is courtesy of Bradley Peters.

    The heat from Earth’s formation process caused extensive melting of the planet, leading Earth to separate into two layers when the denser iron metal sank inward toward the center, creating the core and leaving the silicate-rich mantle floating above.

    Over the subsequent 4.5 billion years of Earth’s evolution, deep portions of the mantle would rise upwards, melt, and then separate once again by density, creating Earth’s crust and changing the chemical composition of Earth’s interior in the process. As crust sinks back into Earth’s interior—a phenomenon that’s occurring today along the boundary of the Pacific Ocean—the slow motion of Earth’s mantle works to stir these materials, along with their distinct chemistry, back into the deep Earth.

    But not all of the mantle is as well-blended as this process would indicate. Some older patches still exist—like powdery pockets in a poorly mixed bowl of cake batter. Analysis of the chemical compositions of Réunion Island volcanic rocks indicate that their source material is different from other, better-mixed parts of the modern mantle.

    Using new isotope data, the research team revealed that Réunion lavas originate from regions of the mantle that were isolated from the broader, well-blended mantle. These isolated pockets were formed within the first ten percent of Earth’s history.

    Isotopes are elements that have the same number of protons, but a different number of neutrons. Sometimes, the number of neutrons present in the nucleus make an isotope unstable; to gain stability, the isotope will release energetic particles in the process of radioactive decay. This process alters its number of protons and neutrons and transforms it into a different element. This new study harnesses this process to provide a fingerprint for the age and history of distinct mantle pockets.

    Samarium-146 is one such unstable, or radioactive, isotope with a half-life of only 103 million years. It decays to the isotope neodymium-142. Although samarium-146 was present when Earth formed, it became extinct very early in Earth’s infancy, meaning neodymium-142 provides a good record of Earth’s earliest history, but no record of the Earth from the period after all the samarium-146 transformed into neodymium-142. Differences in the abundances of neodymium-142 in comparison to other isotopes of neodymium could only have been generated by changes in the chemical composition of the mantle that occurred in the first 500 million years of Earth’s 4.5 billion-year history.

    The ratio of neodymium-142 to neodymium-144 in Réunion volcanic rocks, together with the results of lab-based mimicry and modeling studies, indicate that despite billions of years of mantle mixing, Réunion plume magma likely originates from a preserved pocket of the mantle that experienced a compositional change caused by large-scale melting of the Earth’s earliest mantle.

    The team’s findings could also help explain the origin of dense regions right at the boundary of the core and mantle called large low shear velocity provinces (LLSVPs) and ultralow velocity zones (ULVZs), reflecting the unusually slow speed of seismic waves as they travel through these regions of the deep mantle. Such regions may be relics of early melting events.

    “The mantle differentiation event preserved in these hotspot plumes can both teach us about early Earth geochemical processes and explain the mysterious seismic signatures created by these dense deep-mantle zones,” said lead author Peters.

    Funding for fieldwork for this study was provided by the National Geographic Society (NGS 8330-07), the Geological Society of America (GSA 10539-14), and by a generous personal donation from Dr. R. Rex. Support for laboratory work was provided by Carnegie Institution for Science.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

     
  • richardmitnick 12:06 pm on February 27, 2018 Permalink | Reply
    Tags: 2MASS J13243553+6358281, , , , , Carnegie Institution For Science,   

    From Carnegie Institution for Science: “When do aging brown dwarfs sweep the clouds away? “ 

    Carnegie Institution for Science
    Carnegie Institution for Science

    February 26, 2018
    No writer credit

    1
    An artist’s conception of a brown dwarf. Image is courtesy of NASA/JPL, slightly modified by Jonathan Gagné.

    Brown dwarfs, the larger cousins of giant planets, undergo atmospheric changes from cloudy to cloudless as they age and cool. A team of astronomers led by Carnegie’s Jonathan Gagné measured for the first time the temperature at which this shift happens in young brown dwarfs. Their findings, published by The Astrophysical Journal Letters, may help them better understand how gas giant planets like our own Solar System’s Jupiter evolved.

