Other Planetary Systems
Total Page：16
File Type：pdf, Size：1020Kb
Load more
Recommended publications
-
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. -
Jjmonl 1603.Pmd
alactic Observer GJohn J. McCarthy Observatory Volume 9, No. 3 March 2016 GRAIL - On the Trail of the Moon's Missing Mass GRAIL (Gravity Recovery and Interior Laboratory) was a NASA scientific mission in 2011/12 to map the surface of the moon and collect data on gravitational anomalies. The image here is an artist's impres- sion of the twin satellites (Ebb and Flow) orbiting in tandem above a gravitational image of the moon. See inside, page 4 for information on gravitational anomalies (mascons) or visit http://solarsystem. nasa.gov/grail. The John J. McCarthy Observatory Galactic Observer New Milford High School Editorial Committee 388 Danbury Road Managing Editor New Milford, CT 06776 Bill Cloutier Phone/Voice: (860) 210-4117 Production & Design Phone/Fax: (860) 354-1595 www.mccarthyobservatory.org Allan Ostergren Website Development JJMO Staff Marc Polansky It is through their efforts that the McCarthy Observatory Technical Support has established itself as a significant educational and Bob Lambert recreational resource within the western Connecticut Dr. Parker Moreland community. Steve Barone Jim Johnstone Colin Campbell Carly KleinStern Dennis Cartolano Bob Lambert Mike Chiarella Roger Moore Route Jeff Chodak Parker Moreland, PhD Bill Cloutier Allan Ostergren Cecilia Dietrich Marc Polansky Dirk Feather Joe Privitera Randy Fender Monty Robson Randy Finden Don Ross John Gebauer Gene Schilling Elaine Green Katie Shusdock Tina Hartzell Paul Woodell Tom Heydenburg Amy Ziffer In This Issue "OUT THE WINDOW ON YOUR LEFT" ............................... 4 SUNRISE AND SUNSET ...................................................... 13 MARE HUMBOLDTIANIUM AND THE NORTHEAST LIMB ......... 5 JUPITER AND ITS MOONS ................................................. 13 ONE YEAR IN SPACE ....................................................... 6 TRANSIT OF JUPITER'S RED SPOT .................................... -
Kein Folientitel
The Doppler Method, or the Radial Velocity Detection of Planets: II. Results Telescope Instrument Wavelength Reference 1-m MJUO Hercules Th-Ar / Iodine cell 1.2-m Euler Telescope CORALIE Th-Ar 1.8-m BOAO BOES Iodine Cell 1.88-m Okayama Obs, HIDES Iodine Cell 1.88-m OHP SOPHIE Th-Ar 2-m TLS Coude Echelle Iodine Cell 2.2m ESO/MPI La Silla FEROS Th-Ar 2.7m McDonald Obs. 2dcoude Iodine cell 3-m Lick Observatory Hamilton Echelle Iodine cell 3.8-m TNG SARG Iodine Cell 3.9-m AAT UCLES Iodine cell 3.6-m ESO La Silla HARPS Th-Ar 8.2-m Subaru Telescope HDS Iodine Cell 8.2-m VLT UVES Iodine cell 9-m Hobby-Eberly HRS Iodine cell 10-m Keck HiRes Iodine cell Campbell & Walker: The Pioneers of RV Planet Searches 1988: 1980-1992 searched for planets around 26 solar-type stars. Even though they found evidence for planets, they were not 100% convinced. If they had looked at 100 stars they certainly would have found convincing evidence for exoplanets. Campbell, Walker, & Yang 1988 „Probable third body variation of 25 m s–1, 2.7 year period, superposed on a large velocity gradient“ The first (?) extrasolar planet around a normal star: HD 114762 with M sin i = 11 MJ discovered by Latham et al. (1989) Filled circles are data taken at McDonald Observatory using the telluric lines at 6300 Ang. The mass was uncomfortably high (remember sin i effect) to regard it unambiguously as an extrasolar planet The Search For Extrasolar Planets At McDonald Observatory Bill Cochran & Artie Hatzes Hobby-Eberly 9 m Telescope Harlan J. -
2016 Publication Year 2021-04-23T14:32:39Z Acceptance in OA@INAF Age Consistency Between Exoplanet Hosts and Field Stars Title B
