Direct Detection of Exoplanets 717

Total Page:16

File Type:pdf, Size:1020Kb

Direct Detection of Exoplanets 717 Beuzit et al.: Direct Detection of Exoplanets 717 Direct Detection of Exoplanets J.-L. Beuzit Laboratoire d’Astrophysique de Grenoble D. Mouillet Observatoire Midi-Pyrénées B. R. Oppenheimer American Museum of Natural History J. D. Monnier University of Michigan, Ann Arbor Direct detection of exoplanets from the ground is now within reach of existing astronomical instruments. Indeed, a few planet candidates have already been imaged and analyzed and the capability to detect (through imaging or interferometry) young, hot, Jupiter-mass planets ex- ists. We present here an overview of what such detection methods can be expected to do in the near and far term. These methods will provide qualitatively new information about exoplanets, including spectroscopic data that will mature the study of exoplanets into a new field of com- parative exoplanetary science. Spectroscopic study of exoplanet atmospheres promises to reveal aspects of atmospheric physics and chemistry as well as internal structure. Astrometric meas- urements will complete orbital element determinations partially known from the radial velocity surveys. We discuss the impact of these techniques, on three different timescales, corresponding to the currently available instruments, the new “Planet Finder” systems under development for 8- to 10-m telescopes, foreseen to be in operation in 5–10 years, and the more ambitious but more distant projects at the horizon of 2020. 1. INTRODUCTION Almost all the currently known exoplanets have been de- tected by radial velocity measurements. Due to the unknown Since the discovery of a planet around a solar-type star inclination angle of the orbit, only a lower limit of the mass 10 years ago by Mayor and Queloz (1995), the study of exo- can actually be derived for each individual planet candidate. planets has developed into one of the primary research areas The statistical distribution of exoplanets can still be obtained in astronomy today. More than 170 exoplanets have been thanks to the large number of detections. These exoplanets found orbiting stars of spectral types F to M, with a signi- typically have masses similar to those of the giant, gaseous ficant fraction in multiplanet systems (see the chapter by planets in our own solar system. They are therefore gener- Udry et al. for a review). These exoplanets have been dis- ally referred to as extrasolar giant planets, or EGPs. Since covered using indirect detection methods, in which only the 2004, a few planets with minimum masses ranging between planet’s influence on the host star is observed. 6 and 25 M have been detected by radial velocity meas- Indirect detection techniques include radial velocity urements (Butler et al., 2004; Rivera et al., 2005; Bonfils measurements, which detect the movement of a star due to et al., 2005). Very recently, Beaulieu et al. (2006) have dis- a planet’s gravitational influence (see Marcy et al., 2003; covered a 5.5 M planet by gravitational lensing, assuming chapter by Udry et al.); photometric transit observations, a mass of 0.2 M for the host star, based on the peak of which detect the variation in the integrated stellar flux due the IMF at that mass. to a planetary companion passing through the line of sight These indirect methods have proven to be very success- to its host star (see chapter by Charbonneau et al.); as well ful in detecting exoplanets, but they only provide limited as astrometry, which also detects stellar motion (Sozzetti, information about the planets themselves. For example, 2005); and gravitational microlensing, which involves unre- radial velocity detections allow derivation of a planet’s or- peatable observations biased toward planets with short or- bital period and eccentricity as well as a lower limit to its bital periods (Mao and Paczynski, 1991; Gould and Loeb, mass due to the unknown inclination angle of the orbit. 1992). Photometric transit observations provide information about 717 718 Protostars and Planets V a planet’s radius and, with great effort, limited measure- ments of the composition of its upper atmosphere (Jha et al., 2000). In addition, large radial velocity surveys with sufficient precision only started about a decade ago. Thus, they are sensitive only to exoplanets with relatively small orbital periods, typically corresponding to objects at dis- tance smaller than a few AU from their parent stars. Cur- rently, these surveys are completely insensitive to planets at separations comparable to those of Jupiter and Saturn in our solar system. Finally, the accuracy of radial velocity measurements strongly biases the detections based on the Fig. 1. Examples of detection of planetary mass objects using type of the host stars toward old, quiet, and solar mass (G- current AO instruments. (Left) 2M1207 found by Chauvin et al. K) stars. Future extensive search for transiting planets will (2005a). (Right) GQ Lupi found by Neuhäuser et al. (2005). Both suffer similar biases regarding orbital periods and stellar objects are estimated by some researchers