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  • richardmitnick 5:05 pm on June 4, 2018 Permalink | Reply
    Tags: , , , Can Exoplanets Form in a Binary Star System?, , Gemini Observatory, NOAO WIYN 3.5 meter telescope at Kitt Peak AZ USA   

    From Gemini Observatory: “Can Exoplanets Form in a Binary Star System?” 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    May 31, 2018

    1
    Artist interpretation of a close binary star system in which several planets orbit the brighter star. The fainter companion star looms brightly in the sky (upper right). A recent investigation confirms that the presence of a stellar pair does not interfere in planet formation. The study finds that approximately half of the stars harboring exoplanets are binary. Image credit: Robin Dienel, courtesy of the Carnegie Institution for Science.

    A new study using Gemini data reveals that the ratio of binary stars in Kepler’s K2 exoplanet host stars is similar to that found elsewhere in our neighborhood of the Milky Way. According to lead author Dr. Rachel Matson of NASA’s Ames Research Center, “While we have known that about 50% of all stars are binary, to confirm a similar ratio in exoplanet host stars helps set some important constraints on the formation of potential exoplanets seen by Kepler.”

    Until recently, astronomers generally focused on single exoplanet host stars, believing that planets form primarily around lone stars like our Sun. However, the research led by Matson, who’s team observed 206 star systems, demonstrates that the influence of a neighboring star does not appear to deter planet formation. The presence of a very close neighboring star produces enormous collateral effects on a planetary system, possibly ejecting planets into interstellar space, or gravitationally interfering with their formation and orbits.

    “In our sample we did not find evidence that the proximity of a companion star suppresses the formation of exoplanets, even at distances as small as 50 Astronomical Units, which is similar to the distance between the Sun and the edge of the Kuiper belt,” explained Matson.

    Dr. Steve Howell, Space Science & Astrobiology Division Chief at NASA Ames Research Center, a co-author of the study and leader of the Gemini Observatory high-resolution imaging effort, said, “We now have found that about half of the stars that host exoplanets are binary, both in the Kepler sample and now in the K2 sample, telling us we cannot ignore such systems and need to take them into account in our exoplanet studies.“

    The researchers used observations from the Gemini North and South telescopes, and the WIYN telescope using the Differential Speckle Survey Instrument (DSSI), for the high-resolution imaging of the K2 stars.

    NOAO WIYN telescope DSSI Differential Speckle Survey Instrument


    NOAO WIYN 3.5 meter telescope at Kitt Peak, AZ, USA, Altitude 2,096 m (6,877 ft)

    The paper is accepted for publication in The Astrophysical Journal.

    A preprint of the paper can be found here.

    See the full article here .


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

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    AURA Icon

    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

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  • richardmitnick 7:44 am on May 10, 2018 Permalink | Reply
    Tags: , , , , Gemini Observatory, Massive Cluster Galaxies Move in Unexpected Ways   

    From Gemini Observatory: “Massive Cluster Galaxies Move in Unexpected Ways” 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    1
    Figure 1. MS0440+02 galaxy cluster. The central galaxy is a multi-component BCG formed by six bright elliptical spheroids, all at the same redshift. This is a color composite GMOS South image (g, r, i) of the clusters. The size of the image is 2.6 x 2.6 arcmin2 (N up, E left). Credit: R. Carrasco (Gemini Observatory/AURA) and Tomás Verdugo (UNAM).

    2
    Figure 2. The slope η of the velocity dispersion profile is plotted against the central velocity dispersion σ0 for galaxies in multiple different samples. The blue points represent brightest galaxies in groups (BGGs) of high (square) and low (circles) density, while the green, red, and yellow points represent brightest cluster galaxies (BCGs) in various samples of galaxy clusters. The grey points indicate generic “early-type galaxies” (ETGs). The slope η is negative if the velocity dispersion decreases with radius and positive if it rises. Thus, massive BCGs tend to have rising profiles, with the stellar velocities responding to the cluster potential at larger radii. [Reproduced from Loubser et al. 2018, MNRAS, in press.]

    Astronomers using data from both of the Gemini Multi-Object Spectrographs (GMOS – North and South) measured the motions of stars within a sample of 32 massive elliptical cluster galaxies and found the stellar motions inconsistent with these galaxies’ solitary cousins.

    Gemini Observatory GMOS on Gemini South


    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    GEMINI/North GMOS


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

    The galaxies chosen are known as brightest cluster galaxies (BCGs) because they are the brightest members of large galaxy clusters. The international team of astronomers obtained Gemini spectra to find the relative velocities of stars within each galaxy and then determine the central stellar velocity dispersions and radial dispersion profiles for each galaxy. “This is similar to what we see in our own Solar System with the different velocities of the planets around the Sun,” said John Blakeslee, Gemini Observatory’s Head of Science. “We use the planets’ velocities to determine our Solar System’s mass distribution and it is also how we know the Sun’s mass accurately.”

    The researchers discovered a surprising variety in the shapes of the velocity dispersion profiles for the BCGs, with a large fraction showing rising dispersion profiles (Figure 2). A rising velocity dispersion profile means that the stars within these galaxies are moving faster as you look further from the galaxy’s core in response to an increasing gravitational force. In comparison, rising velocity dispersion profiles are much rarer in other massive ellipticals that are not BCGs, including many brightest galaxies in groups (BGGs).

    “You would naively think that massive elliptical galaxies are a homogeneous, well-behaved class of objects, but the most massive beasts, those in the centers of groups and clusters, continue to surprise us,” said Ilani Loubser, an astronomer at North-West University in South Africa and the lead author of the study, which has been accepted for publication in Monthly Notices of the Royal Astronomical Society. She also noted, “The quality, and the wealth of information we can measure from the GMOS spectra (even in poor weather), is remarkable!”

    BCGs tend to reside near the centers of their respective clusters, and are therefore generally embedded within extended distributions of both light and dark matter. The sample of BCGs in this study included some of the most massive known galaxies in the Universe out to a distance of about 3.2 billion light years (z ~ 0.3).

    The study also found that the slopes of the velocity dispersion profiles correlate with the galaxy luminosity, in the sense that the increase in the speed of the stars is greater in brighter BCGs, as well as BGGs. Whether the full diversity in the observed velocity dispersion profiles is consistent with standard models for the growth of massive galaxies is not yet clear. More detailed comparisons with velocity dispersion profiles in cosmological simulations are needed.

