Precise Radial Velocities of Giant Stars
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The Discovery of Exoplanets
L'Univers, S´eminairePoincar´eXX (2015) 113 { 137 S´eminairePoincar´e New Worlds Ahead: The Discovery of Exoplanets Arnaud Cassan Universit´ePierre et Marie Curie Institut d'Astrophysique de Paris 98bis boulevard Arago 75014 Paris, France Abstract. Exoplanets are planets orbiting stars other than the Sun. In 1995, the discovery of the first exoplanet orbiting a solar-type star paved the way to an exoplanet detection rush, which revealed an astonishing diversity of possible worlds. These detections led us to completely renew planet formation and evolu- tion theories. Several detection techniques have revealed a wealth of surprising properties characterizing exoplanets that are not found in our own planetary system. After two decades of exoplanet search, these new worlds are found to be ubiquitous throughout the Milky Way. A positive sign that life has developed elsewhere than on Earth? 1 The Solar system paradigm: the end of certainties Looking at the Solar system, striking facts appear clearly: all seven planets orbit in the same plane (the ecliptic), all have almost circular orbits, the Sun rotation is perpendicular to this plane, and the direction of the Sun rotation is the same as the planets revolution around the Sun. These observations gave birth to the Solar nebula theory, which was proposed by Kant and Laplace more that two hundred years ago, but, although correct, it has been for decades the subject of many debates. In this theory, the Solar system was formed by the collapse of an approximately spheric giant interstellar cloud of gas and dust, which eventually flattened in the plane perpendicular to its initial rotation axis. -
Searching for Trends in Atmospheric Compositions of Extrasolar Planets Kassandra Weber Humboldt State University
IdeaFest: Interdisciplinary Journal of Creative Works and Research from Humboldt State University Volume 3 ideaFest: Interdisciplinary Journal of Creative Works and Research from Humboldt State Article 2 University 2019 Searching for Trends in Atmospheric Compositions of Extrasolar Planets Kassandra Weber Humboldt State University Paola Rodriguez Hidalgo University of Washington Bothell Adam Turk Humboldt State University Troy Maloney Humboldt State University Stephen Kane University of California, Riverside Follow this and additional works at: https://digitalcommons.humboldt.edu/ideafest Part of the Other Astrophysics and Astronomy Commons Recommended Citation Weber, Kassandra; Rodriguez Hidalgo, Paola; Turk, Adam; Maloney, Troy; and Kane, Stephen (2019) "Searching for Trends in Atmospheric Compositions of Extrasolar Planets," IdeaFest: Interdisciplinary Journal of Creative Works and Research from Humboldt State University: Vol. 3 , Article 2. Available at: https://digitalcommons.humboldt.edu/ideafest/vol3/iss1/2 This Article is brought to you for free and open access by the Journals at Digital Commons @ Humboldt State University. It has been accepted for inclusion in IdeaFest: Interdisciplinary Journal of Creative Works and Research from Humboldt State University by an authorized editor of Digital Commons @ Humboldt State University. For more information, please contact [email protected]. ASTRONOMY Searching for Trends in Atmospheric Compositions of Extrasolar Planets Kassandra Weber1*, Paola Rodríguez Hidalgo2, Adam Turk1, Troy Maloney1, Stephen Kane3 ABSTRACT—Since the first exoplanet was discovered decades ago, there has been a rapid evolution of the study of planets found beyond our solar system. A considerable amount of data has been collected on the nearly 3,838 confirmed exoplanets found to date. Recent findings regarding transmission spectroscopy, a method that measures a planet’s upper atmosphere to determine its composition, have been published on a limited number of exoplanets. -
Enabling Science with Gaia Observations of Naked-Eye Stars