to have planetary mass. types. See section 2.1 for more detail. Direct detection and spectroscopy of the radiation from these exoplanets is necessary to determine their physical parameters, such as temperature, pressure, chemical compo- 2. SCIENCE sition, and atmospheric structure. These parameters are criti- cally needed to constrain theories of planet formation and 2.1. Direct Detections evolution. Furthermore, direct detection enables the study of planets in systems like our own. In these respects, direct Observations obtained in the past few years have reached detection is complementary to the indirect methods, espe- contrasts compatible with the detection of Jupiter-mass plan- cially to the radial velocity technique. ets in the most favorable case of very young ages (106 to a However, direct observation of exoplanets is still at the few 107 yr) when EGPs are still warm. Detection is typically edge of the current capabilities, able to reveal only the most possible outside a ~0.5" radius from the host star, corre- favorable cases of very young and massive planets at large sponding to a few tens of AU at the typical distances of distances from the central star (see section 2.1). The major young nearby stellar associations, i.e., closer than 100 pc challenge for direct study of the vast and seemingly diverse (Zuckerman and Song, 2004). population of exoplanets resides in the fact that most of the A few AO surveys of some of these associations con- planets are believed to be 106–1012× fainter than their host ducted in recent years (e.g., Chauvin et al., 2002; Neu- stars, at separations in the subarcsecond regime. This re- häuser et al., 2003; Brandeker et al., 2003; Beuzit et al., quires both high-contrast and spatial resolution. 2004; Masciadri et al., 2005) indeed resulted in the first Various instrumental approaches have been proposed for three direct detections of exoplanet candidates. These dis- the direct detection of exoplanets, either from the ground coveries include a companion around the brown dwarf or from space. In particular, several concepts of high-order 2MASSWJ 1207334-393254 (hereafter 2M1207), a mem- adaptive optics (AO) systems dedicated to groundbased ber of the young TW Hydrae Association, by Chauvin et large (and small) telescopes have been published during the al. (2005a); around the classical T Tauri star GQ Lup by past 10 years (Angel and Burrows, 1995; Dekany et al., Neuhäuser et al. (2005); and around AB Pic, a member of 2000; Mouillet et al., 2002; Macintosh et al., 2002; Oppen- the large Tucana-Horologium association, by Chauvin et al. heimer et al., 2003). Interferometric systems, using either a (2005b). Figure 1 illustrates the detection of two of these nulling or a differential phase approach, have also been de- planet candidates, 2M1207 B and GQ Lup. scribed (see section 4). Space missions have been proposed, The analyses of the proper motions, colors, and low- relying either on coronagraphic imaging [TPF-C observa- resolution spectra of these objects definitely confirm their tory (see chapter by Stapelfeldt et al.)] or on interferometry status as co-moving, very-low-mass, companions. An esti- [TPF-I and Darwin projects (e.g., Mennesson et al., 2005; mation of the actual mass of these companions requires the Kaltenegger and Fridlund, 2005, and references therein)]. determination of their luminosity and temperature through In this chapter, we present the scientific objectives of the theoretical models, such as the Tucson (Burrows et al., direct detection of exoplanets, concentrating on ground- 1997) and Lyon (Chabrier et al., 2000; Baraffe et al., 2002) based approaches (see chapter by Stapelfeldt et al. for space- models. These models are known to be uncertain at early based approaches). We discuss the principle, performance, ages, typically <100 m.y., and the derived mass estimates, and impact of the high-contrast imaging and interferometric and therefore whether these companions are brown dwarfs or techniques on three different timescales, corresponding to planets, should be considered with caution (see Neuhäuser, the currently available instruments, the new “Planet Finder” 2006). systems under development and foreseen to be in operation In any case, these observational results can now be di- in about five years, and the more ambitious projects on the rectly compared to theoretical models. Such detections at 2020 horizon. very large orbital separations (55 to 250 AU) also possibly Beuzit et al.: Direct Detection of Exoplanets 719 constrain the formation mechanisms of such planetary mass ing long-term monitoring campaigns commensurate with objects (see, for example, chapters by Lissauer et al., Duri- that of indirect methods (10–20 years). sen et al., Papaloizou et al., and Chabrier et al. for a dis- 4. Measurement of planet colors will constitute the first cussion of these mechanisms). direct tests of atmospheric models, and will provide infor- These first direct detections are very encouraging and mation on the presence of clouds in the planetary atmos- they clearly open a new window for exoplanet characteriza- phere, for instance.
