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  • richardmitnick 11:00 am on January 16, 2020 Permalink | Reply
    Tags: "How far is Betelgeuse?", , , , , , EarthSky   

    From ALMA via EarthSky: “How far is Betelgeuse?” 

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

    From ALMA

    via

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    EarthSky

    January 16, 2020

    Recent speculation that Betelgeuse might be on the verge of going supernova prompted many to ask: how far away is it? But getting a distance measurement for this star has been no easy task.

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    An image of Betelgeuse taken at sub-millimeter wavelengths by the Atacama Large Millimeter/submillimeter Array (ALMA). It shows a section of hot gas slightly protruding from the red giant star’s extended atmosphere. Some of the data used to compute the latest parallax for Betelgeuse came from observations by ALMA. Image via ALMA.

    Betelgeuse, the bright red star in the constellation of Orion the Hunter, is in the end stage of its stellar life. Astronomers have long thought it will someday explode to become a supernova. In late 2019 and early 2020, Betelgeuse generated a lot of chatter on social media among astronomers. They wondered, somewhat jokingly, if an explosion were imminent because the star has dimmed, unprecedentedly, by a noticeable amount since late October 2019. As the news went mainstream, many people wondered how far Betelgeuse was from us and if an explosion could hurt life on Earth. The good news is that if Betelgeuse explodes, it is close enough to put on a spectacular light show, but far enough to not cause us on Earth any harm. To answer the distance question first, Betelgeuse is approximately 724 light-years away. But getting that answer, even for a relatively nearby star, is surprisingly difficult.

    It’s only in the last 30 years, with the use of new technologies, that astronomers have obtained more accurate measurements for the distance to Betelgeuse and other nearby stars. This advance began in 1989, when the European Space Agency (ESA) launched a space telescope called Hipparcos, named after the famous Greek astronomer Hipparchus.

    ESA/Hipparcos satellite

    Over several years of observations, the Hipparcos space telescope provided parallax and distance data for more than 100,000 relatively nearby stars.

    Those measurements became the basis for most of the estimated distances to stars that you see today.

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    When viewed from two locations, there is a slight shift in the position of a nearby star with respect to distant background stars. For observations on Earth, taken six months apart, the separation between those two locations is the diameter of Earth’s orbit. The angle alpha is the parallax angle. Image via P.wormer / Wikimedia Commons.

    The original Hipparcos data gave a parallax of 7.63 milliarcseconds for Betelgeuse; that’s about one-millionth the width of the full moon. Computations based on that parallax yielded a distance of about 430 light-years.

    However, Betelgeuse is what’s known as a variable star because its brightness fluctuates with time (that said, the recent excitement over Betelgeuse’s dimming is because it’s the biggest dip in brightness ever observed). And therein began the difficulty in estimating Betelgeuse’s distance.

    That’s because subsequent studies found an error in the methods used for reducing the Hipparcos data for variable stars. An effort to correct those errors gave a parallax of 5.07 milliarcseconds, changing Betelgeuse’s estimated distance from 430 light-years to about 643 light-years, plus or minus 46 light-years.

    But wait, there’s more. In 2017, astronomers published new calculations that further refined Betelgeuse’s parallax to 4.51 milliiarcseconds. This new analysis of data from Hipparcos also included observations from several ground-based radio telescopes. That placed Betelgeuse at a distance of about 724 light-years, or, more accurately, between 613 and 881 light-years when data uncertainties are included.

    You might know that the European Space Agency’s Gaia astrometry mission has the goal of making a three-dimensional map of our Milky Way galaxy.

    ESA/GAIA satellite

    At the time of its second data release in April 2018, ESA said Gaia’s data had already made possible:

    “… the richest star catalog to date, including high-precision measurements of nearly 1.7 billion stars….”

    Yet Betelgeuse is not one of those stars, and Gaia won’t be used to find a more precise distance for Betelgeuse. The reason is that Betelgeuse is too bright for the spacecraft’s sensors.

     
  • richardmitnick 8:43 am on January 12, 2020 Permalink | Reply
    Tags: "Astronomers find wandering black holes in dwarf galaxies", , Astrophysicist Amy Reines, , , , EarthSky, ,   

    From Montana State University via Earth Sky: Women in STEM-“Astronomers find wandering black holes in dwarf galaxies” Astrophysicist Amy Reines 

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    via

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    EarthSky

    January 10, 2020

    Eleanor Imster

    They found massive black holes in 13 dwarf galaxies, which are now among the smallest galaxies known to host such massive black holes. In roughly half the galaxies, the black hole isn’t at the galactic center, but instead is “wandering.”

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    Artist’s concept of a dwarf galaxy, its shape distorted, most likely by a past interaction with another galaxy, and a massive black hole in its outskirts (bright spot, far right). Image via Sophia Dagnello/ NRAO/ AUI/ NSF.

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    It’s an amazing aspect of our knowledge of the modern universe that – everywhere we look – large galaxies have supermassive black holes at their centers. Now a team of astronomers has spotted 13 massive black holes in dwarf galaxies, located less than a billion light-years from Earth. All 13 galaxies are more than 100 times less massive than our own Milky Way. That makes them among the smallest galaxies known to host massive black holes. The astronomers announced the discovery at the American Astronomical Society’s recent meeting in Honolulu, Hawaii (January 4-8, 2020).

    The astronomers estimate that the black holes in these smaller galaxies average about 400,000 times the mass of our sun. That’s in contrast to the supermassive black hole at our galaxy’s center, which is about 4 million times the sun’s mass.

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    Astrophysicist Amy Reines. Image via Montana State University.

    Amy Reines of Montana State University led the new study, which was published January 3 in the peer-reviewed The Astrophysical Journal. She said in a statement:

    ” The new … observations revealed that 13 of these galaxies have strong evidence for a massive black hole that is actively consuming surrounding material.

    We were very surprised to find that, in roughly half of those 13 galaxies, the black hole is not at the center of the galaxy, unlike the case in larger galaxies.”

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    Visible-light images of dwarf galaxies now shown to have massive black holes. Center illustration is an artist’s concept of the rotating disk of material falling into such a black hole, and the jets of material propelled outward. Image via Sophia Dagnello/ NRAO/ AUI/ NSF/ DECaLS survey/ CTIO.

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    The astronomers used the Karl G. Jansky Very Large Array (VLA) – on the Plains of San Agustin in central New Mexico – to make the discovery.

    NRAO/Karl V Jansky Expanded Very Large Array, on the Plains of San Agustin fifty miles west of Socorro, NM, USA, at an elevation of 6970 ft (2124 m)

    They said their finding suggests that these dwarf galaxies likely merged with other galaxies earlier in their history. The theory is consistent with computer simulations predicting that roughly half of the massive black holes in dwarf galaxies will be found wandering in the outskirts of their galaxies. Reines said:

    “This work has taught us that we must broaden our searches for massive black holes in dwarf galaxies beyond their centers to get a more complete understanding of the population and learn what mechanisms helped form the first massive black holes in the early universe.

