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  • richardmitnick 3:11 pm on August 22, 2019 Permalink | Reply
    Tags: "Revealing the Intimate Lives of MASSIVE Galaxies", , Astrophysics, , ,   

    From Gemini Observatory: “Revealing the Intimate Lives of MASSIVE Galaxies” 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    August 22, 2019

    Every galaxy has a story, and every galaxy has been many others in the past (unlike for humans, this is not purely metaphorical, as galaxies grow via hierarchical assembly). Generally speaking, the most massive galaxies have led the most interesting lives, often within teeming galactic metropolises where they are subject to frequent interactions with assorted neighbors. These interactions influence the structure and motions of the stars, gas, and dark matter that make up the galaxies. They also affect the growth of the supermassive black holes at the galaxies’ centers.

    Although the detailed life stories of most galaxies will remain forever uncertain, the key thematic elements may be surmised in various ways. A particularly powerful probe of a galaxy’s dynamical structure is called integral field spectroscopy (IFS), which dissects a galaxy’s light at each point within the spectrograph’s field of view. In this way, it is possible to construct a map of the motions of the stars within the galaxy and infer the distribution of the mass, both visible and invisible. IFS observations of the outskirts of a galaxy can provide insight into its global dynamics and past interactions, while IFS data on the innermost region can measure the mass of the supermassive black hole and the motions of the stars in its vicinity.

    The MASSIVE Galaxy Survey, led by Chung-Pei Ma of the University of California, Berkeley, is a major effort to uncover the internal structures and formation histories of the most massive galaxies within 350 million light years of our Milky Way. A recent study by the MASSIVE team presents high angular resolution IFS observations of 20 high-mass galaxies obtained with GMOS at Gemini North, combined with wide-field IFS data on the same galaxies from the 2.7-meter Harlan J Smith 2.7-meter Telescope telescope at McDonald Observatory in Texas.

    GEMINI/North GMOS

    NOAO Gemini North on MaunaKea, Hawaii, USA, Altitude 4,213 m (13,822 ft)

    U Texas at Austin McDonald Observatory Harlan J Smith 2.7-meter Telescope , Altitude 2,026 m (6,647 ft)

    The study, led by Berkeley graduate student Irina Ene, appears in the June issue of The Astrophysical Journal.

    The accompanying figure shows example maps of four indicators, or “moments” (called v, σ, h3 , and h4), of the stellar motions within two galaxies in the MASSIVE survey. The maps, based on the GMOS IFS data, cover the central regions of the galaxies. The figure also shows graphs of how these indicators vary with distance from the centers of these galaxies. Although both galaxies exhibit ordered central rotation, they are strikingly different in how the motions of the stars vary within the galaxy. Interestingly, for galaxies in the MASSIVE Survey, the directions of the motions of the stars in the central regions are often unaligned with the motions at large radius. This indicates complex and diverse merger histories.

    3
    Figure caption. Example distributions of the first four velocity “moments” (called v, σ, h3 and h4 ) measured from the GMOS-N IFS data for two of the MASSIVE survey galaxies. For each galaxy, the top row shows two-dimensional maps, while the bottom row shows two-sided radial profiles from Gemini/GMOS-N (magenta circles) and McDonald Observatory (green squares) data. For more information, see the study by Berkeley graduate student Irina Ene.

    As a proof of concept, the new study performs detailed dynamical modeling of the IFS data for NGC 1453, the galaxy in the sample with the fastest rotation rate. The team’s analysis reveals the amount of dark matter in this galaxy and shows how the shapes of the stars’ orbits change with radius. In addition, the team found an impressively large mass for the central black hole, more than three billion times the mass of our Sun. The MASSIVE Survey team is currently performing detailed modeling for all the rest of the galaxies in the sample. The results will provide further insight into the assembly histories of the largest galaxies in the local Universe and refine our understanding of the coevolution of galaxies and their central black holes up to the most extreme masses.

    See the full article here .


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    NOAO Gemini North on MaunaKea, Hawaii, USA, Altitude 4,213 m (13,822 ft)


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


    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 1:00 pm on August 22, 2019 Permalink | Reply
    Tags: , Astrophysics, , , , ,   

    From Symmetry: “Holography class gives students new perspective” 

    Symmetry Mag
    From Symmetry

    [I must say, nothing in this article tells me why this is An important subject for Symmetry.]

    08/22/19
    Bailey Bedford

    A holography class at the Ohio State University combines art and physics to provide a more complete picture of how we understand the world around us.

    Art and science are often seen as incompatible lenses through which to view the world. Science provides one perspective, characterized by detachment and certainty, and art provides another, characterized by emotion and unpredictability, and never the twain shall meet.

    But sometimes you need more than one perspective to understand the whole picture. Harris Kagan, an Ohio State University physics professor and collaborator on the ATLAS experiment at the Large Hadron Collider at CERN, proves this in his classes about the art and science of holography.

    The word “holography” derives from two Greek words that together mean “entire picture.” A hologram is essentially a 3-D picture that is designed to provide a complete image including different perspectives and parallax—the way an object’s position appears to vary for different lines of sight.

    In physics terms, each part of a hologram records an interference pattern to recreate the light that was emitted or reflected from the subject of the image. This method allows the viewer to move around and see the object from different angles like they could if the object were on the opposite side of a window.

    “My philosophy is that art and science are really the same thing,” he says. “The techniques you use to create a new idea in science are very, very similar [to the ones used in art]. To create a new idea in art, you’re using different tools, maybe different fundamentals, but the goals are the same; the honesty is the same.”

    3
    Courtesy of Harris Kagan

    4
    Courtesy of Harris Kagan

    Marrying art and science

    Kagan has been teaching holography classes since the mid-1980s. When OSU art professor Susan Dallas-Swan saw a hologram that he had produced for display using equipment from a laboratory class he taught, she arranged for Kagan to work with an art graduate student using the medium.

    The success with the graduate student led the pair of professors to set the blueprint for the classes. Some of Kagan’s classes have been in the physics department and some in the art department, with students from a variety of backgrounds mixed together in each. Kagan teaches beginner, advanced and honors undergraduate holography courses as well as a graduate course.

    Students in the class are not required to have any background in art or physics. The classes are meant to help students explore both subjects and how they intersect with math and visual perception. They include elements usually associated with science classes, such as unsupervised time in the lab working with lasers, and elements usually associated with art classes, such as artistic critiques of the students’ work. The students perform a series of projects culminating in an original piece for an art show.

    One point the critique process drove home was that the students’ art for the class should be concept-driven, says Shreyas Muralidharan, who participated as an undergraduate majoring in electrical and computer engineering and physics. By that, Kagan meant “that you need to really be able to clearly define what you want to achieve with this piece of art,” Muralidharan says. “From a physics and more scientific background, I haven’t really been exposed to [that idea].”

    Muralidharan, now a graduate student, says that Kagan would often challenge students to simplify the language in their explanations of their pieces and processes. Asking the students to explain concepts in simple terms ensured they actually understood them—a practice that he says remains useful in giving scientific presentations.

    Muralidharan says that idea encouraged him to think outside the box in his science classes as well. “A lot of the time, you can get stuck in the method of thinking in math,” he says. “We think of integrals, numbers, probability. And you kind of step back, and you realize that maybe you don’t have a good intuition for what’s actually happening.”

    Both art students and physics students benefited from the class, Muralidharan says. “I think talking to each other across that bridge helped solidify concepts.”

    Beyond the classroom

    Kagan estimates that between 2000 and 3000 students have gone through his classes. Those students have gone on to a wide variety of careers.

    “What comes with these lessons is a perspective with which to do art or to do science—a perspective with which you understand your role in the universe,” Kagan says.

