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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. -
Today in Astronomy 106: Exoplanets
Today in Astronomy 106: exoplanets The successful search for extrasolar planets Prospects for determining the fraction of stars with planets, and the number of habitable planets per planetary system (fp and ne). T. Pyle, SSC/JPL/Caltech/NASA. 26 May 2011 Astronomy 106, Summer 2011 1 Observing exoplanets Stars are vastly brighter and more massive than planets, and most stars are far enough away that the planets are lost in the glare. So astronomers have had to be more clever and employ the motion of the orbiting planet. The methods they use (exoplanets detected thereby): Astrometry (0): tiny wobble in star’s motion across the sky. Radial velocity (399): tiny wobble in star’s motion along the line of sight by Doppler shift. Timing (9): tiny delay or advance in arrival of pulses from regularly-pulsating stars. Gravitational microlensing (10): brightening of very distant star as it passes behind a planet. 26 May 2011 Astronomy 106, Summer 2011 2 Observing exoplanets (continued) Transits (69): periodic eclipsing of star by planet, or vice versa. Very small effect, about like that of a bug flying in front of the headlight of a car 10 miles away. Imaging (11 but 6 are most likely to be faint stars): taking a picture of the planet, usually by blotting out the star. Of these by far the most useful so far has been the combination of radial-velocity and transit detection. Astrometry and gravitational microlensing of sufficient precision to detect lots of planets would need dedicated, specialized observatories in space. Imaging lots of planets will require 30-meter-diameter telescopes for visible and infrared wavelengths. -
Ghost Imaging of Space Objects
Ghost Imaging of Space Objects Dmitry V. Strekalov, Baris I. Erkmen, Igor Kulikov, and Nan Yu Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109-8099 USA NIAC Final Report September 2014 Contents I. The proposed research 1 A. Origins and motivation of this research 1 B. Proposed approach in a nutshell 3 C. Proposed approach in the context of modern astronomy 7 D. Perceived benefits and perspectives 12 II. Phase I goals and accomplishments 18 A. Introducing the theoretical model 19 B. A Gaussian absorber 28 C. Unbalanced arms configuration 32 D. Phase I summary 34 III. Phase II goals and accomplishments 37 A. Advanced theoretical analysis 38 B. On observability of a shadow gradient 47 C. Signal-to-noise ratio 49 D. From detection to imaging 59 E. Experimental demonstration 72 F. On observation of phase objects 86 IV. Dissemination and outreach 90 V. Conclusion 92 References 95 1 I. THE PROPOSED RESEARCH The NIAC Ghost Imaging of Space Objects research program has been carried out at the Jet Propulsion Laboratory, Caltech. The program consisted of Phase I (October 2011 to September 2012) and Phase II (October 2012 to September 2014). The research team consisted of Drs. Dmitry Strekalov (PI), Baris Erkmen, Igor Kulikov and Nan Yu. The team members acknowledge stimulating discussions with Drs. Leonidas Moustakas, Andrew Shapiro-Scharlotta, Victor Vilnrotter, Michael Werner and Paul Goldsmith of JPL; Maria Chekhova and Timur Iskhakov of Max Plank Institute for Physics of Light, Erlangen; Paul Nu˜nez of Coll`ege de France & Observatoire de la Cˆote d’Azur; and technical support from Victor White and Pierre Echternach of JPL. -
AMD-Stability and the Classification of Planetary Systems
A&A 605, A72 (2017) DOI: 10.1051/0004-6361/201630022 Astronomy c ESO 2017 Astrophysics& AMD-stability and the classification of planetary systems? J. Laskar and A. C. Petit ASD/IMCCE, CNRS-UMR 8028, Observatoire de Paris, PSL, UPMC, 77 Avenue Denfert-Rochereau, 75014 Paris, France e-mail: [email protected] Received 7 November 2016 / Accepted 23 January 2017 ABSTRACT We present here in full detail the evolution of the angular momentum deficit (AMD) during collisions as it was described in Laskar (2000, Phys. Rev. Lett., 84, 3240). Since then, the AMD has been revealed to be a key parameter for the understanding of the outcome of planetary formation models. We define here the AMD-stability