Cosmic Origins Newsletter, September 2016, Vol. 5, No. 2

Total Page:16

File Type:pdf, Size:1020Kb

Cosmic Origins Newsletter, September 2016, Vol. 5, No. 2 National Aeronautics and Space Administration Cosmic Origins Newsletter September 2016 Volume 5 Number 2 Summer 2016 Cosmic Origins Program Inside this Issue Update Summer 2016 Cosmic Origins Program Update ............................1 Mansoor Ahmed, COR Program Manager Hubble Reveals Stellar Fireworks in ‘Skyrocket’ Galaxy ................2 Message from the Astrophysics Division Director .........................2 Susan Neff, COR Program Chief Scientist Light Echoes Give Clues to Protoplanetary Disk ............................3 Far-IR Surveyor Study Status .............................................................5 Welcome to the September 2016 Cosmic Origins (COR) newslet- LUVOIR Study Status .........................................................................5 ter. In this issue, we provide updates on several activities relevant to Strategic Astrophysics Technology (SAT) Selections the COR Program objectives. Some of these activities are not under for ROSES-2015 ...................................................................................6 the direct purview of the program, but are relevant to COR goals, Technology Solicitations to Enable Astrophysics Discoveries ......6 therefore we try to keep you informed about their progress. Cosmic Origins Suborbital Program: Balloon Program – BETTII ................................................................7 In January 2016, Paul Hertz (Director, NASA Astrophysics) News from SOFIA ...............................................................................8 presented his plans for four large mission concept studies, GALEX Uncovers ‘Frankenstein’ Galaxy..........................................9 in preparation for the 2020 Decadal Study of Astronomy and SOFIA Pinpoints Water Vapor in Young Star ................................10 Astrophysics, and invited all interested members of the community WFIRST Update ................................................................................10 to consider nominating themselves for one (or more) of the teams. JWST Status and Progress ................................................................11 Two studies, for a Large UV-Optical-near IR mission (LUVOIR) The Complex Material Engineering of NASA’s Webb Telescope Sunshield ...............................................................12 and for a Far-Infrared Surveyor, support COR interests. The study COPAG Status ....................................................................................13 teams’ memberships were announced in March, and the teams Meet Hubble Fellow Jon Trump ......................................................14 are off and working hard. The articles byPaul Hertz and by the Upcoming Events ..............................................................................15 Community Chairs of the Far-IR Surveyor and LUVOIR studies, recommendations of the Cosmic Origins Program Analysis Group summarize expectations, plans, and activities of these study teams. (COPAG) on Probes, and reports on other COPAG activities. All four large mission study teams have been careful to include Hubble continues to make scientific breakthroughs seem significant numbers of people at early stages of their careers, as they routine, and to collect stunning images of the Universe. Demand will be the primary users of the future observatories. We introduce for Hubble observations remains very strong; the 25th call for a Hubble fellow, Dr. Jon Trump, who is currently working on proposals received over 1000 responses, with the number of orbits the connection between galaxy growth, supermassive Black Hole requested increasing significantly over last year.Spitzer recently formation, and feedback in the early universe. announced selections from its 13th call for proposals, which had In March 2016, the three Astrophysics Program Analysis the most time ever requested in a call. A third of the proposals Groups (PAGs) recommended that the Astrophysics Division were to prepare for JWST follow-up. SOFIA is operating well and sponsor several studies of possible Astrophysics Probe-class is moving ahead with its third generation instrument selection mission concepts to determine feasibility of requesting a new and fifth cycle of observing requests (results to be announced in budget line for a program of astrophysics missions larger than a October). We include highlights of a few recent science results MIDEX (but costing less than ~$1B). In July, Dr Hertz announced from operating COR missions, in boxes throughout the newsletter. his intent to support several concept studies, and in mid August a The James Webb Space Telescope (JWST) continues towards call for Astrophysics Probe Studies was released (proposals due its planned 2018 launch on time and on budget. Preparations