Advanced Technology for Direct Imaging of Exoplanets
Total Page：16
File Type：pdf, Size：1020Kb
Load more
Recommended publications
-
Mars Reconnaissance Orbiter
Chapter 6 Mars Reconnaissance Orbiter Jim Taylor, Dennis K. Lee, and Shervin Shambayati 6.1 Mission Overview The Mars Reconnaissance Orbiter (MRO) [1, 2] has a suite of instruments making observations at Mars, and it provides data-relay services for Mars landers and rovers. MRO was launched on August 12, 2005. The orbiter successfully went into orbit around Mars on March 10, 2006 and began reducing its orbit altitude and circularizing the orbit in preparation for the science mission. The orbit changing was accomplished through a process called aerobraking, in preparation for the “science mission” starting in November 2006, followed by the “relay mission” starting in November 2008. MRO participated in the Mars Science Laboratory touchdown and surface mission that began in August 2012 (Chapter 7). MRO communications has operated in three different frequency bands: 1) Most telecom in both directions has been with the Deep Space Network (DSN) at X-band (~8 GHz), and this band will continue to provide operational commanding, telemetry transmission, and radiometric tracking. 2) During cruise, the functional characteristics of a separate Ka-band (~32 GHz) downlink system were verified in preparation for an operational demonstration during orbit operations. After a Ka-band hardware anomaly in cruise, the project has elected not to initiate the originally planned operational demonstration (with yet-to-be used redundant Ka-band hardware). 201 202 Chapter 6 3) A new-generation ultra-high frequency (UHF) (~400 MHz) system was verified with the Mars Exploration Rovers in preparation for the successful relay communications with the Phoenix lander in 2008 and the later Mars Science Laboratory relay operations. -
A Review of Possible Planetary Atmospheres in the TRAPPIST-1 System
Space Sci Rev (2020) 216:100 https://doi.org/10.1007/s11214-020-00719-1 A Review of Possible Planetary Atmospheres in the TRAPPIST-1 System Martin Turbet1 · Emeline Bolmont1 · Vincent Bourrier1 · Brice-Olivier Demory2 · Jérémy Leconte3 · James Owen4 · Eric T. Wolf5 Received: 14 January 2020 / Accepted: 4 July 2020 / Published online: 23 July 2020 © The Author(s) 2020 Abstract TRAPPIST-1 is a fantastic nearby (∼39.14 light years) planetary system made of at least seven transiting terrestrial-size, terrestrial-mass planets all receiving a moderate amount of irradiation. To date, this is the most observationally favourable system of po- tentially habitable planets known to exist. Since the announcement of the discovery of the TRAPPIST-1 planetary system in 2016, a growing number of techniques and approaches have been used and proposed to characterize its true nature. Here we have compiled a state- of-the-art overview of all the observational and theoretical constraints that have been ob- tained so far using these techniques and approaches. The goal is to get a better understanding of whether or not TRAPPIST-1 planets can have atmospheres, and if so, what they are made of. For this, we surveyed the literature on TRAPPIST-1 about topics as broad as irradiation environment, planet formation and migration, orbital stability, effects of tides and Transit Timing Variations, transit observations, stellar contamination, density measurements, and numerical climate and escape models. Each of these topics adds a brick to our understand- ing of the likely—or on the contrary unlikely—atmospheres of the seven known planets of the system. -
Last Time: Planet Finding