criterion that can be easily verified on a newly discovered planetary system. We show how AMD-stability can be used to establish a classification of the multiplanet systems in order to exhibit the planetary systems that are long-term stable because they are AMD-stable, and those that are AMD-unstable which then require some additional dynamical studies to conclude on their stability. The AMD-stability classification is applied to the 131 multiplanet systems from The Extrasolar Planet Encyclopaedia database for which the orbital elements are sufficiently well known. Key words. chaos – celestial mechanics – planets and satellites: dynamical evolution and stability – planets and satellites: formation – planets and satellites: general 1. Introduction motion resonances (MMR, Wisdom 1980; Deck et al. 2013; Ramos et al. 2015) could justify the Hill-type criteria, but the The increasing number of planetary systems has made it nec- results on the overlap of the MMR island are valid only for close essary to search for a possible classification of these planetary orbits and for short-term stability. -
1949 Celebrating 65 Years of Bringing Astronomy to North Texas 2014
1949 Celebrating 65 Years of Bringing Astronomy to North Texas 2014 Contact information: Inside this issue: Info Officer (General Info)– [email protected]@fortworthastro.com Website Administrator – [email protected] Postal Address: Page Fort Worth Astronomical Society July Club Calendar 3 3812 Fenton Avenue Fort Worth, TX 76133 Celestial Events 4 Web Site: http://www.fortworthastro.org Facebook: http://tinyurl.com/3eutb22 Sky Chart 5 Twitter: http://twitter.com/ftwastro Yahoo! eGroup (members only): http://tinyurl.com/7qu5vkn Moon Phase Calendar 6 Officers (2014-2015): Mecury/Venus Data Sheet 7 President – Bruce Cowles, [email protected] Vice President – Russ Boatwright, [email protected] Young Astronomer News 8 Sec/Tres – Michelle Theisen, [email protected] Board Members: Cloudy Night Library 9 2014-2016 The Astrolabe 10 Mike Langohr Tree Oppermann AL Obs Club of the Month 14 2013-2015 Bill Nichols Constellation of the Month 15 Jim Craft Constellation Mythology 19 Cover Photo This is an HaLRGB image of M8 & Prior Club Meeting Minutes 23 M20, composed entirely from a T3i General Club Information 24 stack of one shot color. Collected the data over a period of two nights. That’s A Fact 24 Taken by FWAS member Jerry Keith November’s Full Moon 24 Observing Site Reminders: Be careful with fire, mind all local burn bans! FWAS Foto Files 25 Dark Site Usage Requirements (ALL MEMBERS): Maintain Dark-Sky Etiquettehttp://tinyurl.com/75hjajy ( ) Turn out your headlights at the gate! Sign -
The Mcdonald Observatory Planet Search: New Long-Period Giant
The McDonald Observatory Planet Search: New Long-Period Giant Planets, and Two Interacting Jupiters in the HD 155358 System Paul Robertson1, Michael Endl1, William D. Cochran1, Phillip J. MacQueen1, Robert A. Wittenmyer2, J. Horner2, Erik J. Brugamyer1, Attila E. Simon3,4, Stuart I. Barnes1, and Caroline Caldwell1 1Department of Astronomy and McDonald Observatory, University of Texas at Austin, Austin, TX 78712, USA; [email protected] 2Department of Astrophysics and Optics, School of Physics, University of New South Wales, Sydney, NSW 2052, Australia 3Konkoly Observatory of the Hungarian Academy of Sciences, PO. Box 67, H-1525 Budapest, Hungary 4Department of Experimental Physics and Astronomical Observatory, University of Szeged, 6720 Szeged, Hungary ABSTRACT We present high-precision radial velocity (RV) observations of four solar-type (F7- G5) stars – HD 79498, HD 155358, HD 197037, and HD 220773 – taken as part of the McDonald Observatory Planet Search Program. For each of these stars, we see evidence of Keplerian motion caused by the presence of one or more gas giant plan- ets in long-period orbits. We derive orbital parameters for each system, and note the properties (composition, activity, etc.) of the host stars. While we have previously announced the two-gas-giant HD 155358 system, we now report a shorter period for planet c. This new period is consistent with the planets being trapped in mutual 2:1 mean-motion resonance. We therefore perform an in-depth stability analysis, placing additional constraints on the orbital parameters of the planets. These results demon- strate the excellent long-term RV stability of the spectrometers on both the Harlan J. -
