Tagged: NASA ESA Hubble Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 11:18 am on January 29, 2020 Permalink | Reply
    Tags: , , Awesome facts about the Hubble Deep Field in images"., , , NASA ESA Hubble,   

    From Perimeter Institute: “14 mind-bogglingly awesome facts about the Hubble Deep Field images” 

    Perimeter Institute
    From Perimeter Institute

    Jan 28, 2020
    Perimeter Institute

    The landmark Deep Field image and its successors make the mind reel with their depictions of the universe’s unfathomable vastness.

    Hubble Ultra Deep Field NASA/ESA Hubble

    Perhaps the most incredible picture ever captured – aside from that picture you posted on Instagram of your cat wearing sunglasses, of course – is the Hubble Deep Field image.

    Released 24 years ago this month, the original Hubble Deep Field image conveys the staggering, incomprehensible quantity of stars and galaxies out there in the universe.

    Perhaps most incredibly, the Hubble Telescope captured the image by focusing on a tiny and seemingly “empty” patch of space with a very long exposure. This yielded an image containing thousands of galaxies and trillions – trillions! – of stars.

    Over the decades since the release of the first Deep Field image, follow-up observations and experiments (like the Hubble Ultra-Deep Field and the Hubble eXtreme Deep Field) have unveiled exquisitely detailed images of our early universe.

    Just last year, the ABYSS Hubble Ultra-Deep Field reprocessed the Ultra-Deep Field images to provide humanity with the deepest look into the cosmos yet.

    Feast your eyes and your mind on these Deep Field facts.

    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15

    Fascinating videos about the Hubble Deep Field

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Perimeter Institute is a leading centre for scientific research, training and educational outreach in foundational theoretical physics. Founded in 1999 in Waterloo, Ontario, Canada, its mission is to advance our understanding of the universe at the most fundamental level, stimulating the breakthroughs that could transform our future. Perimeter also trains the next generation of physicists through innovative programs, and shares the excitement and wonder of science with students, teachers and the general public.

     
  • richardmitnick 12:20 pm on January 24, 2020 Permalink | Reply
    Tags: "NASA's Kepler Witnesses Vampire Star System Undergoing Super-Outburst", , , , , NASA ESA Hubble,   

    From NASA/ESA Hubble Telescope and NASA/Kepler: “NASA’s Kepler Witnesses Vampire Star System Undergoing Super-Outburst” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope


    From NASA/ESA Hubble Telescope

    and

    NASA Kepler Logo

    NASA Kepler Telescope
    From NASA/Kepler

    January 24, 2020

    Christine Pulliam
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4366
    cpulliam@stsci.edu

    Ryan Ridden-Harper
    Space Telescope Science Institute, Baltimore, Maryland, and
    Australian National University, Canberra, Australia
    rridden@stsci.edu

    1
    NASA and L. Hustak

    This illustration shows a newly discovered dwarf nova system, in which a white dwarf star is pulling material off a brown dwarf companion. The material collects into an accretion disk until reaching a tipping point, causing it to suddenly increase in brightness. Using archival Kepler data, a team observed a previously unseen, and unexplained, gradual intensification followed by a super-outburst in which the system brightened by a factor of 1,600 over less than a day.

    Archival data reveals earliest stages of a dramatic event

    Astronomers searching archival data from NASA’s Kepler exoplanet hunting mission identified a previously unknown dwarf nova that underwent a super-outburst, brightening by a factor of 1,600 times in less than a day. While the outburst itself has a theoretical explanation, the slow rise in brightness that preceded it remains a mystery. Kepler’s rapid cadence of observations were crucial for recording the entire event in detail.

    The dwarf nova system consists of a white dwarf star with a brown dwarf companion. The white dwarf is stripping material from the brown dwarf, sucking its essence away like a vampire. The stripped material forms an accretion disk around the white dwarf, which is the source of the super-outburst. Such systems are rare and may go for years or decades between outbursts, making it a challenge to catch one in the act.

    NASA’s Kepler spacecraft was designed to find exoplanets by looking for stars that dim as a planet crosses the star’s face. Fortuitously, the same design makes it ideal for spotting other astronomical transients – objects that brighten or dim over time. A new search of Kepler archival data has uncovered an unusual super-outburst from a previously unknown dwarf nova. The system brightened by a factor of 1,600 over less than a day before slowly fading away.

    The star system in question consists of a white dwarf star with a brown dwarf companion about one-tenth as massive as the white dwarf. A white dwarf is the leftover core of an aging Sun-like star and contains about a Sun’s worth of material in a globe the size of Earth. A brown dwarf is an object with a mass between 10 and 80 Jupiters that is too small to undergo nuclear fusion.

    The brown dwarf circles the white dwarf star every 83 minutes at a distance of only 250,000 miles (400,000 km) – about the distance from Earth to the Moon. They are so close that the white dwarf’s strong gravity strips material from the brown dwarf, sucking its essence away like a vampire. The stripped material forms a disk as it spirals toward the white dwarf (known as an accretion disk).

    It was sheer chance that Kepler was looking in the right direction when this system underwent a super-outburst, brightening by more than 1,000 times. In fact, Kepler was the only instrument that could have witnessed it, since the system was too close to the Sun from Earth’s point of view at the time. Kepler’s rapid cadence of observations, taking data every 30 minutes, was crucial for catching every detail of the outburst.

    The event remained hidden in Kepler’s archive until identified by a team led by Ryan Ridden-Harper of the Space Telescope Science Institute (STScI), Baltimore, Maryland, and the Australian National University, Canberra, Australia. “In a sense, we discovered this system accidentally. We weren’t specifically looking for a super-outburst. We were looking for any sort of transient,” said Ridden-Harper.

    Kepler captured the entire event, observing a slow rise in brightness followed by a rapid intensification. While the sudden brightening is predicted by theories, the cause of the slow start remains a mystery. Standard theories of accretion disk physics don’t predict this phenomenon, which has subsequently been observed in two other dwarf nova super-outbursts.

    “These dwarf nova systems have been studied for decades, so spotting something new is pretty tricky,” said Ridden-Harper. “We see accretion disks all over – from newly forming stars to supermassive black holes – so it’s important to understand them.”

    Theories suggest that a super-outburst is triggered when the accretion disk reaches a tipping point. As it accumulates material, it grows in size until the outer edge experiences gravitational resonance with the orbiting brown dwarf. This might trigger a thermal instability, causing the disk to get superheated. Indeed, observations show that the disk’s temperature rises from about 5,000–10,000° F (2,700–5,300° C) in its normal state to a high of 17,000–21,000° F (9,700–11,700° C) at the peak of the super-outburst.

    This type of dwarf nova system is relatively rare, with only about 100 known. An individual system may go for years or decades between outbursts, making it a challenge to catch one in the act.

    “The detection of this object raises hopes for detecting even more rare events hidden in Kepler data,” said co-author Armin Rest of STScI.

    The team plans to continue mining Kepler data, as well as data from another exoplanet hunter, the Transiting Exoplanet Survey Satellite (TESS) mission, in search of other transients.

    NASA/MIT TESS replaced Kepler in search for exoplanets

    “The continuous observations by Kepler/K2, and now TESS, of these dynamic stellar systems allows us to study the earliest hours of the outburst, a time domain that is nearly impossible to reach from ground-based observatories,” said Peter Garnavich of the University of Notre Dame in Indiana.

    This work was published in the Oct. 21, 2019 issue of the Monthly Notices of the Royal Astronomical Society.

    The Space Telescope Science Institute is expanding the frontiers of space astronomy by hosting the science operations center of the Hubble Space Telescope, the science and operations center for the James Webb Space Telescope, and the science operations center for the future Wide Field Infrared Survey Telescope (WFIRST). STScI also houses the Mikulski Archive for Space Telescopes (MAST) which is a NASA-funded project to support and provide to the astronomical community a variety of astronomical data archives, and is the data repository for the Hubble, Webb, Kepler, K2, TESS missions and more.

    NASA/ESA/CSA Webb Telescope annotated

    NASA/WFIRST

    STScI also houses the Mikulski Archive for Space Telescopes (MAST) which is a NASA-funded project to support and provide to the astronomical community a variety of astronomical data archives, and is the data repository for the Hubble, Webb, Kepler, K2, TESS missions and more.