Last Time: Planet Finding • Radial velocity method • Parent star’s Doppler shi • Planet minimum mass, orbital period, semi- major axis, orbital eccentricity • UnAl Kepler Mission, was the method with the most planets Last Time: Planet Finding • Transits – eclipse of the parent star: • Planetary radius, orbital period, semi-major axis • Now the most common way to find planets Last Time: Planet Finding • Direct Imaging • Planetary brightness, distance from parent star at that moment • About 10 planets detected Last Time: Planet Finding • Lensing • Planetary mass and, distance from parent star at that moment • You want to look towards the center of the galaxy where there is a high density of stars Last Time: Planet Finding • Astrometry • Tiny changes in star’s posiAon are not yet measurable • Would give you planet’s mass, orbit, and eccentricity One more important thing to add: • Giant planets (which are easiest to detect) are preferenAally found around stars that are abundant in iron – “metallicity” • Iron is the easiest heavy element to measure in a star • Heavy-element rich planetary systems make planets more easily 13.2 The Nature of Extrasolar Planets Our goals for learning: • What have we learned about extrasolar planets? • How do extrasolar planets compare with planets in our solar system? Measurable Properties • Orbital period, distance, and orbital shape • Planet mass, size, and density • Planetary temperature • Composition Orbits of Extrasolar Planets • Nearly all of the detected planets have orbits smaller than Jupiter’s. • This is a selection effect: Planets at greater distances are harder to detect with the Doppler technique. Orbits of Extrasolar Planets • Orbits of some extrasolar planets are much more elongated (have a greater eccentricity) than those in our solar system. -
Survival of Satellites During the Migration of a Hot Jupiter: the Influence of Tides
EPSC Abstracts Vol. 13, EPSC-DPS2019-1590-1, 2019 EPSC-DPS Joint Meeting 2019 c Author(s) 2019. CC Attribution 4.0 license. Survival of satellites during the migration of a Hot Jupiter: the influence of tides Emeline Bolmont (1), Apurva V. Oza (2), Sergi Blanco-Cuaresma (3), Christoph Mordasini (2), Pierre Auclair-Desrotour (2), Adrien Leleu (2) (1) Observatoire de Genève, Université de Genève, 51 Chemin des Maillettes, CH-1290 Sauverny, Switzerland ([email protected]) (2) Physikalisches Institut, Universität Bern, Gesellschaftsstr. 6, 3012, Bern, Switzerland (3) Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA Abstract 2. The model We explore the origin and stability of extrasolar satel- lites orbiting close-in gas giants, by investigating if the Tidal interactions 1 M⊙ satellite can survive the migration of the planet in the 1 MIo protoplanetary disk. To accomplish this objective, we 1 MJup used Posidonius, a N-Body code with an integrated tidal model, which we expanded to account for the migration of the gas giant in a disk. Preliminary re- Inner edge of disk: ain sults suggest the survival of the satellite is rare, which Type 2 migration: !mig would indicate that if such satellites do exist, capture is a more likely process. Figure 1: Schema of the simulation set up: A Io-like satellite orbits around a Jupiter-like planet with a solar- 1. Introduction like host star. Satellites around Hot Jupiters were first thought to be lost by falling onto their planet over Gyr timescales (e.g. [1]). This is due to the low tidal dissipation factor of Jupiter (Q 106, [10]), likely to be caused by the 2.1. -
Mro High Resolution Imaging Science Experiment (Hirise)
Sixth International Conference on Mars (2003) 3287.pdf MROHIGHRESOLUTIONIMAGINGSCIENCEEXPERIMENT(HIRISE): INSTRUMENTDEVELOPMENT.AlanDelamere,IraBecker,JimBergstrom,JonBurkepile,Joe Day,DavidDorn,DennisGallagher,CharlieHamp,JeffreyLasco,BillMeiers,AndrewSievers,Scott StreetmanStevenTarr,MarkTommeraasen,PaulVolmer.BallAerospaceandTechnologyCorp.,PO Box1062,Boulder,CO80306 Focus Introduction:Theprimaryfunctionalre- Mechanism PrimaryMirror quirementoftheHiRISEimager,figure1isto PrimaryMirrorBaffle 2nd Fold allowidentificationofbothpredictedandun- Mirror knownfeaturesonthesurfaceofMarstoa muchfinerresolutionandcontrastthanprevi- ouslypossible[1],[2].Thisresultsinacam- 1st Fold erawithaverywideswathwidth,6kmat Mirror 300kmaltitude,andahighsignaltonoise ratio,>100:1.Generationofterrainmaps,30 Filters cmverticalresolution,fromstereoimages Focal requiresveryaccurategeometriccalibration. Plane Theprojectlimitationsofmass,costand schedulemakethedevelopmentchallenging. FocalPlane SecondaryMirror Inaddition,thespacecraftstability[3]must Electronics TertiaryMirror SecondaryMirrorBaffle notbeamajorlimitationtoimagequality. Thenominalorbitforthesciencephaseofthe missionisa3pmorbitof255by320kmwith Figure1Cameraopticalpathoptimizedforlowmass periapsislockedtothesouthpole.Thetrack Integration(TDI)tocreateveryhigh(100:1)signalnoise velocityisapproximately3,400m/s. ratioimages. HiRISEFeatures:TheHiRISEinstrumentperformance Theimagerdesignisanall-reflectivethreemirrorastig- goalsarelistedinTable1.Thedesignfeaturesa50cm matictelescopewithlight-weightedZeroduropticsanda -