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. -
July 2014 BRAS Newsletter
July, 2014 Next Meeting July 19th, 11:00AM at LIGO The LIGO facility in Livingston Parish, LA What's In This Issue? President's Message Secretary's Summary of June Meeting Astroshort- Not-So-Rare Earths Message from the HRPO Globe At Night EBR Parish Library Children's Reading Program Recent BRAS Forum Entries Observing Notes from John Nagle President's Message WE WILL NOT MEET ON THE SECOND MONDAY NIGHT, AS WE USUALLY DO. Our next meeting will be Saturday, July 19, 2014, 11 AM – 4 PM at LIGO, Livingston. It will be a picnic/star-b-cue and enjoy each other’s company. We will meet under the pavilion by the pond at 11 AM to begin the picnic. BRAS will provide the main course. You can bring a small dish if you wish. At 1 PM, we can join the public for LIGO’s regular Saturday Science day activities. That includes the museum, hands on experiments, a video about LIGO “Einstein’s Messengers”, and a tour of the facility. One new thing we would like to do is set a table aside for anyone who has astronomical equipment they want to sell – telescopes, mounts, accessories, binoculars, cameras, books, etc. The idea is to have an impromptu garage sale (or swap meet). Bring what you have and let’s see if we can move it. LIGO is only open during the day, so the only stargazing we will be able to do will be solar. However, we will demonstrate the 35mm Lundt solar scope BRAS is raffling and sell tickets for the raffle. -
Paul Robertson, Ph.D
Paul Robertson, Ph.D. Assistant Professor Department of Physics & Astronomy Email: [email protected] The University of California, Irvine Phone: (949) 824-6660 4129 Frederick Reines Hall Web: http://faculty.sites.uci.edu/robertson/ Irvine, CA 92697 EDUCATION Doctor in Astrophysics, 2013 The University of Texas, Austin, TX Dissertation: “Discovering New Solar Systems: Jupiter Analogs and the Quest to Find Another Earth” Master of Arts in Astrophysics, 2010 The University of Texas, Austin, TX Thesis: “The Hobby-Eberly Telescope M dwarf Planet Search Program: New Observations and Results” Bachelor of Arts in Physics and Mathematics, 2008 The University of North Carolina, Chapel Hill, NC PROFESSIONAL APPOINTMENTS Assistant Professor, UC Irvine 2018-present NASA Sagan Fellow, Penn State University 2015-2017 Postdoctoral Fellow, Penn State University 2013-2015 AWARDS University of New South Wales Science Visiting Fellowship, 2016 Carl Sagan Fellowship, NASA, 2015 Graduate Continuing Fellowship, University of Texas, 2012-2013 Frank N. Edmonds Jr. Memorial Fellowship in Astronomy, The University of Texas, 2011-2012 Graduate with Distinction, The University of North Carolina, 2008 FIRST-AUTHORED PEER REVIEWED PUBLICATIONS Robertson, P., Anderson, T., Stefansson, G. et al. 2019, “Ultra-Stable Environment Control for the NEID Spectrometer: Design and Performance Demonstration.” Journal of Astronomical Telescopes, Instruments, and Systems, accepted. arXiv:1902.07729. Robertson, P. 2018. “Aliasing in the Radial Velocities of YZ Ceti: An Ultra-short Period for YZ Ceti c?” The Astrophysical Journal Letters, Vol. 864, p. 28. Robertson, P., Bender, C., Mahadevan, S., Roy, A., & Ramsey, L. W. 2016. “Proxima Centauri as a Benchmark for Stellar Activity Indicators in the Near Infrared.” The Astrophysical Journal, Vol. -
Survival of Exomoons Around Exoplanets 2