    We hope that studying them and their galaxies will give us insights into how similar black holes in the early universe formed and then grew, through galactic mergers over billions of years, producing the supermassive black holes we see in larger galaxies today, with masses of many millions or billions of times that of the sun.”

    See the full article here .


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

    Stem Education Coalition

    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.

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    MSU provided

    Montana State University (MSU) is a public land-grant research university in Bozeman, Montana. It is the state’s largest university.[5] MSU offers baccalaureate degrees in 51 fields, master’s degrees in 41 fields, and doctoral degrees in 18 fields through its nine colleges. The university regularly reports annual research expenditures in excess of $100 million, including a record $138.8 million in 2019.

    More than 16,700 students attend MSU,[6] and the university faculty numbers, including department heads, are 602 full-time and 460 part-time.[7] The university’s main campus in Bozeman is home to KUSM television, KGLT radio, and the Museum of the Rockies. MSU provides outreach services to citizens and communities statewide through its agricultural experiment station and 60 county and reservation extension offices.

     
  • richardmitnick 1:38 pm on January 11, 2020 Permalink | Reply
    Tags: "Mexico’s Popocatépetl volcano had a spectacular eruption this week", , EarthSky, ,   

    From EarthSky: “Mexico’s Popocatépetl volcano had a spectacular eruption this week” 

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    From EarthSky

    January 9, 2020
    Deborah Byrd

    El Popo erupts! Well, it erupts often, but Thursday morning’s eruption – which happened at sunrise – was a beauty. El Popo is the nickname for Mexico’s most active volcano, Popocatépetl, near Mexico City. The eruption Thursday caused officials to issue a yellow alert.


    The active volcano Popocatépetl – just 43 miles (70 km) southeast of Mexico City, and visible from there when atmospheric conditions permit – erupted Thursday morning, January 9, 2020, spewing ash high into the air and oozing lava. Popocatépetl is affectionately called El Popo by Mexicans. It’s one of Mexico’s most active volcanoes. Officials say no one was hurt as a result of Thursday’s eruption. However, because it’s so near Mexico City, many cameras were trained on it. The sunrise light on the erupting volcano was a sight to see.

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    Spectacular eruption from one of Mexico’s most active volcanoes, Popocatepetl, Thursday morning. Image via @webcamsdemexico on Twitter.

    Officials said the eruption sent up a column of smoke about 2 miles (3 km) into the air, with a moderate ash content.

    NOAA’s GOES 16 satellite caught the eruption from space.

    NOAA GOES-16

    Popocatépetl has low- or medium-level eruptions often, and at times erupts more or less continuously. It has had more than 15 major eruptions since the arrival of the Spanish in 1519, according to Wikipedia.

    This morning’s eruption was a beauty, though! In part because of its location so near Mexico City, many cameras are trained on the volcano, and thus the January 9, 2020, eruption has been well documented so far, at this writing mostly on Twitter and YouTube.

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    A gorgeous shot of Popocatépetl on January 9, 2020, as the sun rose on its eruption. Image via @nuriapiera on Twitter.

    By the way, after Thursday’s eruption, official issued a “yellow phase 2.” The translation for this “AmarilloFase2” – explained in the tweet below – is as follows:

    “Preventive actions for the alert level #AmarilloFase2: Stay tuned for official information. Prepare important documents. Perform drills and know the location of temporary shelters. Develop a family plan for Civil Protection.”

    See the full article here .


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

    Stem Education Coalition

    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 8:30 am on January 7, 2020 Permalink | Reply
    Tags: "Magnitude 6.4 earthquake shakes Puerto Rico", , , , , EarthSky, , ,   

    From EarthSky: “Magnitude 6.4 earthquake shakes Puerto Rico” 

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    From EarthSky

    January 7, 2020
    Deborah Byrd

    USGS reports that the strong earthquake in Puerto Rico this morning was “widely felt.” Strong to very strong shaking occurred across parts of southern Puerto Rico closest to the event, and moderate shaking occurred across the rest of the island.

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    The January 7, 2020 6.4-magnitude earthquake in Puerto Rico was centered south of the island. Image via USGS.

    On January 7, 2020, a magnitude 6.4 earthquake struck Puerto Rico at 4:24 a.m. local time (08:24:26 UTC). Significant damage is possible. Over the past several weeks, hundreds of small earthquakes have occurred in the Puerto Rico region, beginning in earnest with a magnitude 4.7 earthquake late on December 28 and a magnitude 5.0 event a few hours later.

    The magnitude 6.4 earthquake on January 7 was widely felt. According to ShakeMap, strong to very strong shaking occurred across parts of southern Puerto Rico, closest to the event, and moderate shaking occurred across the rest of the island. The NOAA Tsunami Warning System states no tsunami warning or advisory. The USGS summary page on this earthquake includes an aftershock forecast. Aftershocks will continue near the mainshock.

    Since the magnitude 4.7 event on December 28, over 400 M 2+ earthquakes have occurred in this region, ten of which were magnitude 4+, including the January 7, 2020, 6.4 event and a January 6, 2020 5.8 quake. The preliminary location of the January 7 6.4 earthquake is within about 7.5 miles (12 km) of the January 6, 2020, magnitude 5.8 earthquake. The proximity of these events to Puerto Rico, and their shallow depth, mean that dozens of these events have been felt on land, though with the exception of the latest two earthquakes, the magnitude 6.4 and the magnitude 5.8, none are likely to have caused significant damage.

    The January 6 and 7, 2020, magnitude 5.8 and magnitude 6.4 earthquakes offshore of southwest Puerto Rico occurred as the result of oblique strike slip faulting at shallow depth. At the location of this event, the North America plate converges with the Caribbean plate at a rate of about 20 mm/yr towards the west-southwest. The location and style of faulting for the event is consistent with an intraplate tectonic setting within the upper crust of the Caribbean plate, rather than on the plate boundary between the two plates.

    Tectonics in Puerto Rico are dominated by the convergence between the North America and Caribbean plates, with the island being squeezed between the two.

    The tectonic plates of the world were mapped in 1996, USGS.

    To the north of Puerto Rico, North America subducts beneath the Caribbean plate along the Puerto Rico trench. To the south of the island, and south of today’s earthquake, Caribbean plate upper crust subducts beneath Puerto Rico at the Muertos Trough. The January 6 earthquake, and other recent nearby events, are occurring in the offshore deformation zone bound by the Punta Montalva Fault on land and the Guayanilla Canyon offshore.

    See the full article here .

    Earthquake Alert

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    Earthquake Alert

    Earthquake Network projectEarthquake Network is a research project which aims at developing and maintaining a crowdsourced smartphone-based earthquake warning system at a global level. Smartphones made available by the population are used to detect the earthquake waves using the on-board accelerometers. When an earthquake is detected, an earthquake warning is issued in order to alert the population not yet reached by the damaging waves of the earthquake.

