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Modeling Super-Earth Atmospheres in Preparation for Upcoming Extremely Large Telescopes
Modeling Super-Earth Atmospheres In Preparation for Upcoming Extremely Large Telescopes Maggie Thompson1 Jonathan Fortney1, Andy Skemer1, Tyler Robinson2, Theodora Karalidi1, Steph Sallum1 1University of California, Santa Cruz, CA; 2Northern Arizona University, Flagstaff, AZ ExoPAG 19 January 6, 2019 Seattle, Washington Image Credit: NASA Ames/JPL-Caltech/T. Pyle Roadmap Research Goals & Current Atmosphere Modeling Selecting Super-Earths for State of Super-Earth Tool (Past & Present) Follow-Up Observations Detection Preliminary Assessment of Future Observatories for Conclusions & Upcoming Instruments’ Super-Earths Future Work Capabilities for Super-Earths M. Thompson — ExoPAG 19 01/06/19 Research Goals • Extend previous modeling tool to simulate super-Earth planet atmospheres around M, K and G stars • Apply modified code to explore the parameter space of actual and synthetic super-Earths to select most suitable set of confirmed exoplanets for follow-up observations with JWST and next-generation ground-based telescopes • Inform the design of advanced instruments such as the Planetary Systems Imager (PSI), a proposed second-generation instrument for TMT/GMT M. Thompson — ExoPAG 19 01/06/19 Current State of Super-Earth Detections (1) Neptune Mass Range of Interest Earth Data from NASA Exoplanet Archive M. Thompson — ExoPAG 19 01/06/19 Current State of Super-Earth Detections (2) A Approximate Habitable Zone Host Star Spectral Type F G K M Data from NASA Exoplanet Archive M. Thompson — ExoPAG 19 01/06/19 Atmosphere Modeling Tool Evolution of Atmosphere Model • Solar System Planets & Moons ~ 1980’s (e.g., McKay et al. 1989) • Brown Dwarfs ~ 2000’s (e.g., Burrows et al. 2001) • Hot Jupiters & Other Giant Exoplanets ~ 2000’s (e.g., Fortney et al. -
A Wunda-Full World? Carbon Dioxide Ice Deposits on Umbriel and Other Uranian Moons
Icarus 290 (2017) 1–13 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus A Wunda-full world? Carbon dioxide ice deposits on Umbriel and other Uranian moons ∗ Michael M. Sori , Jonathan Bapst, Ali M. Bramson, Shane Byrne, Margaret E. Landis Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA a r t i c l e i n f o a b s t r a c t Article history: Carbon dioxide has been detected on the trailing hemispheres of several Uranian satellites, but the exact Received 22 June 2016 nature and distribution of the molecules remain unknown. One such satellite, Umbriel, has a prominent Revised 28 January 2017 high albedo annulus-shaped feature within the 131-km-diameter impact crater Wunda. We hypothesize Accepted 28 February 2017 that this feature is a solid deposit of CO ice. We combine thermal and ballistic transport modeling to Available online 2 March 2017 2 study the evolution of CO 2 molecules on the surface of Umbriel, a high-obliquity ( ∼98 °) body. Consid- ering processes such as sublimation and Jeans escape, we find that CO 2 ice migrates to low latitudes on geologically short (100s–1000 s of years) timescales. Crater morphology and location create a local cold trap inside Wunda, and the slopes of crater walls and a central peak explain the deposit’s annular shape. The high albedo and thermal inertia of CO 2 ice relative to regolith allows deposits 15-m-thick or greater to be stable over the age of the solar system. -
The Subsurface Habitability of Small, Icy Exomoons J
A&A 636, A50 (2020) Astronomy https://doi.org/10.1051/0004-6361/201937035 & © ESO 2020 Astrophysics The subsurface habitability of small, icy exomoons J. N. K. Y. Tjoa1,?, M. Mueller1,2,3, and F. F. S. van der Tak1,2 1 Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, The Netherlands e-mail: [email protected] 2 SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen, The Netherlands 3 Leiden Observatory, Leiden University, Niels Bohrweg 2, 2300 RA Leiden, The Netherlands Received 1 November 2019 / Accepted 8 March 2020 ABSTRACT Context. Assuming our Solar System as typical, exomoons may outnumber exoplanets. If their habitability fraction is similar, they would thus constitute the largest portion of habitable real estate in the Universe. Icy moons in our