    Jeff Hazelden, who took Kagan’s classes as a photography major, says Kagan’s classes introduced him to characteristics of light that are still useful in his career as a photographer and art teacher. He says he also uses parts of Kagan’s structured format for artistic critiques with his students that are new to the critique process.

    Katherine Hanlon, another former photography major, now works as a medical imaging specialist. She helps identify skin diseases by taking specialized photos using lasers and 3-D modeling. Kagan’s class introduced her to important aspects of those techniques.

    “I look back and realize that a lot of what I ended up doing in my career and my skill level and knowledge level was influenced specifically by this class,” Hanlon says. “I think it was easily the most important class I ever took in any of my education.”

    See the full article here .


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    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 12:38 pm on August 22, 2019 Permalink | Reply
    Tags: , , Astrophysics, , , ,   

    From ALMA: “ALMA Shows What’s Inside Jupiter’s Storms” 

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

    From ALMA

    22 August, 2019

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Iris Nijman
    Public Information Officer
    National Radio Astronomy Observatory Charlottesville, Virginia – USA
    Cell phone: +1 (434) 249 3423
    Email: alma-pr@nrao.edu

    1
    Radio image of Jupiter made with ALMA. Bright bands indicate high temperatures and dark bands low temperatures. The dark bands correspond to the zones on Jupiter, which are often white at visible wavelengths. The bright bands correspond to the brown belts on the planet. This image contains over 10 hours of data, so fine details are smeared by the planet’s rotation. Credit: ALMA (ESO/NAOJ/NRAO), I. de Pater et al.; NRAO/AUI NSF, S. Dagnello

    Swirling clouds, big colorful belts, giant storms. The beautiful and incredibly turbulent atmosphere of Jupiter has been showcased many times. But what is going on below the clouds? What is causing the many storms and eruptions that we see on the ‘surface’ of the planet? However, to study this, visible light is not enough. We need to study Jupiter using radio waves.

    New radio wave images made with the Atacama Large Millimeter/submillimeter Array (ALMA) provide a unique view of Jupiter’s atmosphere down to fifty kilometers below the planet’s visible (ammonia) cloud deck.

    “ALMA enabled us to make a three-dimensional map of the distribution of ammonia gas below the clouds. And for the first time, we were able to study the atmosphere below the ammonia cloud layers after an energetic eruption on Jupiter,” said Imke de Pater of the University of California, Berkeley (EE. UU.).

    The atmosphere of giant Jupiter is made out of mostly hydrogen and helium, together with trace gases of methane, ammonia, hydrosulfide, and water. The top-most cloud layer is made up of ammonia ice. Below that is a layer of solid ammonia hydrosulfide particles, and deeper still, around 80 kilometers below the upper cloud deck, there likely is a layer of liquid water. The upper clouds form the distinctive brown belts and white zones seen from Earth.

    Many of the storms on Jupiter take place inside those belts. They can be compared to thunderstorms on Earth and are often associated with lightning events. Storms reveal themselves in visible light as small bright clouds, referred to as plumes. These plume eruptions can cause a major disruption of the belt, which can be visible for months or years.

    The ALMA images were taken a few days after amateur astronomers observed an eruption in Jupiter’s South Equatorial Belt in January 2017. A small bright white plume was visible first, and then a large-scale disruption in the belt was observed that lasted for weeks after the eruption.

    De Pater and her colleagues used ALMA to study the atmosphere below the plume and the disrupted belt at radio wavelengths and compared these to UV-visible light and infrared images made with other telescopes at approximately the same time.

    “Our ALMA observations are the first to show that high concentrations of ammonia gas are brought up during an energetic eruption,” said de Pater. “The combination of observations simultaneously at many different wavelengths enabled us to examine the eruption in detail. Wich led us to confirm the current theory that energetic plumes are triggered by moist convection at the base of water clouds, which are located deep in the atmosphere. The plumes bring up ammonia gas from deep in the atmosphere to high altitudes, well above the main ammonia cloud deck,” she added.

    “These ALMA maps at millimeter wavelengths complement the maps made with the National Science Foundation’s Very Large Array in centimeter wavelengths,” said Bryan Butler of the National Radio Astronomy Observatory.

    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)

    “Both maps probe below the cloud layers seen at optical wavelengths and show ammonia-rich gases rising into and forming the upper cloud layers (zones), and ammonia-poor air sinking down (belts).”

    “The present results show superbly what can be achieved in planetary science when an object is studied with various observatories and at various wavelengths”. Explains Eric Villard, an ALMA astronomer part of the research team. “ALMA, with its unprecedented sensitivity and spectral resolution at radio wavelengths, worked together successfully with other major observatories around the world, to provide the data to allow a better understanding of the atmosphere of Jupiter.”

    3
    Flat map of Jupiter in radio waves with ALMA (top) and visible light with the Hubble Space Telescope (bottom). The eruption in the South Equatorial Belt is visible in both images. Credit: ALMA (ESO/NAOJ/NRAO), I. de Pater et al.; NRAO/AUI NSF, S. Dagnello; NASA/Hubble

    Science paper:
    First ALMA Millimeter Wavelength Maps of Jupiter, with a Multi-Wavelength Study of Convection
    https://arxiv.org/pdf/1907.11820.pdf

    See the full article here .

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    The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Academia Sinica (AS) in Taiwan.

    ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI) and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

    NRAO Small
    ESO 50 Large

     
  • richardmitnick 10:47 am on August 22, 2019 Permalink | Reply
    Tags: A triplet of Earth-sized planet candidates orbiting a star just 12 light-years away a new study has found., , Astrophysics, , , , , M dwarf star GJ 1061   

    From European Southern Observatory via Discover: “Three New Exoplanets Have Been Discovered Around a Nearby Star” 

    ESO 50 Large

    From European Southern Observatory

    via

    DiscoverMag

    Discover Magazine

    August 21, 2019
    Mara Johnson-Groh

    There is a triplet of Earth-sized planet candidates orbiting a star just 12 light-years away, a new study has found. And one appears to be in the habitable zone.

    All three candidates are thought to be at least 1.4 to 1.8 times the mass of Earth, and orbit the star every three to 13 days, which would put the entire system well within Mercury’s 88 day orbit of the Sun. The planet orbiting the star every 13 days, dubbed planet d, is most interesting to scientists — it falls within the star’s habitable zone where liquid water could exist on the surface.

    Exploring Our Neighborhood

    “We are now one step closer [to] getting a census of rocky planets in the solar neighborhood,” said Ignasi Ribas, co-author on the new paper [MNRAS] and researcher at the Institute of Space Sciences in Barcelona, Spain.

    The planets’ host is GJ 1061, a type of low-mass star called an M dwarf that is the 20th nearest star to the Sun. The star is similar to Proxima Centauri, the star closest to Earth, which was discovered to host a planet in 2016. GJ 1061, however, shows less violent stellar activity, suggesting that it might currently provide a safer environment for life than Proxima Centauri.

    But to assess habitability, a star’s whole history needs to be accounted for and M dwarf stars could have had stronger activity levels in the past and also have much longer lifetimes than Sun-like stars. This means that a close-orbit planet, like planet d, may have spent many millions of years being blasted by intense radiation from its star, so it may not retain a life-sustaining atmosphere.

    The new planets were discovered with the radial velocity method — a technique that uses tiny wobbles in a star’s orbit to revel the gravitational presence of exoplanets.

    Radial Velocity Method-Las Cumbres Observatory

    Radial velocity Image via SuperWasp http:// http://www.superwasp.org/exoplanets.htm

    This technique typically reveals giant exoplanets close to their host star, but increasingly, this method is being used in long-term campaigns to reveal smaller exoplanets.