    The project started on January 1, 2013 with the release of the homonymous Android application Earthquake Network. The author of the research project and developer of the smartphone application is Francesco Finazzi of the University of Bergamo, Italy.

    Get the app in the Google Play store.

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    Smartphone network spatial distribution (green and red dots) on December 4, 2015

    Meet The Quake-Catcher Network

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    ShakeAlert: An Earthquake Early Warning System for the West Coast of the United States

    The U. S. Geological Survey (USGS) along with a coalition of State and university partners is developing and testing an earthquake early warning (EEW) system called ShakeAlert for the west coast of the United States. Long term funding must be secured before the system can begin sending general public notifications, however, some limited pilot projects are active and more are being developed. The USGS has set the goal of beginning limited public notifications in 2018.

    Watch a video describing how ShakeAlert works in English or Spanish.

    The primary project partners include:

    United States Geological Survey
    California Governor’s Office of Emergency Services (CalOES)
    California Geological Survey
    California Institute of Technology
    University of California Berkeley
    University of Washington
    University of Oregon
    Gordon and Betty Moore Foundation

    The Earthquake Threat

    Earthquakes pose a national challenge because more than 143 million Americans live in areas of significant seismic risk across 39 states. Most of our Nation’s earthquake risk is concentrated on the West Coast of the United States. The Federal Emergency Management Agency (FEMA) has estimated the average annualized loss from earthquakes, nationwide, to be $5.3 billion, with 77 percent of that figure ($4.1 billion) coming from California, Washington, and Oregon, and 66 percent ($3.5 billion) from California alone. In the next 30 years, California has a 99.7 percent chance of a magnitude 6.7 or larger earthquake and the Pacific Northwest has a 10 percent chance of a magnitude 8 to 9 megathrust earthquake on the Cascadia subduction zone.

    Part of the Solution

    Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of the ShakeAlert system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave arrives, bringing the strong shaking that usually causes most of the damage.

    Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds. ShakeAlert can give enough time to slow trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.

    System Goal

    The USGS will issue public warnings of potentially damaging earthquakes and provide warning parameter data to government agencies and private users on a region-by-region basis, as soon as the ShakeAlert system, its products, and its parametric data meet minimum quality and reliability standards in those geographic regions. The USGS has set the goal of beginning limited public notifications in 2018. Product availability will expand geographically via ANSS regional seismic networks, such that ShakeAlert products and warnings become available for all regions with dense seismic instrumentation.

    Current Status

    The West Coast ShakeAlert system is being developed by expanding and upgrading the infrastructure of regional seismic networks that are part of the Advanced National Seismic System (ANSS); the California Integrated Seismic Network (CISN) is made up of the Southern California Seismic Network, SCSN) and the Northern California Seismic System, NCSS and the Pacific Northwest Seismic Network (PNSN). This enables the USGS and ANSS to leverage their substantial investment in sensor networks, data telemetry systems, data processing centers, and software for earthquake monitoring activities residing in these network centers. The ShakeAlert system has been sending live alerts to “beta” users in California since January of 2012 and in the Pacific Northwest since February of 2015.

    In February of 2016 the USGS, along with its partners, rolled-out the next-generation ShakeAlert early warning test system in California joined by Oregon and Washington in April 2017. This West Coast-wide “production prototype” has been designed for redundant, reliable operations. The system includes geographically distributed servers, and allows for automatic fail-over if connection is lost.

    This next-generation system will not yet support public warnings but does allow selected early adopters to develop and deploy pilot implementations that take protective actions triggered by the ShakeAlert notifications in areas with sufficient sensor coverage.

    Authorities

    The USGS will develop and operate the ShakeAlert system, and issue public notifications under collaborative authorities with FEMA, as part of the National Earthquake Hazard Reduction Program, as enacted by the Earthquake Hazards Reduction Act of 1977, 42 U.S.C. §§ 7704 SEC. 2.

    For More Information

    Robert de Groot, ShakeAlert National Coordinator for Communication, Education, and Outreach
    rdegroot@usgs.gov
    626-583-7225

    Learn more about EEW Research

    ShakeAlert Fact Sheet

    ShakeAlert Implementation Plan


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

    Stem Education Coalition

    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 10:08 am on December 18, 2019 Permalink | Reply
    Tags: EarthSky, , , Pulsar J0030,   

    From NASA via EarthSky: “Scientists map a pulsar for the 1st time” 

    From NASA

    via

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    EarthSky

    Using a revolutionary X-ray telescope aboard the International Space Station, scientists have finally created the 1st pulsar surface “map.” It shows odd hot spots and suggests that pulsar magnetic fields are more complicated than anyone had assumed.

    NASA/NICER on the ISS

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    New “map” of hotspots on pulsar J0030, from observations from July 2017 to December 2018. Image via Goddard Space Flight Center/ NASA.

    Pulsars – the extremely dense but tiny remnants of exploded stars – have been known for decades, but remain one of the most enigmatic phenomena in the known universe. They’re not easy to study, in part due to their immense distances. Now, using a special X-ray telescope launched to the International Space Station (ISS) in 2017, scientists have been able to map a pulsar and take precise measurements of its size and mass, for the first time. These momentous findings also include odd hot spots on the pulsar’s surface.

    NASA announced the findings on December 12, 2019, and these results have been published in a series of new peer-reviewed papers in a special issue of The Astrophysical Journal Letters.

    The study focuses on a pulsar called J0030+0451 (J0030), in an isolated region of space 1,100 light-years away in the direction of the constellation Pisces.

    Astrophysicist Paul Hertz, at NASA headquarters, said in a statement that, from its perch above Earth aboard ISS, NASA’s NICER telescope – which stands for Neutron star Interior Composition Explorer – is revolutionizing our understanding of pulsars:

    “Pulsars were discovered more than 50 years ago as beacons of stars that have collapsed into dense cores, behaving unlike anything we see on Earth. With NICER we can probe the nature of these dense remnants in ways that seemed impossible until now.”

    Dame Susan Jocelyn Bell Burnell, discovered pulsars with radio astronomy. Jocelyn Bell at the Mullard Radio Astronomy Observatory, Cambridge University, taken for the Daily Herald newspaper in 1968. Denied the Nobel.

    The researchers – two groups of scientists – used NICER observations from July 2017 to December 2018, and came up with similar results for the size and mass of the pulsar, as well as hot spots on its surface.

    With the help of computer simulations, NICER found three million-degree hot spots on the pulsar, all in its southern hemisphere, but the spots didn’t look like what textbooks had predicted. One spot was small and circular, while another was longer and crescent-shaped. The third spot, a bit cooler, was slightly askew of the pulsar’s south rotational pole. Previous models had suggested that the locations and shapes of the spots would vary more.

    This is the first time that such surface features have been positively identified on a pulsar. The findings indicate that pulsar magnetic fields are more complicated than the traditional two-pole model had implied.

