Probing the Local Bubble with Diffuse Interstellar Bands I
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Upon Reconstructing the Origin of the Local Bubble and Loop I Via Radioisotopic Signatures on Earth
galaxies Conference Report A Way Out of the Bubble Trouble?—Upon Reconstructing the Origin of the Local Bubble and Loop I via Radioisotopic Signatures on Earth Michael Mathias Schulreich 1,* ID , Dieter Breitschwerdt 1, Jenny Feige 1 and Christian Dettbarn 2 1 Zentrum für Astronomie und Astrophysik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany; [email protected] (D.B.); [email protected] (J.F.) 2 Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstraße 12–14, 69120 Heidelberg, Germany; [email protected] * Correspondence: [email protected] Received: 31 January 2018; Accepted: 22 February 2018; Published: 25 February 2018 Abstract: Deep-sea archives all over the world show an enhanced concentration of the radionuclide 60Fe, isolated in layers dating from about 2.2 Myr ago. Since this comparatively long-lived isotope is not naturally produced on Earth, such an enhancement can only be attributed to extraterrestrial sources, particularly one or several nearby supernovae in the recent past. It has been speculated that these supernovae might have been involved in the formation of the Local Superbubble, our Galactic habitat. Here, we summarize our efforts in giving a quantitative evidence for this scenario. Besides analytical calculations, we present results from high-resolution hydrodynamical simulations of the Local Superbubble and its presumptive neighbor Loop I in different environments, including a self-consistently evolved supernova-driven interstellar medium. For the superbubble modeling, the time sequence and locations of the generating core-collapse supernova explosions are taken into account, which are derived from the mass spectrum of the perished members of certain, carefully preselected stellar moving groups. -
Science Fiction Stories with Good Astronomy & Physics
Science Fiction Stories with Good Astronomy & Physics: A Topical Index Compiled by Andrew Fraknoi (U. of San Francisco, Fromm Institute) Version 7 (2019) © copyright 2019 by Andrew Fraknoi. All rights reserved. Permission to use for any non-profit educational purpose, such as distribution in a classroom, is hereby granted. For any other use, please contact the author. (e-mail: fraknoi {at} fhda {dot} edu) This is a selective list of some short stories and novels that use reasonably accurate science and can be used for teaching or reinforcing astronomy or physics concepts. The titles of short stories are given in quotation marks; only short stories that have been published in book form or are available free on the Web are included. While one book source is given for each short story, note that some of the stories can be found in other collections as well. (See the Internet Speculative Fiction Database, cited at the end, for an easy way to find all the places a particular story has been published.) The author welcomes suggestions for additions to this list, especially if your favorite story with good science is left out. Gregory Benford Octavia Butler Geoff Landis J. Craig Wheeler TOPICS COVERED: Anti-matter Light & Radiation Solar System Archaeoastronomy Mars Space Flight Asteroids Mercury Space Travel Astronomers Meteorites Star Clusters Black Holes Moon Stars Comets Neptune Sun Cosmology Neutrinos Supernovae Dark Matter Neutron Stars Telescopes Exoplanets Physics, Particle Thermodynamics Galaxies Pluto Time Galaxy, The Quantum Mechanics Uranus Gravitational Lenses Quasars Venus Impacts Relativity, Special Interstellar Matter Saturn (and its Moons) Story Collections Jupiter (and its Moons) Science (in general) Life Elsewhere SETI Useful Websites 1 Anti-matter Davies, Paul Fireball. -
Solar System
Solar System From Wikipedia, the free encyclopedia This article is about the Sun and its planetary system. For other systems, see planetary system and star system. Solar System The Sun and planets of the Solar System. Sizes are to scale, distances and illumination are not. Age 4.568 billion years Location Local Interstellar Cloud, Local Bubble, Orion–Cygnus Arm, Milky Way System mass 1.0014 solar masses Nearest star Proxima Centauri (4.22 ly), Alpha Centauri system (4.37 ly) Nearest Alpha Centauri system (4.37 ly) knownplanetary system Planetary system Semi-major axis 30.10 AU (4.503 billion km) of outer planet (Neptune) Distance 50 AU to Kuiper cliff No. of stars 1 Sun No. of planets 8 Mercury, Venus, Earth, Mars,Jupiter, Saturn, Uranus, Neptune No. of Possibly several hundred.[1] known dwarf 5 (Ceres, Pluto, Haumea,Makemake, Eris) are currently planets recognized by the IAU No. of 422 (173 of planets[2] and 249 of minor planets[3]) known natural satellites No. of 628,057 (as of 2013-12-12)[4] known minor planets No. of 3,244 (as of 2013-12-12)[4] known comets No. of 19 identified round satellites Orbit about the Galactic Center Inclination 60.19° (ecliptic) ofinvariable plane to thegalactic plane Distance to 27,000±1,000 ly Galactic Center Orbital speed 220 km/s Orbital period 225–250 Myr Star-related properties Spectral type G2V [5] Frost line ≈5 AU Distance ≈120 AU toheliopause Hill ≈1–2 ly sphere radius The Solar System[a] is the Sun and the objects that orbit the Sun. -
Solar Wind Charge Exchange Contributions to the Diffuse X-Ray Emission