    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 Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

    ESA50 Logo large

     
  • richardmitnick 6:11 pm on January 8, 2020 Permalink | Reply
    Tags: "Cosmic Magnifying Glasses Yield Independent Measure of Universe's Expansion", , , , , NASA ESA Hubble   

    From NASA/ESA Hubble Telescope: “Cosmic Magnifying Glasses Yield Independent Measure of Universe’s Expansion” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope


    From NASA/ESA Hubble Telescope

    January 08, 2020

    Donna Weaver
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4493
    dweaver@stsci.edu

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    Sherry Suyu
    Max Planck Institute for Astrophysics, Garching, Germany
    suyu@mpa-garching.mpg.de

    Kenneth Wong
    University of Tokyo’s Kavli Institute for the Physics and Mathematics of the Universe, Chiba, Japan
    ken.wong@ipmu.jp

    Geoff Chih-Fan Chen
    University of California, Davis, California
    chfchen@ucdavis.edu

    1
    Mosaic of Gravitationally Lensed Quasars

    2
    Compass Image of Gravitationally Lensed Quasars

    New Hubble Measurement Strengthens Discrepancy in Universe’s Expansion Rate

    People use the phrase “Holy Cow” to express excitement. Playing with that phrase, researchers from an international collaboration developed an acronym—H0LiCOW—for their project’s name that expresses the excitement over their Hubble Space Telescope measurements of the universe’s expansion rate.

    Knowing the precise value for how fast the universe expands is important for determining the age, size, and fate of the cosmos. Unraveling this mystery has been one of the greatest challenges in astrophysics in recent years.

    Members of the H0LiCOW (H0 Lenses in COSMOGRAIL’s Wellspring) team used Hubble and a technique that is completely independent of any previous method to measure the universe’s expansion, a value called the Hubble constant.

    This latest value represents the most precise measurement yet using the gravitational lensing method, where the gravity of a foreground galaxy acts like a giant magnifying lens, amplifying and distorting light from background objects.

    Gravitational Lensing NASA/ESA

    This latest study did not rely on the traditional “cosmic distance ladder” technique to measure accurate distances to galaxies by using various types of stars as “milepost markers.” Instead, the researchers employed the exotic physics of gravitational lensing to calculate the universe’s expansion rate.

    The researchers’ result further strengthens a troubling discrepancy between the expansion rate calculated from measurements of the local universe and the rate as predicted from background radiation in the early universe, a time before galaxies and stars even existed. The new study adds evidence to the idea that new theories may be needed to explain what scientists are finding.

    A team of astronomers using NASA’s Hubble Space Telescope has measured the universe’s expansion rate using a technique that is completely independent of any previous method.

    Knowing the precise value for how fast the universe expands is important for determining the age, size, and fate of the cosmos. Unraveling this mystery has been one of the greatest challenges in astrophysics in recent years. The new study adds evidence to the idea that new theories may be needed to explain what scientists are finding.

    The researchers’ result further strengthens a troubling discrepancy between the expansion rate, called the Hubble constant, calculated from measurements of the local universe and the rate as predicted from background radiation in the early universe, a time before galaxies and stars even existed.

    This latest value represents the most precise measurement yet using the gravitational lensing method, where the gravity of a foreground galaxy acts like a giant magnifying lens, amplifying and distorting light from background objects. This latest study did not rely on the traditional “cosmic distance ladder” technique to measure accurate distances to galaxies by using various types of stars as “milepost markers.” Instead, the researchers employed the exotic physics of gravitational lensing to calculate the universe’s expansion rate.

    The astronomy team that made the new Hubble constant measurements is dubbed H0LiCOW (H0 Lenses in COSMOGRAIL’s Wellspring). COSMOGRAIL is the acronym for Cosmological Monitoring of Gravitational Lenses, a large international project whose goal is monitoring gravitational lenses. “Wellspring” refers to the abundant supply of quasar lensing systems.

    The research team derived the H0LiCOW value for the Hubble constant through observing and analysis techniques that have been greatly refined over the past two decades.

    H0LiCOW and other recent measurements suggest a faster expansion rate in the local universe than was expected based on observations by the European Space Agency’s Planck satellite of how the cosmos behaved more than 13 billion years ago.

    ESA/Planck 2009 to 2013

    The gulf between the two values has important implications for understanding the universe’s underlying physical parameters and may require new physics to account for the mismatch.

    “If these results do not agree, it may be a hint that we do not yet fully understand how matter and energy evolved over time, particularly at early times,” said H0LiCOW team leader Sherry Suyu of the Max Planck Institute for Astrophysics in Germany, the Technical University of Munich, and the Academia Sinica Institute of Astronomy and Astrophysics in Taipei, Taiwan.

    How they did it

    The H0LiCOW team used Hubble to observe the light from six faraway quasars, the brilliant searchlights from gas orbiting supermassive black holes at the centers of galaxies. Quasars are ideal background objects for many reasons; for example, they are bright, extremely distant, and scattered all over the sky. The telescope observed how the light from each quasar was multiplied into four images by the gravity of a massive foreground galaxy. The galaxies studied are 3 billion to 6.5 billion light-years away. The quasars’ average distance is 5.5 billion light-years from Earth.

    The light rays from each lensed quasar image take a slightly different path through space to reach Earth. The pathway’s length depends on the amount of matter that is distorting space along the line of sight to the quasar. To trace each pathway, the astronomers monitor the flickering of the quasar’s light as its black hole gobbles up material. When the light flickers, each lensed image brightens at a different time.

    This flickering sequence allows researchers to measure the time delays between each image as the lensed light travels along its path to Earth. To fully understand these delays, the team first used Hubble to make accurate maps of the distribution of matter in each lensing galaxy. Astronomers could then reliably deduce the distances from the galaxy to the quasar, and from Earth to the galaxy and to the background quasar. By comparing these distance values, the researchers measured the universe’s expansion rate.

    “The length of each time delay indicates how fast the universe is expanding,” said team member Kenneth Wong of the University of Tokyo’s Kavli Institute for the Physics and Mathematics of the Universe, lead author of the H0LiCOW collaboration’s most recent paper. “If the time delays are shorter, then the universe is expanding at a faster rate. If they are longer, then the expansion rate is slower.”

    The time-delay process is analogous to four trains leaving the same station at exactly the same time and traveling at the same speed to reach the same destination. However, each of the trains arrives at the destination at a different time. That’s because each train takes a different route, and the distance for each route is not the same. Some trains travel over hills. Others go through valleys, and still others chug around mountains. From the varied arrival times, one can infer that each train traveled a different distance to reach the same stop. Similarly, the quasar flickering pattern does not appear at the same time because some of the light is delayed by traveling around bends created by the gravity of dense matter in the intervening galaxy.

    How it compares

    The researchers calculated a Hubble constant value of 73 kilometers per second per megaparsec (with 2.4% uncertainty). This means that for every additional 3.3 million light-years away a galaxy is from Earth, it appears to be moving 73 kilometers per second faster, because of the universe’s expansion.

    The team’s measurement also is close to the Hubble constant value of 74 calculated by the Supernova H0 for the Equation of State (SH0ES) team, which used the cosmic distance ladder technique. The SH0ES measurement is based on gauging the distances to galaxies near and far from Earth by using Cepheid variable stars and supernovas as measuring sticks to the galaxies.

    The SH0ES and H0LiCOW values significantly differ from the Planck number of 67, strengthening the tension between Hubble constant measurements of the modern universe and the predicted value based on observations of the early universe.

    “One of the challenges we overcame was having dedicated monitoring programs through COSMOGRAIL to get the time delays for several of these quasar lensing systems,” said Frédéric Courbin of the Ecole Polytechnique Fédérale de Lausanne, leader of the COSMOGRAIL project.

    Suyu added: “At the same time, new mass modeling techniques were developed to measure a galaxy’s matter distribution, including models we designed to make use of the high-resolution Hubble imaging. The images enabled us to reconstruct, for example, the quasars’ host galaxies. These images, along with additional wider-field images taken from ground-based telescopes, also allow us to characterize the environment of the lens system, which affects the bending of light rays. The new mass modeling techniques, in combination with the time delays, help us to measure precise distances to the galaxies.”

    Begun in 2012, the H0LiCOW team now has Hubble images and time-delay information for 10 lensed quasars and intervening lensing galaxies. The team will continue to search for and follow up on new lensed quasars in collaboration with researchers from two new programs. One program, called STRIDES (STRong-lensing Insights into Dark Energy Survey), is searching for new lensed quasar systems. The second, called SHARP (Strong-lensing at High Angular Resolution Program), uses adaptive optics with the W.M. Keck telescopes to image the lensed systems.

    UCO Keck Laser Guide Star Adaptive Optics,Keck Observatory, operated by Caltech and the University of California, Maunakea Hawaii USA, 4,207 m (13,802 ft)

    The team’s goal is to observe 30 more lensed quasar systems to reduce their 2.4% percent uncertainty to 1%.

    NASA’s upcoming James Webb Space Telescope, expected to launch in 2021, may help them achieve their goal of 1% uncertainty much faster through Webb’s ability to map the velocities of stars in a lensing galaxy, which will allow astronomers to develop more precise models of the galaxy’s distribution of dark matter.

    The H0LiCOW team’s work also paves the way for studying hundreds of lensed quasars that astronomers are discovering through surveys such as the Dark Energy Survey and PanSTARRS (Panoramic Survey Telescope and Rapid Response System), and the upcoming National Science Foundation’s Large Synoptic Survey Telescope, which is expected to uncover thousands of additional sources.