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    Simulation of a possible quadrupole magnetic field configuration – 2 pairs of oppositely charged poles – for a pulsar with hot spots only in its southern hemisphere. The new pulsar map suggests that pulsar magnetic fields are more complicated than anyone knew. Image via Goddard Space Flight Center/ NASA.

    NICER was also able to determine a pulsar’s size and mass much more accurately than ever before.

    One of the research teams, led by Thomas Riley, a doctoral student in computational astrophysics, and his supervisor Anna Watts, a professor of astrophysics at the University of Amsterdam, found that the pulsar is about 1.3 times the sun’s mass and 15.8 miles (25.4 km) across.

    The second team, led by Cole Miller, an astronomy professor at the University of Maryland, came up with very similar results: 1.4 times the sun’s mass and about 16.2 miles (26 km) wide. Riley said:

    “When we first started working on J0030, our understanding of how to simulate pulsars was incomplete, and it still is. But thanks to NICER’s detailed data, open-source tools, high-performance computers and great teamwork, we now have a framework for developing more realistic models of these objects.”

    Miller said:

    “NICER’s unparalleled X-ray measurements allowed us to make the most precise and reliable calculations of a pulsar’s size to date, with an uncertainty of less than 10%. The whole NICER team has made an important contribution to fundamental physics that is impossible to probe in terrestrial laboratories.”

    NICER is so accurate it can measure the arrival of each X-ray from a pulsar to better than a hundred nanoseconds (one nanosecond is a billionth of a second). That precision is about 20 times greater than any previously available.

    Pulsars are the rapidly spinning, dense and tiny remnants of stars that exploded in a supernova. They are one type of neutron star and can spin up to hundreds of times per second, sweeping beams of radiation energy toward us with every rotation. J0030 revolves 205 times per second.

    Pulsars are unimaginably dense; their gravity actually warps nearby space-time, the “fabric” of the universe as described by Einstein’s general theory of relativity. Their rotations are so regular, that it was first thought that they might be evidence of extraterrestrial intelligence, until it was determined they were a natural phenomenon.

    Scientists now want to determine the masses and sizes of several more pulsars besides J0030. By doing so, they can better understand the state of matter in the cores of such neutron stars. The pressures and densities are well beyond anything that can be replicated in laboratories on Earth. According to Zaven Arzoumanian, NICER science lead at NASA’s Goddard Space Flight Center:

    “It’s remarkable, and also very reassuring, that the two teams achieved such similar sizes, masses and hot spot patterns for J0030 using different modeling approaches. It tells us NICER is on the right path to help us answer an enduring question in astrophysics: What form does matter take in the ultra-dense cores of neutron stars?”

    The new findings are a breakthrough in pulsar and neutron star research, and will help scientists learn more about these very mysterious objects. For more, check out the video below.

    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 National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

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

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

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

     
  • richardmitnick 10:44 am on December 17, 2019 Permalink | Reply
    Tags: "Water on giant exoplanets both common and scarce", , , , , EarthSky, University of Cambridge Institute of Astronomy, Water – an essential ingredient for life   

    From University of Cambridge Institute of Astronomy via EarthSky : “Water on giant exoplanets both common and scarce” 

    U Cambridge bloc

    From University of Cambridge – Institute of Astronomy

    via

    1

    EarthSky

    December 17, 2019
    Paul Scott Anderson

    1
    Artist’s concept of a gas giant exoplanet orbiting close to its star. The new study suggests water vapor is common on such worlds, but maybe in lesser amounts than thought. Image via Amanda Smith/ University of Cambridge.

    A new study of the atmospheres of known giant exoplanets suggests that water – an essential ingredient for life – may be common on other worlds in our Milky Way galaxy. At the same, there may be less of it than astronomers once expected.

    Water – needed for life as we know it – has turned out to be common in our solar system. Besides Earth, of course, there are moons in the outer solar system with oceans beneath their icy surfaces. Ice can be found almost everywhere in our neighborhood of space, even on the moon and Mercury! But what about in other solar systems? A new study, led by researchers from the University of Cambridge, suggests that water may be at the same time both plentiful and scarce, depending on the type of planets involved.

    The new findings were announced by Cambridge on December 11, 2019, and the peer-reviewed paper was published in The Astrophysical Journal Letters on the same day.

    The researchers studied atmospheric data from 19 known exoplanets to learn more about their chemical and thermal properties. These planets ranged from mini-Neptunes (nearly 10 Earth masses) to super-Jupiters (over 600 Earth masses). Temperatures on these worlds range from 20 degrees Celsius (about 70 degrees Fahrenheit) to over 2,000 degrees Celsius (3,600 F). These planets are similar to the gas and ice giants in our solar system, but they orbit a variety of different types of stars. Study leader Nikku Madhusudhan, of the Institute of Astronomy at Cambridge, said:

    “We are seeing the first signs of chemical patterns in extra-terrestrial worlds, and we’re seeing just how diverse they can be in terms of their chemical compositions.”

    2
    Artist’s concept of a mini-Neptune exoplanet. Water vapor was recently detected in the atmosphere of a world such as this. Image via ESA/ Hubble/ M. Kornmesser/ Bad Astronomy.

    The findings are challenging current theories on planetary formation.

    Both ground and space-based telescopes were used to gather spectrographic data from the planets, including the Hubble Space Telescope, the Spitzer Space Telescope, the Very Large Telescope in Chile and the Gran Telescopio Canarias in Spain. The researchers were able to estimate the chemical abundances of the atmospheres of all the planets.

    NASA/ESA Hubble Telescope

    NASA/Spitzer Infrared Telescope

    ESO VLT at Cerro Paranal in the Atacama Desert, •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).
    elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo,

    Gran Telescopio Canarias at the Roque de los Muchachos Observatory on the island of La Palma, in the Canaries, Spain, sited on a volcanic peak 2,267 metres (7,438 ft) above sea level

    Based on what we know about the giant planets in our own solar system, these kinds of exoplanets were predicted to have similar high abundances of certain elements such as hydrogen, oxygen and water. So what did they find?

    The results showed that 14 of the planets had an abundance of water vapor, as well as an abundance of sodium and potassium in six planets each. This suggests that there is a depletion of oxygen relative to the other elements and that the planets may have evolved with little accretion of ice. As Madhusudhan noted:

    “It is incredible to see such low water abundances in the atmospheres of a broad range of planets orbiting a variety of stars.”

    3
    Comparison of exoplanet Kepler-186f with Earth (artist’s concept). Some of these Earth-sized rocky worlds should also be able to have liquid water on their surfaces, although that research was not part of this particular study, which focused on giant gas and ice planets. Image via NASA Ames/ SETI Institute/ JPL-Caltech/ Ars Technica.

    This means that exoplanets can be more diverse than previously thought in terms of atmospheric composition and water content, which challenges several theoretical models of planet formation. Different chemical elements can no longer just be assumed to be equally abundant in planetary atmospheres.