    See the full article here .

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

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    AURA Icon

    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

     
  • richardmitnick 12:53 pm on March 28, 2018 Permalink | Reply
    Tags: "Dark Matter is a No Show in Ghostly Galaxy, , , , , , Gemini Multi Object Spectrograph (GMOS) on Gemini North on Hawai‘i’s Maunakea, Gemini Observatory, Keck DIEMOS on Keck 2, , , NGC1052-DF2,   

    From Gemini and Keck: “Dark Matter is a No Show in Ghostly Galaxy” 

    NOAO

    Gemini Observatory
    Gemini Observatory

    Keck Observatory, Maunakea, Hawaii, USA.4,207 m (13,802 ft) above sea level, with Subaru and IRTF (NASA Infrared Telescope Facility). Vadim Kurland


    Keck Observatory

    Science Contacts:

    Pieter van Dokkum
    Astronomy Department
    Yale University
    pieter.vandokkum@yale.edu
    Phone: 203-432-5048

    Shany Danieli
    Astronomy Department
    Yale University
    shany.danieli@yale.edu
    Phone: 857-919-3674

    Media Contacts:

    Mari-Ela Chock
    W.M. Keck Observatory
    mchock@keck.hawaii.edu
    Phone: 808-554-0567

    Jasmin Silva
    Gemini Observatory
    jsilva@gemini.edu
    Desk: 808 974-2575

    1
    Composite color image of NGC1052-DF2 constructed from observations using the Gemini Multi Object Spectrograph (GMOS) on Gemini North on Hawai‘i’s Maunakea. The ultra-diffuse galaxy was observed using deep imaging in two filters (g’ and i’). Image credit: Gemini Observatory/NSF/AURA/Keck/Jen Miller.

    GEMINI North GMOS

    2
    Left: The ultra-diffuse galaxy is swarming with globular clusters, which hold the key to understanding this mysterious object’s origin and mass.
    Right: A closer look at one of the globular clusters within the galaxy, which are all much brighter than typical, the brightest emitting almost as much light as the brightest within the Milky Way. The spectrum, obtained by Keck Observatory shows the absorption lines used to determine the velocity of this object. Ten clusters were observed, providing the information needed to determine the mass of the galaxy, revealing its lack of dark matter. Image credit: Gemini Observatory/NSF/AURA/Keck/Jen Miller/Joy Pollard.

    Astronomers using data from the Gemini and W. M. Keck Observatories in Hawai‘i have encountered a galaxy that appears to have almost no dark matter. Since the Universe is dominated by dark matter, and it is the foundation upon which galaxies are built, “…this is a game changer,” according to Principal Investigator Pieter van Dokkum of Yale University.

    Galaxies and dark matter go hand in hand; you typically don’t find one without the other. So when researchers uncovered a galaxy, known as NGC1052-DF2, that is almost completely devoid of the stuff, they were shocked.

    “Finding a galaxy without dark matter is unexpected because this invisible, mysterious substance is the most dominant aspect of any galaxy,” said lead author Pieter van Dokkum of Yale University. “For decades, we thought that galaxies start their lives as blobs of dark matter. After that everything else happens: gas falls into the dark matter halos, the gas turns into stars, they slowly build up, then you end up with galaxies like the Milky Way. NGC1052-DF2 challenges the standard ideas of how we think galaxies form.”

    The research, published in the March 29th issue of the journal Nature, amassed data from the Gemini North and W. M. Keck Observatories, both on Maunakea, Hawai‘i, the Hubble Space Telescope, and other telescopes around the world.

    NASA/ESA Hubble Telescope

    Given its large size and faint appearance, astronomers classify NGC1052-DF2 as an ultra-diffuse galaxy, a relatively new type of galaxy that was first discovered in 2015. Ultra-diffuse galaxies are surprisingly common. However, no other galaxy of this type yet-discovered is so lacking in dark matter.

    “NGC1052-DF2 is an oddity, even among this unusual class of galaxy,” said Shany Danieli, a Yale University graduate student on the team.

    To peer even deeper into this unique galaxy, the team used the Gemini Multi Object Spectrograph (GMOS) to capture detailed images of NGC1052-DF2, assess its structure, and confirm that the galaxy had no signs of interactions with other galaxies.

    “Without the Gemini images dissecting the galaxy’s morphology we would have lacked context for the rest of the data,” said Danieli. “Also, Gemini’s confirmation that NGC1052-DF2 is not currently interacting with another galaxy will help us answer questions about the conditions surrounding its birth.”

    Van Dokkum and his team first spotted NGC1052-DF2 with the Dragonfly Telephoto Array, a custom-built telescope in New Mexico that they designed to find these ghostly galaxies.

    U Toronta Dragon Fly Telescope Array housed in New Mexico

    NGC1052-DF2 stood out in stark contrast when comparisons were made between images from the Dragonfly Telephoto Array and the Sloan Digital Sky Survey (SDSS).

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

    The Dragonfly images show a faint “blob-like” object, while SDSS data reveal a collection of relatively bright point-like sources.

    In addition to the Gemini observations, to further assess this inconsistency the team dissected the light from several of the bright sources within NGC1052-DF2 using Keck’s Deep Imaging Multi-Object Spectrograph (DEIMOS) and Low-Resolution Imaging Spectrometer (LRIS), identifying 10 globular clusters. These clusters are large compact groups of stars that orbit the galactic core.

    Keck/DEIMOS on Keck 2

    Keck LRIS

    The spectral data obtained on the Keck telescopes revealed that the globular clusters were moving much slower than expected. The slower the objects in a system move, the less mass there is in that system. The team’s calculations show that all of the mass in the galaxy could be attributed to the mass of the stars, which means there is almost no dark matter in NGC1052-DF2.

    “If there is any dark matter at all, it’s very little,” van Dokkum explained. “The stars in the galaxy can account for all of the mass, and there doesn’t seem to be any room for dark matter.”

    The team’s results demonstrate that dark matter is separable from galaxies. “This discovery shows that dark matter is real – it has its own separate existence apart from other components of galaxies,” said van Dokkum.

    NGC1052-DF2’s globular clusters and atypical structure has perplexed astronomers aiming to determine the conditions this galaxy formed under.

    “It’s like you take a galaxy and you only have the stellar halo and globular clusters, and it somehow forgot to make everything else,” van Dokkum said. “There is no theory that predicted these types of galaxies. The galaxy is a complete mystery, as everything about it is strange. How you actually go about forming one of these things is completely unknown.”