    Using the HARPS instrument on the 3.6-meter telescope at the European Southern Observatory in La Silla, Chile [below], astronomers observed the star over 54 nights from July to September in 2018.

    ESO/HARPS at La Silla


    ESO 3.6m telescope & HARPS at Cerro LaSilla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    The star was one target of a larger campaign called the Red Dot project, which since 2017 has surveyed small nearby stars to look for terrestrial planets like Earth.

    ESO Pale Red Dot project

    The data showed the signatures of three, and possibly four, candidate planets. The scientists suspect the fourth signal is just stellar activity — not a real planet. But after calculating the remaining three planets’ orbits, the scientists could not rule out an additional, unseen fourth planet. This undiscovered planet would have a much longer orbit, so further observations would be need to determine if there really is a fourth planet farther out.

    See the full article here .


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    Visit ESO in Social Media-

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    Twitter

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    ESO Bloc Icon

    ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre EEuropean Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO/Cerro LaSilla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO VLT at Cerro Paranal in the Atacama Desert

    ESO VLT 4 lasers on Yepun

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT.

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

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. a large project known as the Cherenkov Telescope Array, composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison, and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev

     
  • richardmitnick 9:09 am on August 21, 2019 Permalink | Reply
    Tags: AEON-Astronomical Event Observatory Network, , Astrophysics, , ,   

    From NOAO: “First Night of AEON Queue Operations on SOAR a Success!” 

    NOAO Banner

    From NOAO

    1

    Cesar Briceno, Jay Elias (NOAO)

    The Astronomical Event Observatory Network (AEON), a collaboration between Las Cumbres Observatory (LCO), NOAO, SOAR and Gemini, is aimed at building an ecosystem of world-class telescope facilities for the follow up of transients and time-domain astronomy, in preparation for the LSST era.

    LCOGT Las Cumbres Observatory Global Telescope Network, Haleakala Hawaii, USA, Elevation 10,023 ft (3,055 m)


    SART telescope (SOAR) situated on Cerro Pachón, just to the southeast of Cerro Tololo on the AURA site at an altitude of 2,700 meters (8,775 feet) above sea level


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

    LSST

    LSST Camera, built at SLAC



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


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

    The night of 6 August 2019 set a milestone for the project, as the first of 20 nights scheduled on the SOAR telescope this semester in AEON-queue mode. The night was successful, with a total of 10 different targets studied under excellent observing conditions. Additional queue-scheduled observing nights are anticipated at a rate of 3-4 per month for the remainder of the 2019B semester.

    Over this semester, SOAR’s AEON-scheduled queue will carry out observations that have been approved through the standard NOAO TAC process. The approved programs, eight regular programs and four Target-of-Opportunity programs, pursue diverse science cases, ranging from the characterization and study of Near Earth Objects, microlensing events, young supernovae, RR Lyrae stars in ultra-faint dwarf galaxies, solar-like pre-main sequence stars, to the follow up of Galactic transients and gravitational wave events.

    AEON builds on the infrastructure of the existing network of small telescopes run by LCO to incorporate 4-m and 8-m class telescopes. The underlying idea is to create an integrated “follow-up” ecosystem, as outlined in the figure below.

    3
    The AEON concept. The red rectangle on the right highlights the portions currently under development and testing. SOAR is the pathfinder facility for bringing other telescopes into a highly automated system, running unsupervised software, that generates a dynamic and flexible schedule roughly every 15 minutes.

    SOAR’s Goodman instrument is currently available through the AEON queue in a subset of modes: imaging with the VR, SDSS-g, SDSS-r, SDSS-i filters, and spectroscopy with the red camera, 400 line grating and 1 arcsecond slit. Users can submit their targets at any time during the semester, through the LCO Observing Portal or with custom software that connects to LCO via their API. On an AEON night, the observing schedule is downloaded from LCO and executed by software that runs both the telescope and the Goodman instrument; guide star and on-slit target acquisition (for spectroscopic observations) are the only steps still carried out manually. Users can obtain the status of their observations and retrieve their raw data through the LCO Observing Portal. Data reduction can be carried out in an automated way using the Goodman Spectroscopic Data Reduction Pipeline. Further information on observing with AEON is available at the LCO-AEON web site.

    SOAR intends to expand the range of Goodman configurations available in queue mode and to eventually add additional instruments such as TripleSpec 4.1. The underlying objective is to provide flexible observing in an era of complex observing requirements ranging from large survey programs to focused time-domain programs.

    To learn more: Interested SOAR-AEON users, including those affiliated with other SOAR partners, are invited to consult future issues of Currents and calls for the proposals for additional opportunities and information. Updates on available instruments or observing configurations for the 2020A semester will be provided when the NOAO call for proposals is issued in early September. We are also very much interested in including programs from other SOAR partners in the AEON queue. Developing the AEON Network will be a major topic of discussion at the upcoming TOM Toolkit Workshop. Further information on the current status and related matters at the SOAR AEON page.

    SOAR’s success in reaching this milestone is due to the effort of a many people, including Diego Gomez and Omar Estay of NOAO and Jon Nation, Elizabeth Heinrich, and Mark Bowman of Las Cumbres Observatory. Queue operations also rely on the skill and efficiency of the regular SOAR operators. Funding for much of this work was provided by supplementary funding from the National Science Foundation.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    NOAO is the US national research & development center for ground-based night time astronomy. In particular, NOAO is enabling the development of the US optical-infrared (O/IR) System, an alliance of public and private observatories allied for excellence in scientific research, education and public outreach.

    Our core mission is to provide public access to qualified professional researchers via peer-review to forefront scientific capabilities on telescopes operated by NOAO as well as other telescopes throughout the O/IR System. Today, these telescopes range in aperture size from 2-m to 10-m. NOAO is participating in the development of telescopes with aperture sizes of 20-m and larger as well as a unique 8-m telescope that will make a 10-year movie of the Southern sky.

    In support of this mission, NOAO is engaged in programs to develop the next generation of telescopes, instruments, and software tools necessary to enable exploration and investigation through the observable Universe, from planets orbiting other stars to the most distant galaxies in the Universe.

    To communicate the excitement of such world-class scientific research and technology development, NOAO has developed a nationally recognized Education and Public Outreach program. The main goals of the NOAO EPO program are to inspire young people to become explorers in science and research-based technology, and to reach out to groups and individuals who have been historically under-represented in the physics and astronomy science enterprise.

    The National Optical Astronomy Observatory is proud to be a US National Node in the International Year of Astronomy, 2009.

    About Our Observatories:
    Kitt Peak National Observatory (KPNO)

    Kitt Peak

    Kitt Peak National Observatory (KPNO) has its headquarters in Tucson and operates the Mayall 4-meter, the 3.5-meter WIYN , the 2.1-meter and Coudé Feed, and the 0.9-meter telescopes on Kitt Peak Mountain, about 55 miles southwest of the city.

    Cerro Tololo Inter-American Observatory (CTIO)

    NOAO Cerro Tolo

    The Cerro Tololo Inter-American Observatory (CTIO) is located in northern Chile. CTIO operates the 4-meter, 1.5-meter, 0.9-meter, and Curtis Schmidt telescopes at this site.

    The NOAO System Science Center (NSSC)

    NOAO Gemini North on MaunaKea, Hawaii, USA, Altitude 4,213 m (13,822 ft)


    Gemini North

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

    The NOAO System Science Center (NSSC) at NOAO is the gateway for the U.S. astronomical community to the International Gemini Project: twin 8.1 meter telescopes in Hawaii and Chile that provide unprecedented coverage (northern and southern skies) and details of our universe.

    NOAO is managed by the Association of Universities for Research in Astronomy under a Cooperative Agreement with the National Science Foundation.