Survival of exomoons around exoplanets V. Dobos1,2,3, S. Charnoz4,A.Pal´ 2, A. Roque-Bernard4 and Gy. M. Szabo´ 3,5 1 Kapteyn Astronomical Institute, University of Groningen, 9747 AD, Landleven 12, Groningen, The Netherlands 2 Konkoly Thege Mikl´os Astronomical Institute, Research Centre for Astronomy and Earth Sciences, E¨otv¨os Lor´and Research Network (ELKH), 1121, Konkoly Thege Mikl´os ´ut 15-17, Budapest, Hungary 3 MTA-ELTE Exoplanet Research Group, 9700, Szent Imre h. u. 112, Szombathely, Hungary 4 Universit´ede Paris, Institut de Physique du Globe de Paris, CNRS, F-75005 Paris, France 5 ELTE E¨otv¨os Lor´and University, Gothard Astrophysical Observatory, Szombathely, Szent Imre h. u. 112, Hungary E-mail: [email protected] January 2020 Abstract. Despite numerous attempts, no exomoon has firmly been confirmed to date. New missions like CHEOPS aim to characterize previously detected exoplanets, and potentially to discover exomoons. In order to optimize search strategies, we need to determine those planets which are the most likely to host moons. We investigate the tidal evolution of hypothetical moon orbits in systems consisting of a star, one planet and one test moon. We study a few specific cases with ten billion years integration time where the evolution of moon orbits follows one of these three scenarios: (1) “locking”, in which the moon has a stable orbit on a long time scale (& 109 years); (2) “escape scenario” where the moon leaves the planet’s gravitational domain; and (3) “disruption scenario”, in which the moon migrates inwards until it reaches the Roche lobe and becomes disrupted by strong tidal forces. -
The 3D Secular Dynamics of Radial-Velocity-Detected Planetary Systems Mara Volpi, Arnaud Roisin, and Anne-Sophie Libert
A&A 626, A74 (2019) Astronomy https://doi.org/10.1051/0004-6361/201834896 & c ESO 2019 Astrophysics The 3D secular dynamics of radial-velocity-detected planetary systems Mara Volpi, Arnaud Roisin, and Anne-Sophie Libert NaXys, Department of Mathematics, University of Namur, Rempart de la Vierge 8, 5000 Namur, Belgium e-mail: [email protected] Received 17 December 2018 / Accepted 26 April 2019 ABSTRACT Aims. To date, more than 600 multi-planetary systems have been discovered. Due to the limitations of the detection methods, our knowledge of the systems is usually far from complete. In particular, for planetary systems discovered with the radial velocity (RV) technique, the inclinations of the orbital planes, and thus the mutual inclinations and planetary masses, are unknown. Our work aims to constrain the spatial configuration of several RV-detected extrasolar systems that are not in a mean-motion resonance. Methods. Through an analytical study based on a first-order secular Hamiltonian expansion and numerical explorations performed with a chaos detector, we identified ranges of values for the orbital inclinations and the mutual inclinations, which ensure the long-term stability of the system. Our results were validated by comparison with n-body simulations, showing the accuracy of our analytical approach up to high mutual inclinations (∼70◦−80◦). Results. We find that, given the current estimations for the parameters of the selected systems, long-term regular evolution of the spatial configurations is observed, for all the systems, (i) at low mutual inclinations (typically less than 35◦) and (ii) at higher mutual inclinations, preferentially if the system is in a Lidov-Kozai resonance. -
Predictions of Planets for 586 Exosystems and a Method for Predicting Planets in Multi-Planetary Exosystems Valeri Beck
Predictions of planets for 586 exosystems and a method for predicting planets in multi-planetary exosystems Valeri Beck To cite this version: Valeri Beck. Predictions of planets for 586 exosystems and a method for predicting planets in multi- planetary exosystems. 2019. hal-02050412v4 HAL Id: hal-02050412 https://hal.archives-ouvertes.fr/hal-02050412v4 Preprint submitted on 7 Aug 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Predictions of planets for 586 exosystems and a method for predicting planets in multi-planetary exosystems Valeri Beck*1 *Alfa Carbon® Beck, Berlin, Germany ABSTRACT We have applied a model of planetary system formation in the field of a standing sound wave (the ‘SSW-Model’) to the prediction of planets in 586 multi-planetary exosystems (384 bi- planetary, 127 tri-planetary and 75 exosystems with four or more confirmed planets). We have verified our predictions using transit-like events from the NASA Threshold-Crossing Event (TCE) catalogue, finding that more than 80% of these events are included in our list of exoplanet predictions. We describe a method for predicting the periods and semi-major axes of additional planets for exosystems with two or more confirmed planets.