The Space Environment and Atmospheric Joule Heating of the Habitable Zone Exoplanet TOI 700 D
The Astrophysical Journal, 897:101 (11pp), 2020 July 1 https://doi.org/10.3847/1538-4357/ab9637 © 2020. The American Astronomical Society. All rights reserved. The Space Environment and Atmospheric Joule Heating of the Habitable Zone Exoplanet TOI 700 d Ofer Cohen1 , C. Garraffo2,3 ,Sofia-Paraskevi Moschou3 , Jeremy J. Drake3 , J. D. Alvarado-Gómez4 , Alex Glocer5, and Federico Fraschetti6 1 Lowell Center for Space Science and Technology, University of Massachusetts Lowell, 600 Suffolk Street, Lowell, MA 01854, USA; [email protected] 2 Institute for Applied Computational Science, Harvard University, 33 Oxford Street, Cambridge, MA, USA 3 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA, USA 4 Leibniz Institute for Astrophysics Potsdam, An der Sternwarte 16, D-14482 Potsdam, Germany 5 NASA Goddard Space Flight Center, Greenbelt, MD, USA 6 Dept. of Planetary Sciences-Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA Received 2020 February 22; revised 2020 May 5; accepted 2020 May 23; published 2020 July 7 Abstract We investigate the space environment conditions near the Earth-size planet TOI700d using a set of numerical models for the stellar corona and wind, the planetary magnetosphere, and the planetary ionosphere. We drive our simulations using a scaled-down stellar input and a scaled-up solar input in order to obtain two independent solutions. We find that for the particular parameters used in our study, the stellar wind conditions near the planet are not very extreme—slightly stronger than that near the Earth in terms of the stellar wind ram pressure and the intensity of the interplanetary magnetic field. -
Exploring Exoplanet Populations with NASA's Kepler Mission
SPECIAL FEATURE: PERSPECTIVE PERSPECTIVE SPECIAL FEATURE: Exploring exoplanet populations with NASA’s Kepler Mission Natalie M. Batalha1 National Aeronautics and Space Administration Ames Research Center, Moffett Field, 94035 CA Edited by Adam S. Burrows, Princeton University, Princeton, NJ, and accepted by the Editorial Board June 3, 2014 (received for review January 15, 2014) The Kepler Mission is exploring the diversity of planets and planetary systems. Its legacy will be a catalog of discoveries sufficient for computing planet occurrence rates as a function of size, orbital period, star type, and insolation flux.The mission has made significant progress toward achieving that goal. Over 3,500 transiting exoplanets have been identified from the analysis of the first 3 y of data, 100 planets of which are in the habitable zone. The catalog has a high reliability rate (85–90% averaged over the period/radius plane), which is improving as follow-up observations continue. Dynamical (e.g., velocimetry and transit timing) and statistical methods have confirmed and characterized hundreds of planets over a large range of sizes and compositions for both single- and multiple-star systems. Population studies suggest that planets abound in our galaxy and that small planets are particularly frequent. Here, I report on the progress Kepler has made measuring the prevalence of exoplanets orbiting within one astronomical unit of their host stars in support of the National Aeronautics and Space Admin- istration’s long-term goal of finding habitable environments beyond the solar system. planet detection | transit photometry Searching for evidence of life beyond Earth is the Sun would produce an 84-ppm signal Translating Kepler’s discovery catalog into one of the primary goals of science agencies lasting ∼13 h. -
The Search for Exomoons and the Characterization of Exoplanet Atmospheres
