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The Scale-Invariant Vacuum (SIV) Theory: a Possible Origin of Dark Matter and Dark Energy
universe Article The Scale-Invariant Vacuum (SIV) Theory: A Possible Origin of Dark Matter and Dark Energy Andre Maeder 1,* and Vesselin G. Gueorguiev 2,3 1 Geneva Observatory, University of Geneva, chemin des Maillettes 51, CH-1290 Sauverny, Switzerland 2 Institute for Advanced Physical Studies, Montevideo Street, Sofia 1618, Bulgaria; [email protected] 3 Ronin Institute for Independent Scholarship, 127 Haddon Pl., Montclair, NJ 07043, USA * Correspondence: [email protected] Received: 7 February 2020; Accepted: 9 March 2020; Published: 18 March 2020 Abstract: The Scale Invariant Vacuum (SIV) theory rests on the basic hypothesis that the macroscopic empty space is scale invariant. This hypothesis is applied in the context of the Integrable Weyl Geometry, where it leads to considerable simplifications in the scale covariant cosmological equations. After an initial explosion and a phase of braking, the cosmological models show a continuous acceleration of the expansion. Several observational tests of the SIV cosmology are performed: on the relation between H0 and the age of the Universe, on the m − z diagram for SNIa data and its extension to z = 7 with quasars and GRBs, and on the H(z) vs. z relation. All comparisons show a very good agreement between SIV predictions and observations. Predictions for the future observations of the redshift drifts are also given. In the weak field approximation, the equation of motion contains, in addition to the classical Newtonian term, an acceleration term (usually very small) depending on the velocity. The two-body problem is studied, showing a slow expansion of the classical conics. The new equation has been applied to clusters of galaxies, to rotating galaxies (some proximities with Modifies Newtonian Dynamics, MOND, are noticed), to the velocity dispersion vs. -
XIII Publications, Presentations
XIII Publications, Presentations 1. Refereed Publications E., Kawamura, A., Nguyen Luong, Q., Sanhueza, P., Kurono, Y.: 2015, The 2014 ALMA Long Baseline Campaign: First Results from Aasi, J., et al. including Fujimoto, M.-K., Hayama, K., Kawamura, High Angular Resolution Observations toward the HL Tau Region, S., Mori, T., Nishida, E., Nishizawa, A.: 2015, Characterization of ApJ, 808, L3. the LIGO detectors during their sixth science run, Classical Quantum ALMA Partnership, et al. including Asaki, Y., Hirota, A., Nakanishi, Gravity, 32, 115012. K., Espada, D., Kameno, S., Sawada, T., Takahashi, S., Ao, Y., Abbott, B. P., et al. including Flaminio, R., LIGO Scientific Hatsukade, B., Matsuda, Y., Iono, D., Kurono, Y.: 2015, The 2014 Collaboration, Virgo Collaboration: 2016, Astrophysical Implications ALMA Long Baseline Campaign: Observations of the Strongly of the Binary Black Hole Merger GW150914, ApJ, 818, L22. Lensed Submillimeter Galaxy HATLAS J090311.6+003906 at z = Abbott, B. P., et al. including Flaminio, R., LIGO Scientific 3.042, ApJ, 808, L4. Collaboration, Virgo Collaboration: 2016, Observation of ALMA Partnership, et al. including Asaki, Y., Hirota, A., Nakanishi, Gravitational Waves from a Binary Black Hole Merger, Phys. Rev. K., Espada, D., Kameno, S., Sawada, T., Takahashi, S., Kurono, Lett., 116, 061102. Y., Tatematsu, K.: 2015, The 2014 ALMA Long Baseline Campaign: Abbott, B. P., et al. including Flaminio, R., LIGO Scientific Observations of Asteroid 3 Juno at 60 Kilometer Resolution, ApJ, Collaboration, Virgo Collaboration: 2016, GW150914: Implications 808, L2. for the Stochastic Gravitational-Wave Background from Binary Black Alonso-Herrero, A., et al. including Imanishi, M.: 2016, A mid-infrared Holes, Phys. -
Heliophysics Community of Practice for Teachers