Recommended publications
  • Lurking in the Shadows: Wide-Separation Gas Giants As Tracers of Planet Formation
    Lurking in the Shadows: Wide-Separation Gas Giants as Tracers of Planet Formation Thesis by Marta Levesque Bryan In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California 2018 Defended May 1, 2018 ii © 2018 Marta Levesque Bryan ORCID: [0000-0002-6076-5967] All rights reserved iii ACKNOWLEDGEMENTS First and foremost I would like to thank Heather Knutson, who I had the great privilege of working with as my thesis advisor. Her encouragement, guidance, and perspective helped me navigate many a challenging problem, and my conversations with her were a consistent source of positivity and learning throughout my time at Caltech. I leave graduate school a better scientist and person for having her as a role model. Heather fostered a wonderfully positive and supportive environment for her students, giving us the space to explore and grow - I could not have asked for a better advisor or research experience. I would also like to thank Konstantin Batygin for enthusiastic and illuminating discussions that always left me more excited to explore the result at hand. Thank you as well to Dimitri Mawet for providing both expertise and contagious optimism for some of my latest direct imaging endeavors. Thank you to the rest of my thesis committee, namely Geoff Blake, Evan Kirby, and Chuck Steidel for their support, helpful conversations, and insightful questions. I am grateful to have had the opportunity to collaborate with Brendan Bowler. His talk at Caltech my second year of graduate school introduced me to an unexpected population of massive wide-separation planetary-mass companions, and lead to a long-running collaboration from which several of my thesis projects were born.
    [Show full text]
  • Astronomy DOI: 10.1051/0004-6361/201423537 & C ESO 2014 Astrophysics
    A&A 565, A124 (2014) Astronomy DOI: 10.1051/0004-6361/201423537 & c ESO 2014 Astrophysics Carbon monoxide and water vapor in the atmosphere of the non-transiting exoplanet HD 179949 b? M. Brogi1, R. J. de Kok1;2, J. L. Birkby1, H. Schwarz1, and I. A. G. Snellen1 1 Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands e-mail: [email protected] 2 SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands Received 29 January 2014 / Accepted 5 April 2014 ABSTRACT Context. In recent years, ground-based high-resolution spectroscopy has become a powerful tool for investigating exoplanet atmo- spheres. It allows the robust identification of molecular species, and it can be applied to both transiting and non-transiting planets. Radial-velocity measurements of the star HD 179949 indicate the presence of a giant planet companion in a close-in orbit. The system is bright enough to be an ideal target for near-infrared, high-resolution spectroscopy. Aims. Here we present the analysis of spectra of the system at 2.3 µm, obtained at a resolution of R ∼ 100 000, during three nights of observations with CRIRES at the VLT. We targeted the system while the exoplanet was near superior conjunction, aiming to detect the planet’s thermal spectrum and the radial component of its orbital velocity. Methods. Unlike the telluric signal, the planet signal is subject to a changing Doppler shift during the observations. This is due to the changing radial component of the planet orbital velocity, which is on the order of 100–150 km s−1 for these hot Jupiters.
    [Show full text]
  • 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.