Publication Year 2016 Acceptance in OA@INAF 2021-04-23T14:32:39Z Title Age consistency between exoplanet hosts and field stars Authors Bonfanti, A.; Ortolani, S.; NASCIMBENI, VALERIO DOI 10.1051/0004-6361/201527297 Handle http://hdl.handle.net/20.500.12386/30887 Journal ASTRONOMY & ASTROPHYSICS Number 585 A&A 585, A5 (2016) Astronomy DOI: 10.1051/0004-6361/201527297 & c ESO 2015 Astrophysics Age consistency between exoplanet hosts and field stars A. Bonfanti1;2, S. Ortolani1;2, and V. Nascimbeni2 1 Dipartimento di Fisica e Astronomia, Università degli Studi di Padova, Vicolo dell’Osservatorio 3, 35122 Padova, Italy e-mail: [email protected] 2 Osservatorio Astronomico di Padova, INAF, Vicolo dell’Osservatorio 5, 35122 Padova, Italy Received 2 September 2015 / Accepted 3 November 2015 ABSTRACT Context. Transiting planets around stars are discovered mostly through photometric surveys. Unlike radial velocity surveys, photo- metric surveys do not tend to target slow rotators, inactive or metal-rich stars. Nevertheless, we suspect that observational biases could also impact transiting-planet hosts. Aims. This paper aims to evaluate how selection effects reflect on the evolutionary stage of both a limited sample of transiting-planet host stars (TPH) and a wider sample of planet-hosting stars detected through radial velocity analysis. Then, thanks to uniform deriva- tion of stellar ages, a homogeneous comparison between exoplanet hosts and field star age distributions is developed. Methods. Stellar parameters have been computed through our custom-developed isochrone placement algorithm, according to Padova evolutionary models. The notable aspects of our algorithm include the treatment of element diffusion, activity checks in terms of 0 log RHK and v sin i, and the evaluation of the stellar evolutionary speed in the Hertzsprung-Russel diagram in order to better constrain age. -
Exoplanet Detection Techniques
Exoplanet Detection Techniques Debra A. Fischer1, Andrew W. Howard2, Greg P. Laughlin3, Bruce Macintosh4, Suvrath Mahadevan5;6, Johannes Sahlmann7, Jennifer C. Yee8 We are still in the early days of exoplanet discovery. Astronomers are beginning to model the atmospheres and interiors of exoplanets and have developed a deeper understanding of processes of planet formation and evolution. However, we have yet to map out the full complexity of multi-planet architectures or to detect Earth analogues around nearby stars. Reaching these ambitious goals will require further improvements in instru- mentation and new analysis tools. In this chapter, we provide an overview of five observational techniques that are currently employed in the detection of exoplanets: optical and IR Doppler measurements, transit pho- tometry, direct imaging, microlensing, and astrometry. We provide a basic description of how each of these techniques works and discuss forefront developments that will result in new discoveries. We also highlight the observational limitations and synergies of each method and their connections to future space missions. Subject headings: 1. Introduction tary; in practice, they are not generally applied to the same sample of stars, so our detection of exoplanet architectures Humans have long wondered whether other solar sys- has been piecemeal. The explored parameter space of ex- tems exist around the billions of stars in our galaxy. In the oplanet systems is a patchwork quilt that still has several past two decades, we have progressed from a sample of one missing squares. to a collection of hundreds of exoplanetary systems. Instead of an orderly solar nebula model, we now realize that chaos 2. -
Determining the Mass of the Planetary Candidate HD 114762 B Using Gaia Flavien Kiefer