    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

    Timeline of the Inflationary Universe WMAP

    The Dark Energy Survey (DES) is an international, collaborative effort to map hundreds of millions of galaxies, detect thousands of supernovae, and find patterns of cosmic structure that will reveal the nature of the mysterious dark energy that is accelerating the expansion of our Universe. DES began searching the Southern skies on August 31, 2013.

    According to Einstein’s theory of General Relativity, gravity should lead to a slowing of the cosmic expansion. Yet, in 1998, two teams of astronomers studying distant supernovae made the remarkable discovery that the expansion of the universe is speeding up. To explain cosmic acceleration, cosmologists are faced with two possibilities: either 70% of the universe exists in an exotic form, now called dark energy, that exhibits a gravitational force opposite to the attractive gravity of ordinary matter, or General Relativity must be replaced by a new theory of gravity on cosmic scales.

    DES is designed to probe the origin of the accelerating universe and help uncover the nature of dark energy by measuring the 14-billion-year history of cosmic expansion with high precision. More than 400 scientists from over 25 institutions in the United States, Spain, the United Kingdom, Brazil, Germany, Switzerland, and Australia are working on the project. The collaboration built and is using an extremely sensitive 570-Megapixel digital camera, DECam, mounted on the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory, high in the Chilean Andes, to carry out the project.

    Over six years (2013-2019), the DES collaboration used 758 nights of observation to carry out a deep, wide-area survey to record information from 300 million galaxies that are billions of light-years from Earth. The survey imaged 5000 square degrees of the southern sky in five optical filters to obtain detailed information about each galaxy. A fraction of the survey time is used to observe smaller patches of sky roughly once a week to discover and study thousands of supernovae and other astrophysical transients.

    Pann-STARS 1 Telescope, U Hawaii, situated at Haleakala Observatories near the summit of Haleakala in Hawaii, USA, altitude 3,052 m (10,013 ft)

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

    In addition, NASA’s Wide Field Infrared Survey Telescope (WFIRST) will help astronomers address the disagreement in the Hubble constant value by tracing the expansion history of the universe.

    NASA/WFIRST

    The mission will also use multiple techniques, such as sampling thousands of supernovae and other objects at various distances, to help determine whether the discrepancy is a result of measurement errors, observational technique, or whether astronomers need to adjust the theory from which they derive their predictions.

    The team will present its results at the 235th meeting of the American Astronomical Society in Honolulu, Hawaii.
    .

    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 Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

    ESA50 Logo large

    AURA Icon

     
  • richardmitnick 4:16 pm on January 8, 2020 Permalink | Reply
    Tags: "Goldilocks Stars Are Best Places to Look for Life", , , , , NASA ESA Hubble   

    From NASA/ESA Hubble Telescope: “Goldilocks Stars Are Best Places to Look for Life” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope


    From NASA/ESA Hubble Telescope

    January 08, 2020

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    Edward Guinan
    Villanova University, Villanova, Pennsylvania
    edward.guinan@villanova.edu

    1
    About This Image

    This infographic compares the characteristics of three classes of stars in our galaxy: Sunlike stars are classified as G stars; stars less massive and cooler than our Sun are K dwarfs; and even fainter and cooler stars are the reddish M dwarfs. The graphic compares the stars in terms of several important variables. The habitable zones, potentially capable of hosting life-bearing planets, are wider for hotter stars. The longevity for red dwarf M stars can exceed 100 billion years. K dwarf ages can range from 15 to 45 billion years. And, our Sun only lasts for 10 billion years. The relative amount of harmful radiation (to life as we know it) that stars emit can be 80 to 500 times more intense for M dwarfs relative to our Sun, but only 5 to 25 times more intense for the orange K dwarfs. Red dwarfs make up the bulk of the Milky Way’s population, about 73%. Sunlike stars are merely 6% of the population, and K dwarfs are at 13%. When these four variables are balanced, the most suitable stars for potentially hosting advanced life forms are K dwarfs.

    Summary

    Orange Dwarf Stars Most Likely to Host Planets

    To date astronomers have discovered over 4,000 planets orbiting other stars. Statistically, there should be over 100 billion planets in our Milky Way galaxy. They come in a wide range of sizes and characteristics, largely unimagined before exoplanets were first discovered in the mid-1990s. The biggest motivation for perusing these worlds is to find “Genesis II,” a planet where life has arisen and evolved beyond microbes. The ultimate payoff would be finding intelligent life off the Earth.

    A major step in searching for habitable planets is finding suitable stars that could foster the emergence of complex organisms. Because our Sun has nurtured life on Earth for nearly 4 billion years, conventional wisdom would suggest that stars like it would be prime candidates. But stars like our Sun represent only about 10% of the Milky Way population. What’s more, they are comparatively short-lived. Our Sun is halfway through its estimated 10 billion-year lifetime.

    Complex organisms arose on Earth only 500 million years ago. And, the modern form of humans has been here only for the blink of an eye on cosmological timescales: 200,000 years. The future of humanity is unknown. But what is for certain is that Earth will become uninhabitable for higher forms of life in a little over 1 billion years, as the Sun grows warmer and desiccates our planet.

    Therefore, stars slightly cooler than our Sun — called orange dwarfs — are considered better hang-outs for advanced life. They can burn steadily for tens of billions of years. This opens up a vast timescape for biological evolution to pursue an infinity of experiments for yielding robust life forms. And, for every star like our Sun there are three times as many orange dwarfs in the Milky Way.

    The only type of star that is more abundant are red dwarfs. But these are feisty little stars. They are so magnetically active they pump out 500 times as much radiation in the form of X-rays and ultraviolet light as our Sun does. Planets around these stars take a beating. They would be no place to call home for organisms like us.

    An emerging idea, bolstered by stellar surveys performed by Hubble and other telescopes, is that the orange dwarfs are “Goldilocks stars” — not too hot, not too cool, and above all, not too violent to host life-friendly planets over a vast horizon of cosmic time.

    In the search for life beyond Earth, astronomers look for planets in a star’s “habitable zone” — sometimes nicknamed the “Goldilocks zone” — where temperatures are just right for liquid water to exist on a planet’s surface to nurture life as we know it.

    An emerging idea, bolstered by a three-decade-long set of stellar surveys, is that there are “Goldilocks stars” — not too hot, not too cool, and above all, not too violent to host life-friendly planets.

    Because our Sun has nurtured life on Earth for nearly 4 billion years, conventional wisdom would suggest that stars like it would be prime candidates in the search for other potentially habitable worlds. In reality, stars slightly cooler and less luminous than our Sun, classified as K dwarfs, are the true “Goldilocks stars,” said Edward Guinan of Villanova University, Villanova, Pennsylvania. “K-dwarf stars are in the ‘sweet spot,’ with properties intermediate between the rarer, more luminous, but shorter-lived solar-type stars (G stars) and the more numerous red dwarf stars (M stars). The K stars, especially the warmer ones, have the best of all worlds. If you are looking for planets with habitability, the abundance of K stars pump up your chances of finding life.”

    For starters, there are three times as many K dwarfs in our galaxy as stars like our Sun. Roughly 1,000 K stars lie within 100 light-years of our Sun as prime candidates for exploration. These so-called orange dwarfs live from 15 billion to 45 billion years. By contrast, our Sun, now already halfway through its lifetime, lasts for only 10 billion years. Its comparatively rapid rate of stellar evolution will leave the Earth largely uninhabitable in just another 1 or 2 billion years. “Solar-type stars limit how long a planet’s atmosphere can remain stable,” Guinan said. That’s because a billion or so years from now, Earth will orbit inside the hotter (inner) edge of the Sun’s habitable zone, which moves outward as the Sun grows warmer and brighter. As a result, the Earth will be desiccated as it loses its present atmosphere and oceans. By an age of 9 billion years the Sun will have swelled up to become a red giant that could engulf the Earth.

    Despite their small size, the even more abundant red dwarf stars, also known as M dwarf stars, have even longer lifetimes and appear to be hostile to life as we know it. Planets that are located in a red dwarf’s comparatively narrow habitable zone, which is very close to the star, are exposed to extreme levels of X-ray and ultraviolet (UV) radiation, which can be up to hundreds of thousands of times more intense than what Earth receives from the Sun. A relentless fireworks show of flares and coronal mass ejections bombard planets with a dragon’s breath of seething plasma and showers of penetrating high-energy particles. Red dwarf habitable-zone planets can be baked bone dry and have their atmospheres stripped away very early in their lives. This could likely prohibit the planets from evolving to be more hospitable a few billion years after red dwarf outbursts have subsided. “We’re not so optimistic anymore about the chances of finding advanced life around many M stars,” Guinan said.

    The K dwarfs do not have intensely active magnetic fields that power strong X-ray and UV emissions and energetic outbursts, and therefore they shoot off flares much less frequently, based on Guinan’s research. Accompanying planets would get about 1/100th as much deadly X-ray radiation as those orbiting the close-in habitable zones of magnetically-active M stars.