Heliophysics Community of Practice for Teachers • A multi-mission effort currently led by THEMIS-ARTEMIS Education/Public Outreach (E/PO) and supported by Van Allen Probes and IBEX, with facilitation from the Heliophysics E/PO Forum. • A nationwide community of middle and high school teachers who work together to design and implement an active, collaborative, supportive network of educators who are interested in teaching Sun-Earth science. • Began one year ago with teachers from Hawaii, Alaska, Puerto Rico, and the Continental US. • Currently growing the community to include a wider network of teachers and empowering the original core instructors to take on greater leadership roles within the community. Structure: • Monthly meetings with a face to face virtual experience, archived for later review • Science lectures- Solar Dynamics Observatory, Van Allen Probes, MAVEN, others ??? • Classroom activity ideas shared by NASA E/PO specialists and teachers • Sharing of ideas about best practices for teaching Heliophysics • Multi-day Online Community Retreat • Community Workspace “Come Out and Play!” …..How You Can Get Involved: • Opportunity to Share Your Science- Teachers have said that hearing directly from scientists is one of the most valuable aspects of their experience in the Community of Practice. • Tell others- Let the NASA community know about the success of this program, we are excited about our growth and success and hope funding support will continue. • Ideas for including students in authentic research experiences using your data? Let us know! • Other ideas? . -
The Van Allen Probes' Contribution to the Space Weather System
L. J. Zanetti et al. The Van Allen Probes’ Contribution to the Space Weather System Lawrence J. Zanetti, Ramona L. Kessel, Barry H. Mauk, Aleksandr Y. Ukhorskiy, Nicola J. Fox, Robin J. Barnes, Michele Weiss, Thomas S. Sotirelis, and NourEddine Raouafi ABSTRACT The Van Allen Probes mission, formerly the Radiation Belt Storm Probes mission, was renamed soon after launch to honor the late James Van Allen, who discovered Earth’s radiation belts at the beginning of the space age. While most of the science data are telemetered to the ground using a store-and-then-dump schedule, some of the space weather data are broadcast continu- ously when the Probes are not sending down the science data (approximately 90% of the time). This space weather data set is captured by contributed ground stations around the world (pres- ently Korea Astronomy and Space Science Institute and the Institute of Atmospheric Physics, Czech Republic), automatically sent to the ground facility at the Johns Hopkins University Applied Phys- ics Laboratory, converted to scientific units, and published online in the form of digital data and plots—all within less than 15 minutes from the time that the data are accumulated onboard the Probes. The real-time Van Allen Probes space weather information is publicly accessible via the Van Allen Probes Gateway web interface. INTRODUCTION The overarching goal of the study of space weather ing radiation, were the impetus for implementing a space is to understand and address the issues caused by solar weather broadcast capability on NASA’s Van Allen disturbances and the effects of those issues on humans Probes’ twin pair of satellites, which were launched in and technological systems. -
Hubble Finds Birth Certificate of Oldest Known Star 7 March 2013
Hubble finds birth certificate of oldest known star 7 March 2013 But earlier estimates from observations dating back to 2000 placed the star as old as 16 billion years. And this age range presented a potential dilemma for cosmologists. "Maybe the cosmology is wrong, stellar physics is wrong, or the star's distance is wrong," Bond said. "So we set out to refine the distance." The new Hubble age estimates reduce the range of measurement uncertainty, so that the star's age overlaps with the universe's age—as independently determined by the rate of expansion of space, an analysis of the microwave background from the big bang, and measurements of radioactive decay. This "Methuselah star," cataloged as HD 140283, has been known about for more than a century because of its fast motion across the sky. The high This is a Digitized Sky Survey image of the oldest star rate of motion is evidence that the star is simply a with a well-determined age in our galaxy. The aging star, cataloged as HD 140283, lies 190.1 light-years away. visitor to our stellar neighborhood. Its orbit carries it The Anglo-Australian Observatory UK Schmidt telescope down through the plane of our galaxy from the photographed the star in blue light. Credit: Digitized Sky ancient halo of stars that encircle the Milky Way, Survey (DSS), STScI/AURA, Palomar/Caltech, and and will eventually slingshot back to the galactic UKSTU/AAO halo. (Phys.org) —A team of astronomers using NASA's Hubble Space Telescope has taken an important step closer to finding the birth certificate of a star that's been around for a very long time. -