are November 15, 2016). Dr. Hertz’s article presents his thoughts on underway for observation planning tools and proposal workshops, Astrophysics Probes. An announcement of the next MIDEX call starting this fall. We provide a quick status of JWST, as well as an is expected in September. The article by Paul Scowen presents the article about the complex manufacture of the five-layer sunshield. http://www.nasa.gov 1 The Wide-Field-Infrared Survey Telescope (WFIRST) has started Message from the Astrophysics Division Phase A development and Science Integration Teams are hard at work. We offer an article describing the WFIRST status. Director Paul Hertz, Director, Astrophysics Division, Science Mission A key part of the COR Program is managing development Directorate, NASA Headquarters of the technologies required for future COR discoveries. The Strategic Astrophysics Technology (SAT) program is designed to The NASA Science Mission Directorate (SMD) saw a major bring important technologies to a level of development that can be leadership change with the departure of Associate Administrator infused into flight missions. We provide an update on selections for for SMD, John Grunsfeld, in May 2016. Geoffrey Yoder, formerly the the SAT program. We also present a summary of combined NASA Deputy Associate Administrator for SMD, has been appointed the and NSF funding opportunities for technology development. Acting Associate Administrator for SMD. Mr. Yoder is committed The suborbital program is a major part of the technology to continuing to advance all SMD missions in formulation, maturation process, as well as an excellent training ground for development, and operations; integrating strategic planning across young instrumentalists. We present an article on the BETTII all Divisions to further advance NASA objectives and Decadal balloon payload. BETTII is a Far-Infrared interferometer, Surveys; making NASA’s technical and capability management scheduled to fly for the first time in September 2016 that will study more efficient to free up resources for more missions and science; deeply buried star-formation regions. and continuing to base NASA’s decisions firmly on community We have had several changes in the Cosmic Origins Program input and peer review. Office. Tom Griffin has moved to WFIRSTthe project office; the As I described during the NASA Town Hall at the 228th new Deputy Program Manager is Azita Valina. Harley Thronson meeting of the American Astronomical Society in San Diego, CA, is replacing Bernie Seery as Chief Technologist. We welcome them and at the July meeting of the Astrophysics Subcommittee, the to the Program Office. Astrophysics Division continues to execute a portfolio that can It’s an exciting time in Cosmic Origins, as we look to the be broadly divided into Strategic Missions, Explorer Missions, future. Please, become involved if you are not already. Research and Analysis (R&A), and other cross-cutting activities. ... We rely on our advisory committees and expert community groups Hubble Reveals Stellar Fireworks in ‘Skyrocket’ Galaxy Hubble has captured spectacular star formation in a small, nearby galaxy called Kiso 5639. The dwarf galaxy is a flattened disk, but because it is tilted edge-on, it resembles a skyrocket, with a brilliant head and a long starry tail. The intense star-formation apparent at one “end” is thought to be triggered by intergalactic gas falling onto one edge of the galaxy as it moves through space. Kiso 5369 is a rare nearby example of what occurs frequently at larger distances (where we observe the universe when it was young). Observations of the early Universe, such as Hubble’s Ultra Deep Field reveal that about 10 percent of all galaxies have these elongated shapes, dubbed “tadpoles.” Lead researcher Debra Elmegreen (Vassar College) explains: “The current thinking is that galaxies in the early universe grow [by] accreting gas from the surrounding neighborhood. It’s a stage that galaxies, including our Milky Way, must go through as they are growing up.” Studies of the nearby universe have turned up only a few of Hubble image of the “tadpole” galaxy Kiso 5639. The edge-on nearby these apparently elongated systems. The development of nearby dwarf galaxy is undergoing a burst of star formation on one edge, where tadpole galaxies has lagged behind that of their peers, which primordial gas is falling onto the disk. In this image, the pink filamentary typically take billions of years to build up to a typical spiral galaxy emission indicates ionized hydrogen gas . A burst of new stars, in a region seen today. 2700 light years across, makes the hydrogen glow. Image credit: NASA, Elmegreen’s team finds that the gas in the galaxy’s bright ESA, and D. Elmegreen (Vassar) “head” contains
Recommended publications
  • The Evolving Launch Vehicle Market Supply and the Effect on Future NASA Missions