    [Show full text]
  • Applied Statistics
    ISSN 1932-6157 (print) ISSN 1941-7330 (online) THE ANNALS of APPLIED STATISTICS AN OFFICIAL JOURNAL OF THE INSTITUTE OF MATHEMATICAL STATISTICS Articles A Hermite–Gaussian based exoplanet radial velocity estimation method PARKER H. HOLZER,JESSI CISEWSKI-KEHE,DEBRA FISCHER AND LILY ZHAO 527 Hierarchical integrated spatial process modeling of monotone West Antarctic snow density curves. PHILIP A. WHITE,DURBAN G. KEELER AND SUMMER RUPPER 556 Estimating high-resolution Red Sea surface temperature hotspots, using a low-rank semiparametric spatial model. ARNAB HAZRA AND RAPHAËL HUSER 572 Learning excursion sets of vector-valued Gaussian random fields for autonomous ocean sampling..........TRYGVE OLAV FOSSUM,CÉDRIC TRAVELLETTI,JO EIDSVIK, DAV I D GINSBOURGER AND KANNA RAJAN 597 Aggregated pairwise classification of elastic planar shapes MIN HO CHO,SEBASTIAN KURTEK AND STEVEN N. MACEACHERN 619 A statistical pipeline for identifying physical features that differentiate classes of 3D shapes..............BRUCE WANG,TIMOTHY SUDIJONO,HENRY KIRVESLAHTI, TINGRAN GAO,DOUGLAS M. BOYER, SAYAN MUKHERJEE AND LORIN CRAWFORD 638 Simultaneous inference of periods and period-luminosity relations for Mira variable stars SHIYUAN HE,ZHENFENG LIN,WENLONG YUAN, LUCAS M. MACRI AND JIANHUA Z. HUANG 662 Scalable penalized spatiotemporal land-use regression for ground-level nitrogen dioxide KYLE P. M ESSIER AND MATTHIAS KATZFUSS 688 Probabilistic forecasting of the Arctic sea ice edge with contour modeling HANNAH M. DIRECTOR,ADRIAN E. RAFTERY AND CECILIA M. BITZ 711 Additive stacking for disaggregate electricity demand forecasting CHRISTIAN CAPEZZA,BIAGIO PALUMBO,YANNIG GOUDE, SIMON N. WOOD AND MATTEO FASIOLO 727 Causal mediation analysis for sparse and irregular longitudinal data . SHUXI ZENG, STACY ROSENBAUM,SUSAN C.
    [Show full text]
  • Arxiv:2105.11583V2 [Astro-Ph.EP] 2 Jul 2021 Keck-HIRES, APF-Levy, and Lick-Hamilton Spectrographs
    Draft version July 6, 2021 Typeset using LATEX twocolumn style in AASTeX63 The California Legacy Survey I. A Catalog of 178 Planets from Precision Radial Velocity Monitoring of 719 Nearby Stars over Three Decades Lee J. Rosenthal,1 Benjamin J. Fulton,1, 2 Lea A. Hirsch,3 Howard T. Isaacson,4 Andrew W. Howard,1 Cayla M. Dedrick,5, 6 Ilya A. Sherstyuk,1 Sarah C. Blunt,1, 7 Erik A. Petigura,8 Heather A. Knutson,9 Aida Behmard,9, 7 Ashley Chontos,10, 7 Justin R. Crepp,11 Ian J. M. Crossfield,12 Paul A. Dalba,13, 14 Debra A. Fischer,15 Gregory W. Henry,16 Stephen R. Kane,13 Molly Kosiarek,17, 7 Geoffrey W. Marcy,1, 7 Ryan A. Rubenzahl,1, 7 Lauren M. Weiss,10 and Jason T. Wright18, 19, 20 1Cahill Center for Astronomy & Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA 2IPAC-NASA Exoplanet Science Institute, Pasadena, CA 91125, USA 3Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305, USA 4Department of Astronomy, University of California Berkeley, Berkeley, CA 94720, USA 5Cahill Center for Astronomy & Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA 6Department of Astronomy & Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802, USA 7NSF Graduate Research Fellow 8Department of Physics & Astronomy, University of California Los Angeles, Los Angeles, CA 90095, USA 9Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA 10Institute for Astronomy, University of Hawai`i,
    [Show full text]
  • Jupiter Analogues and Planets of Acave Stars