Missions Spatiales NASA Et
Missions spatiales NASA et ESA NASA : Système solaire-1 ● Astéroides – Asteroid Redirect Initiative – Dawn – Near Earth Asteroid Rendezvous (NEAR) – Osiris-REX ● Comètes – Deep Impact – EPOXI – Rosetta – Stardust-NExT NASA : Système solaire-2 ● Jupiter ● Saturne – Europa Mission – Cassini – Galileo – Pioneer – Juno – Voyager – Pioneer – Voyager NASA : Système solaire-3 ● Mercure ● Uranus et Neptune – MESSENGER Voyager ● Vénus ● Pluton – Magellan – New Horizons – Pioneer NASA : Système solaire-4 ● Lune – Apollo – Clementine – GRAIL – LADEE – LCROSS – LRO (Lunar Reconnaissance Orbiter) – Mini-RF – Moon Mineralogy Mapper – Ranger – Surveyor NASA : Système solaire-5 ● Soleil et son Influence sur la ● SDO Terre ● SOHO ● Solar Anomalous and Magnetospherice ● Explorer Particle Explorer (SAMPEX) ● FAST ● Solar Orbiter Collaboration ● Geotail ● Solar Probe Plus ● Hinode (Solar-b) ● Sounding Rockets ● Ionospheric Connection Explorer (ICON) ● STEREO ● IMAGE ● THEMIS ● IRIS: Interface Region Imaging Spectrograph ● TIMED ● Magnetospheric MultiScale (MMS) ● TRACE ● Polar ● Ulysses ● RHESSI ● Van Allen Probes NASA : Système solaire-6 Mars ● InSight ● Mars Exploration Rover ● Mars Global Surveyor ● Mars Odyssey ● Mars Pathfinder ● Mars Reconnaissance Orbiter ● Mars Science Laboratory, Curiosity ● MAVEN ● Phoenix ● Viking Missions NASA Mars Missions Univers-1 ● ● Big Bang and Cosmology Black Holes – Chandra – ASTRO-1 – Fermi Gamma-ray Space Telescope – ASTRO-2 – GLAST – Chandra – Herschel – Compton Gamma-Ray Observatory – NuSTAR – Cosmic Background Explorer -
Gtosat: a Pathfinder for a Smallsat-Based Operational Space Weather Program (And We Do Science!)
GTOSat: A Pathfinder for a Smallsat-Based Operational Space Weather Program (And we do science!) Larry Kepko1, Lauren Blum1, Drew Turner2 and Alison Jaynes3 1NASA GSFC, 2The Aerospace Corporation, 3University of Iowa Strong desire & need for a space weather program 2012 Decadal Survey for Heliophysics recommended a space weather program “A vision for space weather and climatology” at $100-200M / year That program has not materialized Small satellites (<ESPA) have potential to achieve that goal RBSP / Van Allen Probes Revolutionized our understanding of Earth’s radiation belts, but 2 issues: 1. Limited radial distance - missed outer zone dynamics beyond L~5.5 2. It’s run out of fuel (decommission <early 2020) GTOSat is ready to fill those gaps Acceleration locations were sometimes beyond RBSP’s apogee μ = 735–765 MeV/G Boyd et al. (2018) Schiller et al (2013) Geosynchronous Transfer Orbit Satellite (GTOSat) Robust, low-cost cubesat with flight proven instruments for space weather and high quality science • Selected in H-TIDeS 2018 - 6U CubeSat, $4.35M total budget (including 1-year ops) - Designed to study the dynamics of outer belt electrons (science goal) - Explicitly a SmallSat space weather & constellation pathfinder - Confirmed CSLI selectee, working launch to GTO in early 2021 - Working with both JSC and KSC/LSP on de-orbit options - current baseline is passive - SRR 10/31/18, CDR 7/18/19, PSR 10/21/20 Carrying 2 instruments (MagEIS & Mag) that are on Van Allen Probes Leverages GSFC Dellingr experience (16 months and counting), combined with internal investments in C&DH and in-house SmallSat capability, and commercial solutions. -
Van Allen Probe Daily Flux Model
EGU2020-12084 An Empirical Model of Electron Flux from the Seven-Year Van Allen Probe Mission Christine Gabrielse1, J. Lee1, J. Roeder1, S. Claudepierre1, A. Runov2, T. Paul O’Brien1, D. L. Turner1,3, J. Fennell1, J. B. Blake1, Y. Miyoshi4, K. Keika5, N. Higashio6, I. Shinohara7, S. Kurita4, S. Imajo4 1The Aerospace Corporation 2Earth, Planetary, and Space Sciences Dept, UCLA 3Now at John Hopkins Applied Physic Laboratory 4Institute for Space-Earth Environmental Research, Nagoya University 5Graduate School of Science, The University of Tokyo 6Research & Development Directorate, Japan Aerospace Exploration Agency 7Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency May 4, 2020 None of the Figures in