    It’s not easy measuring how much water there is in the atmospheres of planets so far away, but it can even be challenging for planets much closer to home. Jupiter is a prime example of this. According to Luis Welbanks, lead author of the study:

    “Measuring the abundances of these chemicals in exoplanetary atmospheres is something extraordinary, considering that we have not been able to do the same for giant planets in our solar system yet, including Jupiter, our nearest gas giant neighbor.

    Since Jupiter is so cold, any water vapor in its atmosphere would be condensed, making it difficult to measure. If the water abundance in Jupiter were found to be plentiful as predicted, it would imply that it formed in a different way to the exoplanets we looked at in the current study.”

    4
    Determining the amount of water vapor in the atmospheres of the giant planets even in our own solar system can be challenging. This is Jupiter as seen by the Juno spacecraft on April 1, 2018. Image via NASA/ JPL-Caltech/ SwRI/ MSSS/ Gerald Eichstad/ Sean Doran/ Newsweek.

    As already mentioned, the sample size of planets in the study is quite small, so researchers want to expand on it in the future. Madhusudhan commented:

    “We look forward to increasing the size of our planet sample in future studies. Inevitably, we expect to find outliers to the current trends as well as measurements of other chemicals.”

    It should also be noted that this current study did not include smaller rocky super-Earth or Earth-sized planets, which are now known to be quite common in our galaxy. Those are the kinds of worlds where the amount of water would have the most consequence in terms of the potential habitability of a planet.

    As Madhusudhan said:

    “Given that water is a key ingredient to our notion of habitability on Earth, it is important to know how much water can be found in planetary systems beyond our own.”

    While this study may be limited regarding the types of exoplanets known to exist, it provides an important insight into how much water could be expected to be discovered among a large population of such worlds. This will help scientists better understand how these planets formed, and perhaps provide clues as to how many potentially habitable planets there may be as well, when combined with additional future studies of rocky worlds more similar to Earth.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    U Cambridge Campus

    The IoA is part of the Faculty of Physics and Chemistry within the School of the Physical Sciences of The University of Cambridge.

    Cambridge Institute of Astronomy

    The Institute of Astronomy (IoA) came into being in 1972 by the amalgamation of three institutions which had developed on the site. These were the Cambridge University Observatory which was established in 1823, the Solar Physics Observatory (1912) and the Institute of Theoretical Astronomy (1967).

    The IoA is a department of the University of Cambridge and is engaged in teaching and research in the fields of theoretical and observational Astronomy. A wide class of theoretical problems are studied, ranging from models of quasars and of the evolution of the universe, through theories of the formation and evolution of galaxies and stars, X-ray sources and black holes.

    Much observational work centres around the use by staff of large telescopes abroad and in space to study quasars, galaxies and the chemical constitution of stars. A programme on the velocities of stars is conducted using the 36-inch telescope in Cambridge. Instrumentation development is also an important area of activity, involving charge coupled devices and detector arrays for rapid recording of very faint light and the design and construction of novel spectrographs.

    The Institute comprises about 88 postdoctoral staff, 45 graduate students and 26 support staff. There are close links with the Cavendish Astrophysics Group (formerly the Mullard Radio Astronomy Observatory) as well as with the Department of Applied Mathematics and Theoretical Physics, all of which are conducting complementary research programmes here in Cambridge.

    The University of Cambridge (abbreviated as Cantab in post-nominal letters) is a collegiate public research university in Cambridge, England. Founded in 1209, Cambridge is the second-oldest university in the English-speaking world and the world’s fourth-oldest surviving university. It grew out of an association of scholars who left the University of Oxford after a dispute with townsfolk. The two ancient universities share many common features and are often jointly referred to as “Oxbridge”.

    Cambridge is formed from a variety of institutions which include 31 constituent colleges and over 100 academic departments organised into six schools. The university occupies buildings throughout the town, many of which are of historical importance. The colleges are self-governing institutions founded as integral parts of the university. In the year ended 31 July 2014, the university had a total income of £1.51 billion, of which £371 million was from research grants and contracts. The central university and colleges have a combined endowment of around £4.9 billion, the largest of any university outside the United States. Cambridge is a member of many associations and forms part of the “golden triangle” of leading English universities and Cambridge University Health Partners, an academic health science centre. The university is closely linked with the development of the high-tech business cluster known as “Silicon Fen”.

     
  • richardmitnick 10:31 am on December 15, 2019 Permalink | Reply
    Tags: "A second black hole at our galaxy’s center?", , , , , , EarthSky, , , ,   

    From UCLA via EarthSky: “A second black hole at our galaxy’s center?” 

    UCLA bloc

    From UCLA

    via

    1

    EarthSky

    December 15, 2019
    Smadar Naoz, University of California, Los Angeles

    1
    Artist’s concept of 2 black holes entwined in a gravitational tango. Image via NASA/ JPL-Caltech/ SwRI/ MSSS/ Christopher Go.

    There’s a supermassive black hole – 4 million times our sun’s mass – in the center of our Milky Way galaxy. Astronomers who’ve measured star movements near this central black hole are now saying there might be a 2nd companion black hole near it.

    Do supermassive black holes have friends? The nature of galaxy formation suggests that the answer is yes, and in fact, pairs of supermassive black holes should be common in the universe.

    I am an astrophysicist and am interested in a wide range of theoretical problems in astrophysics, from the formation of the very first galaxies to the gravitational interactions of black holes, stars and even planets. Black holes are intriguing systems, and supermassive black holes and the dense stellar environments that surround them represent one of the most extreme places in our universe.

    The supermassive black hole that lurks at the center of our galaxy, called Sgr A*, has a mass of about 4 million times that of our sun.

    SgrA* NASA/Chandra supermassive black hole at the center of the Milky Way, X-ray image of the center of our galaxy, where the supermassive black hole Sagittarius A* resides. Image via X-ray: NASA/UMass/D.Wang et al., IR: NASA/STScI.

    SGR A* , the supermassive black hole at the center of the Milky Way. NASA’s Chandra X-Ray Observatory

    A black hole is a place in space where gravity is so strong that neither particles or light can escape from it. Surrounding Sgr A* is a dense cluster of stars. Precise measurements of the orbits of these stars allowed astronomers to confirm the existence of this supermassive black hole and to measure its mass. For more than 20 years, scientists have been monitoring the orbits of these stars around the supermassive black hole. Based on what we’ve seen, my colleagues and I show that if there is a friend there, it might be a second black hole nearby that is at least 100,000 times the mass of the sun.

    Supermassive black holes and their friends

    Almost every galaxy, including our Milky Way, has a supermassive black hole at its heart, with masses of millions to billions of times the mass of the sun.

    Milky Way NASA/JPL-Caltech /ESO R. Hurt. The bar is visible in this image

    Astronomers are still studying why the heart of galaxies often hosts a supermassive black hole. One popular idea connects to the possibility that supermassive holes have friends.