    Presented at the 2007 ISPA/SCEA Joint Annual International Conference and Workshop - www.iceaaonline.com The Evolving Launch Vehicle Market Supply and the Effect on Future NASA Missions Presented at the 2007 ISPA/SCEA Joint International Conference & Workshop June 12-15, New Orleans, LA Bob Bitten, Debra Emmons, Claude Freaner 1 Presented at the 2007 ISPA/SCEA Joint Annual International Conference and Workshop - www.iceaaonline.com Abstract • The upcoming retirement of the Delta II family of launch vehicles leaves a performance gap between small expendable launch vehicles, such as the Pegasus and Taurus, and large vehicles, such as the Delta IV and Atlas V families • This performance gap may lead to a variety of progressions including – large satellites that utilize the full capability of the larger launch vehicles, – medium size satellites that would require dual manifesting on the larger vehicles or – smaller satellites missions that would require a large number of smaller launch vehicles • This paper offers some comparative costs of co-manifesting single- instrument missions on a Delta IV/Atlas V, versus placing several instruments on a larger bus and using a Delta IV/Atlas V, as well as considering smaller, single instrument missions launched on a Minotaur or Taurus • This paper presents the results of a parametric study investigating the cost- effectiveness of different alternatives and their effect on future NASA missions that fall into the Small Explorer (SMEX), Medium Explorer (MIDEX), Earth System Science Pathfinder (ESSP), Discovery,
    [Show full text]
  • Spherex: New NASA MIDEX All-Sky 1-5 Um Spectral Survey
    SPHEREx: New NASA MIDEX All-Sky 1-5 um Spectral Survey Designed to Explore ▪ The Origin of the Universe ▪ The Origin and History of Galaxies ▪ The Origin of Water in Planetary Systems ▪ PI Jamie Bock, CalTech The First All-Sky Near-IR Spectral Survey A Rich Legacy Archive for the Astronomy Community with 100s of Millions of Stars and Galaxies Low-Risk Implementation ▪ 2022 NASA MIDEX Launch ▪ Single Observing Mode ▪ Large Design Margins Co-I Carey Lisse, SES/SRE ▪ No Moving Optics NASA SBAG Jun 25, 2019 Copyright 2017 California Institute of Technology. U.S. Government sponsorship acknowledged. New MIDEX SPHEREx (2022-2025): All-Sky 0.8 – 5.0 µm Spectral Legacy Archives Medium- High- Accuracy Accuracy Detected Spectra Spectra Clusters > 1 billion > 100 million 10 million 25,000 All-Sky surveys demonstrate high Galaxies scientiFic returns with a lasting Main data legacy used across astronomy Sequence Brown Spectra Dust-forming Dwarfs Cataclysms For example: > 100 million 10,000 > 400 > 1,000 COBE J IRAS J Stars GALEX Asteroid WMAP & Comet Galactic Quasars Quasars z >7 Spectra Line Maps Planck > 1.5 million 1 – 300? > 100,000 PAH, HI, H2 WISE J Other More than 400,000 total citations! SPHEREx Data Products & Tools: A spectrum (0.8 to 5 micron) for every 6″ pixel on the sky Planned Data Releases Survey Data Date (Launch +) Associated Products Survey 1 1 – 8 mo S1 spectral images Survey 2 8 – 14 mo S1/2 spectral images Early release catalog Survey 3 14 – 20 mo S1/2/3 spectral images Survey 4 20 – 26 mo S1/2/3/4 spectral images Final Release
    [Show full text]
  • The Future of X-Rayastronomy
    The Future of X-rayAstronomy Keith Arnaud [email protected] High Energy Astrophysics Science Archive Research Center University of Maryland College Park and NASA’s Goddard Space Flight Center Themes Politics Efficient high resolution spectroscopy Mirrors Polarimetry Other missions Interferometry Themes Politics Efficient high resolution spectroscopy Mirrors Polarimetry Other missions Interferometry How do we get a new X-ray astronomy experiment? A group of scientists and engineers makes a proposal to a national (or international) space agency. This will include a science case and a description of the technology to be used (which should generally be in a mature state). In principal you can make an unsolicited proposal but in practice space agencies have proposal rounds in the same way that individual missions have observing proposal rounds. NASA : Small Explorer (SMEX) and Medium Explorer (MIDEX): every ~2 years alternating Small and Medium, three selected for study for one year from which one is selected for launch. RXTE, GALEX, NuSTAR, Swift, IXPE Arcus, a high resolution X-ray spectroscopy mission was a finalist in the latest MIDEX round but was not selected. Missions of Opportunity (MO): every ~2 years includes balloon programs, ISS instruments and contributions to foreign missions. Suzaku, Hitomi, NICER, XRISM Large missions such as HST, Chandra, JWST are not selected by such proposals but are decided as national priorities through the Astronomy Decadal process. Every ten years a survey is run by the National Academy of Sciences to decide on priorities for both land-based and space-based astronomy. 1960: HST; 1970: VLA; 1980: VLBA; 1990: Chandra and SIRTF; 2000: JWST and ALMA; 2010 WFIRST and LSST.
