New Transit Measurements of WASP 43B and HD 189733B
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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. -
Stellar Magnetic Activity – Star-Planet Interactions
EPJ Web of Conferences 101, 005 02 (2015) DOI: 10.1051/epjconf/2015101005 02 C Owned by the authors, published by EDP Sciences, 2015 Stellar magnetic activity – Star-Planet Interactions Poppenhaeger, K.1,2,a 1 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambrigde, MA 02138, USA 2 NASA Sagan Fellow Abstract. Stellar magnetic activity is an important factor in the formation and evolution of exoplanets. Magnetic phenomena like stellar flares, coronal mass ejections, and high- energy emission affect the exoplanetary atmosphere and its mass loss over time. One major question is whether the magnetic evolution of exoplanet host stars is the same as for stars without planets; tidal and magnetic interactions of a star and its close-in planets may play a role in this. Stellar magnetic activity also shapes our ability to detect exoplanets with different methods in the first place, and therefore we need to understand it properly to derive an accurate estimate of the existing exoplanet population. I will review recent theoretical and observational results, as well as outline some avenues for future progress. 1 Introduction Stellar magnetic activity is an ubiquitous phenomenon in cool stars. These stars operate a magnetic dynamo that is fueled by stellar rotation and produces highly structured magnetic fields; in the case of stars with a radiative core and a convective outer envelope (spectral type mid-F to early-M), this is an αΩ dynamo, while fully convective stars (mid-M and later) operate a different kind of dynamo, possibly a turbulent or α2 dynamo. These magnetic fields manifest themselves observationally in a variety of phenomena. -
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. -
CONSTELLATION VULPECULA, the (LITTLE) FOX Vulpecula Is a Faint Constellation in the Northern Sky
CONSTELLATION VULPECULA, THE (LITTLE) FOX Vulpecula is a faint constellation in the northern sky. Its name is Latin for "little fox", although it is commonly known simply as the fox. It was identified in the seventeenth century, and is located in the middle of the northern Summer Triangle (an asterism consisting of the bright stars Deneb in Cygnus (the Swan), Vega in Lyra (the Lyre) and Altair in Aquila (the Eagle). Vulpecula was introduced by the Polish astronomer Johannes Hevelius in the late 17th century. It is not associated with any figure in mythology. Hevelius originally named the constellation Vulpecula cum ansere, or Vulpecula et Anser, which means the little fox with the goose. The constellation was depicted as a fox holding a goose in its jaws. The stars were later separated to form two constellations, Anser and Vulpecula, and then merged back together into the present-day Vulpecula constellation. The goose was left out of the constellation’s name, but instead the brightest star, Alpha Vulpeculae, carries the name Anser. It is one of the seven constellations created by Hevelius. The fox and the goose shown as ‘Vulpec. & Anser’ on the Atlas Coelestis of John Flamsteed (1729). The Fox and Goose is a traditional pub name in Britain. STARS There are no stars brighter than 4th magnitude in this constellation. The brightest star is: Alpha Vulpeculae, a magnitude 4.44m red giant at a distance of 297 light-years. The star is an optical binary (separation of 413.7") that can be split using binoculars. The star also carries the traditional name Anser, which refers to the goose the little fox holds in its jaws. -
The Professor Comet's Report Late Summer/Early Autumn – September
The Professor Comet’s Report 1 Messier 71 and C/2009 P1 Garradd © Steve Grimsley of Houston Astronomical Society, 2011 Welcome to the comet report which is a monthly article on the observations of comets by the amateur astronomy community and comet hunters from around the world! This article is dedicated to the latest reports of available comets for observations, current state of those comets, future predictions, & projections for observations in comet astronomy! Late Summer/Early Autumn – September 2011 The Professor Comet’s Report 2 The Current Status of the Predominant Comets for July 2011! Comets Designation Orbital Magnitude Trend Observation Constellations Visibility (IAU – MPC) Status Visual (Range in Lat.) (Night Sky Location) Period Garradd 2009 P1 C 7.0 – 7.2 Getting 60°N – 60°S Between Sagitta and Vulpecula All Night Brighter (heading WNW towards Hercules) Honda – 45P P 8.0 Getting 50°N – 85°S Undergoing a wide retrograde motion! Early Morning Mrkos - Brighter Currently the comet is north of Hydra Pajdusakova heading NE towards Leo Elenin 2010 X1 C 8.6 – 9.4 Getting 45°N – 75°S Currently undergoing retrograde Early Evening Brighter motion in the S region of Leo (Just after Dusk) Crommelin 27P P 9.5 Possibly N/A Poor Elongation N/A Fading? (lost in the daytime glare!) LINEAR 2011 M1 C 10.4 Brightening 60°N – 45°N Moving SE of Ursa Major and All Night heading across the E edge of Leo Minor Hill 2010 G2 C 11.1 Fading 60°N – 10°N Between Ursa Major and Lynx All Night (Moving SSW of Muscida) Gibbs 2011 A3 C 11.4 Brightening 55°N -