Solar System, such as Europa and Enceladus, have already been shown to possess liquid water, a prerequisite for life on Earth. Aims. We intend to investigate under what thermal and orbital circumstances small, icy moons may sustain subsurface oceans and thus be “subsurface habitable”. We pay specific attention to tidal heating, which may keep a moon liquid far beyond the conservative habitable zone. Methods. We made use of a phenomenological approach to tidal heating. We computed the orbit averaged flux from both stellar and planetary (both thermal and reflected stellar) illumination. We then calculated subsurface temperatures depending on illumination and thermal conduction to the surface through the ice shell and an insulating layer of regolith. We adopted a conduction only model, ignoring volcanism and ice shell convection as an outlet for internal heat. -
Space in Central and Eastern Europe
EU 4+ SPACE IN CENTRAL AND EASTERN EUROPE OPPORTUNITIES AND CHALLENGES FOR THE EUROPEAN SPACE ENDEAVOUR Report 5, September 2007 Charlotte Mathieu, ESPI European Space Policy Institute Report 5, September 2007 1 Short Title: ESPI Report 5, September 2007 Editor, Publisher: ESPI European Space Policy Institute A-1030 Vienna, Schwarzenbergplatz 6 Austria http://www.espi.or.at Tel.: +43 1 718 11 18 - 0 Fax - 99 Copyright: ESPI, September 2007 This report was funded, in part, through a contract with the EUROPEAN SPACE AGENCY (ESA). Rights reserved - No part of this report may be reproduced or transmitted in any form or for any purpose without permission from ESPI. Citations and extracts to be published by other means are subject to mentioning “source: ESPI Report 5, September 2007. All rights reserved” and sample transmission to ESPI before publishing. Price: 11,00 EUR Printed by ESA/ESTEC Compilation, Layout and Design: M. A. Jakob/ESPI and Panthera.cc Report 5, September 2007 2 EU 4+ Executive Summary ....................................................................................... 5 Introduction…………………………………………………………………………………………7 Part I - The New EU Member States Introduction................................................................................................... 9 1. What is really at stake for Europe? ....................................................... 10 1.1. The European space community could benefit from a further cooperation with the ECS ................................................................. 10 1.2. However, their economic weight remains small in the European landscape and they still suffer from organisatorial and funding issues .... 11 1.2.1. Economic weight of the ECS in Europe ........................................... 11 1.2.2. Reality of their impact on competition ............................................ 11 1.2.3. Foreign policy issues ................................................................... 12 1.2.4. Internal challenges ..................................................................... 12 1.3. -
The Rings and Inner Moons of Uranus and Neptune: Recent Advances and Open Questions
Workshop on the Study of the Ice Giant Planets (2014) 2031.pdf THE RINGS AND INNER MOONS OF URANUS AND NEPTUNE: RECENT ADVANCES AND OPEN QUESTIONS. Mark R. Showalter1, 1SETI Institute (189 Bernardo Avenue, Mountain View, CA 94043, mshowal- [email protected]! ). The legacy of the Voyager mission still dominates patterns or “modes” seem to require ongoing perturba- our knowledge of the Uranus and Neptune ring-moon tions. It has long been hypothesized that numerous systems. That legacy includes the first clear images of small, unseen ring-moons are responsible, just as the nine narrow, dense Uranian rings and of the ring- Ophelia and Cordelia “shepherd” ring ε. However, arcs of Neptune. Voyager’s cameras also first revealed none of the missing moons were seen by Voyager, sug- eleven small, inner moons at Uranus and six at Nep- gesting that they must be quite small. Furthermore, the tune. The interplay between these rings and moons absence of moons in most of the gaps of Saturn’s rings, continues to raise fundamental dynamical questions; after a decade-long search by Cassini’s cameras, sug- each moon and each ring contributes a piece of the gests that confinement