    To understand this idea, we need to go back to when the universe was about 100 million years old, to the era of the very first galaxies. They were much smaller than today’s galaxies, about 10,000 or more times less massive than the Milky Way. Within these early galaxies the very first stars that died created black holes, of about tens to thousand the mass of the sun. These black holes sank to the center of gravity, the heart of their host galaxy. Since galaxies evolve by merging and colliding with one another, collisions between galaxies will result in supermassive black hole pairs – the key part of this story.

    Milkdromeda -Andromeda on the left-Earth’s night sky in 3.75 billion years-NASA

    The black holes then collide and grow in size as well. A black hole that is more than a million times the mass of our sun is considered supermassive.

    If indeed the supermassive black hole has a friend revolving around it in close orbit, the center of the galaxy is locked in a complex dance. The partners’ gravitational tugs will also exert its own pull on the nearby stars disturbing their orbits. The two supermassive black holes are orbiting each other, and at the same time, each is exerting its own pull on the stars around it.

    The gravitational forces from the black holes pull on these stars and make them change their orbit; in other words, after one revolution around the supermassive black hole pair, a star will not go exactly back to the point at which it began.

    Using our understanding of the gravitational interaction between the possible supermassive black hole pair and the surrounding stars, astronomers can predict what will happen to stars. Astrophysicists like my colleagues and me can compare our predictions to observations, and then can determine the possible orbits of stars and figure out whether the supermassive black hole has a companion that is exerting gravitational influence.

    Using a well-studied star, called S0-2, which orbits the supermassive black hole that lies at the center of the galaxy every 16 years, we can already rule out the idea that there is a second supermassive black hole with mass above 100,000 times the mass of the sun and farther than about 200 times the distance between the sun and the Earth.

    Star S0-2 Andrea Ghez Keck/UCLA Galactic Center Group at SGR A*, the supermassive black hole at the center of the milky way

    If there was such a companion, then I and my colleagues would have detected its effects on the orbit of SO-2.

    But that doesn’t mean that a smaller companion black hole cannot still hide there. Such an object may not alter the orbit of SO-2 in a way we can easily measure.

    The physics of supermassive black holes

    Supermassive black holes have gotten a lot of attention lately. In particular, the recent image of such a giant at the center of the galaxy Messier 87 opened a new window to understanding the physics behind black holes.

    The first image of a black hole.This is the supermassive black hole at the center of the galaxy Messier 87. Image via JPL/ Event Horizon Telescope Collaboration.

    The proximity of the Milky Way’s galactic center – a mere 24,000 light-years away – provides a unique laboratory for addressing issues in the fundamental physics of supermassive black holes. For example, astrophysicists like myself would like to understand their impact on the central regions of galaxies and their role in galaxy formation and evolution. The detection of a pair of supermassive black holes in the galactic center would indicate that the Milky Way merged with another, possibly small, galaxy at some time in the past.

    That’s not all that monitoring the surrounding stars can tell us. Measurements of the star S0-2 allowed scientists to carry out a unique test of Einstein’s general theory of relativity. In May 2018, S0-2 zoomed past the supermassive black hole at a distance of only about 130 times the Earth’s distance from the sun. According to Einstein’s theory, the wavelength of light emitted by the star should stretch as it climbs from the deep gravitational well of the supermassive black hole.

    The stretching wavelength that Einstein predicted – which makes the star appear redder – was detected and proves that the theory of general relativity accurately describes the physics in this extreme gravitational zone. I am eagerly awaiting the second closest approach of S0-2, which will occur in about 16 years, because astrophysicists like myself will be able to test more of Einstein’s predictions about general relativity, including the change of the orientation of the stars’ elongated orbit. But if the supermassive black hole has a partner, this could alter the expected result.

    3
    This NASA/ESA Hubble Space Telescope image show’s the result of a galactic collision between two good-sized galaxies. This new jumble of stars is slowly evolving to become a giant elliptical galaxy. Image via ESA/ Hubble/ NASA/ Judy Schmidt

    NASA/ESA Hubble Telescope

    Finally, if there are two massive black holes orbiting each other at the galactic center, as my team suggests is possible, they will emit gravitational waves.

    Gravitational waves. Credit: MPI for Gravitational Physics/Werner Benger

    Since 2015, the LIGO-Virgo observatories have been detecting gravitational wave radiation from merging stellar-mass black holes and neutron stars.

    MIT /Caltech Advanced aLigo


    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    These groundbreaking detections have opened a new way for scientists to sense the universe.

    Any waves emitted by our hypothetical black hole pair will be at low frequencies, too low for the LIGO-Virgo detectors to sense. But a planned space-based detector known as LISA may be able to detect these waves, which will help astrophysicists figure out whether our galactic center black hole is alone or has a partner.

    ESA/NASA eLISA


    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

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 1:36 pm on December 10, 2019 Permalink | Reply
    Tags: "Meet the microorganism that likes to eat meteorites", , , , , , EarthSky, For this study the researchers ran tests on material from a meteorite labeled Northwest Africa 1172 (NWA 1172)., , Redox is is a type of chemical reaction in which the oxidation states of atoms are changed and is common in biological processes., The microbe M. sedula,   

    From University of Vienna via EarthSky: “Meet the microorganism that likes to eat meteorites” 

    From University of Vienna

    via

    1

    EarthSky

    December 10, 2019
    Paul Scott Anderson

    At least one type of microbe on Earth not only likes to eat meteorites but actually prefers them as a food source, according to a new international scientific study.

    1
    Meteorite dust fragments colonized and bioprocessed by the microbe M. sedula. Image via Tetyana Milojevic/ Universität Wien.

    You’ve gotta eat to live. That’s a truism not just for humans but for other lifeforms, including microbes. Now an international team of scientists has announced a new study, showing that at least one type of earthly bacteria has a fondness for extraterrestrial food: meteorites, or rocks from space. These microbes even seem to prefer space rocks to their usual earthly fare of earthly rocks.

    The intriguing peer-reviewed results were published in Nature Scientific Reports on December 2, 2019.

    Astrobiologist Tetyana Milojevic of the University of Vienna in Austria led the research, which demonstrated that an ancient single-celled bacteria known as Metallosphaera sedula (M. sedula) can not only process material in meteorites for food, but will even colonize meteorites faster than earthly rocks.

    M. sedula belong to a family of bacteria known as lithotrophs; that is, they derive their energy from inorganic sources. The term “lithotroph” was created from the Greek terms ‘lithos’ (rock) and ‘troph’ (consumer), meaning “eaters of rock.”

    For this study, the researchers ran tests on material from a meteorite labeled Northwest Africa 1172 (NWA 1172). They found that the microbes colonized the material much more quickly than they would terrestrial material.

    3
    Graphic showing the ingestion of inorganic material by the microbe M. sedula in the meteorite NWA 1172. Image via Tetyana Milojevic/ Universität Wien.