     
  • richardmitnick 8:39 am on August 21, 2019 Permalink | Reply
    Tags: , Astrophysics, , , , ,   

    From University of Washington: “James Webb Space Telescope could begin learning about TRAPPIST-1 atmospheres in a single year, study indicates” 

    U Washington

    From University of Washington

    August 13, 2019
    Peter Kelley

    New research from astronomers at the University of Washington uses the intriguing TRAPPIST-1 planetary system as a kind of laboratory to model not the planets themselves, but how the coming James Webb Space Telescope might detect and study their atmospheres, on the path toward looking for life beyond Earth.

    1
    New research from UW astronomers models how telescopes such as the James Webb Space Telescope will be able to study the planets of the intriguing TRAPPIST-1 system.NASA

    NASA/ESA/CSA Webb Telescope annotated

    The study, led by Jacob Lustig-Yaeger, a UW doctoral student in astronomy, finds that the James Webb telescope, set to launch in 2021, might be able to learn key information about the atmospheres of the TRAPPIST-1 worlds even in its first year of operation, unless — as an old song goes — clouds get in the way.

    “The Webb telescope has been built, and we have an idea how it will operate,” said Lustig-Yaeger. “We used computer modeling to determine the most efficient way to use the telescope to answer the most basic question we’ll want to ask, which is: Are there even atmospheres on these planets, or not?”

    His paper, “The Detectability and Characterization of the TRAPPIST-1 Exoplanet Atmospheres with JWST,” was published online in June in The Astronomical Journal.

    The TRAPPIST-1 system, 39 light-years — or about 235 trillion miles — away in the constellation of Aquarius, interests astronomers because of its seven orbiting rocky, or Earth-like, planets. Three of these worlds are in the star’s habitable zone — that swath of space around a star that is just right to allow liquid water on the surface of a rocky planet, thus giving life a chance.

    The star, TRAPPIST-1, was much hotter when it formed than it is now, which would have subjected all seven planets to ocean, ice and atmospheric loss in the past.

    “There is a big question in the field right now whether these planets even have atmospheres, especially the innermost planets,” Lustig-Yaeger said. “Once we have confirmed that there are atmospheres, then what can we learn about each planet’s atmosphere — the molecules that make it up?”

    Given the way he suggests the James Webb Space Telescope might search, it could learn a lot in fairly short time, this paper finds.

    Astronomers detect exoplanets when they pass in front of or “transit” their host star, resulting in a measurable dimming of starlight.

    Planet transit. NASA/Ames

    Planets closer to their star transit more frequently and so are somewhat easier to study. When a planet transits its star, a bit of the star’s light passes through the planet’s atmosphere, with which astronomers can learn about the molecular composition of the atmosphere.

    Lustig-Yaeger said astronomers can see tiny differences in the planet’s size when they look in different colors, or wavelengths, of light.

    “This happens because the gases in the planet’s atmosphere absorb light only at very specific colors. Since each gas has a unique ‘spectral fingerprint,’ we can identify them and begin to piece together the composition of the exoplanet’s atmosphere.”

    Lustig-Yaeger said the team’s modeling indicates that the James Webb telescope, using a versatile onboard tool called the Near-Infrared Spectrograph, could detect the atmospheres of all seven TRAPPIST-1 planets in 10 or fewer transits — if they have cloud-free atmospheres. And of course we don’t know whether or not they have clouds.

    If the TRAPPIST-1 planets have thick, globally enshrouding clouds like Venus does, detecting atmospheres might take up to 30 transits.

    “But that is still an achievable goal,” he said. “It means that even in the case of realistic high-altitude clouds, the James Webb telescope will still be capable of detecting the presence of atmospheres — which before our paper was not known.”

    Many rocky exoplanets have been discovered in recent years, but astronomers have not yet detected their atmospheres. The modeling in this study, Lustig-Yaeger said, “demonstrates that, for this TRAPPIST-1 system, detecting terrestrial exoplanet atmospheres is on the horizon with the James Webb Space Telescope — perhaps well within its primary five-year mission.”

    The team found that the Webb telescope may be able to detect signs that the TRAPPIST-1 planets lost large amounts of water in the past, when the star was much hotter. This could leave instances where abiotically produced oxygen — not representative of life — fills an exoplanet atmosphere, which could give a sort of “false positive” for life. If this is the case with TRAPPIST-1 planets, the Webb telescope may be able to detect those as well.

    Lustig-Yaeger’s co-authors, both with the UW, are astronomy professor Victoria Meadows, who is also principal investigator for the UW-based Virtual Planetary Laboratory; and astronomy doctoral student Andrew Lincowski. The work follows, in part, on previous work by Lincowski modeling possible climates for the seven TRAPPIST-1 worlds.

    “By doing this study, we have looked at: What are the best-case scenarios for the James Webb Space Telescope? What is it going to be capable of doing? Because there are definitely going to be more Earth-sized planets found before it launches in 2021.”

    The research was funded by a grant from the NASA Astrobiology Program’s Virtual Planetary Laboratory team, as part of the Nexus for Exoplanet System Science (NExSS) research coordination network.

    Lustig-Yaeger added: “It’s hard to conceive in theory of a planetary system better suited for James Webb than TRAPPIST-1.”

    See the full article here .


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  • richardmitnick 11:39 am on August 19, 2019 Permalink | Reply
    Tags: , Astrophysics, , , , , , The exoplanet LHS 3844b   

    From NASA JP-Caltech: “NASA Gets a Rare Look at a Rocky Exoplanet’s Surface” 

    From NASA JP-Caltech

    August 19, 2019

    Calla Cofield
    Jet Propulsion Laboratory, Pasadena, Calif.
    626-808-2469
    calla.e.cofield@jpl.nasa.gov

    1
    This artist’s illustration depicts the exoplanet LHS 3844b, which is 1.3 times the mass of Earth and orbits an M dwarf star. The planet’s surface may be covered mostly in dark lava rock, with no apparent atmosphere, according to observations by NASA’s Spitzer Space Telescope. Credit: NASA/JPL-Caltech/R. Hurt (IPAC)

    2
    Hot Earth LHS 3844 b in the orbit of a bright red dwarf discovered/
    3

    A new study using data from NASA’s Spitzer Space Telescope provides a rare glimpse of conditions on the surface of a rocky planet orbiting a star beyond the Sun.

    NASA/Spitzer Infrared Telescope

    The study, published today in the journal Nature, shows that the planet’s surface may resemble those of Earth’s Moon or Mercury: The planet likely has little to no atmosphere and could be covered in the same cooled volcanic material found in the dark areas of the Moon’s surface, called mare.

    Discovered in 2018 by NASA’s Transiting Exoplanet Satellite Survey (TESS) mission, planet LHS 3844b is located 48.6 light-years from Earth and has a radius 1.3 times that of Earth.

    NASA/MIT TESS replaced Kepler in search for exoplanets

    It orbits a small, cool type of star called an M dwarf – especially noteworthy because, as the most common and long-lived type of star in the Milky Way galaxy, M dwarfs may host a high percentage of the total number of planets in the galaxy.

    TESS found the planet via the transit method, which involves detecting when the observed light of a parent star dims because of a planet orbiting between the star and Earth.

    Planet transit. NASA/Ames

    Detecting light coming directly from a planet’s surface – another method – is difficult because the star is so much brighter and drowns out the planet’s light.

    But during follow-up observations, Spitzer was able to detect light from the surface of LHS 3844b.

    The planet makes one full revolution around its parent star in just 11 hours. With such a tight orbit, LHS 3844b is most likely “tidally locked,” which is when one side of a planet permanently faces the star. The star-facing side, or dayside, is about 1,410 degrees Fahrenheit (770 degrees Celsius). Being extremely hot, the planet radiates a lot of infrared light, and Spitzer is an infrared telescope. The planet’s parent star is relatively cool (though still much hotter than the planet), making direct observation of LHS 3844b’s dayside possible.