    [Show full text]
  • ROSAT All-Sky Survey
    ROSAT All-Sky Survey S. R. Kulkarni July 22, 2020{July 27, 2020 The Russian-German mission, Spektr-R¨ongtenGamma (SRG) is on the verge of revolution- izing X-ray astronomy. One of the instruments, eROSITA, will be undertaking an imaging survey of the X-ray sky. Each six-month the entire sky will be covered to a sensitivity which is ten times better than the previous such survey (ROSAT). After eight semesters SRG will undertake pointed observations. I provide a condensed history so that a young student can appreciate the importance of SRG/eROSITA. The first all sky survey was undertaken by the Uhuru (aka SAS-1; 1970) satellite. This was followed up by HEAO-1 (aka HEAO-A; 1977) surveys. These surveys detected 339 and 843 sources in the 2{10 keV band. For those interested in arcana, 1 Uhuru count/s is 1:7 × 10−11 erg cm−2 s−1 in the 2{6 keV band. The next major mission was HEAO-2 (aka Einstein; launched in 1978). This was a game changer since, unlike the past missions which used essentially collimators or shadow cam- eras, the centerpiece of Einstein was a true imaging telescope. Furthermore the mission carried an amazing complement of imagers and spectrometers in the focal plane. The mission coincided with my graduate school (1978-1983). R¨ontgensatellit (ROSAT) was a German mission to undertake an X-ray imaging survey of the entire sky { the first such survey. Launched in 1990 it lasted for eight years. It carried two Positional Sensitive Proportional Counter (PSPC; 0.1{2.4 keV), a High Resolution Imager (HRI) and the Wide Field Camera (WFC; 60{300 A).˚ The PSPC, with a field-of- view of 2 degrees, was the primary work horse for the X-ray sky survey and was > 100 more sensitive than the pioneering Uhuru and HEAO-A1 surveys.
    [Show full text]
  • Arxiv:2009.09047V1 [Astro-Ph.GA] 18 Sep 2020 Theoretical Review, See Zhang 2018)
    DRAFT VERSION SEPTEMBER 22, 2020 Typeset using LATEX twocolumn style in AASTeX63 A 60 kpc Galactic Wind Cone in NGC 3079 EDMUND J. HODGES-KLUCK,1 MIHOKO YUKITA,1, 2 RYAN TANNER,1, 3 ANDREW F. PTAK,1 JOEL N. BREGMAN,4 AND JIANG-TAO LI4 1Code 662, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA 2Henry A. Rowland Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA 3Universities Space Research Association, 7178 Columbia Gateway Dr, Columbia, MD 21046 4Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA ABSTRACT Galactic winds are associated with intense star formation and AGNs. Depending on their formation mecha- nism and velocity they may remove a significant fraction of gas from their host galaxies, thus suppressing star formation, enriching the intergalactic medium, and shaping the circumgalactic gas. However, the long-term evolution of these winds remains mostly unknown. We report the detection of a wind from NGC 3079 to at least 60 kpc from the galaxy. We detect the wind in FUV line emission to 60 kpc (as inferred from the broad FUV filter in GALEX) and in X-rays to at least 30 kpc. The morphology, luminosities, temperatures, and densities indicate that the emission comes from shocked material, and the O/Fe ratio implies that the X-ray emitting gas is enriched by Type II supernovae. If so, the speed inferred from simple shock models is about 500 km s−1, which is sufficient to escape the galaxy. However, the inferred kinetic energy in the wind from visible components is substantially smaller than canonical hot superwind models.