    In a program called the “GoldiloKs” Project, Guinan and his Villanova colleague Scott Engle, are working with undergraduate students to measure the age, rotation rate, and X-ray and far-ultraviolet radiation in a sampling of mostly cool G and K stars.They are using NASA’s Hubble Space Telescope, Chandra X-ray Observatory, and the European Space Agency’s XMM-Newton satellite for their observations.

    NASA/Chandra X-ray Telescope

    ESA/XMM Newton

    Hubble’s sensitive ultraviolet-light observations of radiation from hydrogen were used to assess the radiation from a sample of about 20 orange dwarfs. “Hubble is the only telescope that can do this kind of observation,” Guinan said.

    Guinan and Engle found that the levels of radiation were much more benign to any accompanying planets than those found around red dwarfs. K stars also have longer lifetimes and therefore slower migration of the habitable zone. Therefore, K dwarfs seem like the ideal place to go looking for life, and these stars would allow time for highly evolved life to develop on planets. Over the Sun’s entire lifetime — 10 billion years — K stars only increase their brightness by about 10-15%, giving biological evolution a much longer timespan to evolve advanced life forms than on Earth.

    Guinan and Engle looked at some of the more interesting K stars hosting planets, including Kepler-442, Tau Ceti, and Epsilon Eridani. (The latter two were early targets of the late 1950s Project Ozma — the first attempt to detect radio transmissions from extraterrestrial civilizations.)

    “Kepler-442 is noteworthy in that this star (spectral classification, K5) hosts what is considered one of the best Goldilocks planets, Kepler-442b, a rocky planet that is a little more than twice Earth’s mass. So the Kepler-442 system is a Goldilocks planet hosted by a Goldilocks star!” said Guinan.

    Over the last 30 years Guinan and Engle and their students have observed a variety of stellar types. Based on their studies, the researchers have determined relationships among stellar age, rotation rate, X-ray-UV emissions and flare activity. These data have been utilized to investigate the effects of high-energy radiation on planet atmospheres and possible life.

    The results are being presented at the 235th meeting of the American Astronomical Society
    in Honolulu, Hawaii.

    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 Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

    ESA50 Logo large

    AURA Icon

     
  • richardmitnick 3:34 pm on January 8, 2020 Permalink | Reply
    Tags: "Hubble Detects Smallest Known Dark Matter Clumps", , , , , NASA ESA Hubble   

    From NASA/ESA Hubble Telescope: “Hubble Detects Smallest Known Dark Matter Clumps” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope


    From NASA/ESA Hubble Telescope

    January 08, 2020
    Donna Weaver
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4493
    dweaver@stsci.edu

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    Anna Nierenberg
    Jet Propulsion Laboratory, Pasadena, California
    818-393-5095
    anna.m.nierenberg@jpl.nasa.gov

    Tommaso Treu
    University of California, Los Angeles, California
    310-206-5617 (office) / 757-814-5869 (cell)
    tt@astro.ucla.edu

    Daniel Gilman
    University of California, Los Angeles, California
    310-206-5617 (office) / 757-814-5869 (cell)
    gilmana@ucla.edu

    1
    Release images

    2
    Gravitationally Lensed Quasars

    3
    Illustration of Strong Gravitational Lensing

    4
    Compass Image of Gravitationally Lensed Quasars

    Using NASA’s Hubble Space Telescope and a new observing technique, astronomers have found that dark matter forms much smaller clumps than previously known. This result confirms one of the fundamental predictions of the widely accepted “cold dark matter” theory.

    Lambda-Cold Dark Matter, Accelerated Expansion of the Universe, Big Bang-Inflation (timeline of the universe) Date 2010 Credit: Alex Mittelmann Cold creation

    Fritz Zwicky discovered Dark Matter when observing the movement of the Coma Cluster., Vera Rubin a Woman in STEM denied the Nobel, did most of the work on Dark Matter.

    Fritz Zwicky from http:// palomarskies.blogspot.com

    Coma cluster via NASA/ESA Hubble

    Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science)


    Vera Rubin measuring spectra, worked on Dark Matter (Emilio Segre Visual Archives AIP SPL)


    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970. https://home.dtm.ciw.edu

    The LSST, or Large Synoptic Survey Telescope is to be named the Vera C. Rubin Observatory by an act of the U.S. Congress.

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

    LSST Data Journey, Illustration by Sandbox Studio, Chicago with Ana Kova

    Dark Matter Research

    Universe map Sloan Digital Sky Survey (SDSS) 2dF Galaxy Redshift Survey

    Scientists studying the cosmic microwave background hope to learn about more than just how the universe grew—it could also offer insight into dark matter, dark energy and the mass of the neutrino.

    Dark matter cosmic web and the large-scale structure it forms The Millenium Simulation, V. Springel et al

    Dark Matter Particle Explorer China

    DEAP Dark Matter detector, The DEAP-3600, suspended in the SNOLAB deep in Sudbury’s Creighton Mine

    LBNL LZ Dark Matter project at SURF, Lead, SD, USA


    Inside the ADMX experiment hall at the University of Washington Credit Mark Stone U. of Washington. Axion Dark Matter Experiment

    All galaxies, according to this theory, form and are embedded within clouds of dark matter. Dark matter itself consists of slow-moving, or “cold,” particles that come together to form structures ranging from hundreds of thousands of times the mass of the Milky Way galaxy to clumps no more massive than the heft of a commercial airplane. (In this context, “cold” refers to the particles’ speed.)

    The Hubble observation yields new insights into the nature of dark matter and how it behaves. “We made a very compelling observational test for the cold dark matter model and it passes with flying colors,” said Tommaso Treu of the University of California, Los Angeles (UCLA), a member of the observing team.

    Dark matter is an invisible form of matter that makes up the bulk of the universe’s mass and creates the scaffolding upon which galaxies are built. Although astronomers cannot see dark matter, they can detect its presence indirectly by measuring how its gravity affects stars and galaxies. Detecting the smallest dark matter formations by looking for embedded stars can be difficult or impossible, because they contain very few stars.

    While dark matter concentrations have been detected around large- and medium-sized galaxies, much smaller clumps of dark matter have not been found until now. In the absence of observational evidence for such small-scale clumps, some researchers have developed alternative theories, including “warm dark matter.” This idea suggests that dark matter particles are fast moving, zipping along too quickly to merge and form smaller concentrations. The new observations do not support this scenario, finding that dark matter is “colder” than it would have to be in the warm dark matter alternative theory.

    “Dark matter is colder than we knew at smaller scales,” said Anna Nierenberg of NASA’s Jet Propulsion Laboratory in Pasadena, California, leader of the Hubble survey. “Astronomers have carried out other observational tests of dark matter theories before, but ours provides the strongest evidence yet for the presence of small clumps of cold dark matter. By combining the latest theoretical predictions, statistical tools, and new Hubble observations, we now have a much more robust result than was previously possible.”

    Hunting for dark matter concentrations devoid of stars has proved challenging. The Hubble research team, however, used a technique in which they did not need to look for the gravitational influence of stars as tracers of dark matter. The team targeted eight powerful and distant cosmic “streetlights,” called quasars (regions around active black holes that emit enormous amounts of light). The astronomers measured how the light emitted by oxygen and neon gas orbiting each of the quasars’ black holes is warped by the gravity of a massive foreground galaxy, which is acting as a magnifying lens.

    Using this method, the team uncovered dark matter clumps along the telescope’s line of sight to the quasars, as well as in and around the intervening lensing galaxies. The dark matter concentrations detected by Hubble are 1/10,000th to 1/100,000th times the mass of the Milky Way’s dark matter halo. Many of these tiny groupings most likely do not contain even small galaxies, and therefore would have been impossible to detect by the traditional method of looking for embedded stars.

    The eight quasars and galaxies were aligned so precisely that the warping effect, called gravitational lensing, produced four distorted images of each quasar.

    Gravitational Lensing NASA/ESA

    The effect is like looking at a funhouse mirror. Such quadruple images of quasars are rare because of the nearly exact alignment needed between the foreground galaxy and background quasar. However, the researchers needed the multiple images to conduct a more detailed analysis.

    The presence of the dark matter clumps alters the apparent brightness and position of each distorted quasar image. Astronomers compared these measurements with predictions of how the quasar images would look without the influence of the dark matter. The researchers used the measurements to calculate the masses of the tiny dark matter concentrations. To analyze the data, the researchers also developed elaborate computing programs and intensive reconstruction techniques.

    “Imagine that each one of these eight galaxies is a giant magnifying glass,” explained team member Daniel Gilman of UCLA. “Small dark matter clumps act as small cracks on the magnifying glass, altering the brightness and position of the four quasar images compared to what you would expect to see if the glass were smooth.”

    The researchers used Hubble’s Wide Field Camera 3 to capture the near-infrared light from each quasar and disperse it into its component colors for study with spectroscopy.