Enabling science with Gaia observations of naked-eye stars J. Sahlmanna,b, J. Mart´ın-Fleitasb,c, A. Morab,c, A. Abreub,d, C. M. Crowleyb,e, E. Jolietb,f aEuropean Space Agency, STScI, 3700 San Martin Drive, Baltimore, MD 21218, USA; bEuropean Space Agency, ESAC, P.O. Box 78, Villanueva de la Canada,˜ 28691 Madrid, Spain; cAurora Technology, Crown Business Centre, Heereweg 345, 2161 CA Lisse, The Netherlands; dElecnor Deimos Space, Ronda de Poniente 19, Ed. Fiteni VI, 28760 Tres Cantos, Madrid, Spain; eHE Space Operations BV, Huygensstraat 44, 2201 DK Noordwijk, The Netherlands; fCalifornia Institute of Technology, Pasadena, CA, 91125, USA ABSTRACT ESA’s Gaia space astrometry mission is performing an all-sky survey of stellar objects. At the beginning of the nominal mission in July 2014, an operation scheme was adopted that enabled Gaia to routinely acquire observations of all stars brighter than the original limit of G∼6, i.e. the naked-eye stars. Here, we describe the current status and extent of those observations and their on-ground processing. We present an overview of the data products generated for G<6 stars and the potential scientific applications. Finally, we discuss how the Gaia survey could be enhanced by further exploiting the techniques we developed. Keywords: Gaia, Astrometry, Proper motion, Parallax, Bright Stars, Extrasolar planets, CCD 1. INTRODUCTION There are about 6000 stars that can be observed with the unaided human eye. Greek astronomer Hipparchus used these stars to define the magnitude system still in use today, in which the faintest stars had an apparent visual magnitude of 6. -
Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
Tímaákvarðanir Á Myrkvum Valinna Myrkvatvístirna Og Þvergöngum Fjarreikistjarna, Árin 2017-2018, Og Fjarlægðamælingar
Tímaákvarðanir á myrkvum valinna myrkvatvístirna, þvergöngum fjarreikistjarna og fjarlægðamælingar, árin 2017—2018 Snævarr Guðmundsson 2019 Náttúrustofa Suðausturlands Litlubrú 2, 780 Höfn í Hornafirði Nýheimar, Litlubrú 2 780 Höfn Í Hornafirði www.nattsa.is Skýrsla nr. Dagsetning Dreifing NattSA 2019-04 10. apríl 2019 Opin Fjöldi síðna 109 Tímaákvarðanir á myrkvum valinna myrkvatvístirna, Fjöldi mynda 229 þvergöngum fjarreikistjarna og fjarlægðamælingar, árin 2017- 2018. Verknúmer 1280 Höfundur: Snævarr Guðmundsson Verkefnið var styrkt af Prófarkarlestur Þorsteinn Sæmundsson, Kristín Hermannsdóttir og Lilja Jóhannesdóttir Útdráttur Hér er gert grein fyrir stjörnuathugunum á Hornafirði á árabilinu 2017 til loka árs 2018. Í flestum tilfellum voru viðfangsefnin óeiginlegar breytistjörnur, aðallega myrkvatvístirni, en einnig var fylgst með nokkrum fjarreikistjörnum. Í mælingum á myrkvatvístirnum og fjarreikistjörnum er markmiðið að tímasetja myrkva og þvergöngur. Einnig er sagt frá niðurstöðum á nándarstjörnunni Ross 248 og athugunum á lausþyrpingunni NGC 7790 og breytistjörnum í nágrenni hennar. Markmið mælinga á nándarstjörnu og lausþyrpingum er að meta fjarlægðir eða aðra eiginleika fyrirbæranna. Að lokum eru kynntar athuganir á litrófi nokkurra bjartra stjarna. Í samantektinni er sagt frá hverju viðfangsefni í sérköflum. Þessi samantekt er sú þriðja um stjörnuathuganir sem er gefin út af Náttúrustofu Suðausturlands. Niðurstöður hafa verið sendar í alþjóðlegan gagnagrunn þar sem þær, ásamt fjölda sambærilegra mæligagna frá stjörnuáhugamönnum, eru aðgengilegar stjarnvísindasamfélaginu. Hægt er að sækja skýrslur um stjörnuathuganir á vefslóðina: http://nattsa.is/utgefid-efni/. Lykilorð: myrkvatvístirni, fjarreikistjörnur, breytistjörnur, lausþyrpingar, ljósmælingar, fjarlægðir stjarna, litróf stjarna. ii Tímaákvarðanir á myrkvum valinna myrkvatvístirna, þvergöngum fjarreikistjarna og fjarlægðamælingar, árin 2017-2018. — Annáll 2017-2018. Timings of selected eclipsing binaries, exoplanet transits and distance measurements in 2017- 2018. -
Gaia Search for Stellar Companions of TESS Objects of Interest