    [Show full text]
  • GALEX: Galaxy Evolution Explorer
    GALEX: Galaxy Evolution Explorer Barry F. Madore Carnegie Observatories, Pasadena CA 91101 Abstract. We review recent scientific results from the Galaxy Evolution Explorer with special emphasis on star formation in nearby resolved galaxies. INTRODUCTION The Satellite The Galaxy Evolution Explorer (GALEX) is a NASA Small Explorer class mission. It consists of a 50 cm-diameter, modified Ritchey-Chrétien telescope with four operating modes: Far-UV (FUV) and Near-UV (NUV) imaging, and FUV and NUV spectroscopy. Æ The telescope has a 3-m focal length and has Al-MgF2 coatings. The field of view is 1.2 circular. An optics wheel can position a CaF2 imaging window, a CaF2 transmission grism, or a fully opaque mask in the beam. Spectroscopic observations are obtained at multiple grism-sky dispersion angles, so as to mitigate spectral overlap effects. The FUV (1528Å: 1344-1786Å) and NUV (2271Å: 1771-2831Å) imagers can be operated one at a time or simultaneously using a dichroic beam splitter. The detector system encorporates sealed-tube microchannel-plate detectors. The FUV detector is preceded by a blue-edge filter that blocks the night-side airglow lines of OI1304, 1356, and Lyα. The NUV detector is preceded by a red blocking filter/fold mirror, which produces a sharper long-wavelength cutoff than the detector CsTe photocathode and thereby reduces both zodiacal light background and optical contamination. The peak quantum efficiency of the detector is 12% (FUV) and 8% (NUV). The detectors are linear up to a local (stellar) count-rate of 100 (FUV), 400 (NUV) cps, which corresponds to mAB 14 15.
    [Show full text]
  • Observatories in Space Catherine Turon
    Observatories in Space Catherine Turon To cite this version: Catherine Turon. Observatories in Space. 2010. hal-00569092v1 HAL Id: hal-00569092 https://hal.archives-ouvertes.fr/hal-00569092v1 Submitted on 24 Feb 2011 (v1), last revised 16 Mar 2011 (v2) HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. OBSERVATORIES IN SPACE Catherine Turon GEPI-UMR CNRS 8111, Observatoire de Paris, Section de Meudon, 92195 Meudon, France Keywords: Astronomy, astrophysics, space, observations, stars, galaxies, interstellar medium, cosmic background. Contents 1. Introduction 2. The impact of the Earth atmosphere on astronomical observations 3. High-energy space observatories 4. Optical-Ultraviolet space observatories 5. Infrared, sub-millimeter and millimeter-space observatories 6. Gravitational waves space observatories 7. Conclusion Summary Space observatories are having major impacts on our knowledge of the Universe, from the Solar neighborhood to the cosmological background, opening many new windows out of reach to ground- based observatories. Celestial objects emit all over the electromagnetic spectrum, and the Earth’s atmosphere blocks a large part of them. Moreover, space offers a very stable environment from where the whole sky can be observed with no (or very little) perturbations, providing new observing possibilities.