    However, researchers do have some ideas. NGC1052-DF2 resides about 65 million light years away in a collection of galaxies that is dominated by the giant elliptical galaxy NGC 1052. Galaxy formation is turbulent and violent, and van Dokkum suggests that the growth of the fledgling massive galaxy billions of years ago perhaps played a role in NGC1052-DF2’s dark-matter deficiency.

    Another idea is that a cataclysmic event within the oddball galaxy, such as the birth of myriad massive stars, swept out all the gas and dark matter, halting star formation.

    These possibilities are speculative, however, and don’t explain all of the characteristics of the observed galaxy, the researchers add.

    The team continues the hunt for more dark-matter-deficient galaxies. They are analyzing Hubble images of 23 other diffuse galaxies. Three of them appear to share similarities with NGC1052-DF2, which van Dokkum plans to follow up on in the coming months at Keck Observatory.

    “Every galaxy we knew about before has dark matter, and they all fall in familiar categories like spiral or elliptical galaxies,” van Dokkum said. “But what would you get if there were no dark matter at all? Maybe this is what you would get.”

    See the full article here .

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    The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth. The two, 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectrometer and world-leading laser guide star adaptive optics systems. Keck Observatory is a private 501(c) 3 non-profit organization and a scientific partnership of the California Institute of Technology, the University of California and NASA.

    Today Keck Observatory is supported by both public funding sources and private philanthropy. As a 501(c)3, the organization is managed by the California Association for Research in Astronomy (CARA), whose Board of Directors includes representatives from the California Institute of Technology and the University of California, with liaisons to the board from NASA and the Keck Foundation.


    Keck UCal

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

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    AURA Icon

    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

     
  • richardmitnick 3:31 pm on March 21, 2018 Permalink | Reply
    Tags: , , , , Gemini Observatory, , IGRINS   

    From Gemini: “IGRINS — A Unique Visiting Instrument at Gemini South” 

    NOAO

    Gemini Observatory
    Gemini Observatory

    March 21, 2018

    1
    IGRINS and Gemini team collaboration during a site visit to Gemini South (left to right: Hwihyun Kim, Brian Chinn, Kimberly Sokal, Greg Mace, and John Good). Image credit: Kimberly Sokal (UT Austin).

    The Immersion GRating INfrared Spectrometer (IGRINS) is a cross-dispersed near-infrared spectrograph with a resolving power of R=45,000 covering the H and K windows, from 1.45 to 2.5 microns, in a single exposure.

    2
    Immersion GRating INfrared Spectrometer (IGRINS)

    Gemini is supporting the instrument team with the installation and commission of IGRINS this month at Gemini South. As a Visiting Instrument, IGRINS is ideal because it features a single observing mode and contains no moving parts. We are grateful to the IGRINS team for agreeing to support observations with the help of Gemini staff for a total of 50 nights in semester 2018A. The IGRINS visit to Gemini is supported by the US National Science Foundation under grant AST-1702267 (PI: Gregory Mace, University of Texas at Austin), and by the Korean GMT Project of KASI. Further technical details are available in papers by Yuk et al. (2010), Park et al. (2014), and Mace et al. (2016).

    Gemini frequently hosts different Visiting Instruments at each telescope every semester, so remember to keep an eye on the calls for proposals!

    See the full article here .

    Please help promote STEM in your local schools.

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

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    AURA Icon

    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

     
  • richardmitnick 6:57 am on March 16, 2018 Permalink | Reply
    Tags: $23 Million in New Funding for Dunlap Institute Astronomers, , , , , , , Gemini Observatory, ,   

    From Dunlap: “$23 Million in New Funding for Dunlap Institute Astronomers” 

    Dunlap Institute bloc
    Dunlap Institute for Astronomy and Astrophysics

    Oct 12,2017

    Prof. Bryan Gaensler, Director
    Dunlap Institute for Astronomy & Astrophysics
    University of Toronto
    p: 416-978-6623
    e: bgaensler@dunlap.utoronto.ca
    web: http://www.dunlap.utoronto.ca/prof-bryan-gaensler/

    Prof. Suresh Sivanandam
    Dunlap Institute for Astronomy & Astrophysics
    University of Toronto
    p: 416-978-6779
    e: sivanandam@dunlap.utoronto.ca
    web: http://www.dunlap.utoronto.ca/suresh-sivanandam/

    Chris Sasaki
    Communications Coordinator | Press Officer
    Dunlap Institute for Astronomy & Astrophysics
    University of Toronto
    p: 416-978-6613
    e: csasaki@dunlap.utoronto.ca

    Astronomers from the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics have received $23 million in new funding: $10 million for the development of a radio astronomy data centre and $13 million for a new infrared spectrograph.

    The awards represent a significant milestone in the Dunlap’s mandate of developing innovative astronomical technology.

    “The Dunlap Institute’s main mission is to develop innovative new approaches to astronomy, and these two new large grants are a terrific endorsement that we’re on the right track,” says Dunlap Director Prof. Bryan Gaensler.

    “In particular, these projects superbly position the Dunlap Institute for national and international leadership. We’re excited to now flex our muscles and build big, new teams that will develop the tools and equipment needed for 21st century astronomy.”

    Gaensler, who became the Institute’s director in January 2015, will be leading a project to build the infrastructure, computing capability, and expertise needed to process the overwhelming flood of information being produced by next-generation radio telescopes. The goal is to turn raw data into images and catalogues that astronomers can use to investigate cosmic magnetism, the evolution of galaxies, cosmic explosions, and more.

    The Dunlap’s Prof. Suresh Sivanandam will develop an infrared spectrograph for the Gemini Observatory that will produce the most detailed and sensitive infrared images of the sky. With it, astronomers will be able to study some of the faintest, oldest and most distant objects in the Universe; probe the formation of stellar and planetary systems; and investigate galaxies in the early Universe.

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

    Gaensler’s project will allow Canada to play a major role in the Very Large Array Sky Survey (VLASS), an ambitious new project to make a radio map of almost the entire sky in unprecedented detail. It will also help build the Canadian capacity needed to participate in what will be the largest and most powerful radio telescope ever constructed: the Square Kilometre Array.