    This observation marks the first time Spitzer data have been able to provide information about the atmosphere of a terrestrial world around an M dwarf.

    The Search for Life

    By measuring the temperature difference between the planet’s hot and cold sides, the team found that there is a negligible amount of heat being transferred between the two. If an atmosphere were present, hot air on the dayside would naturally expand, generating winds that would transfer heat around the planet. On a rocky world with little to no atmosphere, like the Moon, there is no air present to transfer heat.

    “The temperature contrast on this planet is about as big as it can possibly be,” said Laura Kreidberg, a researcher at the Harvard and Smithsonian Center for Astrophysics in Cambridge, Massachusetts, and lead author of the new study. “That matches beautifully with our model of a bare rock with no atmosphere.”

    Understanding the factors that could preserve or destroy planetary atmospheres is part of how scientists plan to search for habitable environments beyond our solar system. Earth’s atmosphere is the reason liquid water can exist on the surface, enabling life to thrive. On the other hand, the atmospheric pressure of Mars is now less than 1% of Earth’s, and the oceans and rivers that once dotted the Red Planet’s surface have disappeared.

    “We’ve got lots of theories about how planetary atmospheres fare around M dwarfs, but we haven’t been able to study them empirically,” Kreidberg said. “Now, with LHS 3844b, we have a terrestrial planet outside our solar system where for the first time we can determine observationally that an atmosphere is not present.”

    Compared to Sun-like stars, M dwarfs emit high levels of ultraviolet light (though less light overall), which is harmful to life and can erode a planet’s atmosphere. They’re particularly violent in their youth, belching up a large number of flares, or bursts of radiation and particles that could strip away budding planetary atmospheres.

    The Spitzer observations rule out an atmosphere with more than 10 times the pressure of Earth’s. (Measured in units called bars, Earth’s atmospheric pressure at sea level is about 1 bar.) An atmosphere between 1 and 10 bars on LHS 3844b has been almost entirely ruled out as well, although the authors note there’s a slim chance it could exist if the stellar and planetary properties were to meet some very specific and unlikely criteria. They also argue that with the planet so close to a star, a thin atmosphere would be stripped away by the star’s intense radiation and outflow of material (often called stellar winds).

    “I’m still hopeful that other planets around M dwarfs could keep their atmospheres,” Kreidberg said. “The terrestrial planets in our solar system are enormously diverse, and I expect the same will be true for exoplanet systems.”

    A Bare Rock

    Spitzer and NASA’s Hubble Space Telescope have previously gathered information about the atmospheres of multiple gas planets, but LHS 3844b appears to be the smallest planet for which scientists have used the light coming from its surface to learn about its atmosphere (or lack thereof). Spitzer previously used the transit method to study the seven rocky worlds around the TRAPPIST-1 star (also an M dwarf) and learn about their possible overall composition; for instance, some of them likely contain water ice.

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

    The authors of the new study went one step further, using LHS 3844b’s surface albedo (or its reflectiveness) to try to infer its composition.

    The Nature study shows that LHS 3844b is “quite dark,” according to co-author Renyu Hu, an exoplanet scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California. which manages the Spitzer Space Telescope. He and his co-authors believe the planet is covered with basalt, a kind of volcanic rock. “We know that the mare of the Moon are formed by ancient volcanism,” Hu said, “and we postulate that this might be what has happened on this planet.”

    JPL manages the Spitzer Space Telescope mission for NASA’s Science Mission Directorate in Washington. Science operations are conducted at the Spitzer Science Center at Caltech in Pasadena. Space operations are based at Lockheed Martin Space in Littleton, Colorado. Data are archived at the Infrared Science Archive housed at IPAC at Caltech. Caltech manages JPL for NASA.

    For more information on Spitzer, visit:

    http://www.nasa.gov/spitzer

    http://www.spitzer.caltech.edu/

    See the full article here .

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    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

     
  • richardmitnick 9:15 am on August 19, 2019 Permalink | Reply
    Tags: "Brookhaven Completes LSST's Digital Sensor Array", , , Astrophysics, , , , ,   

    From Brookhaven National Lab: “Brookhaven Completes LSST’s Digital Sensor Array” 

    From Brookhaven National Lab

    August 19, 2019

    Stephanie Kossman
    skossman@bnl.gov
    (631) 344-8671

    Peter Genzer,
    genzer@bnl.gov
    (631) 344-3174

    Brookhaven National Lab has finished constructing the 3.2 gigapixel “digital film” for the world’s largest camera for cosmology, physics, and astronomy.

    1
    SLAC National Accelerator Laboratory installs the first of Brookhaven’s 21 rafts that make up LSST’s digital sensor array. Photo courtesy SLAC National Accelerator Laboratory.

    After 16 years of dedicated planning and engineering, scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have completed a 3.2 gigapixel sensor array for the camera that will be used in the Large Synoptic Survey Telescope (LSST), a massive telescope that will observe the universe like never before.

    LSST

    LSST Camera, built at SLAC



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


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

    “This is the biggest charge-coupled device (CCD) array that has ever been built,” said Paul O’Connor, senior scientist at Brookhaven Lab’s instrumentation division. “It’s three billion pixels. No telescope has ever put this many sensors into one camera.”

    The digital sensor array is composed of about 200 16-megapixel sensors, divided into 21 modules called “rafts.” Each raft can function on its own, but when combined, they will view an area of sky that can fit more than 40 full moons in a single image. Researchers will stitch these images together to create a time-lapse movie of the complete visible universe accessible from Chile.

    Currently under construction on a mountaintop in Chile, LSST is designed to capture the most complete images of our universe that have ever been achieved. The project to build the telescope facility and camera is a collaborative effort among more than 30 institutions from around the world, and it is primarily funded by DOE’s Office of Science and the National Science Foundation. DOE’s SLAC National Accelerator Laboratory is leading the overall effort to construct the camera—the world’s largest camera for astronomy—while Brookhaven led the design, construction, and qualification of the digital sensor array—the “digital film” for the camera.

    “It’s the heart of the camera,” said Bill Wahl, science raft subsystem manager of the LSST project at Brookhaven Lab. “What we’ve done here at Brookhaven represents years of great work by many talented scientists, engineers, and technicians. Their work will lead to a collection of images that has never been seen before by anyone. It’s an exciting time for the project and for the Lab.”

    2
    Members of the LSST project team at Brookhaven Lab are shown with a prototype raft cryostat. In addition to the rafts, Brookhaven scientists designed and built the cryostats that hold and cool the rafts to -100° Celsius.

    Brookhaven began its LSST research and development program in 2003, with construction of the digital sensor array starting in 2014. In the time leading up to construction, Brookhaven designed and fabricated the assembly and test equipment for the science rafts used both at Brookhaven and SLAC. The Laboratory also created an entire automated production facility and cleanroom, along with production and tracking software.

    “We made sure to automate as much of the production facility as possible,” O’Connor said. “Testing a single raft could take up to three days. We were working on a tight schedule, so we had our automated facility running 24/7. Of course, out of a concern for safety, we always had someone monitoring the facility throughout the day and night.”

    Constructing the complex sensor array, which operates in a vacuum and must be cooled to -100° Celsius, is a challenge on its own. But the Brookhaven team was also tasked with testing each fully assembled raft, as well as individual sensors and electronics. Once each raft was complete, it needed to be carefully packaged in a protective environment to be safely shipped across the country to SLAC.

    The LSST team at Brookhaven completed the first raft in 2017. But soon after, they were presented with a new challenge.