    Brown dwarfs are too small to sustain the hydrogen fusion process that fuels stars and allows them to remain hot and bright for a long time. After formation, brown dwarfs slowly cool down and contract over time—at some point shifting from heavily cloud covered to having completely clear skies.

    Because they are freely floating in space, the atmospheric properties of brown dwarfs are much easier to study than the atmospheres of exoplanets, where the light of a central star can be completely overwhelming.

    In this paper, Gagné and his colleagues—Katelyn Allers of Bucknell University; Christopher Theissen of University of California San Diego; Jacqueline Faherty and Daniella Bardalez Gagliuffi of the American Museum of Natural History, and Etienne Artigau of Institute for Research on Exoplanets, Université de Montréal—focused on an unusually red brown dwarf called 2MASS J13243553+6358281, which they were able to determine is one of the nearest known planetary mass objects to our Solar System.

    The redness of this object had previously been suggested to indicate that it was actually a binary system, but the research team’s findings indicate that it is a single free floating planetary mass object.

    They confirmed that it is part of a group of roughly 80 stars of similar ages and compositions drifting together through space, called the AB Doradus moving group, which revealed that it is about 150 million years old.

    By knowing the object’s age and measuring its luminosity and distance, the team could determine its likely radius, mass, and, most-importantly its temperature.

    They could then compare its temperature to that of another previously studied brown dwarf in the same moving group—one that was still cloudy while 2MASS J1324+6358 was already cloudless. This allowed them to figure out the temperature at which the cloudy to cloudless transition happens.

    “We were able to constrain the point in the cool-down process at which brown dwarfs like J1324transition from cloudy to cloud-free,” explained Gagné

    The shift occurs about 1,150 degrees kelvin, or 1,600 degrees Fahrenheit, for planetary-mass objects that are 150 million years old like 2MASS J1324+6358 and other members of the AB Doradus moving group.

    “Because brown dwarfs like this one are so analogous to gas giant planets, this information could help us understand some of the evolutionary processes that occurred right here in our own Solar System’s history,” Gagné added.

    This research made use of data products from the Two Micron All Sky Survey (2MASS), which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center (IPAC)/California Institute of Technology (Caltech), funded by the National Aeronautics and Space Administration (NASA) and the National Science Foundation; and data products from the Wide-field Infrared Survey Explorer (WISE), which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory (JPL)/Caltech, funded by NASA. Based on observations obtained at the Gemini Observatory (science program number GN2017B-FT-21) acquired through the Gemini Observatory Archive, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnologia e Innovacion Productiva (Argentina), and Ministerio da Ciencia, Tecnologia e Inova¸cao (Brazil).


    Caltech 2MASS Telescopes, a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center (IPAC) at Caltech, at the Whipple Observatory on Mt. Hopkins south of Tucson, AZ, and at the Cerro Tololo Inter-American Observatory near La Serena, Chile.

    NASA/WISE Telescope

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

     
  • richardmitnick 10:57 am on February 12, 2018 Permalink | Reply
    Tags: , , , Carnegie Institution For Science, Chilean Astronomy, , , , , LSST telescope   

    From Forbes: “Chile’s Pristine Skies Are Key To Astronomy’s Next Generation Of Telescopes” 

    ForbesMag

    Forbes Magazine

    Jan 31, 2018
    Bruce Dorminey

    Long known for its copper, sea bass and merlot wine, Chile’s most profound export may be data that its astronomical observatories mine nightly from its pristine skies.

    1
    Exoplanet hunters at ESO’s La Silla Observatory in Chile. ESO.

    Because Chile’s ground-based window onto our Milky Way’s galactic center is arguably unmatched, the European Southern Observatory (ESO) first set up shop here more than a half century ago. Today, their 15 member states enjoy facilities at three major observatories.

    “ESO spends 80 million euros [$100 million] a year for its operations in Chile and is the biggest astronomical operation here,” astrophysicist Fernando Comeron, ESO’s Representative in Chile, told me during a recent visit to ESO’s offices in Vitacura, a tony enclave of Santiago.