mechanisms other than shep- story of how these systems formed and evolved. herding might be viable. However, the details of these Nevertheless, Earth-based observations have pro- processes are unknown. vided and continue to provide invaluable new insights The outermost µ ring of Uranus shares its orbit into the behavior of these systems. Our most detailed with the tiny moon Mab. Keck and Hubble images knowledge of the rings’ geometry has come from spanning the visual and near-infrared reveal that this Earth-based stellar occultations; one fortuitous stellar ring is distinctly blue, unlike any other ring in the solar alignment revealed the moon Larissa well before Voy- system except one—Saturn’s E ring. -
Arxiv:1009.3071V1 [Astro-Ph.EP] 16 Sep 2010 Eovdfo T Aetsa–R Oiae Yrflce Lig Reflected by Dominated AU– Star–Are 1 Parent About Al Its Than the from Larger Stars
ApJ accepted Exoplanet albedo spectra and colors as a function of planet phase, separation, and metallicity Kerri L. Cahoy, Mark S. Marley NASA Ames Research Center, Moffett Field, CA 94035 [email protected] and Jonathan J. Fortney University of California Santa Cruz, Santa Cruz, CA 95064 ABSTRACT First generation space-based optical coronagraphic telescopes will obtain images of cool gas and ice giant exoplanets around nearby stars. The albedo spectra of exoplan- ets lying at planet-star separations larger than about 1 AU–where an exoplanet can be resolved from its parent star–are dominated by reflected light to beyond 1 µm and are punctuated by molecular absorption features. Here we consider how exoplanet albedo spectra and colors vary as a function of planet-star separation, metallicity, mass, and observed phase for Jupiter and Neptune analogs from 0.35 to 1 µm. We model Jupiter analogs with 1 and 3 the solar abundance of heavy elements, and Neptune analogs × × with 10 and 30 solar abundance of heavy elements. Our model planets orbit a solar × × analog parent star at separations of 0.8 AU, 2 AU, 5 AU, and 10 AU. We use a radiative- convective model to compute temperature-pressure profiles. The giant exoplanets are found to be cloud-free at 0.8 AU, possess H2O clouds at 2 AU, and have both NH3 arXiv:1009.3071v1 [astro-ph.EP] 16 Sep 2010 and H2O clouds at 5 AU and 10 AU. For each model planet we compute moderate resolution (R = λ/∆λ 800) albedo spectra as a function of phase. -
ARIEL – 13Th Appleton Space Conference PLANETS ARE UBIQUITOUS
Background image credit NASA ARIEL – 13th Appleton Space Conference PLANETS ARE UBIQUITOUS OUR GALAXY IS MADE OF GAS, STARS & PLANETS There are at least as many planets as stars Cassan et al, 2012; Batalha et al., 2015; ARIEL – 13th Appleton Space Conference 2 EXOPLANETS TODAY: HUGE DIVERSITY 3700+ PLANETS, 2700 PLANETARY SYSTEMS KNOWN IN OUR GALAXY ARIEL – 13th Appleton Space Conference 3 HUGE DIVERSITY: WHY? FORMATION & EVOLUTION PROCESSES? MIGRATION? INTERACTION WITH STAR? Accretion Gaseous planets form here Interaction with star Planet migration Ices, dust, gas ARIEL – 13th Appleton Space Conference 4 STAR & PLANET FORMATION/EVOLUTION WHAT WE KNOW: CONSTRAINTS FROM OBSERVATIONS – HERSCHEL, ALMA, SOLAR SYSTEM Measured elements in Solar system ? Image credit ESA-Herschel, ALMA (ESO/NAOJ/NRAO), Marty et al, 2016; André, 2012; ARIEL – 13th Appleton Space Conference 5 THE SUN’S PLANETS ARE COLD SOME KEY O, C, N, S MOLECULES ARE NOT IN GAS FORM T ~ 150 K Image credit NASA Juno mission, NASA Galileo ARIEL – 13th Appleton Space Conference 6 WARM/HOT EXOPLANETS O, C, N, S (TI, VO, SI) MOLECULES ARE IN GAS FORM Atmospheric pressure 0.01Bar H2O gas CO2 gas CO gas CH4 gas HCN gas TiO gas T ~ 500-2500 K Condensates VO gas H2S gas 1 Bar Gases from interior ARIEL – 13th Appleton Space Conference 7 CHEMICAL MEASUREMENTS TODAY SPECTROSCOPIC OBSERVATIONS WITH CURRENT INSTRUMENTS (HUBBLE, SPITZER,SPHERE,GPI) • Precision of 20 ppm can be reached today by Hubble-WFC3 • Current data are sparse, instruments not absolutely calibrated • ~ 40 planets analysed -
The Longevity of Water Ice on Ganymedes and Europas Around Migrated Giant Planets