    As Milojevic said in a statement:

    “Meteorite-fitness seems to be more beneficial for this ancient microorganism than a diet on terrestrial mineral sources. NWA 1172 is a multimetallic material, which may provide much more trace metals to facilitate metabolic activity and microbial growth. Moreover, the porosity of NWA 1172 might also reflect the superior growth rate of M. sedula.”

    This is certainly interesting, suggesting that M. sedula actually prefers the material coming from space over its local, home-grown, earthly food sources.

    4
    Scanning electron microscope image of meteorite NWA 1172, showing colonization of M. sedula microbes. Image via Tetyana Milojevic/ Universität Wien/ Daily Mail.

    So how did the scientists make these findings?

    “They examined the meteorite-microbial interface at nanometer scale – one billionth of a meter – and traced how the material was consumed, investigating the iron redox behavior. Redox is is a type of chemical reaction in which the oxidation states of atoms are changed, and is common in biological processes. By combining several analytical spectroscopy techniques with transmission electron microscopy, they found a set of biogeochemical fingerprints left upon M. sedula growth on the meteorite. As Milojevic explained:

    Our investigations validate the ability of M. sedula to perform the biotransformation of meteorite minerals, unravel microbial fingerprints left on meteorite material, and provide the next step towards an understanding of meteorite biogeochemistry.”

    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 University of Vienna (German: Universität Wien) is a public university located in Vienna, Austria. It was founded by Duke Rudolph IV in 1365 and is one of the oldest universities in the German-speaking world. With its long and rich history, the University of Vienna has developed into one of the largest universities in Europe, and also one of the most renowned, especially in the Humanities. It is associated with 15 Nobel prize winners and has been the academic home to a large number of scholars of historical as well as of academic importance.

     
  • richardmitnick 12:20 pm on December 2, 2019 Permalink | Reply
    Tags: "Thousands of exoplanets may orbit supermassive black holes", , , , , EarthSky, Kagoshima University,   

    From National Astronomical Observatory of Japan via EarthSky: “Thousands of exoplanets may orbit supermassive black holes” 

    NAOJ

    From National Astronomical Observatory of Japan

    via

    1

    EarthSky

    December 1, 2019
    Paul Scott Anderson

    It sounds unbelievable, but a new study from Kagoshima University and the National Astronomical Observatory of Japan says that exoplanets – thousands of them – could be orbiting supermassive black holes.

    1
    Artist’s concept of a black hole with its bright surrounding disk of gas and dust – and jets extending from its poles – plus many orbiting planets. Image via Kagoshima University /NAOJ.

    Exoplanets – worlds orbiting other stars – are common, with billions estimated to exist in our galaxy alone. They’ve been found around all sorts of stars, including sunlike stars, red dwarfs and even pulsars. There also seem to be rogue planets, which don’t orbit any stars, but instead just wander lonely though interstellar space. And now a new study suggests there might be yet another entirely new class of planets, orbiting supermassive black holes.

    The intriguing findings were announced by researchers at Kagoshima University and the National Astronomical Observatory of Japan on November 25, 2019. The new peer-reviewed study was published in The Astrophysical Journal on November 26, 2019.

    It sounds like something out of science fiction, but according to the researchers, black holes that have massive disks of dust and gas surrounding them (called circumnuclear disks), just like protoplanetary disks around young stars, could produce planets – a lot of them – just like the disks around stars. Supermassive black holes (SMBHs) could have thousands of planets orbiting them, the researchers say. Although orbiting the black hole, the planets would likely be a long way from the black hole itself, around 10 light-years. From the paper:

    “As a natural consequence of the elementary processes of dust growth, we discovered that a new class of planets can be formed around supermassive black holes (SMBHs). We investigated a growth path from submicron sized icy dust monomers to Earth-sized bodies outside the “snow line,” located several parsecs from SMBHs in low luminosity active galactic nuclei (AGNs).”

    This computer-simulated image of a supermassive black hole at the core of a galaxy. Credit NASA, ESA, and D. Coe, J. Anderson

    As Keiichi Wada, a professor at Kagoshima University, said in a statement:

    “With the right conditions, planets could be formed even in harsh environments, such as around a black hole.”

    Eiichiro Kokubo, a professor at the National Astronomical Observatory of Japan, said:

    “Our calculations show that tens of thousands of planets with 10 times the mass of the Earth could be formed around 10 light-years from a black hole. Around black holes there might exist planetary systems of astonishing scale.”

    3
    The first-ever photo of a black hole, in the center of galaxy Messier 87, taken by the Event Horizon Telescope. The black hole is a staggering 6.5 billion times more massive than the sun. The bright ring is light bent by the black hole’s gravity. Image via Event Horizon Telescope Collaboration/NASA.

    The amount of dust surrounding a supermassive black hole can be enormous, as much as a hundred thousand times the mass of our sun, or about a billion times more than in a typical protoplanetary disk.

    How would planets form in such an environment?

    In a disk around a black hole, the dust is so dense that it blocks radiation from the black hole itself. This allows temperatures cool enough for icy dust grains to stick together and aggregate, just like they do in protoplanetary disks around stars. The researchers calculated that planets could form in several hundred million years in this manner around black holes.

    Such black hole planets can’t yet be directly detected with current telescopes, but the findings open up a tentative and fascinating new field of study. From the paper:

    “Observing planets around SMBHs should be challenging. The standard techniques to detect exoplanets around stars, i.e., Doppler spectroscopy, transit photometry, gravitational microlensing, or direct imaging are hopeless. Photometry by a hard X-ray interferometer in space might be a possible solution, but the occultation of the accretion disk by the “planets” would be hard to distinguish from the intrinsic time variability of AGNs. The other, indirect way is detecting spectral changes in the millimeter-wavelength due to opacity variation associated with the dust growth as used in the protoplanetary disk.”

    It’s already known that stars can also orbit black holes, such as the ones orbiting the supermassive black hole – called Sagittarius A* – at the center of our galaxy.

    SgrA* NASA/Chandra supermassive black hole at the center of the Milky Way, X-ray image of the center of our galaxy, where the supermassive black hole Sagittarius A* resides. Image via X-ray: NASA/UMass/D.Wang et al., IR: NASA/STScI.

    SGR A* , the supermassive black hole at the center of the Milky Way. NASA’s Chandra X-Ray Observatory

    Black holes aren’t really holes, but objects that have gravitational pulls so strong that nothing, not even light, can escape. The “surface” of a black hole, called the event horizon, is the boundary where the velocity needed to escape exceeds the speed of light. Matter and radiation fall in, but they can’t get out.

    There are two main classes of black holes. Stellar-mass black holes are three to dozens of times the sun’s mass. The supermassive black holes already discussed are 100,000 to billions of solar masses, and are located in the centers of most large galaxies, including ours. There may also be intermediate-mass black holes, about 100 to more than 10,000 solar masses. There are candidates, but they have not yet been confirmed to exist.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    NAOJ

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

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


    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array
    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

     
  • richardmitnick 10:16 am on November 10, 2019 Permalink | Reply
    Tags: "Did ancient Earth life escape our solar system?", , , , , EarthSky, ,   

    From Harvard Astronomy and EarthSky: “Did ancient Earth life escape our solar system?” 