    NASA/ESA Hubble WFC3

    Unique emissions from the background quasars are best seen in infrared light. “Hubble’s observations from space allow us to make these measurements in galaxy systems that would not be accessible with the lower resolution of ground-based telescopes—and Earth’s atmosphere is opaque to the infrared light we needed to observe,” explained team member Simon Birrer of UCLA.

    Treu added: “It’s incredible that after nearly 30 years of operation, Hubble is enabling cutting-edge views into fundamental physics and the nature of the universe that we didn’t even dream of when the telescope was launched.”

    The gravitational lenses were discovered by sifting through ground-based surveys such as the Sloan Digital Sky Survey and Dark Energy Survey, which provide the most detailed three-dimensional maps of the universe ever made. The quasars are located roughly 10 billion light-years from Earth; the foreground galaxies, about 2 billion light-years.

    SDSS Telescope at Apache Point Observatory, near Sunspot NM, USA, Altitude2,788 meters (9,147 ft)

    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

    Timeline of the Inflationary Universe WMAP

    The Dark Energy Survey (DES) is an international, collaborative effort to map hundreds of millions of galaxies, detect thousands of supernovae, and find patterns of cosmic structure that will reveal the nature of the mysterious dark energy that is accelerating the expansion of our Universe. DES began searching the Southern skies on August 31, 2013.

    According to Einstein’s theory of General Relativity, gravity should lead to a slowing of the cosmic expansion. Yet, in 1998, two teams of astronomers studying distant supernovae made the remarkable discovery that the expansion of the universe is speeding up. To explain cosmic acceleration, cosmologists are faced with two possibilities: either 70% of the universe exists in an exotic form, now called dark energy, that exhibits a gravitational force opposite to the attractive gravity of ordinary matter, or General Relativity must be replaced by a new theory of gravity on cosmic scales.

    DES is designed to probe the origin of the accelerating universe and help uncover the nature of dark energy by measuring the 14-billion-year history of cosmic expansion with high precision. More than 400 scientists from over 25 institutions in the United States, Spain, the United Kingdom, Brazil, Germany, Switzerland, and Australia are working on the project. The collaboration built and is using an extremely sensitive 570-Megapixel digital camera, DECam, mounted on the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory, high in the Chilean Andes, to carry out the project.

    Over six years (2013-2019), the DES collaboration used 758 nights of observation to carry out a deep, wide-area survey to record information from 300 million galaxies that are billions of light-years from Earth. The survey imaged 5000 square degrees of the southern sky in five optical filters to obtain detailed information about each galaxy. A fraction of the survey time is used to observe smaller patches of sky roughly once a week to discover and study thousands of supernovae and other astrophysical transients.

    The number of small structures detected in the study offers more clues about dark matter’s nature. “The particle properties of dark matter affect how many clumps form,” Nierenberg explained. “That means you can learn about the particle physics of dark matter by counting the number of small clumps.”

    However, the type of particle that makes up dark matter is still a mystery. “At present, there’s no direct evidence in the lab that dark matter particles exist,” Birrer said. “Particle physicists would not even talk about dark matter if the cosmologists didn’t say it’s there, based on observations of its effects. When we cosmologists talk about dark matter, we’re asking ‘how does it govern the appearance of the universe, and on what scales?'”

    Astronomers will be able to conduct follow-up studies of dark matter using future NASA space telescopes such as the James Webb Space Telescope and the Wide Field Infrared Survey Telescope (WFIRST), both infrared observatories.

    NASA/ESA/CSA Webb Telescope annotated

    NASA/WFIRST

    Webb will be capable of efficiently obtaining these measurements for all known quadruply lensed quasars. WFIRST’s sharpness and large field of view will help astronomers make observations of the entire region of space affected by the immense gravitational field of massive galaxies and galaxy clusters. This will help researchers uncover many more of these rare systems.

    The team will present its results at the 235th meeting of the American Astronomical Society
    in Honolulu, Hawaii.

    Science papers:
    The science paper by D. Gilman et al.
    MNRAS

    The science paper by A. Nierenberg et al.
    MNRAS

    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 Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

    ESA50 Logo large

    AURA Icon

     
  • richardmitnick 11:35 am on January 6, 2020 Permalink | Reply
    Tags: "Majestic Spiral Has Slowly Grown Over Billions of Years", , , , , NASA ESA Hubble, The galaxy UGC 2885   

    From NASA/ESA Hubble Telescope: “Majestic Spiral Has Slowly Grown Over Billions of Years” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope


    From NASA/ESA Hubble Telescope

    January 05, 2020

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    Benne Holwerda
    University of Louisville, Louisville, Kentucky
    502-852-0918
    bwholw01@louisville.edu

    1

    Summary
    Majestic Spiral Has Slowly Grown Over Billions of Years

    Galaxies are like snowflakes. Though the universe contains innumerable galaxies flung across time and space, no two ever look alike. One of the most photogenic is the huge spiral galaxy UGC 2885, located 232 million light-years away in the northern constellation, Perseus. It’s a whopper even by galactic standards. The galaxy is 2.5 times wider than our Milky Way and contains 10 times as many stars, about 1 trillion. This galaxy has lived a quiescent life by not colliding with other large galaxies. It has gradually bulked up on intergalactic hydrogen to make new stars at a slow and steady pace over many billions of years. The galaxy has been nicknamed “Rubin’s galaxy,” after astronomer Vera Rubin (1928 – 2016). Rubin used the galaxy to look for invisible dark matter. The galaxy is embedded inside a vast halo of dark matter. The amount of dark matter can be estimated by measuring its gravitational influence on the galaxy’s rotation rate.

    This majestic spiral galaxy might earn the nickname the “Godzilla Galaxy” because it may be the largest known in the local universe. The galaxy, UGC 2885, is 2.5 times wider than our Milky Way and contains 10 times as many stars.

    But it is a “gentle giant,” say researchers, because it looks like it has been sitting quietly over billions of years, possibly sipping hydrogen from the filamentary structure of intergalactic space. This fuels modest ongoing star birth at half the rate of our Milky Way. In fact, its supermassive central black hole is a sleeping giant, too; because the galaxy does not appear to be feeding on much smaller satellite galaxies, it is starved of infalling gas.

    The galaxy has been nicknamed “Rubin’s galaxy,” after astronomer Vera Rubin (1928 – 2016) by Benne Holwerda of the University of Louisville, Kentucky, who observed the galaxy with NASA’s Hubble Space Telescope.

    “My research was in a large part inspired by Vera Rubin’s work in 1980 on the size of this galaxy.” Rubin measured the galaxy’s rotation, which provides evidence for dark matter, which makes up most of the galaxy’s mass as measured by the rotation rate.

    Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science)

    Vera Rubin measuring spectra, worked on Dark Matter (Emilio Segre Visual Archives AIP SPL)

    “We consider this a commemorative image. This goal to cite Dr. Rubin in our observation was very much part of our original Hubble proposal.”

    In results being presented at the winter American Astronomical Society meeting in Honolulu, Hawaii
    , Holwerda is seeking to understand what led to the galaxy’s monstrous size. “How it got so big is something we don’t quite know yet,” said Holwerda. “It’s as big as you can make a disk galaxy without hitting anything else in space.”

    One clue is that the galaxy is fairly isolated in space and doesn’t have any nearby galaxies to crash into and disrupt the shape of its disk.

    Did the monster galaxy gobble up much smaller satellite galaxies over time? Or did it just slowly accrete gas for new stars? “It seems like it’s been puttering along, slowly growing,” Holwerda said. Using Hubble’s exceptional resolution, his team is counting the number of globular star clusters in the galaxy’s halo — a vast shell of faint stars surrounding the galaxy. An excess of clusters would yield evidence that they were captured from smaller infalling galaxies over many billions of years.

    NASA’s upcoming James Webb Space Telescope could be used to explore the center of this galaxy as well as the globular cluster population.

    NASA/ESA/CSA Webb Telescope annotated

    NASA’s planned Wide Field Infrared Survey Telescope (WFIRST) would give an even more complete census of this galaxy’s cluster population, especially that of the whole halo.

    NASA/WFIRST

    “The infrared capability of both space telescopes would give us a more unimpeded view of the underlying stellar populations,” said Holwerda. This complements Hubble’s visible-light ability to track wispy star formation throughout the galaxy.

    A number of foreground stars in our Milky Way can be seen in the image, identified by their diffraction spikes. The brightest appears to sit on top of the galaxy’s disk, though UGC 2885 is really 232 million light-years farther away. The giant galaxy is located in the northern constellation Perseus.

    The Space Telescope Science Institute is expanding the frontiers of space astronomy by hosting the science operations center of the Hubble Space Telescope, the science and operations center for the James Webb Space Telescope, and the science operations center for the future Wide Field Infrared Survey Telescope (WFIRST). STScI also houses the Mikulski Archive for Space Telescopes (MAST) which is a NASA-funded project to support and provide to the astronomical community a variety of astronomical data archives, and is the data repository for the Hubble, Webb, Kepler, K2, TESS missions and more.