Corso di Laurea Specialistica in Astronomia e Astrofisica The search for exomoons and the characterization of exoplanet atmospheres Relatore interno : dott. Alessandro Melchiorri Relatore esterno : dott.ssa Giovanna Tinetti Candidato: Giammarco Campanella Anno Accademico 2008/2009 The search for exomoons and the characterization of exoplanet atmospheres Giammarco Campanella Dipartimento di Fisica Università degli studi di Roma “La Sapienza” Associate at Department of Physics & Astronomy University College London A thesis submitted for the MSc Degree in Astronomy and Astrophysics September 4th, 2009 Università degli Studi di Roma ―La Sapienza‖ Abstract THE SEARCH FOR EXOMOONS AND THE CHARACTERIZATION OF EXOPLANET ATMOSPHERES by Giammarco Campanella Since planets were first discovered outside our own Solar System in 1992 (around a pulsar) and in 1995 (around a main sequence star), extrasolar planet studies have become one of the most dynamic research fields in astronomy. Our knowledge of extrasolar planets has grown exponentially, from our understanding of their formation and evolution to the development of different methods to detect them. Now that more than 370 exoplanets have been discovered, focus has moved from finding planets to characterise these alien worlds. As well as detecting the atmospheres of these exoplanets, part of the characterisation process undoubtedly involves the search for extrasolar moons. The structure of the thesis is as follows. In Chapter 1 an historical background is provided and some general aspects about ongoing situation in the research field of extrasolar planets are shown. In Chapter 2, various detection techniques such as radial velocity, microlensing, astrometry, circumstellar disks, pulsar timing and magnetospheric emission are described. A special emphasis is given to the transit photometry technique and to the two already operational transit space missions, CoRoT and Kepler. -
Open Engagment Group A
Habitable Worlds 2021 Workshop Open Engagement – Group B Abstract Title 1st Author # 19 Obliquity Variation of Circumbinary Planets Gongjie Li Removing Stellar Activity Signals from Radial 34 Zoe de Beurs Velocity Measurements Using Neural Networks 40 Dayside land on tidally locked M-Earths Evelyn Macdonald Effect of mantle oxidation state on the magma ocean 87 Nisha Katyal atmospheric evolution Stellar Variability & Precision Radial Velocimetry: 89 Eric Ford Lessons for atmospheric characterization Is there any other habitable planets in universe 91 Md Redyan Ahmed except Earth? Stellar Energetic Particle-driven Production of Biologically Relevant Molecules in Atmospheres of 93 Guillaume Gronoff Young Earth-like Exoplanets Around Active G-K Stars 97 Stable, Closely-Spaced Three-Planet Systems Sacha Gavino Ground-Based Exoplanet Direct Imaging in the Next 98 Thayne Currie Decade: The Path to Imaging Another Earth Magma ocean differentiation regime in the earliest 101 Damanveer Grewal formed rocky bodies -Internal or External? A very early origin of isotopically distinct nitrogen 102 Damanveer Grewal in the inner Solar System protoplanets XUV-Driven Atmospheric Mass Loss of M Dwarf 103 Laura Amaral Planets due to Flaring Impact of Tides on the Potential for Exoplanets to 104 Armen Tokadjian Host Exomoons 105 Drifting into habitability Bradley Hansen 106 How to Detect a Dead Planet Sara Walker Computational study on the importance of UV light 107 in the production of molecules of prebiotic Marion Armas Vazquez importance in an astrobiological -
Can Brown Dwarfs Survive on Close Orbits Around Convective Stars? C
A&A 589, A55 (2016) Astronomy DOI: 10.1051/0004-6361/201527100 & c ESO 2016 Astrophysics Can brown dwarfs survive on close orbits around convective stars? C. Damiani1 and R. F. Díaz2 1 Université Paris-Sud, CNRS, Institut d’Astrophysique Spatiale, UMR8617, 91405 Orsay Cedex, France e-mail: [email protected] 2 Observatoire astronomique de l’Université de Genève, 51 ch. des Maillettes, 1290 Versoix, Switzerland e-mail: [email protected] Received 1 August 2015 / Accepted 23 February 2016 ABSTRACT Context. The mass range of brown dwarfs extends across the planetary domain to stellar objects. There is a relative paucity of brown dwarfs companions around FGKM-type stars compared to exoplanets for orbital periods of less than a few years, but most of the short-period brown dwarf companions that are fully characterised by transits and radial velocities are found around F-type stars. Aims. We examine the hypothesis