    Jupiter analogues and planets of ac2ve stars. RV searches at MPIA Heidelberg Mar2n Kürster with Maren Mohler-Fischer (1) Jupiter analogues: The planet search programme at the ESO CES and HAPRS. IV. The search for Jupiter analogues around solar-type stars, Zechmeister, Kürster, Endl, Lo Curto, Hartman, Nilsson, Henning, Hatzes, Cochran, 2012, A&A accepted (2) A search for planets around ac2ve stars. Mohler-Fischer, Henning, Launhardt, Müller, Guenther (work in progress) (3) The first RV-confirmed planet from HAT-South: HATS-1b: The first transiGng plamet discovered by the HATSOUTH survey, Penev, Bakos, Bayliss, Jordán, Mohler-Fischer, Zhou, Suc, Rabus, Hartman, Mancini, Béky, Zsurby, Buchhave, Henning, Nikolov, Csák, Brahm, Espinosa, Conroy, Noyes, Sasselov, Schmidt, Wright, Tinney, Addison, Lásár, Papp, Sári 2012, in prep. La Silla Observatory, ESO, Chile Hot Planets and Cool Stars MPE Garching 13 November 2012 M. Kürster ad (2): A search for planets around ac2ve stars. Mohler-Fischer, Henning, Launhardt, Müller, Guenther (work in progress) G9V star, v sin i = 20.8 km/s, 57 spectra taken with FEROS @ MPG/ESO 2.2m La Silla Variaon due to stellar ac2vity / surface features Hot Planets and Cool Stars MPE Garching 13 November 2012 M. Kürster ad (3): HATS-1b See yesterday’s talk by Gaspar Bakos RV confirma2on: CORALIE: filled circles àFEROS: open triangles CYCLOPS: filled triangles Hot Planets and Cool Stars MPE Garching 13 November 2012 M. Kürster Two talks you cannot miss: Nadia Kostogryz ``A spectral differenLal characterizaon of low-mass companions´´ This aernoon, but unfortunately cancelled: Florian Rodler ``The return of the mummy: evidence for starlight reflected from the massive hot Jupiter τ Boo b´´ Hot Planets and Cool Stars MPE Garching 13 November 2012 M.
    [Show full text]
  • Introduction
    Introduction ”They say the sky is the limit, but to me, it is only the beginning. I look to the stars, and I count them, imagining every one of them as the centre of a solar system, even more wondrous than our own. We now know they are out there. Planets. Millions of them - just waiting to be discovered. What are they like, these distant spinning worlds? How did they come to be? And finally - before I close my eyes and go to sleep, one question lingers. Like the echo of a whisper : Is anyone out there...” The study of exoplanets is a quest to understand our place in the universe. How unique is the solar system? How extraordinary is the Earth? Is life on Earth an unfathomable coincidence, or is the galaxy teeming with life? Only 25 years ago the first extrasolar planets were discovered, two of them, orbiting the millisecond pulsar PSR1257+12 (Wolszczan and Frail, 1992), and this was followed three years later by the discovery of the first exoplanet orbiting a solar-type star (51 Pegasi, Mayor and Queloz, 1995). In the subsequent years, multiple techniques were developed to find and study these new worlds. Each detection method has its own advantages, limitations and biases, and they have complimented each other to form the picture of exoplanets that we have today: The galaxy is brimming with planetary systems, and the exoplanets are more diverse, than we could ever have imagined. The diversity of planets presents a challenge to the theories of formation designed to match the solar system, and any modern theories must strive to explain the full observed range of architectures of planetary systems.