Received 1 July 2020; Revised 29 August 2020; Accepted 18 September 2020 DOI: xxx/xxxx ARTICLE TYPE Gaia Search for stellar Companions of TESS Objects of Interest M. Mugrauer* | K.-U. Michel 1Astrophysikalisches Institut und Universitäts-Sternwarte Jena The first results of a new survey are reported, which explores the 2nd data release Correspondence of the ESA-Gaia mission, in order to search for stellar companions of (Community) M. Mugrauer, Astrophysikalisches Institut und Universitäts-Sternwarte Jena, TESS Objects of Interest and to characterize their properties. In total, 193 binary and Schillergäßchen 2, D-07745 Jena, Germany. 15 hierarchical triple star systems are presented, detected among 1391 target stars, Email: [email protected] which are located at distances closer than about 500 pc around the Sun. The com- panions and the targets are equidistant and share a common proper motion, as it is expected for gravitationally bound stellar systems, proven with their accurate Gaia astrometry. The companions exhibit masses in the range between about 0.08 M⊙ and 3 M⊙ and are most frequently found in the mass range between 0.13 and 0.6 M⊙. The companions are separated from the targets by about 40 up to 9900 au, and their frequency continually decreases with increasing separation. While most of the detected companions are late K to mid M dwarfs, also 5 white dwarf companions were identified in this survey, whose true nature is revealed by their photometric properties. KEYWORDS: binaries: visual, white dwarfs, stars: individual (TOI 249 C, TOI 1259 B, TOI 1624 B, TOI 1703 B, CTOI 53309262 B) 1 INTRODUCTION explored the 2nd data release of the European Space Agency (ESA) Gaia mission (Gaia DR2 from hereon, Gaia Collabora- A key aspect in the diversity of exoplanets is the multiplicity tion, Brown, Vallenari, et al., 2018), which provides manifold of their host stars. -
Lecture 3 - Minimum Mass Model of Solar Nebula
Lecture 3 - Minimum mass model of solar nebula o Topics to be covered: o Composition and condensation o Surface density profile o Minimum mass of solar nebula PY4A01 Solar System Science Minimum Mass Solar Nebula (MMSN) o MMSN is not a nebula, but a protoplanetary disc. Protoplanetary disk Nebula o Gives minimum mass of solid material to build the 8 planets. PY4A01 Solar System Science Minimum mass of the solar nebula o Can make approximation of minimum amount of solar nebula material that must have been present to form planets. Know: 1. Current masses, composition, location and radii of the planets. 2. Cosmic elemental abundances. 3. Condensation temperatures of material. o Given % of material that condenses, can calculate minimum mass of original nebula from which the planets formed. • Figure from Page 115 of “Physics & Chemistry of the Solar System” by Lewis o Steps 1-8: metals & rock, steps 9-13: ices PY4A01 Solar System Science Nebula composition o Assume solar/cosmic abundances: Representative Main nebular Fraction of elements Low-T material nebular mass H, He Gas 98.4 % H2, He C, N, O Volatiles (ices) 1.2 % H2O, CH4, NH3 Si, Mg, Fe Refractories 0.3 % (metals, silicates) PY4A01 Solar System Science Minimum mass for terrestrial planets o Mercury:~5.43 g cm-3 => complete condensation of Fe (~0.285% Mnebula). 0.285% Mnebula = 100 % Mmercury => Mnebula = (100/ 0.285) Mmercury = 350 Mmercury o Venus: ~5.24 g cm-3 => condensation from Fe and silicates (~0.37% Mnebula). =>(100% / 0.37% ) Mvenus = 270 Mvenus o Earth/Mars: 0.43% of material condensed at cooler temperatures. -
Exoplanet Discovery Methods (1) Direct Imaging Today: Star Wobbles (2) Astrometry → Position (3) Radial Velocity → Velocity
Exoplanet Discovery Methods (1) Direct imaging Today: Star Wobbles (2) Astrometry → position (3) Radial velocity → velocity Later: (4) Transits (5) Gravitational microlensing (6) Pulsar timing Kepler Orbits Kepler 1: Planet orbit is an ellipse with star at one focus Star’s view: (Newton showed this is due to gravity’s inverse-square law). Kepler 2: Planet seeps out equal area in equal time (angular momentum conservation). Planet’s view: Planet at the focus. Star sweeps equal area in equal time Inertial Frame: Star and planet both orbit around the centre of mass. Kepler Orbits M = M" + mp = total mass a = ap + a" = semi # major axis ap mp = a" M" = a M Centre of Mass P = orbit period a b a % P ( 2 a3 = G M ' * Kepler's 3rd Law b & 2$ ) a - b e + = eccentricity 0 = circular 1 = parabolic a ! Astrometry • Look for a periodic “wobble” in the angular position of host star • Light from the star+planet is dominated by star • Measure star’s motion in the plane of the sky due to the orbiting planet • Must correct measurements for parallax and proper motion of star • Doppler (radial velocity) more sensitive to planets close to the star • Astrometry more sensitive to planets far from the star Stellar wobble: Star and planet orbit around centre of mass. Radius of star’s orbit scales with planet’s mass: a m a M * = p p = * a M* + mp a M* + mp Angular displacement for a star at distance d: a & mp ) & a) "# = $ % ( + ( + ! d ' M* * ' d* (Assumes small angles and mp << M* ) ! Scaling to Jupiter and the Sun, this gives: ,1 -1 % mp ( % M ( % a ( % d ( "# $ 0.5 ' * ' + * ' * ' * mas & mJ ) & Msun ) & 5AU) & 10pc) Note: • Units are milliarcseconds -> very small effect • Amplitude increases at large orbital separation, a ! • Amplitude decreases with distance to star d. -
Exep Science Plan Appendix (SPA) (This Document)
ExEP Science Plan, Rev A JPL D: 1735632 Release Date: February 15, 2019 Page 1 of 61 Created By: David A. Breda Date Program TDEM System Engineer Exoplanet Exploration Program NASA/Jet Propulsion Laboratory California Institute of Technology Dr. Nick Siegler Date Program Chief Technologist Exoplanet Exploration Program NASA/Jet Propulsion Laboratory California Institute of Technology Concurred By: Dr. Gary Blackwood Date Program Manager Exoplanet Exploration Program NASA/Jet Propulsion Laboratory California Institute of Technology EXOPDr.LANET Douglas Hudgins E XPLORATION PROGRAMDate Program Scientist Exoplanet Exploration Program ScienceScience Plan Mission DirectorateAppendix NASA Headquarters Karl Stapelfeldt, Program Chief Scientist Eric Mamajek, Deputy Program Chief Scientist Exoplanet Exploration Program JPL CL#19-0790 JPL Document No: 1735632 ExEP Science Plan, Rev A JPL D: 1735632 Release Date: February 15, 2019 Page 2 of 61 Approved by: Dr. Gary Blackwood Date Program Manager, Exoplanet Exploration Program Office NASA/Jet Propulsion Laboratory Dr. Douglas Hudgins Date Program Scientist Exoplanet Exploration Program Science Mission Directorate NASA Headquarters Created by: Dr. Karl Stapelfeldt Chief Program Scientist Exoplanet Exploration Program Office NASA/Jet Propulsion Laboratory California Institute of Technology Dr. Eric Mamajek Deputy Program Chief Scientist Exoplanet Exploration Program Office NASA/Jet Propulsion Laboratory California Institute of Technology This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. © 2018 California Institute of Technology. Government sponsorship acknowledged. Exoplanet Exploration Program JPL CL#19-0790 ExEP Science Plan, Rev A JPL D: 1735632 Release Date: February 15, 2019 Page 3 of 61 Table of Contents 1. -
Exoplanetary Atmospheres: Key Insights, Challenges, and Prospects
AA57CH15_Madhusudhan ARjats.cls August 7, 2019 14:11 Annual Review of Astronomy and Astrophysics Exoplanetary Atmospheres: Key Insights, Challenges, and Prospects Nikku Madhusudhan Institute of Astronomy, University of Cambridge, Cambridge CB3 0HA, United Kingdom; email: [email protected] Annu. Rev. Astron. Astrophys. 2019. 57:617–63 Keywords The Annual Review of Astronomy and Astrophysics is extrasolar planets, spectroscopy, planet formation, habitability, atmospheric online at astro.annualreviews.org composition https://doi.org/10.1146/annurev-astro-081817- 051846 Abstract Copyright © 2019 by Annual Reviews. Exoplanetary science is on the verge of an unprecedented revolution. The All rights reserved thousands of exoplanets discovered over the past decade have most recently been supplemented by discoveries of potentially habitable planets around nearby low-mass stars. Currently, the field is rapidly progressing toward de- tailed spectroscopic observations to characterize the atmospheres of these planets. Various surveys from space and the ground are expected to detect numerous more exoplanets orbiting nearby stars that make the planets con- ducive for atmospheric characterization. The current state of this frontier of exoplanetary atmospheres may be summarized as follows. We have entered the era of comparative exoplanetology thanks to high-fidelity atmospheric observations now available for tens of exoplanets. Access provided by Florida International University on 01/17/21. For personal use only. Annu. Rev. Astron. Astrophys. 2019.57:617-663. Downloaded from www.annualreviews.org Recent studies reveal a rich diversity of chemical compositions and atmospheric processes hitherto unseen in the Solar System. Elemental abundances of exoplanetary atmospheres place impor- tant constraints on exoplanetary formation and migration histories. -
On the Detection of Exoplanets Via Radial Velocity Doppler Spectroscopy
The Downtown Review Volume 1 Issue 1 Article 6 January 2015 On the Detection of Exoplanets via Radial Velocity Doppler Spectroscopy Joseph P. Glaser Cleveland State University Follow this and additional works at: https://engagedscholarship.csuohio.edu/tdr Part of the Astrophysics and Astronomy Commons How does access to this work benefit ou?y Let us know! Recommended Citation Glaser, Joseph P.. "On the Detection of Exoplanets via Radial Velocity Doppler Spectroscopy." The Downtown Review. Vol. 1. Iss. 1 (2015) . Available at: https://engagedscholarship.csuohio.edu/tdr/vol1/iss1/6 This Article is brought to you for free and open access by the Student Scholarship at EngagedScholarship@CSU. It has been accepted for inclusion in The Downtown Review by an authorized editor of EngagedScholarship@CSU. For more information, please contact [email protected]. Glaser: Detection of Exoplanets 1 Introduction to Exoplanets For centuries, some of humanity’s greatest minds have pondered over the possibility of other worlds orbiting the uncountable number of stars that exist in the visible universe. The seeds for eventual scientific speculation on the possibility of these "exoplanets" began with the works of a 16th century philosopher, Giordano Bruno. In his modernly celebrated work, On the Infinite Universe & Worlds, Bruno states: "This space we declare to be infinite (...) In it are an infinity of worlds of the same kind as our own." By the time of the European Scientific Revolution, Isaac Newton grew fond of the idea and wrote in his Principia: "If the fixed stars are the centers of similar systems [when compared to the solar system], they will all be constructed according to a similar design and subject to the dominion of One." Due to limitations on observational equipment, the field of exoplanetary systems existed primarily in theory until the late 1980s. -
The TOI-763 System: Sub-Neptunes Orbiting a Sun-Like Star
MNRAS 000,1–14 (2020) Preprint 31 August 2020 Compiled using MNRAS LATEX style file v3.0 The TOI-763 system: sub-Neptunes orbiting a Sun-like star M. Fridlund1;2?, J. Livingston3, D. Gandolfi4, C. M. Persson2, K. W. F. Lam5, K. G. Stassun6, C. Hellier 7, J. Korth8, A. P. Hatzes9, L. Malavolta10, R. Luque11;12, S. Redfield 13, E. W. Guenther9, S. Albrecht14, O. Barragan15, S. Benatti16, L. Bouma17, J. Cabrera18, W.D. Cochran19;20, Sz. Csizmadia18, F. Dai21;17, H. J. Deeg11;12, M. Esposito9, I. Georgieva2, S. Grziwa8, L. González Cuesta11;12, T. Hirano22, J. M. Jenkins23, P. Kabath24, E. Knudstrup14, D.W. Latham25, S. Mathur11;12, S. E. Mullally32, N. Narita26;27;28;29;11, G. Nowak11;12, A. O. H. Olofsson 2, E. Palle11;12, M. Pätzold8, E. Pompei30, H. Rauer18;5;38, G. Ricker21, F. Rodler30, S. Seager21;31;32, L. M. Serrano4, A. M. S. Smith18, L. Spina33, J. Subjak34;24, P. Tenenbaum35, E.B. Ting23, A. Vanderburg39, R. Vanderspek21, V. Van Eylen36, S. Villanueva21, J. N. Winn17 Authors’ affiliations are shown at the end of the manuscript Accepted XXX. Received YYY; in original form ZZZ ABSTRACT We report the discovery of a planetary system orbiting TOI-763 (aka CD-39 7945), a V = 10:2, high proper motion G-type dwarf star that was photometrically monitored by the TESS space mission in Sector 10. We obtain and model the stellar spectrum and find an object slightly smaller than the Sun, and somewhat older, but with a similar metallicity. Two planet candidates were found in the light curve to be transiting the star.