A&A 632, L9 (2019) Astronomy https://doi.org/10.1051/0004-6361/201936942 & c F. Kiefer 2019 Astrophysics LETTER TO THE EDITOR Determining the mass of the planetary candidate HD 114762 b using Gaia Flavien Kiefer Sorbonne Université, CNRS, UMR 7095, Institut d’Astrophysique de Paris, 98 bis bd Arago, 75014 Paris, France e-mail: [email protected] Received 16 October 2019 / Accepted 13 November 2019 ABSTRACT The first planetary candidate discovered by Latham et al. (1989, Nature, 339, 38) with radial velocities around a solar-like star other −1 than the Sun, HD 114762 b, was detected with a minimum mass of 11 MJ. The small v sin i ∼ 0 km s that is otherwise measured by spectral analysis indicated that this companion of a late-F subgiant star better corresponds to a massive brown dwarf (BD) or even a low-mass M-dwarf seen nearly face-on. To our knowledge, the nature of HD 114762 b is still undetermined. The astrometric noise measured for this system in the first data release, DR1, of the Gaia mission allows us to derive new constraints on the astrometric motion of HD 114762 and on the mass of its companion. We use the method GASTON, introduced in a preceding paper, which can simulate Gaia data and determine the distribution of inclinations that are compatible with the astrometric excess noise. With an +1:9 +31 inclination of 6.2−1:3 degree, the mass of the companion is constrained to Mb = 108−26 MJ. HD 114762 b thus indeed belongs to the M-dwarf domain, down to brown dwarfs, with Mb > 13:5 MJ at the 3σ level, and is not a planet. -
Propiedades F´Isicas De Estrellas Con Exoplanetas Y Anillos Circunestelares Por Carlos Saffe
Propiedades F´ısicas de Estrellas con Exoplanetas y Anillos Circunestelares por Carlos Saffe Presentado ante la Facultad de Matem´atica, Astronom´ıa y F´ısica como parte de los requerimientos para la obtenci´on del grado de Doctor en Astronom´ıa de la UNIVERSIDAD NACIONAL DE CORDOBA´ Marzo de 2008 c FaMAF - UNC 2008 Directora: Dr. Mercedes G´omez A Mariel, a Juancito y a Ramoncito. Resumen En este trabajo, estudiamos diferentes aspectos de las estrellas con exoplanetas (EH, \Exoplanet Host stars") y de las estrellas de tipo Vega, a fin de comparar ambos gru- pos y analizar la posible diferenciaci´on con respecto a otras estrellas de la vecindad solar. Inicialmente, compilamos la fotometr´ıa optica´ e infrarroja (IR) de un grupo de 61 estrellas con exoplanetas detectados por la t´ecnica Doppler, y construimos las dis- tribuciones espectrales de energ´ıa de estos objetos. Utilizamos varias cantidades para analizar la existencia de excesos IR de emisi´on, con respecto a los niveles fotosf´ericos normales. En particular, el criterio de Mannings & Barlow (1998) es verificado por 19-23 % (6-7 de 31) de las estrellas EH con clase de luminosidad V, y por 20 % (6 de 30) de las estrellas EH evolucionadas. Esta emisi´on se supone que es producida por la presencia de polvo en discos circunestelares. Sin embargo, en vista de la pobre resoluci´on espacial y problemas de confusi´on de IRAS, se requiere mayor resoluci´on y sensibilidad para confirmar la naturaleza circunestelar de las emisiones detectadas. Tambi´en comparamos las propiedades de polarizaci´on. -
Determining the True Mass of Radial-Velocity Exoplanets with Gaia 9 Planet Candidates in the Brown-Dwarf/Stellar Regime and 27 Confirmed Planets
Astronomy & Astrophysics manuscript no. exoplanet_mass_gaia c ESO 2020 September 30, 2020 Determining the true mass of radial-velocity exoplanets with Gaia 9 planet candidates in the brown-dwarf/stellar regime and 27 confirmed planets F. Kiefer1; 2, G. Hébrard1; 3, A. Lecavelier des Etangs1, E. Martioli1; 4, S. Dalal1, and A. Vidal-Madjar1 1 Institut d’Astrophysique de Paris, Sorbonne Université, CNRS, UMR 7095, 98 bis bd Arago, 75014 Paris, France 2 LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 place Jules Janssen, 92195 Meudon, France? 