    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 Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

    ESA50 Logo large

    AURA Icon

     
  • richardmitnick 12:07 am on January 6, 2020 Permalink | Reply
    Tags: "NASA's Great Observatories Help Astronomers Build a 3D Visualization of Exploded Star", , , , , , NASA ESA Hubble,   

    From NASA/ESA Hubble Telescope: “NASA’s Great Observatories Help Astronomers Build a 3D Visualization of Exploded Star” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope


    From NASA/ESA Hubble Telescope

    January 05, 2020

    Donna Weaver
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4493
    dweaver@stsci.edu

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    Frank Summers
    Space Telescope Science Institute, Baltimore, Maryland
    summers@stsci.edu

    1

    Summary
    Movie Dissects the Nebula’s Intricate Nested Structure

    In the year 1054 AD, Chinese sky watchers witnessed the sudden appearance of a “new star” in the heavens, which they recorded as six times brighter than Venus, making it the brightest observed stellar event in recorded history.

    2
    Crab Nebula

    This “guest star,” as they described it, was so bright that people saw it in the sky during the day for almost a month. Native Americans also recorded its mysterious appearance in petroglyphs.

    Observing the nebula with the largest telescope of the time, Lord Rosse in 1844 named the object the “Crab” because of its tentacle-like structure. But it wasn’t until the 1900s that astronomers realized the nebula was the surviving relic of the 1054 supernova, the explosion of a massive star.

    Now, astronomers and visualization specialists from the NASA’s Universe of Learning program have combined the visible, infrared, and X-ray vision of NASA’s Great Observatories to create a three-dimensional representation of the dynamic Crab Nebula.

    The multiwavelength computer graphics visualization is based on images from the Chandra X-ray Observatory and the Hubble and Spitzer space telescopes.

    NASA/Chandra X-ray Telescope

    NASA/Spitzer Infrared Telescope

    Astronomers and visualization specialists from the NASA’s Universe of Learning program
    have combined the visible, infrared, and X-ray vision of NASA’s Great Observatories to create a three-dimensional representation of the dynamic Crab Nebula, the tattered remains of an exploded star.

    The multiwavelength computer graphics visualization is based on images from the Chandra X-ray Observatory and the Hubble
    and Spitzer space telescopes.

    The approximately four-minute video dissects the intricate nested structure that makes up this stellar corpse, giving viewers a better understanding of the extreme and complex physical processes powering the nebula. The powerhouse “engine” energizing the entire system is a pulsar, a rapidly spinning neutron star, the super-dense crushed core of the exploded star. The tiny dynamo is blasting out blistering pulses of radiation 30 times a second with unbelievable clockwork precision.

    The visualization was produced by a team at the Space Telescope Science Institute (STScI) in Baltimore, Maryland; the Caltech/IPAC in Pasadena, California; and the Center for Astrophysics | Harvard & Smithsonian (CfA) in Cambridge, Massachusetts. It will debut at the American Astronomical Society meeting in Honolulu, Hawaii. The movie is available to planetariums and other centers of informal learning worldwide.

    “Seeing two-dimensional images of an object, especially of a complex structure like the Crab Nebula, doesn’t give you a good idea of its three-dimensional nature,” explained STScI’s visualization scientist Frank Summers, who led the team that developed the movie. “With this scientific interpretation, we want to help people understand the Crab Nebula’s nested and interconnected geometry. The interplay of the multiwavelength observations illuminate all of these structures. Without combining X-ray, infrared, and visible light, you don’t get the full picture.”

    Certain structures and processes, driven by the pulsar engine at the heart of the nebula, are best seen at particular wavelengths.

    The movie begins by showing the Crab Nebula in context, pinpointing its location in the constellation Taurus. This view zooms in to present the Hubble, Spitzer, and Chandra images of the Crab Nebula, each highlighting one of the nested structures in the system. The video then begins a slow buildup of the three-dimensional X-ray structure, showing the pulsar and a ringed disk of energized material, and adding jets of particles firing off from opposite sides of the energetic dynamo.

    Appearing next is a rotating infrared view of a cloud enveloping the pulsar system, and glowing from synchrotron radiation. This distinctive form of radiation occurs when streams of charged particles spiral around magnetic field lines. There is also infrared emission from dust and gas.

    The visible-light outer shell of the Crab Nebula appears next. Looking like a cage around the entire system, this shell of glowing gas consists of tentacle-shaped filaments of ionized oxygen (oxygen missing one or more electrons). The tsunami of particles unleashed by the pulsar is pushing on this expanding debris cloud like an animal rattling its cage.

    The X-ray, infrared, and visible-light models are combined at the end of the movie to reveal both a rotating three-dimensional multiwavelength view and the corresponding two-dimensional multiwavelength image of the Crab Nebula.

    The three-dimensional structures serve as scientifically informed approximations for imagining the nebula. “The three-dimensional views of each nested structure give you an idea of its true dimensions,” Summers said. “To enable viewers to develop a complete mental model, we wanted to show each structure separately, from the ringed disk and jets in stark relief, to the synchrotron radiation as a cloud around that, and then the visible light as a cage structure surrounding the entire system.”

    These nested structures are particular to the Crab Nebula. They reveal that the nebula is not a classic supernova remnant as once commonly thought. Instead, the system is better classified as a pulsar wind nebula. A traditional supernova remnant consists of a blast wave, and debris from the supernova that has been heated to millions of degrees. In a pulsar wind nebula, the system’s inner region consists of lower-temperature gas that is heated up to thousands of degrees by the high-energy synchrotron radiation.

    “It is truly via the multiwavelength structure that you can more cleanly comprehend that it’s a pulsar wind nebula,” Summers said. “This is an important learning objective. You can understand the energy from the pulsar at the core moving out to the synchrotron cloud, and then further out to the filaments of the cage.”

    Summers and the STScI visualization team worked with Robert Hurt, lead visualization scientist at IPAC, on the Spitzer images; and Nancy Wolk, imaging processing specialist at the Chandra X-ray Center at the CfA, on the Chandra images. Their initial step was reviewing past research on the Crab Nebula, an intensely studied object that formed from a supernova seen in 1054 by Chinese astronomers.

    Starting with the two-dimensional Hubble, Spitzer, and Chandra images, the team worked with experts to analyze the complex nested structures comprising the nebula and identify the best wavelength to represent each component. The three-dimensional interpretation is guided by scientific data, knowledge, and intuition, with artistic features filling out the structures.

    The visualization is one of a new generation of products and experiences being developed by the NASA’s Universe of Learning program. The effort combines a direct connection to the science and scientists of NASA’s Astrophysics missions with attention to audience needs to enable youth, families, and lifelong learners to explore fundamental questions in science, experience how science is done, and discover the universe for themselves.

    This video demonstrates the power of multiwavelength astronomy. It helps audiences understand how and why astronomers use multiple regions of the electromagnetic spectrum to explore and learn about our universe.

    NASA’s Universe of Learning materials are based upon work supported by NASA under cooperative agreement award number NNX16AC65A to the Space Telescope Science Institute, working in partnership with Caltech/IPAC, Jet Propulsion Laboratory, CfA, and Sonoma State 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

    The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

    ESA50 Logo large

    AURA Icon

     
  • richardmitnick 1:54 pm on December 30, 2019 Permalink | Reply
    Tags: "These Are The Most Distant Astronomical Objects In The Known Universe", , , , , , , , , , NASA ESA Hubble, , Our most distant “standard candle” for probing the Universe is SN UDS10Wil located 17 billion light-years (Gly), , , ,   

    From Ethan Siegel: “These Are The Most Distant Astronomical Objects In The Known Universe” 

    From Ethan Siegel
    Dec 30, 2019

    Astronomy’s enduring quest is to go farther, fainter, and more detailed than ever before. Here’s the edge of the cosmic frontier.

    1
    The distant galaxy MACS1149-JD1 is gravitationally lensed by a foreground cluster, allowing it to be imaged at high resolution and in multiple instruments, even without next-generation technology.

    Gravitational Lensing NASA/ESA

    This galaxy’s light comes to us from 530 million years after the Big Bang, but the stars within it are at least 280 million years old. It is the second-most distant galaxy with a spectroscopically confirmed distance, placing it 30.7 billion light-years away from us. (ALMA (ESO/NAOJ/NRAO), NASA/ESA HUBBLE SPACE TELESCOPE, W. ZHENG (JHU), M. POSTMAN (STSCI), THE CLASH TEAM, HASHIMOTO ET AL.)

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

    NASA/ESA Hubble Telescope

    Astronomers have always sought to push back the viewable distance frontiers.

    2
    Although there are magnified, ultra-distant, very red and even infrared galaxies in the eXtreme Deep Field, there are galaxies that are even more distant out there than what we’ve discovered in our deepest-to-date views. These galaxies will always remain visible to us, but we will never see them as they are today: 13.8 billion years after the Big Bang. (NASA, ESA, R. BOUWENS AND G. ILLINGWORTH (UC, SANTA CRUZ))

    More distant galaxies appear fainter, smaller, bluer, and less evolved overall.