    SKA Square Kilometer Array

    Major partners include observatories and researchers at various universities across North America, including the US National Radio Astronomy Observatory, University of Alberta, University of Manitoba, and the National Research Council. It also includes collaborators from three significant new radio telescopes: the Canadian Hydrogen Intensity Mapping Experiment (CHIME), the Karl G. Jansky Very Large Array (VLA), and the Australian Square Kilometre Array Pathfinder (ASKAP).

    CHIME Canadian Hydrogen Intensity Mapping Experiment A partnership between the University of British Columbia McGill University, at the Dominion Radio Astrophysical Observatory in British Columbia

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

    The Gemini InfraRed Multi-Object Spectrograph (GIRMOS) is unlike any astronomical spectrograph in existence or being planned for the current suite of large telescopes, and will serve as a precursor to a spectrograph for the Thirty-Meter Telescope, now under construction in Hawaií.

    Gemini InfraRed Multi-Object Spectrograph (GIRMOS) for TMT

    TMT-Thirty Meter Telescope, proposed and now approved for Mauna Kea, Hawaii, USA4,207 m (13,802 ft) above sea level

    The spectrograph is designed for use on the 8-metre telescopes of the Gemini Observatory, the largest telescopes available to Canadian astronomers.


    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet


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

    Major partners include Dalhousie University, the National Research Council, University of British Columbia, University of Victoria, Laval University, and Saint Mary’s University.

    Plus, both projects provide ample opportunities for training students and postdoctoral fellows, and help position Canadian astronomers at the forefront of the next generation of astronomical discovery.

    The annual CFI Innovation Fund awards support transformative and innovative research or technology development in areas where Canada currently is, or has the potential to be, competitive at a global level.

    For Gaensler, the awards consist of $3.5 million from CFI, and nearly $6 million from provincial and other partners. The CFI money will flow to U of T and then on to the other partners; the rest will go directly to or stay with partners. For Sivanandam, over $5 million comes from CFI, with $7.8 million from provincial and other partners.

    The awards were announced today by the Honourable Kirsty Duncan, Minister of Science, in a ceremony at the University of Manitoba, as part of a CFI investment of more than $554 million in 117 new infrastructure projects at 61 universities, colleges and research hospitals across Canada.

    Additional notes:

    1) In addition to those noted above, Prof. Gaensler’s project also includes the following partners: McGill University, Queen’s University, University of British Columbia, Cornell University, University of Minnesota, Netherlands Institute for Radio Astronomy, University of Cape Town, University of the Western Cape, and University of California Berkeley.

    2) In addition to those partners noted above, Prof. Sivanandam’s project also includes York University and University of Manitoba.

    3) The following statement has been added to the original release: “The CFI money will flow to U of T and then on to the other partners; the rest will go directly to or stay with partners.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

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    Dunlap Institute campus

    The Dunlap Institute is committed to sharing astronomical discovery with the public. Through lectures, the web, social and new media, an interactive planetarium, and major events like the Toronto Science Festival, we are helping to answer the public’s questions about the Universe.
    Our work is greatly enhanced through collaborations with the Department of Astronomy & Astrophysics, Canadian Institute for Theoretical Astrophysics, David Dunlap Observatory, Ontario Science Centre, Royal Astronomical Society of Canada, the Toronto Public Library, and many other partners.

     
  • richardmitnick 10:45 am on February 21, 2018 Permalink | Reply
    Tags: , , , , Gemini Observatory, Shining Light on Dim Galactic Neighbors   

    From Gemini Observatory: “Shining Light on Dim Galactic Neighbors” 

    NOAO

    Gemini Observatory
    Gemini Observatory

    February 19, 2018

    By measuring the brightness of about a dozen stars, lingering just outside of our galaxy, a team of astronomers believe they have solved a nearby intergalactic mystery. The researchers exposed the identities of three ultra-faint dwarf galaxy candidates using the Gemini South telescope. The team reports that the objects appear to be loose clusters of stars, not dwarf galaxies as some had previously believed. This finding has profound ramifications on the quantity of cold dark matter around our Milky Way and, by implication, other galaxies.

    1
    On sky distribution of all known Milky Way satellite candidates with respect to the Magellanic Clouds and the neutral hydrogen gas of the Magellanic stream. For more details we refer to Nidever et al. (2010) [No link provided]. The three candidates discussed in this study are highlighted in cyan.

    2
    False color RGB image of DES1 which is the small overdensity of stars in the centre of this field. The arrows in the lower right corner have a length of 15 arcseconds.

    Using the Gemini Multi-Object Spectrograph (GMOS) at the Gemini South telescope in Chile, an international research team led by Dr. Blair C. Conn of the Australian National University studied three ultra-faint dwarf galaxy candidates, and found they were not as expected.

    Gemini Observatory GMOS on Gemini South


    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    The three ultra-faint dwarf galaxy suspects, DES1, Eridanus III, and Tucana V, located in the vicinity of the Magellanic Clouds, were studied using a wide array of classification techniques. For each, fundamental properties including age, mass, luminosity, metallicity (ratio of heavier elements) and distance were determined. Based upon these parameters, the objects have instead been classified as star clusters.

    While the brightness and metallicity are consistent with that of ultra-faint dwarf galaxies, their size and structure reveal their true nature. DES1 and Eri III are, according to the researchers, old, small, and highly elliptical stellar populations with very low metallicity. Tuc V displays a low-level excess of stars at various locations across the GMOS field without a well-defined center. This suggests that Tuc V is either a star cluster in a late stage of dissolution, or a grouping of stars associated with the Small Magellanic Cloud (SMC) halo.

    Classification of these faint objects as star clusters implies that they are not dominated by dark matter, as dwarf galaxies typically are, “and so we are still trying to define ultra-faint dwarf galaxies. Where are these smallest galaxies, what are their properties and how many are there? Answering these questions will help complete the census of Milky Way satellites and let us understand the history of our galaxy.”, says Conn.

    Conn and his team are looking into the “Missing Satellites” problem which was originally identified almost two decades ago. Based on what is called the hierarchical formation scenario, many astronomers expected a large number of dwarf satellite galaxies, each containing a high fraction of dark matter, surrounding larger galaxies like our Milky Way. However, too few such satellites have been found to account for the expected amounts of dark matter. Thus, classifying these ultra-faint objects is crucial to our understanding of dark matter in the Universe.

    Watch for a feature article on this result in the April issue of GeminiFocus.

    Abstract:
    4

    See the full article here .