this presentation may be copied or used. All Rights Reserved. © 2020 The Aerospace Corporation 1 (Unless they were published elsewhere, e.g. slide 2, and copyright belongs to someone else). Background and Motivation Desire data-based model on day-long timescales • Empirical models have been designed to predict radiation environment (e.g., Roeder et al., Space Weather 2005; Chen et al., JGR, 2014), but they may not capture actual fluxes observed a particular day • AE9 provides probability of occurrence (percentile levels) for flux and fluence averaged over different exposure periods—not meant to capture daily variations • Effects that require shorter-term integrals of the outer radiation belt may need special attention when it comes to environmental assessments. – Spacecraft charging (DeForest, 1972; Olsen, 1983; Koons et al., 2006; Fennell et al., 2008) • Practical example: GPS solar array current and voltage degrades faster than predicted by any model (e.g., Messenger et al., 2011)—Are we correctly modeling the radiation environment? Figure: Black line is remaining factor of solar array current. -
Heliophysicist Waits Nearly 10 Years for Pluto Flyby 8 July 2015, by Lori Keesey
Heliophysicist waits nearly 10 years for Pluto flyby 8 July 2015, by Lori Keesey heliophysicist Nikolaos Paschalidis will be one happy man: he created a mission-enabling technology that will help uncover details about the atmosphere of the never-before-visited dwarf planet. "We have been waiting for this for a long time," said the Greek native, who now works as a scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "That's what happens when it takes more than nine years to get to your destination." When employed by the Maryland-based Johns Hopkins Applied Physics Laboratory (APL), which is operating the New Horizons mission for NASA, Paschalidis designed five application-specific integrated circuits—some now patented—for the mission's Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI), developed by APL Principal Investigator Ralph McNutt. The instrument, one of seven flying on New Horizons, is designed to measure the composition and density of material, such as nitrogen and carbon monoxide, which escapes from Pluto's atmosphere and subsequently is ionized by solar Artist’s concept of the New Horizons spacecraft as it ultraviolet light. The atmospheric chemicals pick up approaches Pluto and its largest moon, Charon, in July energy from the solar wind and stream away from 2015. The craft's miniature cameras, radio science Pluto. experiment, ultraviolet and infrared spectrometers and space plasma experiments will characterize the global Until now, knowledge about the mysterious planet's geology and geomorphology of Pluto and Charon, map atmosphere has come mainly from stellar their surface compositions and temperatures, and occultation, when the planet passes in front of examine Pluto's atmosphere in detail. -
121012-AAS-221 Program-14-ALL, Page 253 @ Preflight
221ST MEETING OF THE AMERICAN ASTRONOMICAL SOCIETY 6-10 January 2013 LONG BEACH, CALIFORNIA Scientific sessions will be held at the: Long Beach Convention Center 300 E. Ocean Blvd. COUNCIL.......................... 2 Long Beach, CA 90802 AAS Paper Sorters EXHIBITORS..................... 4 Aubra Anthony ATTENDEE Alan Boss SERVICES.......................... 9 Blaise Canzian Joanna Corby SCHEDULE.....................12 Rupert Croft Shantanu Desai SATURDAY.....................28 Rick Fienberg Bernhard Fleck SUNDAY..........................30 Erika Grundstrom Nimish P. Hathi MONDAY........................37 Ann Hornschemeier Suzanne H. Jacoby TUESDAY........................98 Bethany Johns Sebastien Lepine WEDNESDAY.............. 158 Katharina Lodders Kevin Marvel THURSDAY.................. 213 Karen Masters Bryan Miller AUTHOR INDEX ........ 245 Nancy Morrison Judit Ries Michael Rutkowski Allyn Smith Joe Tenn Session Numbering Key 100’s Monday 200’s Tuesday 300’s Wednesday 400’s Thursday Sessions are numbered in the Program Book by day and time. Changes after 27 November 2012 are included only in the online program materials. 