    3
    Galaxies comparable to the present-day Milky Way are numerous, but younger galaxies that are Milky Way-like are inherently smaller, bluer, more chaotic, and richer in gas in general than the galaxies we see today. For the first galaxies of all, this ought to be taken to the extreme, and remains valid as far back as we’ve ever seen. The exceptions, when we encounter them, are both puzzling and rare. (NASA AND ESA)

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

    Laniakea supercluster. From Nature The Laniakea supercluster of galaxies R. Brent Tully, Hélène Courtois, Yehuda Hoffman & Daniel Pomarède at http://www.nature.com/nature/journal/v513/n7516/full/nature13674.html. Milky Way is the red dot.

    Individual planets and stars are only known relatively nearby, as our tools cannot take us farther.

    Local Group. Andrew Z. Colvin 3 March 2011

    4
    A massive cluster (left) magnified a distant star known as Icarus more than 2,000 times, making it visible from Earth (lower right) even though it is 9 billion light years away, far too distant to be seen individually with current telescopes. It was not visible in 2011 (upper right). The brightening leads us to believe that this was a blue supergiant star, formally named MACS J1149 Lensed Star 1. (NASA, ESA, AND P. KELLY (UNIVERSITY OF MINNESOTA))

    As the 2010s end, here are our presently known most distant astronomical objects.

    4
    The ultra-distant supernova SN UDS10Wil, shown here, is the farthest type Ia supernova ever discovered, whose light arrives today from a position 17 billion light-years away.

    A white dwarf fed by a normal star reaches the critical mass and explodes as a type Ia supernova. Credit: NASA/CXC/M Weiss

    Type Ia supernovae are used as distance indicators because of their standard intrinsic brightnesses, and are some of our strongest evidence for the accelerated expansion best explained by dark energy.

    Standard Candles to measure age and distance of the universe from supernovae NASA

    (NASA, ESA, A. RIESS (STSCI AND JHU), AND D. JONES AND S. RODNEY (JHU))

    The farthest type Ia supernova, our most distant “standard candle” for probing the Universe, is SN UDS10Wil, located 17 billion light-years (Gly) away.

    4
    This illustration of superluminous supernova SN 1000+0216, the most distant supernova ever observed at a redshift of z=3.90, from when the Universe was just 1.6 billion years old, is the current record-holder for individual supernovae. Unlike SN UDS10Wil, this supernova is a Type II (core collapse) supernova, and may have formed via the pair instability mechanism, which would explain its extraordinarily large intrinsic brightness. (ADRIAN MALEC AND MARIE MARTIG (SWINBURNE UNIVERSITY))

    The most distant supernova of all, 2012’s superluminous SN 1000+0216, occurred 23 Gly away.

    6
    The most distant X-ray jet in the Universe, from quasar GB 1428, sends us light from when the Universe was a mere 1.25 billion years old: less than 10% its current age. This jet comes from electrons heating CMB photons, and is over 230,000 light-years in extent: approximately double the size of the Milky Way. (X-RAY: NASA/CXC/NRC/C.CHEUNG ET AL; OPTICAL: NASA/STSCI; RADIO: NSF/NRAO/VLA)

    NASA/Chandra X-ray Telescope

    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)

    The most distant quasar jet, revealed by GB 1428+4217’s X-rays, is 25.4 Gly distant.

    7
    This image of ULAS J1120+0641, a very distant quasar powered by a black hole with a mass two billion times that of the Sun, was created from images taken from surveys made by both the Sloan Digital Sky Survey and the UKIRT Infrared Deep Sky Survey.

    SDSS Telescope at Apache Point Observatory, near Sunspot NM, USA, Altitude2,788 meters (9,147 ft)


    UKIRT, located on Mauna Kea, Hawai’i, USA as part of Mauna Kea Observatory,4,207 m (13,802 ft) above sea level

    The quasar appears as a faint red dot close to the centre. This quasar was the most distant one known from 2011 until 2017, and is seen as it was just 745 million years after the Big Bang. It is the most distant quasar with a visual image available to be viewed by the public. (ESO/UKIDSS/SDSS)

    The first discovered object whose light exceeds 13 billion years in age, quasar ULAS J1120+0641, is 28.8 Gly away.

    9
    This artist’s concept shows the most distant quasar and the most distant supermassive black hole powering it. At a redshift of 7.54, ULAS J1342+0928 corresponds to a distance of some 29.32 billion light-years; it is the most distant quasar/supermassive black hole ever discovered. Its light arrives at our eyes today, in the radio part of the spectrum, because it was emitted just 686 million years after the Big Bang. (ROBIN DIENEL/CARNEGIE INSTITUTION FOR SCIENCE)

    However, quasar ULAS J1342+0928 is even farther at 29.32 Gly: our most distant black hole.

    10
    This illustration of the most distant gamma-ray burst ever detected, GRB 090423, is thought to be typical of most fast gamma-ray bursts. When one or two objects violently form a black hole, such as from a neutron star merger, a brief burst of gamma rays followed by an infrared afterglow (when we’re lucky) allows us to learn more about these events. The gamma rays from this event lasted just 10 seconds, but Nial Tanvir and his team found an infrared afterglow using the UKIRT telescope just 20 minutes after the burst, allowing them to determine a redshift (z=8.2) and distance (29.96 billion light-years) to great precision. (ESO/A. ROQUETTE)

    Gamma-ray bursts exceed even that; GRB 090423’s verified light comes from 29.96 Gly away in the distant Universe, while GRB 090429B might’ve been even farther.

    9
    Here, candidate galaxy UDFj-39546284 appears very faint and red, and from the colors it displays, it has an inferred redshift of 10, giving it an age below 500 million years and a distance greater than 31 billion light-years. Without spectroscopic confirmation, however, this and similar galaxies cannot reliably be said to have a known distance; more data is needed, as photometric redshifts are notoriously unreliable. (NASA, ESA, G. ILLINGWORTH (UNIVERSITY OF CALIFORNIA, SANTA CRUZ), R. BOUWENS (UNIVERSITY OF CALIFORNIA, SANTA CRUZ, AND LEIDEN UNIVERSITY) AND THE HUDF09 TEAM)

    Ultra-distant galaxy candidates abound, including SPT0615-JD, MACS0647-JD, and UDFj-39546284, all lacking spectroscopic confirmation.

    11
    The most distant galaxy ever discovered in the known Universe, GN-z11, has its light come to us from 13.4 billion years ago: when the Universe was only 3% its current age: 407 million years old. The distance from this galaxy to us, taking the expanding Universe into account, is an incredible 32.1 billion light-years. (NASA, ESA, AND G. BACON (STSCI))

    The most distant galaxy of all is GN-z11, located 32.1 Gly away.

    11
    The James Webb Space Telescope vs. Hubble in size (main) and vs. an array of other telescopes (inset) in terms of wavelength and sensitivity. It should be able to see the truly first galaxies, even the ones that no other observatory can see. Its power is truly unprecedented. (NASA / JWST SCIENCE TEAM)

    NASA/ESA/CSA Webb Telescope annotated

    With the 2020s promising revolutionary new observatories, these records may all soon fall.

    12
    Our deepest galaxy surveys can reveal objects tens of billions of light years away, but there are more galaxies within the observable Universe we still have yet to reveal between the most distant galaxies and the cosmic microwave background [CMB], including the very first stars and galaxies of all.

    CMB per ESA/Planck

    It is possible that the coming generation of telescopes will break all of our current distance records. (SLOAN DIGITAL SKY SURVEY (SDSS))

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    “Starts With A Bang! is a blog/video blog about cosmology, physics, astronomy, and anything else I find interesting enough to write about. I am a firm believer that the highest good in life is learning, and the greatest evil is willful ignorance. The goal of everything on this site is to help inform you about our world, how we came to be here, and to understand how it all works. As I write these pages for you, I hope to not only explain to you what we know, think, and believe, but how we know it, and why we draw the conclusions we do. It is my hope that you find this interesting, informative, and accessible,” says Ethan

     
  • richardmitnick 2:48 pm on December 19, 2019 Permalink | Reply
    Tags: "'Cotton Candy' Planet Mysteries Unravel in New Hubble Observations", , , , , NASA ESA Hubble   

    From NASA/ESA Hubble Telescope: “‘Cotton Candy’ Planet Mysteries Unravel in New Hubble Observations” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope


    From NASA/ESA Hubble Telescope

    December 19, 2019

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    Daniel Strain
    University of Colorado, Boulder, Colorado
    daniel.strain@colorado.edu

    Jessica Libby-Roberts
    University of Colorado, Boulder, Colorado
    jessica.e.roberts@colorado.edu

    Zach Berta-Thompson
    zachory.bertathompson@colorado.edu

    1
    Kepler 51 System

    About This Image

    This illustration depicts the Sun-like star Kepler 51, and three giant planets that NASA’s Kepler space telescope discovered in 2012-2014. These planets are all roughly the size of Jupiter but a tiny fraction of its mass. This means the planets have an extraordinarily low density, more like that of Styrofoam rather than rock or water, based on new Hubble Space Telescope observations. The planets may have formed much farther from their star and migrated inward. Now their puffed-up hydrogen/helium atmospheres are bleeding off into space. Eventually, much smaller planets might be left behind. The background starfield is correctly plotted as it would look if we gazed back toward our Sun from Kepler 51’s distance of approximately 2,600 light-years, along our galaxy’s Orion spiral arm. However, the Sun is too faint to be seen in this simulated naked-eye view.