The Astrophysical Journal, 839:32 (9pp), 2017 April 10 https://doi.org/10.3847/1538-4357/aa67ea © 2017. The American Astronomical Society. All rights reserved. The Longevity of Water Ice on Ganymedes and Europas around Migrated Giant Planets Owen R. Lehmer1, David C. Catling1, and Kevin J. Zahnle2 1 Dept. of Earth and Space Sciences/Astrobiology Program, University of Washington, Seattle, WA, USA; [email protected] 2 NASA Ames Research Center, Moffett Field, CA, USA Received 2017 February 17; revised 2017 March 14; accepted 2017 March 18; published 2017 April 11 Abstract The gas giant planets in the Solar System have a retinue of icy moons, and we expect giant exoplanets to have similar satellite systems. If a Jupiter-like planet were to migrate toward its parent star the icy moons orbiting it would evaporate, creating atmospheres and possible habitable surface oceans. Here, we examine how long the surface ice and possible oceans would last before being hydrodynamically lost to space. The hydrodynamic loss rate from the moons is determined, in large part, by the stellar flux available for absorption, which increases as the giant planet and icy moons migrate closer to the star. At some planet–star distance the stellar flux incident on the icy moons becomes so great that they enter a runaway greenhouse state. This runaway greenhouse state rapidly transfers all available surface water to the atmosphere as vapor, where it is easily lost from the small moons. However, for icy moons of Ganymede’s size around a Sun-like star we found that surface water (either ice or liquid) can persist indefinitely outside the runaway greenhouse orbital distance. -
FINESSE and ARIEL + CASE: Dedicated Transit Spectroscopy Missions for the Post-TESS Era
FINESSE and ARIEL + CASE: Dedicated Transit Spectroscopy Missions for the Post-TESS Era Fast Infrared Exoplanet FINESSE Spectroscopy Survey Explorer Exploring the Diversity of New Worlds Around Other Stars Origins | Climate | Discovery Jacob Bean (University of Chicago) Presented on behalf of the FINESSE/CASE science team: Mark Swain (PI), Nicholas Cowan, Jonathan Fortney, Caitlin Griffith, Tiffany Kataria, Eliza Kempton, Laura Kreidberg, David Latham, Michael Line, Suvrath Mahadevan, Jorge Melendez, Julianne Moses, Vivien Parmentier, Gael Roudier, Evgenya Shkolnik, Adam Showman, Kevin Stevenson, Yuk Yung, & Robert Zellem Fast Infrared Exoplanet FINESSE Spectroscopy Survey Explorer Exploring the Diversity of New Worlds Around Other Stars **Candidate NASA MIDEX mission for launch in 2023** Objectives FINESSE will test theories of planetary origins and climate, transform comparative planetology, and open up exoplanet discovery space by performing a comprehensive, statistical, and uniform survey of transiting exoplanet atmospheres. Strategy • Transmission spectroscopy of 500 planets: Mp = few – 1,000 MEarth • Phase-resolved emission spectroscopy of a subset of 100 planets: Teq > 700 K • Focus on synergistic science with JWST: homogeneous survey, broader context, population properties, and bright stars Hardware • 75 cm aluminum Cassegrain telescope at L2 • 0.5 – 5.0 μm high-throughput prism spectrometer with R > 80 • Single HgCdTe detector with JWST heritage for science and guiding Origins | Climate | Discovery Advantages of Fast Infrared -
NASA Program & Budget Update
NASA Update AAAC Meeting | June 15, 2020 Paul Hertz Director, Astrophysics Division Science Mission Directorate @PHertzNASA Outline • Celebrate Accomplishments § Science Highlights § Mission Milestones • Committed to Improving § Inspiring Future Leaders, Fellowships § R&A Initiative: Dual Anonymous Peer Review • Research Program Update § Research & Analysis § ROSES-2020 Updates, including COVID-19 impacts • Missions Program Update § COVID-19 impact § Operating Missions § Webb, Roman, Explorers • Planning for the Future § FY21 Budget Request § Project Artemis § Creating the Future 2 NASA Astrophysics Celebrate Accomplishments 3 SCIENCE Exoplanet Apparently Disappears HIGHLIGHT in the Latest Hubble Observations Released: April 20, 2020 • What do astronomers do when a planet they are studying suddenly seems to disappear from sight? o A team of researchers believe a full-grown planet never existed in the first place. o The missing-in-action planet was last seen orbiting the star Fomalhaut, just 25 light-years away. • Instead, researchers concluded that the Hubble Space Telescope was