    “We later discovered that design features inadvertently led to the possibility that electrical wires in the rafts could get shorted out,” O’Connor said. “The rate at which this effect was impacting the rafts was only on the order of 0.2%, but to avoid any possibility of degradation, we went through the trouble of refitting almost every raft.”

    Now, just two years after the start of raft production, the team has successfully built and shipped the final raft to SLAC for integration into the camera. This marks the end of a 16-year project at Brookhaven, which will be followed by many years of astronomical observation.

    Many of the talented team members recruited to Brookhaven for the LSST project were young engineers and technicians hired right out of graduate school. Now, they’ve all been assigned to ongoing physics projects at the Lab, such as upgrading the PHENIX detector at the Relativistic Heavy Ion Collider—a DOE Office of Science User Facility for nuclear physics research—to sPHENIX [see RHIC components below], as well as ongoing work with the ATLAS detector at CERN’s Large Hadron Collider. Brookhaven is the U.S. host laboratory for the ATLAS collaboration.

    CERN ATLAS Image Claudia Marcelloni

    “Brookhaven’s role in the LSST camera project afforded new and exciting opportunities for engineers, technicians, and scientists in electro-optics, where very demanding specifications must be met,” Wahl said. “The multi-disciplined team we assembled did an excellent job achieving design objectives and I am proud of our time together. Watching junior engineers and scientists grow into very capable team members was extremely rewarding.”

    Brookhaven Lab will continue to play a strong role in LSST going forward. As the telescope undergoes its commissioning phase, Brookhaven scientists will serve as experts on the digital sensor array in the camera. They will also provide support during LSST’s operations, which are projected to begin in 2022.

    3
    SLAC National Accelerator Laboratory installs the first of Brookhaven’s 21 rafts that make up LSST’s digital sensor array. Photo courtesy SLAC National Accelerator Laboratory.

    “The commissioning of such a complex camera will be an exciting and challenging endeavor,” said Brookhaven physicist Andrei Nomerotski, who is leading Brookhaven’s contributions to the commissioning and operation phases of the LSST project. “After years of using artificial signal sources for the sensor characterization, we are looking forward to seeing real stars and galaxies in the LSST CCDs.”

    Once operational in the Andes Mountains, LSST will serve nearly every subset of the astrophysics community. Perhaps most importantly, LSST will enable scientists to investigate dark energy and dark matter—two puzzles that have baffled physicists for decades. It is also estimated that LSST will find millions of asteroids in our solar system, in addition to offering new information about the creation of our galaxy. The images captured by LSST will be made available to physicists and astronomers in the U.S. and Chile immediately, making LSST one of the most advanced and accessible cosmology experiments ever created. Over time, the data will be made available to the public worldwide.

    See the full article here .


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    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

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    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
    i1

     
  • richardmitnick 7:48 am on August 19, 2019 Permalink | Reply
    Tags: "How many Earth-like planets are around sun-like stars?", , Astrophysics, , , NASA Kepler and K2, ,   

    From Pennsylvania State University: “How many Earth-like planets are around sun-like stars?” 

    Penn State Bloc

    From Pennsylvania State University

    14 August 2019
    Sam Sholtis

    Media Contacts
    Eric B. Ford
    Professor of Astronomy and Astrophysics
    ebf11@psu.edu
    814- 863-5558

    Sam Sholtis
    Science Writer
    samsholtis@psu.edu
    (814) 865-1390

    1
    Artist’s impression of NASA’s Kepler space telescope, which discovered thousands of new planets. New research, using Kepler data, provides the most accurate estimate to date of how often we should expect to find Earth-like planets near sun-like stars. Credit: NASA/Ames Research Center/W. Stenzel/D. Rutter

    A new study provides the most accurate estimate of the frequency that planets that are similar to Earth in size and in distance from their host star occur around stars similar to our Sun. Knowing the rate that these potentially habitable planets occur will be important for designing future astronomical missions to characterize nearby rocky planets around sun-like stars that could support life. A paper describing the model appears August 14, 2019 in The Astronomical Journal.

    Thousands of planets have been discovered by NASA’s Kepler space telescope.

    NASA/Kepler Telescope, and K2 March 7, 2009 until November 15, 2018

    Kepler, which was launched in 2009 and retired by NASA in 2018 when it exhausted its fuel supply, observed hundreds of thousands of stars and identified planets outside of our solar system—exoplanets—by documenting transit events.*

    [On July 14, 2012, one of the spacecraft’s four reaction wheels used for pointing the spacecraft stopped turning, and completing the mission would only be possible if all other reaction wheels remained reliable. Then, on May 11, 2013, a second reaction wheel failed, disabling the collection of science data and threatening the continuation of the mission. This was the origin of the K2 misson.]

    Planet transit. NASA/Ames

    Transits events occur when a planet’s orbit passes between its star and the telescope, blocking some of the star’s light so that it appears to dim. By measuring the amount of dimming and the duration between transits and using information about the star’s properties astronomers characterize the size of the planet and the distance between the planet and its host star.

    “Kepler discovered planets with a wide variety of sizes, compositions and orbits,” said Eric B. Ford, professor of astronomy and astrophysics at Penn State and one of the leaders of the research team. “We want to use those discoveries to improve our understanding of planet formation and to plan future missions to search for planets that might be habitable. However, simply counting exoplanets of a given size or orbital distance is misleading, since it’s much harder to find small planets far from their star than to find large planets close to their star.”

    To overcome that hurdle, the researchers designed a new method to infer the occurrence rate of planets across a wide range of sizes and orbital distances. The new model simulates ‘universes’ of stars and planets and then ‘observes’ these simulated universes to determine how many of the planets would have been discovered by Kepler in each `universe.’

    “We used the final catalog of planets identified by Kepler and improved star properties from the European Space Agency’s Gaia spacecraft to build our simulations,” said Danley Hsu, a graduate student at Penn State and the first author of the paper.

    ESA/GAIA satellite

    “By comparing the results to the planets cataloged by Kepler, we characterized the rate of planets per star and how that depends on planet size and orbital distance. Our novel approach allowed the team to account for several effects that have not been included in previous studies.”

    The results of this study are particularly relevant for planning future space missions to characterize potentially Earth-like planets. While the Kepler mission discovered thousands of small planets, most are so far away that it is difficult for astronomers to learn details about their composition and atmospheres.

    “Scientists are particularly interested in searching for biomarkers—molecules indicative of life—in the atmospheres of roughly Earth-size planets that orbit in the ‘habitable-zone’ of Sun-like stars,” said Ford. “The habitable zone is a range of orbital distances at which the planets could support liquid water on their surfaces. Searching for evidence of life on Earth-size planets in the habitable zone of sun-like stars will require a large new space mission.”

    How large that mission needs to be will depend on the abundance of Earth-size planets. NASA and the National Academies of Science are currently exploring mission concepts that differ substantially in size and their capabilities. If Earth-size planets are rare, then the nearest Earth-like planets are farther away and a large, ambitious mission will be required to search for evidence of life on potentially Earth-like planets. On the other hand, if Earth-size planets are common, then there will be Earth-size exoplanets orbiting stars that are close to the sun and a relatively small observatory may be able to study their atmospheres.

    “While most of the stars that Kepler observed are typically thousands of light years away from the Sun, Kepler observed a large enough sample of stars that we can perform a rigorous statistical analysis to estimate of the rate of Earth-size planets in the habitable zone of nearby sun-like stars.” said Hsu.

    Based on their simulations, the researchers estimate that planets very close to Earth in size, from three-quarters to one-and-a-half times the size of earth, with orbital periods ranging from 237 to 500 days, occur around approximately one in six stars. Importantly, their model quantifies the uncertainty in that estimate. They recommend that future planet-finding missions plan for a true rate that ranges from as low about one planet for every 33 stars to as high as nearly one planet for every two stars.