Solar Wind Charge Exchange Contributions to the Diffuse X-Ray Emission T. E. Cravensa, I. P. Robertsona, S. Snowdenb, K. Kuntzc, M. Collierb and M. Medvedeva aDept. of Physics and Astronomy, Malott Hall, 1251 Wescoe Hall Dr., University of Kansas, Lawrence, KS 66045 USA bNASA Goddard Space Flight Center, Greenbelt, MD, 20771 USA cDept. of Physics and Astronomy, Johns Hopkins University, 366 Bloomberg Center, 3400 N. Charles St., Baltimore, MD 21218 USA Abstract: Astrophysical x-ray emission is typically associated with hot collisional plasmas, such as the million degree gas residing in the solar corona or in supernova remnants. However, x-rays can also be produced in cooler gas by charge exchange collisions between highly-charged ions and neutral atoms or molecules. This mechanism produces soft x-ray emission plasma when the solar wind interacts with neutral gas in the solar system. Examples of such x-ray sources include comets, the terrestrial magnetosheath, and the heliosphere (where the solar wind interacts with incoming interstellar neutral gas). Heliospheric emission is thought to make a significant contribution to the observed soft x-ray background (SXRB). This emission needs to be better understood so that it can be distinguished from the SXRB emission associated with hot interstellar gas and the galactic halo. Keywords: x-rays, charge exchange, local bubble, heliosphere, solar wind PACS: 95.85 Nv; 96.60 Vg; 96.50 Ci; 96.50 Zc INTRODUCTION A key diagnostic tool for hot astrophysical plasmas is x-ray emission [e.g., 1]. Hot plasmas produce x-rays collisionally, both in the continuum from free-free and bound- free (e.g., electron-ion recombination) transitions and as line emission from highly ionized species (bound-bound transitions). -
Physical Properties of the Local Interstellar Medium
Space Sci Rev (2009) 143: 323–331 DOI 10.1007/s11214-008-9422-4 Physical Properties of the Local Interstellar Medium Seth Redfield Received: 3 April 2008 / Accepted: 23 July 2008 / Published online: 12 September 2008 © Springer Science+Business Media B.V. 2008 Abstract The observed properties of the local interstellar medium (LISM) have been facil- itated by a growing ultraviolet and optical database of high spectral resolution observations of interstellar absorption toward nearby stars. Such observations provide insight into the physical properties (e.g., temperature, turbulent velocity, and depletion onto dust grains) of the population of warm clouds (e.g., 7000 K) that reside within the Local Bubble. In particu- lar, I will focus on the dynamical properties of clouds within ∼15 pc of the Sun. This simple dynamical model addresses a wide range of issues, including, the location of the Sun as it pertains to the relationship between local interstellar clouds and the circumheliospheric in- terstellar medium (CHISM), the creation of small cold clouds inside the Local Bubble, and the association of interacting warm clouds and small-scale density fluctuations that cause interstellar scintillation. Local interstellar clouds that can be easily distinguished based on their dynamical properties also differentiate themselves by other physical properties. For example, the two nearest local clouds, the Local Interstellar Cloud (LIC) and the Galactic (G) Cloud, show distinct properties in temperature and depletion of iron and magnesium. The availability of large-scale observational surveys allows for studies of the global charac- teristics of our local interstellar environment, which will ultimately be necessary to address fundamental questions regarding the origins and evolution of the local interstellar medium. -
Interstellar Heliospheric Probe/Heliospheric Boundary Explorer Mission—A Mission to the Outermost Boundaries of the Solar System
Exp Astron (2009) 24:9–46 DOI 10.1007/s10686-008-9134-5 ORIGINAL ARTICLE Interstellar heliospheric probe/heliospheric boundary explorer mission—a mission to the outermost boundaries of the solar system Robert F. Wimmer-Schweingruber · Ralph McNutt · Nathan A. Schwadron · Priscilla C. Frisch · Mike Gruntman · Peter Wurz · Eino Valtonen · The IHP/HEX Team Received: 29 November 2007 / Accepted: 11 December 2008 / Published online: 10 March 2009 © Springer Science + Business Media B.V. 2009 Abstract The Sun, driving a supersonic solar wind, cuts out of the local interstellar medium a giant plasma bubble, the heliosphere. ESA, jointly with NASA, has had an important role in the development of our current under- standing of the Suns immediate neighborhood. Ulysses is the only spacecraft exploring the third, out-of-ecliptic dimension, while SOHO has allowed us to better understand the influence of the Sun and to image the glow of The IHP/HEX Team. See list at end of paper. R. F. Wimmer-Schweingruber (B) Institute for Experimental and Applied Physics, Christian-Albrechts-Universität zu Kiel, Leibnizstr. 11, 24098 Kiel, Germany e-mail: [email protected] R. McNutt Applied Physics Laboratory, John’s Hopkins University, Laurel, MD, USA N. A. Schwadron Department of Astronomy, Boston University, Boston, MA, USA P. C. Frisch University of Chicago, Chicago, USA M. Gruntman University of Southern California, Los Angeles, USA P. Wurz Physikalisches Institut, University of Bern, Bern, Switzerland E. Valtonen University of Turku, Turku, Finland 10 Exp Astron (2009) 24:9–46 interstellar matter in the heliosphere. Voyager 1 has recently encountered the innermost boundary of this plasma bubble, the termination shock, and is returning exciting yet puzzling data of this remote region. -