3 Observatoire de Haute-Provence, CNRS, Universiteé d’Aix-Marseille, 04870 Saint-Michel-l’Observatoire, France 4 Laboratório Nacional de Astrofísica, Rua Estados Unidos 154, 37504-364, Itajubá - MG, Brazil Submitted on 2020/08/20 ; Accepted for publication on 2020/09/24 ABSTRACT Mass is one of the most important parameters for determining the true nature of an astronomical object. Yet, many published exoplan- ets lack a measurement of their true mass, in particular those detected thanks to radial velocity (RV) variations of their host star. For those, only the minimum mass, or m sin i, is known, owing to the insensitivity of RVs to the inclination of the detected orbit compared to the plane-of-the-sky. The mass that is given in database is generally that of an assumed edge-on system (∼90◦), but many other inclinations are possible, even extreme values closer to 0◦ (face-on). In such case, the mass of the published object could be strongly underestimated by up to two orders of magnitude. -
Evidence for Enhanced Chromospheric Ca II H and K Emission in Stars with Close-In Extrasolar Planets
A&A 540, A82 (2012) Astronomy DOI: 10.1051/0004-6361/201118247 & c ESO 2012 Astrophysics Evidence for enhanced chromospheric Ca II H and K emission in stars with close-in extrasolar planets T. Krejcovᡠ1 and J. Budaj2 1 Department of Theoretical Physics and Astrophysics, Masaryk University, Kotlárskᡠ2, 61137 Brno, Czech Republic e-mail: [email protected] 2 Astronomical Institute, Slovak Academy of Sciences, 05960 Tatranská Lomnica, Slovak Republic e-mail: [email protected] Received 11 October 2011 / Accepted 13 February 2012 ABSTRACT Context. The planet-star interaction is manifested in many ways. It has been found that a close-in exoplanet causes small but mea- surable variability in the cores of a few lines in the spectra of several stars, which corresponds to the orbital period of the exoplanet. Stars with and without exoplanets may have different properties. Aims. The main goal of our study is to search for the influence that exoplanets might have on atmospheres of their host stars. Unlike the previous studies, we do not study changes in the spectrum of a host star or differences between stars with and without exoplanets. We aim to study a large number of stars with exoplanets and the current level of their chromospheric activity and to look for a possible correlation with the exoplanetary properties. Methods. To analyse the chromospheric activity of stars, we exploited our own and publicly available archival spectra, measured the equivalent widths of the cores of Ca II H and K lines, and used them to trace their activity. Subsequently, we searched for their dependence on the orbital parameters and the mass of the exoplanet. -
Solar System Analogues Among Exoplanetary Systems
Solar System analogues among exoplanetary systems Maria Lomaeva Lund Observatory Lund University ´´ 2016-EXA105 Degree project of 15 higher education credits June 2016 Supervisor: Piero Ranalli Lund Observatory Box 43 SE-221 00 Lund Sweden Populärvetenskaplig sammanfattning Människans intresse för rymden har alltid varit stort. Man har antagit att andra plan- etsystem, om de existerar, ser ut som vårt: med mindre stenplaneter i banor närmast stjärnan och gas- samt isjättar i de yttre banorna. Idag känner man till drygt 2 000 exoplaneter, d.v.s., planeter som kretsar kring andra stjärnor än solen. Man vet även att vissa av dem saknar motsvarighet i solsystemet, t. ex., heta jupitrar (gasjättar som har migrerat inåt och kretsar väldigt nära stjärnan) och superjordar (stenplaneter större än jorden). Därför blir frågan om hur unikt solsystemet är ännu mer intressant, vilket vi försöker ta reda på i det här projektet. Det finns olika sätt att detektera exoplaneter på men två av dem har gett flest resultat: transitmetoden och dopplerspektroskopin. Med transitmetoden mäter man minsknin- gen av en stjärnas