    [Show full text]
  • Exoplanet.Eu Catalog Page 1 # Name Mass Star Name
    exoplanet.eu_catalog # name mass star_name star_distance star_mass OGLE-2016-BLG-1469L b 13.6 OGLE-2016-BLG-1469L 4500.0 0.048 11 Com b 19.4 11 Com 110.6 2.7 11 Oph b 21 11 Oph 145.0 0.0162 11 UMi b 10.5 11 UMi 119.5 1.8 14 And b 5.33 14 And 76.4 2.2 14 Her b 4.64 14 Her 18.1 0.9 16 Cyg B b 1.68 16 Cyg B 21.4 1.01 18 Del b 10.3 18 Del 73.1 2.3 1RXS 1609 b 14 1RXS1609 145.0 0.73 1SWASP J1407 b 20 1SWASP J1407 133.0 0.9 24 Sex b 1.99 24 Sex 74.8 1.54 24 Sex c 0.86 24 Sex 74.8 1.54 2M 0103-55 (AB) b 13 2M 0103-55 (AB) 47.2 0.4 2M 0122-24 b 20 2M 0122-24 36.0 0.4 2M 0219-39 b 13.9 2M 0219-39 39.4 0.11 2M 0441+23 b 7.5 2M 0441+23 140.0 0.02 2M 0746+20 b 30 2M 0746+20 12.2 0.12 2M 1207-39 24 2M 1207-39 52.4 0.025 2M 1207-39 b 4 2M 1207-39 52.4 0.025 2M 1938+46 b 1.9 2M 1938+46 0.6 2M 2140+16 b 20 2M 2140+16 25.0 0.08 2M 2206-20 b 30 2M 2206-20 26.7 0.13 2M 2236+4751 b 12.5 2M 2236+4751 63.0 0.6 2M J2126-81 b 13.3 TYC 9486-927-1 24.8 0.4 2MASS J11193254 AB 3.7 2MASS J11193254 AB 2MASS J1450-7841 A 40 2MASS J1450-7841 A 75.0 0.04 2MASS J1450-7841 B 40 2MASS J1450-7841 B 75.0 0.04 2MASS J2250+2325 b 30 2MASS J2250+2325 41.5 30 Ari B b 9.88 30 Ari B 39.4 1.22 38 Vir b 4.51 38 Vir 1.18 4 Uma b 7.1 4 Uma 78.5 1.234 42 Dra b 3.88 42 Dra 97.3 0.98 47 Uma b 2.53 47 Uma 14.0 1.03 47 Uma c 0.54 47 Uma 14.0 1.03 47 Uma d 1.64 47 Uma 14.0 1.03 51 Eri b 9.1 51 Eri 29.4 1.75 51 Peg b 0.47 51 Peg 14.7 1.11 55 Cnc b 0.84 55 Cnc 12.3 0.905 55 Cnc c 0.1784 55 Cnc 12.3 0.905 55 Cnc d 3.86 55 Cnc 12.3 0.905 55 Cnc e 0.02547 55 Cnc 12.3 0.905 55 Cnc f 0.1479 55
    [Show full text]
  • Arxiv:1501.00633V1 [Astro-Ph.EP] 4 Jan 2015 Teria (Han Et Al
    Draft version September 24, 2018 Preprint typeset using LATEX style emulateapj v. 5/2/11 THE CALIFORNIA PLANET SURVEY IV: A PLANET ORBITING THE GIANT STAR HD 145934 AND UPDATES TO SEVEN SYSTEMS WITH LONG-PERIOD PLANETS * Y. Katherina Feng1,4, Jason T. Wright1, Benjamin Nelson1, Sharon X. Wang1, Eric B. Ford1, Geoffrey W. Marcy2, Howard Isaacson2, and Andrew W. Howard3 (Received 2014 August 11; Accepted 2014 November 26) Draft version September 24, 2018 ABSTRACT We present an update to seven stars with long-period planets or planetary candidates using new and archival radial velocities from Keck-HIRES and literature velocities from other telescopes. Our updated analysis better constrains orbital parameters for these planets, four of which are known multi- planet systems. HD 24040 b and HD 183263 c are super-Jupiters with circular orbits and periods longer than 8 yr. We present a previously unseen linear trend in the residuals of HD 66428 indicative on an additional planetary companion. We confirm that GJ 849 is a multi-planet system and find a good orbital solution for the c component: it is a 1MJup planet in a 15 yr orbit (the longest known for a planet orbiting an M dwarf). We update the HD 74156 double-planet system. We also announce the detection of HD 145934 b, a 2MJup planet in a 7.5 yr orbit around a giant star. Two of our stars, HD 187123 and HD 217107, at present host the only known examples of systems comprising a hot Jupiter and a planet with a well constrained period > 5 yr, and with no evidence of giant planets in between.