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

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    AURA Icon

    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

     
  • richardmitnick 7:53 am on February 21, 2018 Permalink | Reply
    Tags: , , , , Gemini Observatory   

    From Gemini: “Placing High-Redshift Quasars in Perspective: a Gemini Near-Infrared Spectroscopic Survey” 

    NOAO

    Gemini Observatory
    Gemini Observatory

    December 12, 2017
    Principal Investigator: Ohad Shemmer, University of North Texas

    1
    At sufficiently high redshifts, several prominent quasar emission features (white solid lines) are no longer detectable in the optical spectral range, represented here by the SDSS band that extends between approximately 0.4 micron and 1.0 micron (solid black line).

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

    For the broad Hbeta and narrow [O III] lines, that are rich in diagnostic power, this occurs above redshift 1, including the era of fast quasar growth. Our GNIRS spectroscopic survey will more than triple the observed spectral band, allowing us to observe these and other emission lines in a uniform sample of 416 SDSS quasars at redshifts between 1.5 (dashed line) and 3.5. The available SDSS spectra of these sources, which cover at least the rest-frame ultraviolet C IV emission line, will enable us to establish connections between optical and ultraviolet indicators of fundamental quasar properties while more than doubling the statistics at such high redshifts.

    Program Summary:

    Our current understanding of supermassive black hole (SMBH) growth in the distant universe is compromised by the lack of key diagnostic rest-frame optical emission lines in quasar spectra. As a consequence, our view of how SMBHs and their host galaxies mutually coevolve during the peak of quasar activity is biased and incomplete. We will therefore obtain high-quality GNIRS spectroscopic observations, in the 1.0-2.5 micron band, for a uniform sample of 416 Sloan Digital Sky Survey (SDSS) quasars at redshifts between 1.5 and 3.5. This project will more than double the existing inventory of near-infrared spectra of luminous quasars at these redshifts. We will determine the most accurate and precise quasar black hole masses, accretion rates, and redshifts, and use the results to derive improved prescriptions for UV-based proxies for these parameters. We will make our data immediately available to the public, provide reduced spectra via a dedicated website, and produce a catalog of measurements and fundamental quasar properties. The improved redshifts will establish velocities of quasar outflows that interact with the host galaxies, as well as tighten measurements of small-scale quasar clustering. Furthermore, our measurements will facilitate a more complete understanding of how the rest-frame UV-optical spectral properties depend on redshift and luminosity, and test whether the physical properties of the quasar central engine evolve over cosmic time. The next generation of cosmological surveys will generate millions of optical quasar spectra, the analysis of which will greatly benefit from the prescriptions developed in this investigation, an invaluable Gemini legacy.

    Co-Investigators:

    Michael Brotherton, University of Wyoming, USA
    Ileana Andruchow, Universidad Nacional de La Plata, Argentina
    Todd Boroson, Las Cumbres Observatory, USA
    Niel Brandt, Pennsylvania State University, USA
    Sergio Cellone, Universidad Nacional de La Plata, Argentina
    Gabriel Ferrero, Universidad Nacional de La Plata, Argentina
    Sarah Gallagher, University of Western Ontario, Canada
    Richard Green, University of Arizona, USA
    Joseph Hennawi, University of California Santa Barbara, USA
    Paulina Lira, Universidad de Chile, Chile
    Adam Myers, University of Wyoming, USA
    Richard Plotkin, ICRAR-Curtin, Australia
    Gordon Richards, Drexel University, USA
    Jessie Runnoe, University of Michigan, USA
    Donald Schneider, Pennsylvania State University, USA
    Yue Shen, University of Illinois at Urbana-Champaign, USA
    Michael Strauss, Princeton University, USA
    Chris Willott, NRC Herzberg, Canada
    Beverley Wills, University of Texas at Austin, USA

    See the full article here .

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

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    AURA Icon

    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

     
  • richardmitnick 1:36 pm on January 20, 2018 Permalink | Reply
    Tags: , , , Core-collapse Supernova Rate Problem, , Gemini Observatory,   

    From Gemini: “Game Over for Supernovae Hide & Seek” 

    NOAO

    Gemini Observatory
    Gemini Observatory

    January 12, 2018

    The Core-collapse Supernova Rate Problem, or the fact that we don’t see as many core-collapse supernovae as we would expect, has a solution, thanks to research using the Gemini South telescope. The research team concludes that the majority of core collapse supernovae, exploding in luminous infrared galaxies, have previously not been found due to dust obscuration and poor spatial resolution.

    1
    SN 2013if with GeMS/GSAOI, from left to right with linear scaling: Reference image (June 2015), discovery image (April 2013) and the image subtraction. SN 2013if had a projected distance from the nucleus as small as 600 light years (200 pc), which makes it the second most nuclear CCSN discovery in a LIRG to date in the optical and near-IR after SN 2010cu.

    Core-collapse supernovae are spectacular explosions that mark the violent deaths of massive stars. An international team of astronomers, led by PhD student Erik Kool of Macquarie University in Australia, used laser guide star imaging on the Gemini South telescope to study why we don’t see as many of these core-collapse supernovae as expected.

    Gemini South Laser Guide Stars

    The study began in 2015 with the Supernova UNmasked By InfraRed detection (SUNBIRD) project which has shown that dust obscuration and limited spatial resolution can explain the small number of detections to date.

    In this, the first results of the SUNBIRD project, the team discovered three core-collapse supernovae, and one possible supernova that could not be confirmed with subsequent imaging. Remarkably, these supernovae were spotted as close as 600 light years from the bright nuclear regions of these galaxies – despite being at least 150 million light years from the Earth. “Because we observed in the near-infrared, the supernovae are less affected by dust extinction compared to optical light,” said Kool.

    According to Kool the results coming from SUNBIRD reveal that their new approach provides a powerful tool for uncovering core-collapse supernova in nuclear regions of galaxies. They also conclude that this methodology is crucial in characterizing these supernova that are invisible through other means. Kool adds, “The supernova rate problem can be resolved using the unique multi-conjugate adaptive optics capability provided by Gemini, which allows us to achieve the highest spatial resolution in order to probe very close to the nuclear regions of galaxies.” This work is published in the Monthly Notices of the Royal Astronomical Society.

    See the full article here .