1 AAS Officers & Councilors Officers Councilors President (2012-2014) (2009-2012) David J. Helfand Quest Univ. Canada Edward F. Guinan Villanova Univ. [email protected] [email protected] PAST President (2012-2013) Patricia Knezek NOAO/WIYN Observatory Debra Elmegreen Vassar College [email protected] [email protected] Robert Mathieu Univ. of Wisconsin Vice President (2009-2015) [email protected] Paula Szkody University of Washington [email protected] (2011-2014) Bruce Balick Univ. of Washington Vice-President (2010-2013) [email protected] Nicholas B. Suntzeff Texas A&M Univ. suntzeff@aas.org Eileen D. Friel Boston Univ. [email protected] Vice President (2011-2014) Edward B. Churchwell Univ. of Wisconsin Angela Speck Univ. of Missouri [email protected] [email protected] Treasurer (2011-2014) (2012-2015) Hervey (Peter) Stockman STScI Nancy S. -
The Space Challenge and Soviet Science Fiction
Corso di Laurea magistrale ( ordinamento ex D.M. 270/2004 ) in Relazioni Internazionali Comparate – International Relations Tesi di Laurea The space challenge and Soviet science fiction Relatore Ch.mo Prof. Duccio Basosi Correlatore Ch.ma Prof. Donatella Possamai Laureanda Serena Zanin Matricola 835564 Anno Accademico 2011 / 2012 TABLE OF CONTENTS ABSTRACT ……………………………………………………………………...1 INTRODUCTION …………………………………………………...…………..7 CHAPTER I The science fiction in the Soviet bloc: the case of Stanislaw Lem’s “Solaris”…………………….…………………………………....…………...…16 CHAPTER II The space race era from the Soviet bloc side …………..….........37 CHAPTER III The enthusiasm for the cosmos and Soviet propaganda ……………….. …………………………...……...………………………………..73 FINAL CONSIDERATIONS ……………...………………………………...101 APPENDIX ........……………………………………………………..……..…106 REFERENCES …..……………………………………………………………113 ACKNOWLEDGEMENTS …………………………………………………..118 ABSTRACT La studiosa Julia Richers sottolinea come le ricerche sulla storia dell’esplorazione spaziale sovietica abbiano tre principali direzioni. La prima riguarda la storia politica della Guerra Fredda che considera la conquista dello spazio e lo sviluppo di potenti missili come parte di una più grande competizione tra gli USA e l’URSS. La seconda esamina in particolar modo lo sviluppo scientifico e tecnologico a partire dagli anni Ottanta, ossia da quando l’abolizione della censura ha permesso l’apertura al pubblico di molti archivi storici e la rivelazione di importanti informazioni. La terza include la propaganda sovietica e la fantascienza come parte fondamentale della storia culturale e sociale sia dell’URSS che della Russia post-rivoluzione. Il presente lavoro analizza la storia dell’esplorazione spaziale sovietica e, partendo dalle sue origini (fine XIX° secolo), prende in considerazione i principali successi che portarono al lancio del primo satellite artificiale nel 1957 e il primo uomo sulla luna nel 1961. -
HIPPARCOS Age-Metallicity Relation of the Solar Neighbourhood Disc Stars
HIPPARCOS age-metallicity relation of the solar neighbourhood disc stars A. Ibukiyama1 and N. Arimoto1;2 1 Institute of Astronomy (IoA), School of Science, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015, Japan 2 National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan Received /Accepted 1 July 2002 Abstract. We derive age-metallicity relations (AMRs) and orbital parameters for the 1658 solar neighbourhood stars to which accurate distances are measured by the HIPPARCOS satellite. The sample stars comprise 1382 thin disc stars, 229 thick disc stars, and 47 halo stars according to their orbital parameters. We find a considerable scatter for thin disc AMR along the one-zone Galactic chemical evolution (GCE) model. Orbits and metallicities of thin disc stars show now clear relation each other. The scatter along the AMR exists even if the stars with the same orbits are selected. We examine simple extension of one-zone GCE models which account for inhomogeneity in the effective yield and inhomogeneous star formation rate in the Galaxy. Both extensions of one-zone GCE model cannot account for the scatter in age - [Fe/H] - [Ca/Fe] relation simultaneously. We conclude, therefore, that the scatter along the thin disc AMR is an essential feature in the formation and evolution of the Galaxy. The AMR for thick disc stars shows that the star formation terminated 8 Gyr ago in thick disc. As already reported by ?)and?), thick disc stars are more Ca-rich than thin disc stars with the same [Fe/H]. We find that thick disc stars show a vertical abundance gradient.