looking at an expanding cloud of very fine dust particles from two icy bodies that smashed into each other. • Hubble came along too late to witness the suspected collision, but may have captured its aftermath. o This happened in 2008, when astronomers announced that Hubble took its first image of a planet orbiting another star. Caption o The diminutive-looking object appeared as a dot next to a vast ring of icy debris encircling Fomalhaut. • Unlike other directly imaged exoplanets, however, nagging Credit: NASA, ESA, and A. Gáspár and G. Rieke (University of Arizona) puzzles arose with Fomalhaut b early on. Caption: This diagram simulates what astronomers, studying Hubble Space o The object was unusually bright in visible light, but did not Telescope observations, taken over several years, consider evidence for the have any detectable infrared heat signature. -
Absolute Magnitude and Slope Parameter G Calibration of Asteroid 25143 Itokawa
Meteoritics & Planetary Science 44, Nr 12, 1849–1852 (2009) Abstract available online at http://meteoritics.org Absolute magnitude and slope parameter G calibration of asteroid 25143 Itokawa Fabrizio BERNARDI1, 2*, Marco MICHELI1, and David J. THOLEN1 1Institute for Astronomy, University of Hawai‘i, 2680 Woodlawn Drive, Honolulu, Hawai‘i 96822, USA 2Dipartimento di Matematica, Università di Pisa, Largo Pontecorvo 5, 56127 Pisa, Italy *Corresponding author. E-mail: [email protected] (Received 12 December 2008; revision accepted 27 May 2009) Abstract–We present results from an observing campaign of 25143 Itokawa performed with the 2.2 m telescope of the University of Hawai‘i between November 2000 and September 2001. The main goal of this paper is to determine the absolute magnitude H and the slope parameter G of the phase function with high accuracy for use in determining the geometric albedo of Itokawa. We found a value of H = 19.40 and a value of G = 0.21. INTRODUCTION empirical relation between a polarization curve and the albedo. Our work will take advantage by the post-encounter The present work was performed as part of our size determination obtained by Hayabusa, allowing a more collaboration with NASA to support the space mission direct conversion of the ground-based photometric Hayabusa (MUSES-C), which in September 2005 had a information into a physically meaningful value for the albedo. rendezvous with the near-Earth asteroid 25143 Itokawa. We Another important goal of these observations was to used the 2.2 m telescope of the University of Hawai‘i at collect more data for a possible future detection of the Mauna Kea. -
Our Solar System
Reader Moons of Our Solar System by Mick Roszel Genre Build Background Access Content Extend Language Expository • The Solar • Diagrams • Word Nonfi ction System • Captions Meanings • Planets and and Labels Moons • Glossary • Moon • Fact Box Geography Scott Foresman Reading Street 4.5.5 ì<(sk$m)=becbbi<ISBN 0-328-14211-5 +^-Ä-U-Ä-U 114211_CVR.indd4211_CVR.indd CCover1over1 33/8/05/8/05 99:26:20:26:20 PPMM Talk About It 1. What is a moon? 2. Look at the diagram on page 4. Describe three things itMoons shows about our of solar Oursystem. Write About It 3. How manySolar moons does S eachystem planet have? Make a graph on a separateby Micksheet Roszel of paper. Put one dot in the graph for each moon. 10 5 0 Mercury Venus Earth Mars Jupiter Extend Language A sphere is a round object, shaped like a ball or a planet. In sphere, pronounce the ph like f. Which of the following things can be called a sphere? the Earth’s moon a crater a soccer ball a coin Photographs Cover ©Omni-Photo Communications, Inc.; 1 ©Photo Researchers, Inc.; 2 ©Omni-Photo Communications, Inc.; 3 ©Bettmann/Corbis; 4 ©Luciano Corbella/DK Images; 5 (CR, BR) ©Corbis; 6 (CL) ©Photo Researchers, Inc., (BR) ©Tom Stack & Associates, Inc.; 7 ©Getty Images; 8 ©Digital Vision; 9 ©Jet Propulsion Laboratory/NASA; 10 ©Roger Ressmeyer/ NASA/Corbis. ISBN: 0-328-14211-5 Copyright © Pearson Education, Inc. All Rights Reserved. Printed in the United States of America. This publication is protected by Copyright, and permission should be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form by any means, electronic, mechanical, photocopying, recording, or likewise.