ljus när en planet passerar framför den. Den metoden passar bäst för stora planeter med små omloppsbanor. Dopplerspektroskopin använder sig av Doppler effekten som innebär att ljuset utsänt från en stjärna verkar blåare respektive rödare när en stjärna förflyttar sig fram och tillbaka från observatören. Denna rörelse avslöjar att det finns en planet som kretsar kring stjärnan och påverkar den med sin gravita- tion. Dopplerspektroskopin är lämpligast för massiva planeter med små omloppsbanor. Under projektets gång har vi inte bara letat efter solsystemets motsvarigheter utan även studerat planetsystem som är annorlunda. -
Astronomy Dr
Astronomy Dr. Denise Meeks [email protected] http://denisemeeks.com/science/notebooks/notebook_astronomy.pdf Astronomy: Earth Astronomy: Equinoxes and Solstices equinox: when the plane average standard of Earth's equator passes density atmosphere through the center of the mass (kg) radius (km) (gm/cm3) (pascals) Sun, occurs around Mar. 24 20 and Sep. 23 5.97 x 10 6,378 5.514 101,325 solstice: when the Sun mean distance reaches its most northern from Sun perihelion aphelion or southern excursion (km = 1 AU) (km) (km) axial tilt relative to the celestial 1.496 x 108 1.471 x 108 1.521 x 108 23.450 equator; occurs around average escape Jun. 21 and Dec. 21 gravity orbital speed velocity orbital (Image source: 2 https://cbsboston.files.wordp (m/s ) (km/s) (km/s) eccentricity ress.com/2015/09/sky.jpg) 9.81 29.78 11.186 0.0167 Astronomy: Celestial Sphere Astronomy: Ecliptic celestial spere: an imaginary sphere of arbitrarily large radius, concentric with Earth; all objects in the observer's sky can be thought of as projected upon the inside surface (Image of the celestial sphere source: https://ww w.quora.co m/What-is- (Image source: the- https://en.wikipedia.org/wiki/Celestial_sphere; image source: Lunar and Planetary ecliptic) Institute) Astronomy: Milankovitch Cycles (1) Astronomy: Milankovitch Cycles (2) Milankovitch cycles: describes the collective effects of changes in the Earth's movements on climate; theory that variations in eccentricity, axial tilt, and precession of Earth's orbit strongly influenced climatic patterns eccentricity: -
June 2021 BRAS Newsletter
A JPL Image of surface of Mars, and JPL Ingenuity Helicioptor illustration. Monthly Meeting June 14th at 7:00 PM, in person at last!!! (Monthly meetings are on 2nd Mondays at Highland Road Park Observatory) You can also join this meeting via meet.jit.si/BRASMeet PRESENTATION: a demonstration on how to clean the optics of an SCT or refracting telescope. What's In This Issue? President’s Message Member Meeting Minutes Business Meeting Minutes Outreach Report Asteroid and Comet News Light Pollution Committee Report Globe at Night SubReddit and Discord BRAS Member Astrophotos Messages from the HRPO REMOTE DISCUSSION American Radio Relay League Field Day Observing Notes: Coma Berenices – Berenices Hair Like this newsletter? See PAST ISSUES online back to 2009 Visit us on Facebook – Baton Rouge Astronomical Society BRAS YouTube Channel Baton Rouge Astronomical Society Newsletter, Night Visions Page 2 of 23 June 2021 President’s Message Spring is just flying by it seems. Already June, galaxy season is peeking and the nebulous treasures closer to the Milky Way are starting to creep into the late evening sky. And as a final signal of Spring, we have a variety of life creeping up at the observatory on Highland Road (and not just the ample wildlife that’s been pushed out of the bayou by the rising flood waters, either). Astronomy Day was pretty big success (a much larger crowd than showed up last spring, at any rate) and making good on the ancient prophecy, we began having meetings at HRPO once again. Thanks again to Melanie for helping us score such a fantastic speaker for our homecoming, too.