    [Show full text]
  • SCIENTIFIC PROGRAM 27Th October 2020 TITLE TIME PERSON INSTITUTION AUTHORS (Click to Download Pdf) 15:00 Prof
    SCIENTIFIC PROGRAM 27th October 2020 TITLE TIME PERSON INSTITUTION AUTHORS (click to download pdf) 15:00 Prof. Ana I Universidad WELCOME Gómez de Castro Complutense de Madrid, Spain 15:10 Dr. Julia Space Telescope The ULLYSES Director’s Discretionary Julia Roman-Duval, Roman-Duval Science Institute, USA Program: Charting Young Stars’ Charles Proffitt, Ultraviolet Light with Hubble TalaWanda Monroe, Jo Taylor, and the ULLYSES implementation team at STScI 15:25 Prof. Catherine Boston University, USA Outflows and Disks around Young Catherine Espaillat and Espaillat Stars: Synergies for the Exploration of Gregory Herczeg Ullyses Spectra (ODYSSEUS) 15:40 Mr. Leonardo University of Geneva, The high-energy environment and Leonardo A. dos Santos, dos Santos Switzerland atmospheric escape of small David Ehrenreich, Vincent exoplanets Bourrier 15:55 Ms. Ziyan Kavli Institute of Probing Protoplanetary Disk Winds Ziyan Xu Xu Astronomy and with FUV Absorption Lines Astrophysics – Peking University, China 16:10 Prof. Kevin France University of Colorado, Atmospheric Escape from Extrasolar Kevin France USA Planets: From stellar inputs to exoplanetary signatures with the ESCAPE and CUTE missions 16:25 Prof. Evgenya Arizona State UV-SCOPE: A MidEx Mission Concept Evgenya Shkolnik (ASU), Shkolnik University, USA for the Ultraviolet Spectroscopic David Ardila (JPL), Travis Characterization Of Planets and their Barman (UA), Courtney Environment Dressing (UCB), Mike Line (ASU), et al. 16:40 Prof. Ana I. Universidad Ultraviolet Researcher for the Ana I Gómez de Castro, Gomez de Castro Complutense de Investigation of the Emergence of Life Francesca Bacciotti, Leire Madrid, Spain Beitia-Antero, Ignacio Bustamante, Ada Canet, et al 16:55 Dr. Pol ESA – European Feasibility study for the Pol Ribes-Pleguezuelo, Ribes Pleguezuelo Space Agency, Spain implementation of small-size Fanny Keller, Matteo astronomical UV telescopes Taccola 17:10 UVA Working UV Photometry Group Doc.
    [Show full text]
  • Nasa Advisory Council Astrophysics Subcommittee
    NAC Astrophysics Subcommittee Meeting July 2-3, 2008 NASA ADVISORY COUNCIL ASTROPHYSICS SUBCOMMITTEE July 2-3, 2008 NASA Headquarters Washington D.C. MEETING REPORT _____________________________________________________________ Craig Hogan, Chair _____________________________________________________________ for Hashima Hasan, Executive Secretary 1 NAC Astrophysics Subcommittee Meeting July 2-3, 2008 Table of Contents Introduction and Announcements …………………………………………..3 Astrophysics Division Update…………………………………………………..3 Decadal Survey Update………………………………………………………..….7 Senior Review………………………………………………………………………….7 GLAST Update………………………………………………………………………….8 HST SM4 Update………………………………………………………………………8 GPRA discussion…………………………………………………………………….10 Discussion, general…………………………………………………………………11 Exoplanet Task Force presentation…………………………………………12 AAAC Exoplanet TF discussion………………………………………………..13 Discussion, general…………………………………………………………………14 Wrap-up, Recommendations, Actions…………………………………..14 Appendix A- Attendees Appendix B- Agenda Appendix C- Membership list 2 NAC Astrophysics Subcommittee Meeting July 2-3, 2008 Introduction and Announcements Chairman of the Astrophysics Subcommittee (APS) Craig Hogan opened the meeting, and Andrew Lange joined by phone. Dr. Hogan briefly reviewed meeting processes, and reminded APS of its role as advising the NASA Advisory Council (NAC), restricting the committee to advising on Astrophysics (AP) science at NASA. Committee members introduced themselves. Ethics Briefing David Barrett gave an ethics briefing, explaining
    [Show full text]
  • Unveiling the Afterlife of Galaxies with Ultraviolet Data
    Galaxy Evolution and Feedback across Different Environments Proceedings IAU Symposium No. 359, 2020 T. Storchi-Bergmann, W. Forman, R. Overzier & R. Riffel, eds. doi:10.1017/S1743921320001611 Unveiling the afterlife of galaxies with ultraviolet data Ariel Werle1,2 1INAF - Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy 2Instituto de Astronomia, Geof´ısica e Ciˆencias Atmosf´ericas, Universidade de S˜ao Paulo, R. do Mat˜ao 1226, 05508-090 S˜ao Paulo, Brazil email: [email protected] Abstract. Recent works have shown that early-type galaxies (ETGs) are much more complex than early studies suggested. We present early results from a combined analysis of optical spectra and ultraviolet photometry for a sample of 3453 red sequence galaxies in at z<0.1 that are classified as elliptical by Galaxy Zoo. By measuring the Gini index of the star-formation histories derived by starlight, we investigate the complexity of the mixture of stellar populations required to describe ETGs in our sample. When fitting only optical spectra, starlight assigns more or less the same mixture of stellar populations to all ETGs, while the addition of UV data unveils a bimodallity in the star-formation histories of these galaxies. We find evidence for stellar populations younger than 1 Gyr in 17 per cent of our sample, indicating that some galaxies do not stay permanently quenched after reaching the red sequence. Keywords. galaxies: evolution, galaxies: elliptical and lenticular, cD, ultraviolet: galaxies 1. Introduction Studies of the stellar populations of early-type galaxies (ETGs) based on their optical stellar continuum are unable to capture some nuances in their star-formation histories.