    To its credit, ESO never rests on its laurels. When I first arrived here two decades ago during research for my book Distant Wanderers, I was amazed that even before ESO’s Very Large Telescope (VLT) was finished, there was already talk of the next big thing.

    ESO VLT Platform at Cerro Paranal elevation 2,635 m (8,645 ft)

    Initially, that next big thing was to be a 100-meter Overwhelming Large Telescope (OWL). But after several years of study, ESO put that concept in stasis and instead pursued a project that it felt was more practical and technologically feasible. Thus, in 2014, ESO broke ground for its European-Extremely Large Telescope (E-ELT) at Paranal Observatory in northern Chile’s Atacama desert.

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile, at an altitude 3,046 m (9,993 ft)

    Due for scientific first light in November 2024, once completed it will be the world’s largest optical/infrared telescope. That is, a $1.4 billion behemoth with a 39.3-meter primary mirror; itself a composition of 798 individual 1.4-meter segments.

    The best telescopes in the world are now in the Southern hemisphere says Comeron, noting that the Chilean government takes its responsibility in preserving observing conditions very seriously. In fact, he says, even through the country’s turbulent political history, ESO continued to function here.

    “We have 50 years of dealing with the Chilean government and it’s been a very fruitful relationship and is not subjected to changes of government or politics,” said Comeron.

    And more are coming. The E-ELT and other new telescopes being built in Chile, like the Large Synoptic Survey Telescope (LSST) and the Giant Magellan Telescope (GMT), are forever changing the Chilean astronomical landscape.


    LSST telescope, currently under construction 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.

    Giant Magellan Telescope, to be at the Carnegie Institution for Science’s Las Campanas Observatory, to be built some 115 km (71 mi) north-northeast of La Serena, Chile, over 2,500 m (8,200 ft) high

    “The Chilean astronomy community is growing; universities are opening undergraduate and graduate programs in astronomy and attracting international researchers to be part of their institutions,” Barbara Rojas-Ayala, an astronomer at the Universidad Andrés Bello in Santiago, told me.

    What makes Chile so astronomically special?

    Very dry northern deserts which border a lengthy coastline and the Humboldt Current.

    The Humboldt Current, sometimes referred to as the Peru Current, is a 550-mile-wide cold ocean current that originates in Antarctica and runs north along the South American coastline. Its temperatures help keep Chile’s northern desert air even drier. Cloud cover is confined to altitudes of about 3000 feet, says Comeron.

    As a result, he says you find very dry conditions at much lower altitudes in Chile. But it’s also why despite Chile’s thousands of miles of extraordinarily beautiful coastline, the country is not known for beach-life.

    “The water is even freezing in summer,” said Comeron.

    What will the E-ELT bring to the table?

    The ability to see earth-like planets at one Earth-Sun distance from their star to look for the spectroscopic signatures of life.

    And Comeron predicts the E-ELT will give astronomers at least some spectra that will be debated as containing biosignatures.

    In terms of cosmology, the new telescope should also shed light on:

    — Whether the laws of nature are truly universal;

    — Individual stellar populations within galaxies out to distances of tens of millions of light-years; and,

    — Observe back in cosmic time to before the onset of the first stars which will help astronomers determine how galaxies formed and evolved across the breadth of the cosmos.

    And as for the burgeoning Chilean astronomy community?

    “Chile is on the way to becoming a net producer of astronomers with more going abroad than staying here,” said Comeron. “For ESO, we have about 600 astronomers coming here per year.”

    However, Comeron says a few thousand astronomers per year use all of Chile’s facilities.

    Considering all the data that will be acquired with observatories within our country, there is a lack of funding for local researchers who could data-mine these large astronomical projects, says Rojas-Ayala.

    In central Santiago, Rojas-Ayala says it’s impossible to distinguish the Milky Way and the Magellan Clouds. As a result, she says there are now initiatives to restrict blue light emissions and luminous LED/plasma signs in an effort to protect northern Chile’s precious night skies.

    As for the E-ELT’s ultimate legacy?

    It has a nominal operating lifetime of at least 30 years. But Comeron expects it will still be operational well into the 22nd century and although astronomers have some ideas about what this new behemoth will observe in its first few years, beyond that it’s anyone’s guess.