    Harvard Astronomy Banner
    From Harvard Astronomy

    and

    1

    EarthSky

    November 10, 2019
    Paul Scott Anderson

    You’ve heard of panspermia, the idea that life exists throughout space and was carried to Earth by comets? What if the reverse occurred, with microbes on Earth ejected into space by asteroid impacts, escaping into the solar system billions of years ago?

    1
    Bacteria-like fossilized structures in the Martian meteorite ALH84001. Image via NASA/Wikimedia/Scientific American.

    Panspermia is the theory that asteroids, meteors or comets can carry microorganisms from one planetary system to another, and that such a process – perhaps microbes coming from Mars – may have helped life first develop on Earth. But could the reverse also be possible? Could microbial life be launched from Earth by asteroid impacts? Could that earthly life then end up leaving our solar system altogether? A new research paper by theoretical physicist Abraham (Avi) Loeb at Harvard University suggests that there could have been many such events over the lifetime of the Earth so far. He also just wrote a thought-provoking opinion article in Scientific American discussing this fascinating possibility.

    From the paper:

    “Exporting terrestrial life out of the solar system requires a process that both embeds microbes in boulders and ejects those boulders out of the solar system. We explore the possibility that Earth-grazing long-period comets and interstellar objects could export life from Earth by collecting microbes from the atmosphere and receiving a gravitational slingshot effect from the Earth. We estimate the total number of exportation events over the lifetime of the Earth to be about 1-10 for long-period comets and about 1-50 for interstellar objects. If life existed above an altitude of 100 km [62 miles], then the number is dramatically increased up to about 100,000 exportation events over Earth’s lifetime.”

    2
    The panspermia theory says that microbes could be transported through the galaxy in asteroids, meteors or comets, and may even help explain the beginnings of life on Earth. A new study by Abraham (Avi) Loeb says that it is also possible that microscopic life could have been blasted off the Earth multiple times in the ancient past, potentially even escaping our solar system. Image via Astrobiology at NASA.

    The idea that earthly life could be exported to other places in the solar system or even beyond is a fascinating one. But has it really happened?

    As Loeb noted, in most cases asteroid impacts wouldn’t be able to send rocks outside the solar system, but some of them could still make that journey with the help of other planets:

    “Most asteroid impacts are not powerful enough to eject terrestrial rocks with enough speed to leave the solar system. But many solar system bodies spend most of their time in the Oort Cloud, a sort of comet nursery that hovers, loosely bound to the sun, at distances up to 100,000 times farther out than Earth. Some of these bodies appear episodically as long-period comets with eccentric orbits that bring them close to the sun, where they can get gravitationally kicked by planets all the way out of the solar system, like a ball running through a pinball machine.”

    3
    Bacillus subtilis is one type of microorganism that could survive being ejected into space by an asteroid impact. Image via Wickham Laboratories.

    As well as microbes in rocks or soil, there are colonies of microbes in the atmosphere itself, at altitudes of about of 30 to 48 miles (48 to 77 kilometers). They could be “scooped up” by asteroids passing very close to Earth, but not impacting. This could even happen with asteroids that originated from beyond the solar system.

    As Loeb also noted, microbes would be much better suited for surviving being violently ejected into space inside a chunk of rock:

    “It is well known that fighter pilots can barely survive maneuvers with accelerations exceeding 10 gs, where g is the gravitational acceleration that binds us to Earth. But Earth-grazing objects would scoop microbes at accelerations of millions of gs. Could they survive the jolt? Possibly! Microbes and other tiny organisms such as Bacillus subtilis, Caenorhabditis elegans, Deinococcus radiodurans, Escherichia coli and Paracoccus denitrificans have been shown to live through accelerations just one order of magnitude smaller. As it turns out, these mini astronauts are far better suited for taking a space ride than our very best human pilots.”

    So, could Earth have spread life to other worlds? If any microbes from Earth ever did make this journey billions of years ago, could they have survived anywhere else in the solar system if they landed on another planet or moon? Not too likely, apart from maybe Mars (depending on how habitable it was at the time) or ice/ocean moons like Europa or Enceladus. But even on those moons, any microbes would just get dumped on the airless surfaces covered in ice. It’s doubtful that they could make their way down to the oceans below through the ice crusts unless perhaps they fell into a deep crack connected to water vapor geysers, as on Enceladus.

    7
    Theoretical physicist Abraham (Avi) Loeb. Image via Lane Turner/The Boston Globe via Getty Images/Harvard University.

    If any life is ever discovered in the oceans of Europa or Enceladus, it’s more likely that it evolved there on its own. Also, if any microbes did make it out of the solar system completely, they would be traveling for millions or billions of years before encountering any other exoplanets or exomoons.

    While it hasn’t been proven yet that life from Earth has previously traveled throughout – and perhaps even out of – the solar system, it is, according to Loeb, certainly a very interesting possibility.

    Bottom line: A new paper by theoretical physicist Abraham (Avi) Loeb makes the case that microbes could have been ejected into space by asteroid impacts billions of years ago, in a reverse kind of panspermia.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    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.

    Harvard Astronomy

    Although the Department of Astronomy came into existence in 1931, the first chair, Donald Menzel, wasn’t appointed until 1945. Menzel was subsequently named Director of the Harvard Observatory in 1952 and immediately set about to encourage the Smithsonian Astrophysical Observatory (SAO) to relocate to Cambridge, which it did in 1955.

    Fred Whipple was appointed as Professor of Astronomy in 1950 and was the department’s second chair. In 1955 he assumed directorship of the SAO in its new location. In 1956 Cecilia Payne-Gaposchkin became the first woman to be promoted to full professor from within the Faculty of Arts and Sciences and soon after was appointed the third chair, making her the first woman to head a department at Harvard University.

    George Field formalized the interactions between the two organizations by creating an administrative umbrella organization named the Harvard-Smithsonian Center for Astrophysics. The Department of Astronomy, under a Chair, continues as an autonomous unit under the direction of the Harvard University Faculty of Arts of Sciences but is housed at the CfA.

    The complement of approximately 60 PhD students, 25 undergraduate students and over 100 post-doctoral researchers enjoy access to the remarkable resources provided by both Harvard and Smithsonian faculties and facilities.

    Harvard is the oldest institution of higher education in the United States, established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. It was named after the College’s first benefactor, the young minister John Harvard of Charlestown, who upon his death in 1638 left his library and half his estate to the institution. A statue of John Harvard stands today in front of University Hall in Harvard Yard, and is perhaps the University’s best known landmark.

    Harvard University has 12 degree-granting Schools in addition to the Radcliffe Institute for Advanced Study. The University has grown from nine students with a single master to an enrollment of more than 20,000 degree candidates including undergraduate, graduate, and professional students. There are more than 360,000 living alumni in the U.S. and over 190 other countries.

     
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