that brown dwarf companions could not survive on close orbit around stars with important convec- tive envelopes because the tides and angular momentum loss, the result of magnetic braking, would lead to a rapid orbital decay with the companion being quickly engulfed. Methods. We use a classical Skumanich-type braking law and constant time-lag tidal theory to assess the characteristic timescale for orbital decay for the brown dwarf mass range as a function of the host properties. Results. We find that F-type stars may host massive companions for a significantly longer time than G-type stars for a given orbital period, which may explain the paucity of G-type hosts for brown dwarfs with an orbital period less than five days. -
Canopus XVII Básicamente La Escribió Él
N° 17 ENE 2020 rreevviissttaa ccaannooppuuss LA REVISTA DE COMUNICACIÓN CIENTÍFICA EDITORIAL Empezamos un nuevo año, 2020, siempre que cambia ese número, el común de las personas siente una renovación, nuevos objetivos, nuevo “aire” como comúnmente se dice. Por nuestra parte, en este enero 2020 estamos mucho mejor parados que en enero del año pasado, de hecho hace un año no hubo publicaciones, comenzamos en febrero con el número V cuando asumí la dirección editorial de este medio digital. Vale destacar algo que no mencionamos en el número pasado, hubo cambio de gestión y organigrama. El Complejo Planetario Malargüe no es más una dirección, si no que es una coordinación. Dicha coordinación, de Marcelo Salvadores depende de la dirección de Industrias y Negocios municipales, a cargo de Marilé Verón. Subiendo un escalón más está la Secretaría Rural, Tecnología Ciencia e Innovación bajo el mando de nuestro ex compañero, César Ojeda, a quien felicitamos desde nuestro pequeño espacio conformado por Agustín y yo. Como hemos ido haciendo estos últimos meses, se ha incrementado la cantidad de contenido, lo que nos lleva a agregar más páginas, digitales por suerte a esta revista. Este número supera las 70 páginas y hablamos de temáticas muy variadas. Quiero agradecer a Agustín, ya que desde el 10 de diciembre soy Coordinador Científico del Planetario, y, por temas de temporada y arreglos, el estar ocupado en esos temas, no he podido dedicarme a la escritura. Canopus XVII básicamente la escribió él. Comenzamos el año con la noticia de que ¡Argentina tiene un planeta! No es tan literal, pero sí que pudimos nombrar a uno, el concurso fue desde la UAI y canalizado desde el Nodo Nacional Argentino para la difusión de la Astronomía, donde el Planetario fue parte. -
Ground-Based Secondary Eclipse Detection of the Very-Hot Jupiter OGLE-TR-56B
A&A 493, L31–L34 (2009) Astronomy DOI: 10.1051/0004-6361:200811268 & c ESO 2009 Astrophysics Letter to the Editor Ground-based secondary eclipse detection of the very-hot Jupiter OGLE-TR-56b D. K. Sing1 and M. López-Morales2, 1 Institut d’Astrophysique de Paris, CNRS/UPMC, 98bis boulevard Arago, 75014 Paris, France e-mail: [email protected] 2 Carnegie Institution of Washington, Dept. of Terrestrial Magnetism, 5241 Broad Branch Road NW, Washington, DC 20015, USA e-mail: [email protected] Received 31 October 2008 / Accepted 21 November 2008 ABSTRACT We report on the detection of the secondary eclipse of the very-hot Jupiter OGLE-TR-56b from combined z-band time series pho- tometry obtained with the VLT and Magellan telescopes. We measure a flux decrement of 0.0363 ± 0.0091% from the combined +127 Magellan and VLT datasets, which indicates a blackbody brightness temperature of 2718−107 K, a very low albedo, and a small in- cident radiation redistribution factor, indicating a lack of strong winds in the planet’s atmosphere. The measured secondary depth is consistent with thermal emission, but our precision is not sufficient to distinguish between a black-body emitting planet, or emission as predicted by models with strong optical absorbers such as TiO/VO. This is the first time that thermal emission from an extrasolar planet is detected at optical wavelengths and with ground-based telescopes. Key words. binaries: eclipsing – planetary systems – stars: individual: OGLE-TR-56 – techniques: photometric 1. Introduction Here we present the results of the follow-up observations to test that prediction.