    ________________________________________________________________________________
    New Type of World is Unlike Anything Found in the Solar System

    When astronomers look around the solar system, they find that planets can be made out of almost anything. Terrestrial planets like Earth, Mars, and Venus have dense iron cores and rocky mantles. The massive outer planets like Jupiter and Saturn are mostly gaseous and liquid. Astronomers can’t peel back their cloud layers to look inside, but their composition is deduced by comparing the planet’s mass (as calculated from its orbital motion) to its size. The result is that Jupiter has the density of water, and Saturn has an even lower density (it could float in a huge bathtub). These gas giants are just 1/5th the density of rocky Earth.

    Now astronomers have uncovered a completely new class of planet unlike anything found in our solar system. Rather than a “terrestrial” or “gas giant” they might better be called “cotton candy” planets because their density is so low. These planets are so bloated they are nearly the size of Jupiter, but are just 1/100th of its mass. Three of them orbit the Sun-like star Kepler 51, located approximately 2,600 light-years away.

    The puffed-up planets might represent a brief transitory phase in planet evolution, which would explain why we don’t see anything like them in the solar system. The planets may have formed much farther from their star and migrated inward. Now their low-density hydrogen/helium atmospheres are bleeding off into space. Eventually, much smaller planets might be left behind.

    ________________________________________________________________________________

    “Super-Puffs” may sound like a new breakfast cereal. But it’s actually the nickname for a unique and rare class of young exoplanets that have the density of cotton candy. Nothing like them exists in our solar system.

    New data from NASA’s Hubble Space Telescope have provided the first clues to the chemistry of two of these super-puffy planets, which are located in the Kepler 51 system. This exoplanet system, which actually boasts three super-puffs orbiting a young Sun-like star, was discovered by NASA’s Kepler space telescope in 2012. However, it wasn’t until 2014 when the low densities of these planets were determined, to the surprise of many.

    The recent Hubble observations allowed a team of astronomers to refine the mass and size estimates for these worlds — independently confirming their “puffy” nature. Though no more than several times the mass of Earth, their hydrogen/helium atmospheres are so bloated they are nearly the size of Jupiter. In other words, these planets might look as big and bulky as Jupiter, but are roughly a hundred times lighter in terms of mass.

    How and why their atmospheres balloon outwards remains unknown, but this feature makes super-puffs prime targets for atmospheric investigation. Using Hubble, the team went looking for evidence of components, notably water, in the atmospheres of the planets, called Kepler-51 b and 51 d. Hubble observed the planets when they passed in front of their star, aiming to observe the infrared color of their sunsets. Astronomers deduced the amount of light absorbed by the atmosphere in infrared light. This type of observation allows scientists to look for the telltale signs of the planets’ chemical constituents, such as water.

    To the amazement of the Hubble team, they found the spectra of both planets not to have any telltale chemical signatures. They attribute this result to clouds of particles high in their atmospheres. “This was completely unexpected,” said Jessica Libby-Roberts of the University of Colorado, Boulder, “we had planned on observing large water absorption features, but they just weren’t there. We were clouded out!” However, unlike Earth’s water-clouds, the clouds on these planets may be composed of salt crystals or photochemical hazes, like those found on Saturn’s largest moon, Titan.

    These clouds provide the team with insight into how Kepler-51 b and 51 d stack up against other low-mass, gas-rich planets outside of our solar system. When comparing the flat spectra of the super-puffs against the spectra of other planets, the team was able to support the hypothesis that cloud/haze formation is linked to the temperature of a planet — the cooler a planet is, the cloudier it becomes.

    The team also explored the possibility that these planets weren’t actually super-puffs at all. The gravitational pull among the planets creates slight changes to their orbital periods, and from these timing effects planetary masses can be derived. By combining the variations in the timing of when a planet passes in front of its star (an event called a transit) with those transits observed by the Kepler space telescope, the team better constrained the planetary masses and dynamics of the system. Their results agreed with previous measured ones for Kepler-51 b. However, they found that Kepler-51 d was slightly less massive (or the planet was even more puffy) than previously thought.

    In the end, the team concluded that the low densities of these planets are in part a consequence of the young age of the system, a mere 500 million years old, compared to our 4.6-billion-year-old Sun. Models suggest these planets formed outside of the star’s “snow line,” the region of possible orbits where icy materials can survive. The planets then migrated inward, like a string of railroad cars.

    Now, with the planets much closer to the star, their low-density atmospheres should evaporate into space over the next few billion years. Using planetary evolution models, the team was able to show that Kepler-51 b, the planet closest to the star, will one day (in a billion years) look like a smaller and hotter version of Neptune, a type of planet that is fairly common throughout the Milky Way. However, it appears that Kepler-51 d, which is farther from the star, will continue to be a low-density oddball planet, though it will both shrink and lose some small amount of atmosphere. “This system offers a unique laboratory for testing theories of early planet evolution,” said Zach Berta-Thompson of the University of Colorado, Boulder.

    The good news is that all is not lost for determining the atmospheric composition of these two planets. NASA’s upcoming James Webb Space Telescope, with its sensitivity to longer infrared wavelengths of light, may be able to peer through the cloud layers. Future observations with this telescope could provide insight as to what these cotton candy planets are actually made of. Until then, these planets remain a sweet mystery.

    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 Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

    ESA50 Logo large

    AURA Icon

     
  • richardmitnick 1:19 pm on November 20, 2019 Permalink | Reply
    Tags: , , , , , NASA ESA Hubble   

    From NASA/ESA Hubble Telescope: “Hubble Studies Gamma-Ray Burst with the Highest Energy Ever Seen” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope


    From NASA/ESA Hubble Telescope

    November 20, 2019

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    Andrew Levan
    Institute for Mathematics, Astrophysics and Particle Physics, Radboud University, The Netherlands
    +44 7714250373
    a.levan@astro.ru.nl

    1
    NASA, ESA M. Kornmesser

    Mega-Blast From The Past Came From Distant Galaxy.

    NASA’s Hubble Space Telescope has given astronomers a peek at the location of the most energetic outburst ever seen in the universe—a blast of gamma-rays a trillion times more powerful than visible light. That’s because in a few seconds the gamma-ray burst (GRB) emitted more energy than the Sun will provide over its entire 10-billion year life.

    In January 2019, an extremely bright and long-duration GRB was detected by a suite of telescopes, including NASA’s Swift and Fermi telescopes, as well as by the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes on the Canary islands. Follow-up observations were made with Hubble to study the environment around the GRB and find out how this extreme emission is produced.

    NASA Neil Gehrels Swift Observatory

    NASA/Fermi Gamma Ray Space Telescope

    MAGIC Čerenkov telescopes at the Observatorio del Roque de los Muchachos (Garfia, La Palma, Spain)), Altitude 2,396 m (7,861 ft)

    “Hubble’s observations suggest that this particular burst was sitting in a very dense environment, right in the middle of a bright galaxy 5 billion light years away. This is really unusual, and suggests that this concentrated location might be why it produced this exceptionally powerful light,” explained one of the lead authors, Andrew Levan of the Institute for Mathematics, Astrophysics and Particle Physics Department of Astrophysics at Radboud University in the Netherlands.

    “Scientists have been trying to observe very high energy emission from gamma-ray bursts for a long time,” explained lead author Antonio de Ugarte Postigo of the Instituto de Astrofísica de Andalucía in Spain. “This new Hubble observation of accompanying lower-energy radiation from the region is a vital step in our understanding of gamma-ray bursts [and] their immediate surroundings.”

    The complementary Hubble observations reveal that the GRB occurred within the central region of a massive galaxy. Researchers say that this is a denser environment than typically observed (for GRBs) and could have been crucial for the generation of the very-high-energy radiation that was observed. The host galaxy of the GRB is actually one of a pair of colliding galaxies. The galaxy interactions may have contributed to spawning the outburst.

    Known as GRB 190114C, some of the radiation detected from the object had the highest energy ever observed. Scientists have been trying to observe such very high energy emission from GRBs for a long time, so this detection is considered a milestone in high-energy astrophysics, say researchers.

    Previous observations revealed that to achieve this energy, material must be emitted from a collapsing star at 99.999% the speed of light. This material is then forced through the gas that surrounds the star, causing a shock that creates the gamma-ray burst itself.

    Science paper:
    Nature

    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 Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

    ESA50 Logo large

    AURA Icon

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: