Planets Beyond the Solar System
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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. -
History of Astrometry
5 Gaia web site: http://sci.esa.int/Gaia site: web Gaia 6 June 2009 June are emerging about the nature of our Galaxy. Galaxy. our of nature the about emerging are More detailed information can be found on the the on found be can information detailed More technologies developed by creative engineers. creative by developed technologies scientists all over the world, and important conclusions conclusions important and world, the over all scientists of the Universe combined with the most cutting-edge cutting-edge most the with combined Universe the of The results from Hipparcos are being analysed by by analysed being are Hipparcos from results The expression of a widespread curiosity about the nature nature the about curiosity widespread a of expression 118218 stars to a precision of around 1 milliarcsecond. milliarcsecond. 1 around of precision a to stars 118218 trying to answer for many centuries. It is the the is It centuries. many for answer to trying created with the positions, distances and motions of of motions and distances positions, the with created will bring light to questions that astronomers have been been have astronomers that questions to light bring will accuracies obtained from the ground. A catalogue was was catalogue A ground. the from obtained accuracies Gaia represents the dream of many generations as it it as generations many of dream the represents Gaia achieving an improvement of about 100 compared to to compared 100 about of improvement an achieving orbit, the Hipparcos satellite observed the whole sky, sky, whole the observed satellite Hipparcos the orbit, ear Y of them in the solar neighbourhood. -
Astrophysical Artefact in the Astrometric Detection of Exoplanets ?
Astrophysical artefact in the astrometric detection of exoplanets ? Jean Schneider LUTh – Paris Observatory Work in progress ● Dynamical and brightness astrometry ● Astrophysical sources of excess brightness – Simulations – Observations ● Conclusion 12 Oct 2011 1 Context Ultimate goal: the precise physical characterization of Earth-mass planets in the Habitable Zone (~ 1 AU) by direct spectro- polarimetric imaging It will also require a good knowledge of their mass. Two approaches (also used to find Earth-mass planets): – Radial Velocity measurements – Astrometry 12 Oct 2011 2 Context Radial Velocity and Astrometric mass measurements have both their limitations . Here we investigate a possible artefact of the astrometric approach for the Earth-mass regime at 1 AU. ==> not applicable to Gaia or PRIMA/ESPRI Very simple idea: can a blob in a disc mimic the astrometric signal of an Earth-mass planet at 1 AU? 12 Oct 2011 3 Dynamical and brightness astrometry Baryc. M M * C B I Ph I I << I 1 2 2 1 Photoc. a M a = C ● Dynamical astrometry B M* D I I M ● 2 a 2 C a Brightness (photometric) astrometry Ph= − B= − I1 D I1 M* D Question: can ph be > B ? 12 Oct 2011 4 Dynamical and brightness astrometry Baryc. M M * C B I Ph I I << I 1 2 2 1 Photoc. MC a −6 a ● = B ~ 3 x 10 for a 1 Earth-mass planet M* D D I a I a = 2 − ~ 2 -6 ● Ph B Can I /I be > 3x10 ? I1 D I1 D 2 1 12 Oct 2011 5 Dynamical and brightness astrometry Baryc. -
DOUBLE STARS INFORMATION CIRCULAR No. 202 (OCTOBER 2020)
INTERNATIONAL ASTRONOMICAL UNION COMMISSION G1 (BINARY AND MULTIPLE STAR SYSTEMS) DOUBLE STARS INFORMATION CIRCULAR No. 202 (OCTOBER 2020) NEW ORBITS ADS Name P T e Ω(2000) 2020 Author(s) α2000δ n a i ! Last ob. 2021 1762 A 207 1204y6 1937.27 0.816 31◦3 358◦9 000629 SCARDIA 02182+3920 0◦2989 000950 31◦1 193◦9 2020.771 359.2 0.635 et al. (*) 1477 WRH 39 Aa,Ab 29.59 1987.66 0.608 189.5 327.3 0.081 DOCOBO 02318+8916 12.1663 0.120 146.2 123.0 2014.4856 312.1 0.093 & CAMPO - COU 1688 AB 8.638 2003.841 0.198 49.2 247.6 0.121 DOCOBO 03321+4340 41.6763 0.139 35.5 268.2 2012.7023 308.0 0.092 & LING 3303 HU 1082 53.17 2023.24 0.746 108.9 221.1 0.151 DOCOBO 04349+3908 6.7707 0.362 48.9 216.3 2007.8019 240.7 0.132 & LING 3730 BU 1047 BC 34.38 2001.21 0.944 30.9 78.1 0.357 DOCOBO 05098+2802 10.4712 0.282 122.4 114.9 2007.8184 77.0 0.357 & CAMPO 11635 STF 2382 AB 2802.8 2051.49 0.953 149.6 344.3 2.169 DOCOBO 18443+3940 0.1284 14.237 102.2 258.8 2020.7470 344.0 2.148 & CAMPO 11635 STF 2383 CD 724.3 2223.9 0.353 26.5 74.3 2.399 DOCOBO 18443+3940 0.4970 2.920 126.1 73.8 2020.7470 73.9 2.402 & CAMPO 11635 CHR 77 Ca,Cb 15.75 2008.94 0.411 42.4 48.2 0.229 DOCOBO 18443+3940 22.8571 0.191 109.9 127.2 2005.5155 42.9 0.214 & CAMPO 13950 COU 1962 AB 20.414 1999.240 0.524 116.7 108.5 0.086 DOCOBO 20311+3333 17.6350 0.201 76.0 307.2 2008.5460 121.7 0.119 & CAMPO (*) SCARDIA, PRIEUR, PANSECCHI, LING, ARGYLE, ARISTIDI, ZANUTTA, ABE, BENDJOYA, RIVET, SUAREZ & VERNET 1 SARAH LEE LIPPINCOTT (1920-2019) Sarah Lee Lippincott was born in Philadelphia in 1920 and attended the University of Pennsylvania College for Women. -
Halometry from Astrometry
Prepared for submission to JCAP Halometry from Astrometry Ken Van Tilburg,a;b Anna-Maria Taki,a Neal Weinera;c aCenter for Cosmology and Particle Physics, Department of Physics, New York University, New York, NY 10003, USA bSchool of Natural Sciences, Institute for Advanced Study, Princeton, NJ 08540, USA cCenter for Computational Astrophysics, Flatiron Institute, New York, NY 10010, USA E-mail: [email protected], [email protected], [email protected] Abstract. Halometry—mapping out the spectrum, location, and kinematics of nonluminous structures inside the Galactic halo—can be realized via variable weak gravitational lensing of the apparent motions of stars and other luminous background sources. Modern astrometric surveys provide unprecedented positional precision along with a leap in the number of cat- aloged objects. Astrometry thus offers a new and sensitive probe of collapsed dark matter structures over a wide mass range, from one millionth to several million solar masses. It opens up a window into the spectrum of primordial curvature fluctuations with comoving wavenumbers between 5 Mpc−1 and 105 Mpc−1, scales hitherto poorly constrained. We out- line detection strategies based on three classes of observables—multi-blips, templates, and correlations—that take advantage of correlated effects in the motion of many background light sources that are produced through time-domain gravitational lensing. While existing techniques based on single-source observables such as outliers and mono-blips are best suited for point-like lens targets, our methods offer parametric improvements for extended lens tar- gets such as dark matter subhalos. Multi-blip lensing events may also unveil the existence, arXiv:1804.01991v1 [astro-ph.CO] 5 Apr 2018 location, and mass of planets in the outer reaches of the Solar System, where they would likely have escaped detection by direct imaging. -
September 2020 BRAS Newsletter
A Neowise Comet 2020, photo by Ralf Rohner of Skypointer Photography Monthly Meeting September 14th at 7:00 PM, via Jitsi (Monthly meetings are on 2nd Mondays at Highland Road Park Observatory, temporarily during quarantine at meet.jit.si/BRASMeets). GUEST SPEAKER: NASA Michoud Assembly Facility Director, Robert Champion What's In This Issue? President’s Message Secretary's Summary Business Meeting Minutes Outreach Report Asteroid and Comet News Light Pollution Committee Report Globe at Night Member’s Corner –My Quest For A Dark Place, by Chris Carlton Astro-Photos by BRAS Members Messages from the HRPO REMOTE DISCUSSION Solar Viewing Plus Night Mercurian Elongation Spooky Sensation Great Martian Opposition Observing Notes: Aquila – The Eagle Like this newsletter? See PAST ISSUES online back to 2009 Visit us on Facebook – Baton Rouge Astronomical Society Baton Rouge Astronomical Society Newsletter, Night Visions Page 2 of 27 September 2020 President’s Message Welcome to September. You may have noticed that this newsletter is showing up a little bit later than usual, and it’s for good reason: release of the newsletter will now happen after the monthly business meeting so that we can have a chance to keep everybody up to date on the latest information. Sometimes, this will mean the newsletter shows up a couple of days late. But, the upshot is that you’ll now be able to see what we discussed at the recent business meeting and have time to digest it before our general meeting in case you want to give some feedback. Now that we’re on the new format, business meetings (and the oft neglected Light Pollution Committee Meeting), are going to start being open to all members of the club again by simply joining up in the respective chat rooms the Wednesday before the first Monday of the month—which I encourage people to do, especially if you have some ideas you want to see the club put into action. -
New College News Release New College, Sarasota, Florida Furman C
/-·· NEW COLLEGE NEWS RELEASE NEW COLLEGE, SARASOTA, FLORIDA FURMAN C. ARTHUR - INFORMATION FOR RELEASE: Sunday, March 1, 1964 Sarasota--New College will have as its eighth lecturer in the New Perspectives in Science series Thursday at 8:00 p.m., Dutch born Dr. Peter van de Kamp, Director of the Sproul Observatory, swarthmore College. Dr. van de Kamp, the second astronomer in the series, approaches his field from a new viewpoint for the lecture at College Hall. He said that his talk will be about astronomy as a liberal art, "and by its very nature, peculiarly adapted to removing any artificial or imaginary bar- riers between the so-called sciences and the so-called liberal arts. Attendance at the lectures is by season registration although some single evening registrations are accepted. Born at Kampen in the Netherlands, Dr. van de Kamp was educated at the University of Utrecht where he studied astronomy, mathematics, and physics. Later, he obtained doctoral degrees at the University of California and the University of Groningen. Shortly after completing his education in the Netherlands, he came to this country to work at the McCormick Observatory at the University of Virginia and at the Lick Observatory at the University of California. (more) - 2 - Since 1937 he has been Director of the Sproul Observatory and Chairman of its Department of Astronomy. The Swarthmore observatory has one of the largest astronomical instruments of its kind. Dr. van de Kamp has taught or lectured a ·t many colleges in several countries. He is a former Fulbright scholar in France. During his education he was a member of Phi Beta Kappa and Sigma :· ~, honorary science research organization. -
Binocular Double Star Logbook
Astronomical League Binocular Double Star Club Logbook 1 Table of Contents Alpha Cassiopeiae 3 14 Canis Minoris Sh 251 (Oph) Psi 1 Piscium* F Hydrae Psi 1 & 2 Draconis* 37 Ceti Iota Cancri* 10 Σ2273 (Dra) Phi Cassiopeiae 27 Hydrae 40 & 41 Draconis* 93 (Rho) & 94 Piscium Tau 1 Hydrae 67 Ophiuchi 17 Chi Ceti 35 & 36 (Zeta) Leonis 39 Draconis 56 Andromedae 4 42 Leonis Minoris Epsilon 1 & 2 Lyrae* (U) 14 Arietis Σ1474 (Hya) Zeta 1 & 2 Lyrae* 59 Andromedae Alpha Ursae Majoris 11 Beta Lyrae* 15 Trianguli Delta Leonis Delta 1 & 2 Lyrae 33 Arietis 83 Leonis Theta Serpentis* 18 19 Tauri Tau Leonis 15 Aquilae 21 & 22 Tauri 5 93 Leonis OΣΣ178 (Aql) Eta Tauri 65 Ursae Majoris 28 Aquilae Phi Tauri 67 Ursae Majoris 12 6 (Alpha) & 8 Vul 62 Tauri 12 Comae Berenices Beta Cygni* Kappa 1 & 2 Tauri 17 Comae Berenices Epsilon Sagittae 19 Theta 1 & 2 Tauri 5 (Kappa) & 6 Draconis 54 Sagittarii 57 Persei 6 32 Camelopardalis* 16 Cygni 88 Tauri Σ1740 (Vir) 57 Aquilae Sigma 1 & 2 Tauri 79 (Zeta) & 80 Ursae Maj* 13 15 Sagittae Tau Tauri 70 Virginis Theta Sagittae 62 Eridani Iota Bootis* O1 (30 & 31) Cyg* 20 Beta Camelopardalis Σ1850 (Boo) 29 Cygni 11 & 12 Camelopardalis 7 Alpha Librae* Alpha 1 & 2 Capricorni* Delta Orionis* Delta Bootis* Beta 1 & 2 Capricorni* 42 & 45 Orionis Mu 1 & 2 Bootis* 14 75 Draconis Theta 2 Orionis* Omega 1 & 2 Scorpii Rho Capricorni Gamma Leporis* Kappa Herculis Omicron Capricorni 21 35 Camelopardalis ?? Nu Scorpii S 752 (Delphinus) 5 Lyncis 8 Nu 1 & 2 Coronae Borealis 48 Cygni Nu Geminorum Rho Ophiuchi 61 Cygni* 20 Geminorum 16 & 17 Draconis* 15 5 (Gamma) & 6 Equulei Zeta Geminorum 36 & 37 Herculis 79 Cygni h 3945 (CMa) Mu 1 & 2 Scorpii Mu Cygni 22 19 Lyncis* Zeta 1 & 2 Scorpii Epsilon Pegasi* Eta Canis Majoris 9 Σ133 (Her) Pi 1 & 2 Pegasi Δ 47 (CMa) 36 Ophiuchi* 33 Pegasi 64 & 65 Geminorum Nu 1 & 2 Draconis* 16 35 Pegasi Knt 4 (Pup) 53 Ophiuchi Delta Cephei* (U) The 28 stars with asterisks are also required for the regular AL Double Star Club. -
IAU Division C Working Group on Star Names 2019 Annual Report
IAU Division C Working Group on Star Names 2019 Annual Report Eric Mamajek (chair, USA) WG Members: Juan Antonio Belmote Avilés (Spain), Sze-leung Cheung (Thailand), Beatriz García (Argentina), Steven Gullberg (USA), Duane Hamacher (Australia), Susanne M. Hoffmann (Germany), Alejandro López (Argentina), Javier Mejuto (Honduras), Thierry Montmerle (France), Jay Pasachoff (USA), Ian Ridpath (UK), Clive Ruggles (UK), B.S. Shylaja (India), Robert van Gent (Netherlands), Hitoshi Yamaoka (Japan) WG Associates: Danielle Adams (USA), Yunli Shi (China), Doris Vickers (Austria) WGSN Website: https://www.iau.org/science/scientific_bodies/working_groups/280/ WGSN Email: [email protected] The Working Group on Star Names (WGSN) consists of an international group of astronomers with expertise in stellar astronomy, astronomical history, and cultural astronomy who research and catalog proper names for stars for use by the international astronomical community, and also to aid the recognition and preservation of intangible astronomical heritage. The Terms of Reference and membership for WG Star Names (WGSN) are provided at the IAU website: https://www.iau.org/science/scientific_bodies/working_groups/280/. WGSN was re-proposed to Division C and was approved in April 2019 as a functional WG whose scope extends beyond the normal 3-year cycle of IAU working groups. The WGSN was specifically called out on p. 22 of IAU Strategic Plan 2020-2030: “The IAU serves as the internationally recognised authority for assigning designations to celestial bodies and their surface features. To do so, the IAU has a number of Working Groups on various topics, most notably on the nomenclature of small bodies in the Solar System and planetary systems under Division F and on Star Names under Division C.” WGSN continues its long term activity of researching cultural astronomy literature for star names, and researching etymologies with the goal of adding this information to the WGSN’s online materials. -
The Search for Another Earth-Like Planet and Life Elsewhere Joshua Krissansen-Totton and David C
2 The Search for Another Earth-Like Planet and Life Elsewhere joshua krissansen-totton and david c. catling Introduction Is there life beyond Earth? Unlike most of the great cosmic questions pondered by anyone who has spent an evening of wonder beneath starry skies, this one seems accessible, perhaps even answerable. Other equally profound questions such as “Why does the universe exist?” and “How did life begin?” are perhaps more diffi- cult to address and must have complex explanations. But when one asks, “Is there life beyond Earth?” the answer is “Yes” or “No”. Yet despite the apparent simplic- ity, either conclusion would have profound implications. Few scientific discoveries have the power to reshape our sense of place inthe cosmos. The Copernican Revolution, the first such discovery, marked the birth of modern science. Suddenly, the Earth was no longer the center of the universe. This revelation heralded a series of findings that further diminished our perceived self- importance: the cosmic distance scale (Bessel, 1838), the true size of our galaxy (Shapley, 1918), the existence of other galaxies (Hubble, 1925), and finally, the large-scale structure and evolution of the cosmos. As Carl Sagan put it, “The Earth is a very small stage in a vast cosmic arena” (Sagan, 1994, p. 6). Darwin’s theory of evolution by natural selection was the next perspective- shifting discovery. By providing a scientific explanation for the complexity and diversity of life, the theory of evolution replaced the almost universal belief that each organism was designed by a creator. Every species, including our own, was a small twig in an immense and slowly changing tree of life, driven by variation and natural selection. -
Search for Brown-Dwarf Companions of Stars⋆⋆⋆
A&A 525, A95 (2011) Astronomy DOI: 10.1051/0004-6361/201015427 & c ESO 2010 Astrophysics Search for brown-dwarf companions of stars, J. Sahlmann1,2, D. Ségransan1,D.Queloz1,S.Udry1,N.C.Santos3,4, M. Marmier1,M.Mayor1, D. Naef1,F.Pepe1, and S. Zucker5 1 Observatoire de Genève, Université de Genève, 51 Chemin des Maillettes, 1290 Sauverny, Switzerland e-mail: [email protected] 2 European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching bei München, Germany 3 Centro de Astrofísica, Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal 4 Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, Portugal 5 Department of Geophysics and Planetary Sciences, Tel Aviv University, Tel Aviv 69978, Israel Received 19 July 2010 / Accepted 23 September 2010 ABSTRACT Context. The frequency of brown-dwarf companions in close orbit around Sun-like stars is low compared to the frequency of plane- tary and stellar companions. There is presently no comprehensive explanation of this lack of brown-dwarf companions. Aims. By combining the orbital solutions obtained from stellar radial-velocity curves and Hipparcos astrometric measurements, we attempt to determine the orbit inclinations and therefore the masses of the orbiting companions. By determining the masses of poten- tial brown-dwarf companions, we improve our knowledge of the companion mass-function. Methods. The radial-velocity solutions revealing potential brown-dwarf companions are obtained for stars from the CORALIE and HARPS planet-search surveys or from the literature. The best Keplerian fit to our radial-velocity measurements is found using the Levenberg-Marquardt method. -
Transiting Exoplanets from the Corot Space Mission. XI. Corot-8B: a Hot
Astronomy & Astrophysics manuscript no. corot-8b c ESO 2018 October 23, 2018 Transiting exoplanets from the CoRoT space mission XI. CoRoT-8b: a hot and dense sub-Saturn around a K1 dwarf? P. Borde´1, F. Bouchy2;3, M. Deleuil4, J. Cabrera5;6, L. Jorda4, C. Lovis7, S. Csizmadia5, S. Aigrain8, J. M. Almenara9;10, R. Alonso7, M. Auvergne11, A. Baglin11, P. Barge4, W. Benz12, A. S. Bonomo4, H. Bruntt11, L. Carone13, S. Carpano14, H. Deeg9;10, R. Dvorak15, A. Erikson5, S. Ferraz-Mello16, M. Fridlund14, D. Gandolfi14;17, J.-C. Gazzano4, M. Gillon18, E. Guenther17, T. Guillot19, P. Guterman4, A. Hatzes17, M. Havel19, G. Hebrard´ 2, H. Lammer20, A. Leger´ 1, M. Mayor7, T. Mazeh21, C. Moutou4, M. Patzold¨ 13, F. Pepe7, M. Ollivier1, D. Queloz7, H. Rauer5;22, D. Rouan11, B. Samuel1, A. Santerne4, J. Schneider6, B. Tingley9;10, S. Udry7, J. Weingrill20, and G. Wuchterl17 (Affiliations can be found after the references) Received ?; accepted ? ABSTRACT Aims. We report the discovery of CoRoT-8b, a dense small Saturn-class exoplanet that orbits a K1 dwarf in 6.2 days, and we derive its orbital parameters, mass, and radius. Methods. We analyzed two complementary data sets: the photometric transit curve of CoRoT-8b as measured by CoRoT and the radial velocity curve of CoRoT-8 as measured by the HARPS spectrometer??. Results. We find that CoRoT-8b is on a circular orbit with a semi-major axis of 0:063 ± 0:001 AU. It has a radius of 0:57 ± 0:02 RJ, a mass of −3 0:22 ± 0:03 MJ, and therefore a mean density of 1:6 ± 0:1 g cm .