    “It’s almost science fiction as to what we will be observing,” said Comeron. “I haven’t a clue but it’s going to be exciting.”

    See the full article here.

    Please help promote STEM in your local schools.

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    Stem Education Coalition

     
  • richardmitnick 2:57 pm on February 8, 2018 Permalink | Reply
    Tags: , , , Carnegie Institution For Science, , GJ 9827, Planet Finding Spectrograph   

    From Carnegie: “Are you rocky or are you gassy? Carnegie astronomers help unlock the mysteries of super-Earths “ 

    Carnegie Institution for Science
    Carnegie Institution for Science

    February 08, 2018

    1
    An artist’s conception of a system with three super-Earth exoplanets, courtesy of ESO.

    A star about 100 light years away in the Pisces constellation, GJ 9827, hosts what may be one of the most massive and dense super-Earth planets detected to date according to new research led by Carnegie’s Johanna Teske. This new information [AJ] provides evidence to help astronomers better understand the process by which such planets form.

    The GJ 9827 star actually hosts a trio of planets, discovered by NASA’s exoplanet-hunting Kepler/K2 mission, and all three are slightly larger than Earth. This is the size that the Kepler mission determined to be most common in the galaxy with periods between a few and several-hundred-days.

    Intriguingly, no planets of this size exist in our Solar System. This makes scientists curious about the conditions under which they form and evolve.

    One important key to understanding a planet’s history is to determine its composition. Are these super-Earths rocky like our own planet? Or do they have solid cores surrounded by large, gassy atmospheres?

    To try to understand what an exoplanet is made of, scientists need to measure both its mass and its radius, which allows them to determine its bulk density.

    When quantifying planets in this way, astronomers have noticed a trend. It turns out that planets with radii greater than about 1.7 times that of Earth are have a gassy envelope, like Neptune, and those with radii smaller than this are rocky, like our home planet.

    Some researchers have proposed that this difference is caused by photoevaporation, which strips planets of their surrounding envelope of so-called volatiles—substances like water and carbon dioxide that have low boiling points—creating smaller-radius planets. But more information is needed to truly test this theory.

    This is why GJ 9827’s three planets are special—with radii of 1.64 (planet b), 1.29 (planet c) and 2.08 (planet d), they span this dividing line between super-Earth (rocky) and sub-Neptune (somewhat gassy) planets.

    Luckily, teams of Carnegie scientists including co-authors Steve Shectman, Sharon Wang, Paul Butler, Jeff Crane, and Ian Thompson, have been monitoring GJ 9827 with their Planet Finding Spectrograph (PFS), so they were able to constrain the masses of the three planets with data in hand, rather than having to scramble to get many new observations of GJ 9827.

    2
    Planet Finding Spectrograph (PFS) on the 6.5 meter on the Magellan Clay telescope at Las Campanas, Chile

    “Usually, if a transiting planet is detected, it takes months if not a year or more to gather enough observations to measure its mass,” Teske explained. “Because GJ 9827 is a bright star, we happened to have it in the catalog of stars that Carnegie astronomers been monitoring for planets since 2010. This was unique to PFS.”

    The spectrograph was developed by Carnegie scientists and mounted on the Magellan Clay Telescopes at Carnegie’s Las Campanas Observatory.

    The PFS observations indicate that planet b is roughly eight times the mass of Earth, which would make it one of the most-massive and dense super-Earths yet discovered. The masses for planet c and planet d are estimated to be about two and a half and four times that of Earth respectively, although the uncertainty in these two determinations is very high.

    This information suggests that planet d has a significant volatile envelope, and leaves open the question of whether planet c has a volatile envelope or not. But the better constraint on the mass of planet b suggests that that it is roughly 50 percent iron.

    “More observations are needed to pin down the compositions of these three planets,” Wang said. “But they do seem like some of the best candidates to test our ideas about how super-Earths form and evolve, potentially using NASA’s upcoming James Webb Space Telescope.”