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

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    AURA Icon

    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

     
  • richardmitnick 4:47 pm on December 19, 2017 Permalink | Reply
    Tags: , , , , Gemini Observatory,   

    From Gemini: “The Birth of Massive Stars Around an Unlikely Galaxy” 

    NOAO

    Gemini Observatory
    Gemini Observatory

    December 18, 2017

    Using the Gemini South telescope, researchers extracted spectra from extremely faint optical sources which they determined are nurseries of massive stars around an elliptical galaxy. Indeed, the sources were so faint that they were previously undetected and only revealed using ~4 hour exposures with the Gemini Multi-Object Spectrograph (GMOS). It is speculated that the nurseries formed as the result of a past galactic merger.

    1
    Figure 1. Gemini South spectra for six intergalactic regions around NGC 2865.

    2
    Figure 2. The red slit is the mask overlaid onto the r-band imaging. The slits are arranged in a total of 108 long slits with two short interruptions for mechanical stability of the mask. The width of each slit is 1 arcsecond.

    Using a novel observational technique, called Multi-Slit Imaging Spectroscopy (MSIS) a team, lead by Fernanda Urrutia (Universidad de La Serena and Gemini Observatory), found a new generation of star clusters around the elliptical galaxy, NGC 2865.

    “The main result of our work is that we were able to detect all the clusters of massive stars around this elliptical galaxy,” said Urrutia. “Elliptical galaxies normally don’t have enough gas to form massive stars, thus we did not expect to observe star formation inside the galaxy, much less in its surroundings.”

    The observed star-forming regions display a high quantity of heavier elements (metallicity), suggesting that these clusters were born from chemically enriched material from past generations of stars. “These high metallicities could be explained if the clusters were formed by the enriched gas coming from a merger event with at least one other spiral galaxy that formed NGC 2865,” adds Urrutia.

    “The fate of these clusters is unclear, however. We cannot discard the possibility that these objects become globular clusters in the future,” adds team member Sergio Torres-Flores from Universidad de La Serena. Globular clusters are common in halos surrounding elliptical galaxies and this work could provide a glimpse into their early evolution.

    The clusters studied, lying outside of the main galaxy, display low surface brightness in optical light and therefore can only be detected using a blind search like the MSIS technique used in this work. The six regions found by Urrutia et al. were revealed by hydrogen-alpha light emitted when surrounding gas is excited by high-energy radiation from the nearby young massive stars.

    To learn more about this discovery and the techniques see the two papers in the journal Astronomy & Astrophysics.

    See the full article here .

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

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet


    AURA Icon

    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

     
  • richardmitnick 9:00 pm on October 20, 2017 Permalink | Reply
    Tags: , , , , , Gemini Observatory, Neutron stars gravitational waves and all the gold in the universe, ,   

    From UCSC: “Neutron stars, gravitational waves, and all the gold in the universe” 

    UC Santa Cruz

    UC Santa Cruz

    14

    A UC Santa Cruz special report

    Tim Stephens

    Astronomer Ryan Foley says “observing the explosion of two colliding neutron stars” [see https://sciencesprings.wordpress.com/2017/10/17/from-ucsc-first-observations-of-merging-neutron-stars-mark-a-new-era-in-astronomy ]–the first visible event ever linked to gravitational waves–is probably the biggest discovery he’ll make in his lifetime. That’s saying a lot for a young assistant professor who presumably has a long career still ahead of him.

    2
    The first optical image of a gravitational wave source was taken by a team led by Ryan Foley of UC Santa Cruz using the Swope Telescope at the Carnegie Institution’s Las Campanas Observatory in Chile. This image of Swope Supernova Survey 2017a (SSS17a, indicated by arrow) shows the light emitted from the cataclysmic merger of two neutron stars. (Image credit: 1M2H Team/UC Santa Cruz & Carnegie Observatories/Ryan Foley)

    Carnegie Institution Swope telescope at Las Campanas, Chile, 100 kilometres (62 mi) northeast of the city of La Serena. near the north end of a 7 km (4.3 mi) long mountain ridge. Cerro Las Campanas, near the southern end and over 2,500 m (8,200 ft) high, at Las Campanas, Chile

    A neutron star forms when a massive star runs out of fuel and explodes as a supernova, throwing off its outer layers and leaving behind a collapsed core composed almost entirely of neutrons. Neutrons are the uncharged particles in the nucleus of an atom, where they are bound together with positively charged protons. In a neutron star, they are packed together just as densely as in the nucleus of an atom, resulting in an object with one to three times the mass of our sun but only about 12 miles wide.

    “Basically, a neutron star is a gigantic atom with the mass of the sun and the size of a city like San Francisco or Manhattan,” said Foley, an assistant professor of astronomy and astrophysics at UC Santa Cruz.

    These objects are so dense, a cup of neutron star material would weigh as much as Mount Everest, and a teaspoon would weigh a billion tons. It’s as dense as matter can get without collapsing into a black hole.

    THE MERGER

    Like other stars, neutron stars sometimes occur in pairs, orbiting each other and gradually spiraling inward. Eventually, they come together in a catastrophic merger that distorts space and time (creating gravitational waves) and emits a brilliant flare of electromagnetic radiation, including visible, infrared, and ultraviolet light, x-rays, gamma rays, and radio waves. Merging black holes also create gravitational waves, but there’s nothing to be seen because no light can escape from a black hole.

    Foley’s team was the first to observe the light from a neutron star merger that took place on August 17, 2017, and was detected by the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO).


    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    Caltech/MIT Advanced aLigo Hanford, WA, USA installation


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

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project

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

    ESA/eLISA the future of gravitational wave research

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

    Now, for the first time, scientists can study both the gravitational waves (ripples in the fabric of space-time), and the radiation emitted from the violent merger of the densest objects in the universe.

    3
    The UC Santa Cruz team found SSS17a by comparing a new image of the galaxy N4993 (right) with images taken four months earlier by the Hubble Space Telescope (left). The arrows indicate where SSS17a was absent from the Hubble image and visible in the new image from the Swope Telescope. (Image credits: Left, Hubble/STScI; Right, 1M2H Team/UC Santa Cruz & Carnegie Observatories/Ryan Foley)

    It’s that combination of data, and all that can be learned from it, that has astronomers and physicists so excited. The observations of this one event are keeping hundreds of scientists busy exploring its implications for everything from fundamental physics and cosmology to the origins of gold and other heavy elements.


    A small team of UC Santa Cruz astronomers were the first team to observe light from two neutron stars merging in August. The implications are huge.