    “Knowing how often we should expect to find planets of a given size and orbital period is extremely helpful for optimize surveys for exoplanets and the design of upcoming space missions to maximize their chance of success,” said Ford. “Penn State is a leader in bringing state-of-the-art statistical and computational methods to the analysis of astronomical observations to address these sorts of questions. Our Institute for CyberScience (ICS) and Center for Astrostatistics (CASt) provide infrastructure and support that makes these types of projects possible.”

    The Center for Exoplanets and Habitable Worlds at Penn State includes faculty and students who are involved in the full spectrum of extrasolar planet research. A Penn State team built the Habitable Zone Planet Finder, an instrument to search for low-mass planets around cool stars, which recently began science operations at the Hobby-Eberly Telescope, of which Penn State is a founding partner.

    U Texas Austin McDonald Observatory Hobby-Eberly Telescope, Altitude 2,026 m (6,647 ft)

    A second Penn State-built spectrograph is in being tested before it begins a complementary survey to discover and measure the masses of low-mass planets around sun-like stars. This study makes predictions for what such planet surveys will find and will help provide context for interpreting their results.

    In addition to Ford and Hsu, the research team includes Darin Ragozzine and Keir Ashby at Brigham Young University. The research was supported by NASA; the U.S. National Science Foundation (NSF); and the Eberly College of Science, the Department of Astronomy and Astrophysics, the Center for Exoplanets and Habitable Worlds, and the Center for Astrostatistics at Penn State. Advanced computing resources and services were provided by the Penn State Institute for CyberScience, including the NSF funded CyberLAMP cluster.

    • Kepler has been replaced by the TESS spacecraft.

    NASA/MIT TESS replaced Kepler in search for exoplanets

    TESS is designed to search for exoplanets using the transit method in an area 400 times larger than that covered by the Kepler mission.

    See the full article here .

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    Please help promote STEM in your local schools.

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    WHAT WE DO BEST

    We teach students that the real measure of success is what you do to improve the lives of others, and they learn to be hard-working leaders with a global perspective. We conduct research to improve lives. We add millions to the economy through projects in our state and beyond. We help communities by sharing our faculty expertise and research.

    Penn State lives close by no matter where you are. Our campuses are located from one side of Pennsylvania to the other. Through Penn State World Campus, students can take courses and work toward degrees online from anywhere on the globe that has Internet service.

    We support students in many ways, including advising and counseling services for school and life; diversity and inclusion services; social media sites; safety services; and emergency assistance.

    Our network of more than a half-million alumni is accessible to students when they want advice and to learn about job networking and mentor opportunities as well as what to expect in the future. Through our alumni, Penn State lives all over the world.

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  • richardmitnick 12:05 pm on August 18, 2019 Permalink | Reply
    Tags: , Astrophysics, , , , , , ,   

    From Ethan Siegel: “Ask Ethan: What Has TESS Accomplished In Its First Year Of Science Operations?” 

    From Ethan Siegel
    Aug 17, 2019

    1
    An illustration of NASA’s TESS satellite and its capabilities of imaging transiting exoplanets. Kepler has given us more exoplanets than any other mission, and it revealed them all through the transit method.

    Planet transit. NASA/Ames

    NASA/Kepler Telescope, and K2 March 7, 2009 until November 15, 2018

    With TESS, we are looking to extend our capabilities even farther, using the same method with superior equipment and techniques. (NASA)

    After Kepler but before James Webb, TESS is preparing astronomers for the coming exoplanet revolution.

    There are always new discoveries and achievements occurring in science, and certain fields have experienced recent advances that are nothing short of revolutionary. A generation ago, humanity didn’t know if stars beyond our Sun had planets around them; today, we’ve discovered thousands of star systems with planets orbiting them. Planets of varying masses orbit all types of star at a vast range of distances, and astronomers are preparing for the day where we can image Earth-sized exoplanets directly to seek signs of extraterrestrial life. Today, in a post-Kepler but pre-James Webb world, TESS is the leading exoplanet-finding mission. A year into its mission, what has it accomplished? That’s what Patreon supporter Tim Graham wants to know, asking:

    With TESS completing [the] first year of its mission, surveying the southern sky, how does it compare to Kepler?

    TESS is fundamentally different than Kepler, but what it’s found should give us all incredible hope for the 2020s.

    2
    Kepler was designed to look for planetary transits, where a large planet orbiting a star could block a tiny fraction of its light, reducing its brightness by ‘up to’ 1%. The smaller a world is relative to its parent star, the more transits you need to build up a robust signal, and the longer its orbital period, the longer you need to observe to get a detection signal that rises above the noise. Kepler successfully accomplished this for thousands of planets around stars beyond our own. (MATT OF THE ZOONIVERSE/PLANET HUNTERS TEAM)

    There are some similarities between TESS and Kepler in how both missions work.

    Both TESS and Kepler measure the light coming from a target star (or a set of target stars),
    they monitor the total light output over relatively long periods of time,
    they search for periodic dips in the overall flux from the star,
    and if the dips repeat in frequency and magnitude, both extract the radius and orbital distance for a potential candidate planet.

    This is the essence of the transit method in searching for exoplanetary candidates, and it was famously employed by Kepler over its recently-ended mission, beginning in 2009. Thanks largely to Kepler, the number of known exoplanets skyrocketed from a few dozen to many thousands in under a decade.

    3
    Today, we know of over 4,000 confirmed exoplanets, with more than 2,500 of those found in the Kepler data. These planets range in size from larger than Jupiter to smaller than Earth. Yet because of the limitations on the size of Kepler and the duration of the mission, the majority of planets are very hot and close to their star, at small angular separations. TESS has the same issue with the first planets it’s discovering: they’re preferentially hot and in close orbits. Only through dedicates, long-period observations (or direct imaging) will we be able to detect planets with longer period (i.e., multi-year) orbits. (NASA/AMES RESEARCH CENTER/JESSIE DOTSON AND WENDY STENZEL; MISSING EARTH-LIKE WORLDS BY E. SIEGEL)

    The primary mission of Kepler, however, was fundamentally different from the primary mission of TESS. While Kepler’s goal was to characterize the planetary systems of as many stars as possible in as great detail as possible, TESS is particularly concerned with finding and characterizing exoplanetary systems around the closest stars to Earth. Both of these ambitions are scientifically useful and important, but what TESS is doing doesn’t compare to Kepler at all.

    In order to accomplish the goal, Kepler’s primary mission involved the continuous observation of a small region of the sky, along one of the Milky Way’s spiral arms. These observations spanned three years, encapsulating over 100,000 stars located up to some 3,000 light-years away. Thousands of these stars were discovered to exhibit these transits: the same number you’d expect if every star possessed planets that were randomly aligned relative to our line-of-sight.

    4
    Kepler’s field-of-view contains approximately 150,000 stars, but transits have only been observed for a few thousand. In theory, nearly all of these stars should have planets, but only a small percentage of planetary systems should have good enough alignments from our perspective for a transit to be observed. (PAINTING BY JON LOMBERG, KEPLER MISSION DIAGRAM ADDED BY NASA)

    Once its primary mission ended [Kepler’s reaction wheels had failed], however, Kepler switched to an alternate goal: the K2 mission. Instead of pointing at one region of the sky for a long period of time, Kepler would observe a different region of the sky for approximately 30 days, search for transits there, and then move on to another region of sky. This led to some incredible discoveries, particularly around the smallest, coolest stars in the Universe: the M-class red dwarfs.