    Angie Wolfgang, an NSF Postdoctoral Fellow from Penn State University, is also a co-author on the paper.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

     
  • richardmitnick 12:41 pm on January 20, 2018 Permalink | Reply
    Tags: , , , Carnegie Institution For Science, , , Meteoritic stardust unlocks timing of supernova dust formation, Type II supernovae   

    From Carnegie Institution for Science: “Meteoritic stardust unlocks timing of supernova dust formation” 

    Carnegie Institution for Science
    Carnegie Institution for Science

    January 18, 2018
    Conel Alexander
    Larry Nittler

    Dust is everywhere—not just in your attic or under your bed, but also in outer space. To astronomers, dust can be a nuisance by blocking the light of distant stars, or it can be a tool to study the history of our universe, galaxy, and Solar System.

    For example, astronomers have been trying to explain why some recently discovered distant, but young, galaxies contain massive amounts of dust. These observations indicate that type II supernovae—explosions of stars more than ten times as massive as the Sun—produce copious amounts of dust, but how and when they do so is not well understood.

    1
    An electron microscope image of a micron-sized supernova silicon carbide, SiC, stardust grain (lower right) extracted from a primitive meteorite. Such grains originated more than 4.6 billion years ago in the ashes of Type II supernovae, typified here by a Hubble Space Telescope image of the Crab Nebula, the remnant of a supernova explosion in 1054. Laboratory analysis of such tiny dust grains provides unique information on these massive stellar explosions. (1 μm is one millionth of a meter.) Image credits: NASA and Larry Nittler.

    New work from a team of Carnegie cosmochemists published by Science Advances reports analyses of carbon-rich dust grains extracted from meteorites that show that these grains formed in the outflows from one or more type II supernovae more than two years after the progenitor stars exploded. This dust was then blown into space to be eventually incorporated into new stellar systems, including in this case, our own.

    The researchers—led by former-postdoctoral fellow Nan Liu, along with Larry Nittler, Conel Alexander, and Jianhua Wang of Carnegie’s Department of Terrestrial Magnetism—came to their conclusion not by studying supernovae with telescopes. Rather, they analyzed microscopic silicon carbide, SiC, dust grains that formed in supernovae more than 4.6 billion years ago and were trapped in meteorites as our Solar System formed from the ashes of the galaxy’s previous generations of stars.

    Some meteorites have been known for decades to contain a record of the original building blocks of the Solar System, including stardust grains that formed in prior generations of stars.

    “Because these presolar grains are literally stardust that can be studied in detail in the laboratory,” explained Nittler, “they are excellent probes of a range of astrophysical processes.”

    For this study, the team set out to investigate the timing of supernova dust formation by measuring isotopes—versions of elements with the same number of protons but different numbers of neutrons—in rare presolar silicon carbide grains with compositions indicating that they formed in type II supernovae.

    Certain isotopes enable scientists to establish a time frame for cosmic events because they are radioactive. In these instances, the number of neutrons present in the isotope make it unstable. To gain stability, it releases energetic particles in a way that alters the number of protons and neutrons, transmuting it into a different element.

    The Carnegie team focused on a rare isotope of titanium, titanium-49, because this isotope is the product of radioactive decay of vanadium-49 which is produced during supernova explosions and transmutes into titanium-49 with a half-life of 330 days. How much titanium-49 gets incorporated into a supernova dust grain thus depends on when the grain forms after the explosion.

    Using a state-of-the-art mass spectrometer to measure the titanium isotopes in supernova SiC grains with much better precision than could be accomplished by previous studies, the team found that the grains must have formed at least two years after their massive parent stars exploded.

    Because presolar supernova graphite grains are isotopically similar in many ways to the SiC grains, the team also argues that the delayed formation timing applies generally to carbon-rich supernova dust, in line with some recent theoretical calculations.

    “This dust-formation process can occur continuously for years, with the dust slowly building up over time, which aligns with astronomer’s observations of varying amounts of dust surrounding the sites of stellar explosions,” added lead author Liu. “As we learn more about the sources for dust, we can gain additional knowledge about the history of the universe and how various stellar objects within it evolve.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

     
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