    ALL THE GOLD IN THE UNIVERSE

    It turns out that the origins of the heaviest elements, such as gold, platinum, uranium—pretty much everything heavier than iron—has been an enduring conundrum. All the lighter elements have well-explained origins in the nuclear fusion reactions that make stars shine or in the explosions of stars (supernovae). Initially, astrophysicists thought supernovae could account for the heavy elements, too, but there have always been problems with that theory, says Enrico Ramirez-Ruiz, professor and chair of astronomy and astrophysics at UC Santa Cruz.

    4
    The violent merger of two neutron stars is thought to involve three main energy-transfer processes, shown in this diagram, that give rise to the different types of radiation seen by astronomers, including a gamma-ray burst and a kilonova explosion seen in visible light. (Image credit: Murguia-Berthier et al., Science)

    A theoretical astrophysicist, Ramirez-Ruiz has been a leading proponent of the idea that neutron star mergers are the source of the heavy elements. Building a heavy atomic nucleus means adding a lot of neutrons to it. This process is called rapid neutron capture, or the r-process, and it requires some of the most extreme conditions in the universe: extreme temperatures, extreme densities, and a massive flow of neutrons. A neutron star merger fits the bill.

    Ramirez-Ruiz and other theoretical astrophysicists use supercomputers to simulate the physics of extreme events like supernovae and neutron star mergers. This work always goes hand in hand with observational astronomy. Theoretical predictions tell observers what signatures to look for to identify these events, and observations tell theorists if they got the physics right or if they need to tweak their models. The observations by Foley and others of the neutron star merger now known as SSS17a are giving theorists, for the first time, a full set of observational data to compare with their theoretical models.

    According to Ramirez-Ruiz, the observations support the theory that neutron star mergers can account for all the gold in the universe, as well as about half of all the other elements heavier than iron.

    RIPPLES IN THE FABRIC OF SPACE-TIME

    Einstein predicted the existence of gravitational waves in 1916 in his general theory of relativity, but until recently they were impossible to observe. LIGO’s extraordinarily sensitive detectors achieved the first direct detection of gravitational waves, from the collision of two black holes, in 2015. Gravitational waves are created by any massive accelerating object, but the strongest waves (and the only ones we have any chance of detecting) are produced by the most extreme phenomena.

    Two massive compact objects—such as black holes, neutron stars, or white dwarfs—orbiting around each other faster and faster as they draw closer together are just the kind of system that should radiate strong gravitational waves. Like ripples spreading in a pond, the waves get smaller as they spread outward from the source. By the time they reached Earth, the ripples detected by LIGO caused distortions of space-time thousands of times smaller than the nucleus of an atom.

    The rarefied signals recorded by LIGO’s detectors not only prove the existence of gravitational waves, they also provide crucial information about the events that produced them. Combined with the telescope observations of the neutron star merger, it’s an incredibly rich set of data.

    LIGO can tell scientists the masses of the merging objects and the mass of the new object created in the merger, which reveals whether the merger produced another neutron star or a more massive object that collapsed into a black hole. To calculate how much mass was ejected in the explosion, and how much mass was converted to energy, scientists also need the optical observations from telescopes. That’s especially important for quantifying the nucleosynthesis of heavy elements during the merger.

    LIGO can also provide a measure of the distance to the merging neutron stars, which can now be compared with the distance measurement based on the light from the merger. That’s important to cosmologists studying the expansion of the universe, because the two measurements are based on different fundamental forces (gravity and electromagnetism), giving completely independent results.

    “This is a huge step forward in astronomy,” Foley said. “Having done it once, we now know we can do it again, and it opens up a whole new world of what we call ‘multi-messenger’ astronomy, viewing the universe through different fundamental forces.”

    IN THIS REPORT

    Neutron stars
    A team from UC Santa Cruz was the first to observe the light from a neutron star merger that took place on August 17, 2017 and was detected by the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO)

    5
    Graduate students and post-doctoral scholars at UC Santa Cruz played key roles in the dramatic discovery and analysis of colliding neutron stars.Astronomer Ryan Foley leads a team of young graduate students and postdoctoral scholars who have pulled off an extraordinary coup. Following up on the detection of gravitational waves from the violent merger of two neutron stars, Foley’s team was the first to find the source with a telescope and take images of the light from this cataclysmic event. In so doing, they beat much larger and more senior teams with much more powerful telescopes at their disposal.

    “We’re sort of the scrappy young upstarts who worked hard and got the job done,” said Foley, an untenured assistant professor of astronomy and astrophysics at UC Santa Cruz.

    7
    David Coulter, graduate student

    The discovery on August 17, 2017, has been a scientific bonanza, yielding over 100 scientific papers from numerous teams investigating the new observations. Foley’s team is publishing seven papers, each of which has a graduate student or postdoc as the first author.

    “I think it speaks to Ryan’s generosity and how seriously he takes his role as a mentor that he is not putting himself front and center, but has gone out of his way to highlight the roles played by his students and postdocs,” said Enrico Ramirez-Ruiz, professor and chair of astronomy and astrophysics at UC Santa Cruz and the most senior member of Foley’s team.

    “Our team is by far the youngest and most diverse of all of the teams involved in the follow-up observations of this neutron star merger,” Ramirez-Ruiz added.

    8
    Charles Kilpatrick, postdoctoral scholar

    Charles Kilpatrick, a 29-year-old postdoctoral scholar, was the first person in the world to see an image of the light from colliding neutron stars. He was sitting in an office at UC Santa Cruz, working with first-year graduate student Cesar Rojas-Bravo to process image data as it came in from the Swope Telescope in Chile. To see if the Swope images showed anything new, he had also downloaded “template” images taken in the past of the same galaxies the team was searching.

    9
    Ariadna Murguia-Berthier, graduate student

    “In one image I saw something there that was not in the template image,” Kilpatrick said. “It took me a while to realize the ramifications of what I was seeing. This opens up so much new science, it really marks the beginning of something that will continue to be studied for years down the road.”

    At the time, Foley and most of the others in his team were at a meeting in Copenhagen. When they found out about the gravitational wave detection, they quickly got together to plan their search strategy. From Copenhagen, the team sent instructions to the telescope operators in Chile telling them where to point the telescope. Graduate student David Coulter played a key role in prioritizing the galaxies they would search to find the source, and he is the first author of the discovery paper published in Science.