    [Show full text]
  • Laporan Tahunan Persatuan Astronomi Negara Brunei Darussalam
    ﻻڤورن تاهونن Laporan Tahunan 2019 - 2020 Persatuan Astronomi Negara Brunei Darussalam Disediakan oleh Setiausaha Agung PABD 1 Kandungan • Pengenalan • Pindaan Pertama Perlembagaan PABD • Penaung & Penasihat PABD 2019/2020 • AJK Eksekutif PABD 2019/2020 • Pindaan Pertama Perlembagaan • Keahlian PABD • Kegiatan PABD www.bruneiastronomy.org • Jaringan Rakan Strategik PABD Fb.com/bruneiastronomy • Fenomena Astronomi 2021 www.bruneiastronomy.org/whatsapp • Laporan Khas: NameExoWorlds Brunei @bruneiastronomy • Laporan Khas: Telescope For All 2020 t.me/bruneiastronomy 2 Pengenalan PABD Agensi bukan Kerajaan yang unggul dalam bidang Astronomi di Negara Brunei Darussalam Persatuan Astronomi Negara Brunei Darussalam (PABD) merupakan persatuan bebas dan persatuan bukan Kerajaan yang didedikasi kepada masyarakat dan bidang sains astronomi. Ia adalah satu-satunya agensi bukan Kerajaan yang berkaitan dengan bidang astronomi di Negara Brunei Darussalam. PABD telah didaftarkan secara rasmi kepada Pendaftar Pertubuhan, Polis Di Raja Brunei, pada 06 Januari 2003 bersamaan dengan 03 Zulkaedah 1423 H. Peraturan-peraturan dan keterangan PABD telah termaktub di dalam Perlembagaan Persatuan Astronomi Negara Brunei Darussalam oleh ahli-ahli sementara PABD pada tahun 2002. Persatuan ini mempunyai Penaung, iaitu Ketua Hakim Syarie, Jabatan Kehakiman Negara, dan tiga orang ahli Penasihat yang terdiri daripada Hakim Mahkamah Tinggi Syariah Negara Brunei Darussalam, Juruukur Agung dan Naib Canselor Universiti Brunei Darussalam (UBD). Penambahan seorang penasihat,
    [Show full text]
  • Tidal Evolution of Close-In Extra-Solar Planets
    Tidal Evolution of Close-in Extra-Solar Planets by Brian Jackson, Richard Greenberg, and Rory Barnes Lunar and Planetary Laboratory University of Arizona 1629 E University Blvd, Tucson AZ 85721-0092 Accepted by Astrophysical Journal 2007 January 2 Revised: 2007 December 31 Running Title: Tidal Evolution - 1 - Abstract The distribution of eccentricities e of extra-solar planets with semi-major axes a > 0.2 AU is very uniform, and values for e are relatively large, averaging 0.3 and broadly distributed up to near 1. For a < 0.2 AU, eccentricities are much smaller (most e < 0.2), a characteristic widely attributed to damping by tides after the planets formed and the protoplanetary gas disk dissipated. Most previous estimates of the tidal damping considered the tides raised on the planets, but ignored the tides raised on the stars. Most also assumed specific values for the planets’ poorly constrained tidal dissipation parameter Qp. Perhaps most important, in many studies, the strongly coupled evolution between e and a was ignored. We have now integrated the coupled tidal evolution equations for e and a over the estimated age of each planet, and confirmed that the distribution of initial e values of close-in planets matches that of the general population for reasonable Q values, with the best fits for stellar and planetary Q being ~10 5.5 and ~10 6.5 , respectively. The accompanying evolution of a values shows most close-in planets had significantly larger a at the start of tidal migration. The earlier gas disk migration did not bring all planets to their current orbits.
    [Show full text]
  • 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.
    [Show full text]