    The lowest-mass stars are also the smallest in physical size, meaning that even a terrestrial-like, rocky planet can block a significant fraction of the star’s light during a transit: enough to have its flux dip detected by Kepler. In addition, these exoplanets can possess very short periods, meaning that to have Earth-like temperatures on them, they’ll need to be so close that they complete a full orbit in less than a month. Many fascinating systems have been discovered and/or measured precisely by the K2 mission.

    5
    This image montage shows the Maunakea Observatories, the Kepler Space Telescope, and the night sky with various K2 fields-of-view highlighted. Inside each field-of-view there are dots inside, which point out the various planetary systems discovered and measured by the K2 mission. (KAREN TERAMURA (UHIFA); NASA/KEPLER; MILOSLAV DRUCKMÜLLER AND SHADIA HABBAL)

    The K2 mission, perhaps, could be viewed as the best testing ground for TESS, but is still fundamentally different. The Kepler telescope was designed to have a narrow field-of-view but to go relatively deep: measuring flux dips around stars up to thousands of light-years away.

    TESS, on the other hand, was designed to survey practically the entire sky, with a much wider field-of-view. It doesn’t need to go as deep, because its goal is to seek planets around the closest stars to Earth: those within just 200 light-years of us. If there’s a planet orbiting a star with the right orientation to exhibit a transit as viewed from our perspective, TESS will not only find it, but will enable scientists to determine the planet’s orbital distance and physical radius.

    6
    NASA’s TESS satellite will survey the entire sky in 16 chunks-at-a-time that are approximately 12 degrees across apiece, ranging from the galactic poles down to near the galactic equator. As a result of this surveying strategy, the polar regions see more observing time, making TESS more sensitive to smaller and more distant planets in those systems. (NASA/MIT/TESS)

    Every system where an exoplanet is found by TESS will be remarkable, regardless of what type of star it is or what types of planets are found around it. You see, the goal of TESS is not, contrary to what many people think, to find an Earth-like world at the right distance from its parent star to have liquid water (and maybe life) on its surface. Sure, that would be awfully nice, but that’s not the purpose of TESS.

    Instead, the science goal of TESS is to find candidate exoplanets and candidate exoplanetary systems where future observatories ⁠ — like the James Webb Space Telescope ⁠ — can try to take detailed measurements of the planets themselves. This would include the capacity for measuring the atmospheric contents during transit, searching for potential biosignatures, or even, if we get lucky, the possibility of direct exoplanet imaging.

    7
    Hundreds of candidate planets have been discovered so far in the data collected and released by NASA’s Transiting Exoplanet Survey Satellite (TESS). Some of the closest worlds to be discovered by TESS will be candidates for being Earth-like and within the reach of direct imaging. (NASA/MIT/TESS)

    TESS was launched in April of 2018, and began taking its first scientific data in July of last year. It’s now been more than 12 months, which means that half of the sky (13 separate sets of observations of 27 days each) has now been observed by TESS. This coverage of the entire southern sky is unprecedented in terms of searches for nearby exoplanets, and while TESS now is turning to the northern hemisphere, let’s take a look at TESS’s discoveries so far:

    21 new exoplanets have been discovered, already confirmed by ground-based telescopes,

    ranging in size from as small as 0.80 times the size of Earth to larger than Jupiter,

    with an additional 850 candidate exoplanets that have been identified, awaiting ground-based confirmation,
    one system, Beta Pictoris, where exocomets (!) have been observed,

    and a small, super-Earth class planet orbiting very close to a Sun-like star that also possesses an enormous super- Jupiter on an extremely elliptical trajectory.

    8
    The Pi Mensae system was discovered to house an exoplanet way back in 2001: Pi Mensae b, with more than 10 Jupiter masses, and a huge difference between its closest approach (1.21 AU) and farthest distance (5.54 AU) from its parent star. TESS uncovered Pi Mensae c: a super-Earth with an orbital period of just 6.3 days. This marks the first time a nearby and distant planet with such different properties and orbits have been discovered around the same star. (NASA / MIT / TESS)

    But my favorite exoplanetary system investigated by TESS (so far) has to be the one around the nearby star HD 21749. It’s located 53 light-years away, it’s slightly smaller and less massive than our Sun (about 70% the mass and radius), and it now has two known planets around it.

    The first one discovered was HD 21749b, with 2.8 times the radius of Earth and 23.2 times the Earth’s mass. With a 36-day orbit, it should be on the warm side (about 300 °F/150 °C), slightly smaller but significantly denser than Uranus or Neptune. It is the longest-period exoplanet known within 100 light-years of Earth, and one of the best candidates in the TESS field for direct imaging.

    But the second planet, announced in April, is even better: HD 21749c was the first Earth-sized planet discovered by TESS, with Mercury-like temperatures, 90% the radius of Earth, and an orbital period of just 7.8 days.

    7
    An artist’s conception of HD 21749c, the first Earth-sized planet found by NASA’s Transiting Exoplanets Survey Satellite (TESS), as well as its sibling, HD 21749b, a warm sub-Neptune-sized world. (ROBIN DIENEL / CARNEGIE INSTITUTION FOR SCIENCE)

    There are huge advantages to what TESS is doing over what either Kepler or K2 did. Because TESS is preferentially measuring the nearest stars to us, identifying planets and planetary systems where follow-up observations will matter the most. The reason why is simple.

    1.When a planet orbits its star, it will be physically separated from it by some knowable, measurable distance.
    2.Depending on how far away the star is from us, that will correspond to an angular scale, with the planet achieving the largest angular separations from its star when it’s ¼ and ¾ of the way through its orbit relative to the moment of transit.
    3.Therefore, if you can identify the closest exoplanets with well-measured orbital parameters, you can use a high-resolution telescope equipped with a coronagraph to directly image the planet in question.

    As you may have guessed, the James Webb Space Telescope will have exactly the instrumentation and capabilities necessary to directly image many of these worlds.

    8
    The Near Infrared Camera (NIRCam) is Webb’s primary imager that will cover the infrared wavelength range 0.6 to 5 microns. NIRCam is equipped with coronagraphs, instruments that allow astronomers to take pictures of very faint objects around a central bright object, like stellar systems. NIRCam’s coronagraphs work by blocking a brighter object’s light, making it possible to view the dimmer object nearby. (LOCKHEED MARTIN)

    When it’s a bright, sunny day and you want to see an object in the sky that’s very close to the Sun, what do you do? You hold up a finger (or your whole hand) and block out the Sun, and then look for the nearby object that’s much intrinsically fainter than the Sun. This is exactly what telescopes equipped with coronagraphs do.

    With the next generation of telescopes, this will enable us to finally directly-image planets around the closest stars to us, but only if we know where, when, and how to look. This is exactly the type of information that astronomers are gaining from TESS. By the time the James Webb Space Telescope launches in 2021, TESS will have completed its first sweep of the entire sky, providing a rich suite of tantalizing targets suitable for direct imaging. Our first picture of an Earth-like world may well be close on the horizon. Thanks to TESS, we’ll know exactly where to look.

    9
    There are four known exoplanets orbiting the star HR 8799, all of which are more massive than the planet Jupiter. These planets were all detected by direct imaging taken over a period of seven years, with the periods of these worlds ranging from decades to centuries.

    Direct imaging-This false-color composite image traces the motion of the planet Fomalhaut b, a world captured by direct imaging. Credit: NASA, ESA, and P. Kalas (University of California, Berkeley and SETI Institute

    As in our Solar System, the inner planets revolve around their star more rapidly, and the outer planets revolve more slowly, as predicted by the law of gravity. With the next generation of telescopes like JWST, we may be able to measure Earth-like or super-Earth-like planets around the nearest stars to us. (JASON WANG / CHRISTIAN MAROIS)

    See the full article here .

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    “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

     
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