    10
    Matthew Siebert, graduate student

    “It’s still a little unreal when I think about what we’ve accomplished,” Coulter said. “For me, despite the euphoria of recognizing what we were seeing at the moment, we were all incredibly focused on the task at hand. Only afterward did the significance really sink in.”

    Just as Coulter finished writing his paper about the discovery, his wife went into labor, giving birth to a baby girl on September 30. “I was doing revisions to the paper at the hospital,” he said.

    It’s been a wild ride for the whole team, first in the rush to find the source, and then under pressure to quickly analyze the data and write up their findings for publication. “It was really an all-hands-on-deck moment when we all had to pull together and work quickly to exploit this opportunity,” said Kilpatrick, who is first author of a paper comparing the observations with theoretical models.

    11
    César Rojas Bravo, graduate student

    Graduate student Matthew Siebert led a paper analyzing the unusual properties of the light emitted by the merger. Astronomers have observed thousands of supernovae (exploding stars) and other “transients” that appear suddenly in the sky and then fade away, but never before have they observed anything that looks like this neutron star merger. Siebert’s paper concluded that there is only a one in 100,000 chance that the transient they observed is not related to the gravitational waves.

    Ariadna Murguia-Berthier, a graduate student working with Ramirez-Ruiz, is first author of a paper synthesizing data from a range of sources to provide a coherent theoretical framework for understanding the observations.

    Another aspect of the discovery of great interest to astronomers is the nature of the galaxy and the galactic environment in which the merger occurred. Postdoctoral scholar Yen-Chen Pan led a paper analyzing the properties of the host galaxy. Enia Xhakaj, a new graduate student who had just joined the group in August, got the opportunity to help with the analysis and be a coauthor on the paper.

    12
    Yen-Chen Pan, postdoctoral scholar

    “There are so many interesting things to learn from this,” Foley said. “It’s a great experience for all of us to be part of such an important discovery.”

    13
    Enia Xhakaj, graduate student

    IN THIS REPORT

    Scientific Papers from the 1M2H Collaboration

    Coulter et al., Science, Swope Supernova Survey 2017a (SSS17a), the Optical Counterpart to a Gravitational Wave Source

    Drout et al., Science, Light Curves of the Neutron Star Merger GW170817/SSS17a: Implications for R-Process Nucleosynthesis

    Shappee et al., Science, Early Spectra of the Gravitational Wave Source GW170817: Evolution of a Neutron Star Merger

    Kilpatrick et al., Science, Electromagnetic Evidence that SSS17a is the Result of a Binary Neutron Star Merger

    Siebert et al., ApJL, The Unprecedented Properties of the First Electromagnetic Counterpart to a Gravitational-wave Source

    Pan et al., ApJL, The Old Host-galaxy Environment of SSS17a, the First Electromagnetic Counterpart to a Gravitational-wave Source

    Murguia-Berthier et al., ApJL, A Neutron Star Binary Merger Model for GW170817/GRB170817a/SSS17a

    Kasen et al., Nature, Origin of the heavy elements in binary neutron star mergers from a gravitational wave event

    Abbott et al., Nature, A gravitational-wave standard siren measurement of the Hubble constant (The LIGO Scientific Collaboration and The Virgo Collaboration, The 1M2H Collaboration, The Dark Energy Camera GW-EM Collaboration and the DES Collaboration, The DLT40 Collaboration, The Las Cumbres Observatory Collaboration, The VINROUGE Collaboration & The MASTER Collaboration)

    Abbott et al., ApJL, Multi-messenger Observations of a Binary Neutron Star Merger

    PRESS RELEASES AND MEDIA COVERAGE


    Watch Ryan Foley tell the story of how his team found the neutron star merger in the video below. 2.5 HOURS.

    Press releases:

    UC Santa Cruz Press Release

    UC Berkeley Press Release

    Carnegie Institution of Science Press Release

    LIGO Collaboration Press Release

    National Science Foundation Press Release

    Media coverage:

    The Atlantic – The Slack Chat That Changed Astronomy

    Washington Post – Scientists detect gravitational waves from a new kind of nova, sparking a new era in astronomy

    New York Times – LIGO Detects Fierce Collision of Neutron Stars for the First Time

    Science – Merging neutron stars generate gravitational waves and a celestial light show

    CBS News – Gravitational waves – and light – seen in neutron star collision

    CBC News – Astronomers see source of gravitational waves for 1st time

    San Jose Mercury News – A bright light seen across the universe, proving Einstein right

    Popular Science – Gravitational waves just showed us something even cooler than black holes

    Scientific American – Gravitational Wave Astronomers Hit Mother Lode

    Nature – Colliding stars spark rush to solve cosmic mysteries

    National Geographic – In a First, Gravitational Waves Linked to Neutron Star Crash

    Associated Press – Astronomers witness huge cosmic crash, find origins of gold

    Science News – Neutron star collision showers the universe with a wealth of discoveries

    UCSC press release
    First observations of merging neutron stars mark a new era in astronomy

    Credits

    Writing: Tim Stephens
    Video: Nick Gonzales
    Photos: Carolyn Lagattuta
    Header image: Illustration by Robin Dienel courtesy of the Carnegie Institution for Science
    Design and development: Rob Knight
    Project managers: Sherry Main, Scott Hernandez-Jason, Tim Stephens

    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

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    Noted in the video but not in the article:

    NASA/Chandra Telescope

    NASA/SWIFT Telescope

    NRAO/Karl V Jansky VLA, on the Plains of San Agustin fifty miles west of Socorro, NM, USA

    CTIO PROMPT telescope telescope built by the University of North Carolina at Chapel Hill at Cerro Tololo Inter-American Observatory in Chilein the Chilean Andes.

    PROMPT The six domes at CTIO in Chile.

    NASA NuSTAR X-ray telescope

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    Shane Telescope at UCO Lick Observatory, UCSC

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA

    UC Santa Cruz campus
    The University of California, Santa Cruz, opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    Lick Observatory's Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building
    Lick Observatory’s Great Lick 91-centimeter (36-inch) telescope housed in the South (large) Dome of main building

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    1
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch) UCSC Lick Nickel telescope

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    5
    UCSC alumna Shelley Wright, now an assistant professor of physics at UC San Diego, discusses the dichroic filter of the NIROSETI instrument. (Photo by Laurie Hatch)

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

    UCSC is the home base for the Lick Observatory.

     
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