    [Show full text]
  • Lessons Learned
    A GALEX Instrument Overview and Lessons Learned Patrick Morrissey California Institute of Technology, MS405-47, 1200 E. California Blvd., Pasadena, CA, USA ABSTRACT GALEX is a NASA Small Explorer mission that was launched in April 2003 and is now performing a survey of the sky in the far and near ultraviolet (FUV and NUV, 155 nm and 220 nm, respectively). The instrument comprises a 50 cm Ritchey-Chr´etien telescope with selectable imaging window or objective grism feeding a pair of photon-counting, microchannel-plate, delay-line readout detectors through a multilayer dichroic beamsplitter. The baseline mission is approximately 50% complete, with the instrument meeting its performance requirements for astrometry, photometry and resolution. Operating GALEX with a very small team has been a challenge, yet we have managed to resolve numerous satellite anomalies without loss of performance (only efficiency). Many of the most significant operations issues of our successful on-going mission will be reported here along with lessons for future projects. Keywords: Ultraviolet, Detector, Microchannel plate, GALEX, Lessons learned 1. INTRODUCTION The Galaxy Evolution Explorer (GALEX) is a NASA Small Explorer mission∗ currently performing an all-sky ultraviolet survey in two bands.1 GALEX was launched on an Orbital Sciences Corporation (Dulles, VA) Pegasus rocket on 28 April 2003 at 12:00 UT from the Kennedy Space Center into a circular, 700 km, 29◦ inclination orbit. While small in size, the instrument is designed to image a very wide 1.25◦ field of view with 400 − 600 resolution and sensitivity down to mAB ∼ 25 in the deepest modes. This is achieved with a pair of photon-counting, micro- channel plate (MCP), delay-line readout detectors differing mainly in choice of cathode material (CsI and Cs2Te).
    [Show full text]
  • Observatories in Space
    OBSERVATORIES IN SPACE Catherine Turon GEPI-UMR CNRS 8111, Observatoire de Paris, Section de Meudon, 92195 Meudon, France Keywords: Astronomy, astrophysics, space, observations, stars, galaxies, interstellar medium, cosmic background. Contents 1. Introduction 2. The impact of the Earth atmosphere on astronomical observations 3. High-energy space observatories 4. Optical-Ultraviolet space observatories 5. Infrared, sub-millimeter and millimeter-space observatories 6. Gravitational waves space observatories 7. Conclusion Summary Space observatories are having major impacts on our knowledge of the Universe, from the Solar neighborhood to the cosmological background, opening many new windows out of reach to ground-based observatories. Celestial objects emit all over the electromagnetic spectrum, and the Earth’s atmosphere blocks a large part of them. Moreover, space offers a very stable environment from where the whole sky can be observed with no (or very little) perturbations, providing new observing possibilities. This chapter presents a few striking examples of astrophysics space observatories and of major results spanning from the Solar neighborhood and our Galaxy to external galaxies, quasars and the cosmological background. 1. Introduction Observing the sky, charting the places, motions and luminosities of celestial objects, elaborating complex models to interpret their apparent positions and their variations, and figure out the position of the Earth – later the Solar System or the Galaxy – in the Universe is a long-standing activity of mankind. It has been made for centuries from the ground and in the optical wavelengths, first measuring the positions, motions and brightness of stars, then analyzing their color and spectra to understand their physical nature, then analyzing the light received from other objects: gas, nebulae, quasars, etc.
    [Show full text]