A Search for Variability and Transit Signatures In
A SEARCH FOR VARIABILITY AND TRANSIT SIGNATURES IN HIPPARCOS PHOTOMETRIC DATA A thesis presented to the faculty of 3 ^ San Francisco State University Zo\% In partial fulfilment of W* The Requirements for The Degree Master of Science In Physics: Astronomy by Badrinath Thirumalachari San JVancisco, California December 2018 Copyright by Badrinath Thirumalachari 2018 CERTIFICATION OF APPROVAL I certify that I have read A SEARCH FOR VARIABILITY AND TRANSIT SIGNATURES IN HIPPARCOS PHOTOMETRIC DATA by Badrinath Thirumalachari and that in my opinion this work meets the criteria for approving a thesis submitted in partial fulfillment of the requirements for the degree: Master of Science in Physics: Astronomy at San Francisco State University. fov- Dr. Stephen Kane, Ph.D. Astrophysics Associate Professor of Planetary Astrophysics Dr. Uo&eph Barranco, Ph.D. .%trtJphysics Chairfe Associate Professor of Physics K + A Q , L a . Dr. Ron Marzke, Ph.D. Astronomy Assoc. Dean of College of Science & Engineering A SEARCH FOR VARIABILITY AND TRANSIT SIGNATURES IN HIPPARCOS PHOTOMETRIC DATA Badrinath Thirumalachari San Francisco State University 2018 The study and characterization of exoplanets has picked up pace rapidly over the past few decades with the invention of newer techniques and instruments. Detecting transits in stellar photometric data around stars already known to harbor exoplanets is crucial for exoplanet characterization. Due to these advancements we now have oceans of data and coming up with an automated way of performing exoplanet characterization is a challenge. In this thesis I describe one such method to search for transits in Hipparcos dataset containing photometric data for over 118000 stars. The radial velocity method has discovered a lot of planets around bright host stars and a follow up transit detection will give us the density of the exoplanet. -
Transit Polarimetry of Exoplanetary System HD 189733
Transit Polarimetry of Exoplanetary System HD 189733 N.M. Kostogryz1,3, S.V. Berdyugina1,2, T.M. Yakobchuk3 1Kiepenheuer Institut f¨urSonnenphysik, Sch¨oneckstr. 6, 79104 Freiburg, Germany 2NASA Astrobiology Institute, Institute for Astronomy, University of Hawaii, USA 3Main Astronomical Observatory of NAS of Ukraine, Zabolotnoho str. 27, 03680 Kyiv, Ukraine Abstract. We present and discuss a polarimetric effect caused by a planet transiting the stellar disk thus breaking the symmetry of the light distribution and resulting in linear polarization of the partially eclipsed star. Estimates of this effect for transiting planets have been made only recently. In particular, we demonstrate that the maximum polarization during transits depends strongly on the centre-to-limb variation of the linear polarization of the host star. However, observational and theoretical studies of the limb polarization have largely concentrated on the Sun. Here we solve the radiative transfer problem for polarized light and calculate the centre-to-limb polarization for one of the brightest transiting planet host HD 189733 taking into account various opacities. Using that we simulate the transit effect and estimate the variations of the flux and the linear polarization for HD 189733 during the event. As the spots on the stellar disk also break the limb polarization symmetry we simulate the flux and polarization variation due to the spots on the stellar disk. 1. Introduction HD 189733 is currently the brightest (mV = 7.67mag) star known to harbour a transiting exoplanet (Bouchy et al. 2005). This, along with the short period (2.2 days) and large ratio of planet-to-star radii (Rpl/R⋆ ≈ 0.15), makes it very suitable for different types of observations including polarimetry (Berdyugina et al. -
00E the Construction of the Universe Symphony
The basic construction of the Universe Symphony. There are 30 asterisms (Suites) in the Universe Symphony. I divided the asterisms into 15 groups. The asterisms in the same group, lay close to each other. Asterisms!! in Constellation!Stars!Objects nearby 01 The W!!!Cassiopeia!!Segin !!!!!!!Ruchbah !!!!!!!Marj !!!!!!!Schedar !!!!!!!Caph !!!!!!!!!Sailboat Cluster !!!!!!!!!Gamma Cassiopeia Nebula !!!!!!!!!NGC 129 !!!!!!!!!M 103 !!!!!!!!!NGC 637 !!!!!!!!!NGC 654 !!!!!!!!!NGC 659 !!!!!!!!!PacMan Nebula !!!!!!!!!Owl Cluster !!!!!!!!!NGC 663 Asterisms!! in Constellation!Stars!!Objects nearby 02 Northern Fly!!Aries!!!41 Arietis !!!!!!!39 Arietis!!! !!!!!!!35 Arietis !!!!!!!!!!NGC 1056 02 Whale’s Head!!Cetus!! ! Menkar !!!!!!!Lambda Ceti! !!!!!!!Mu Ceti !!!!!!!Xi2 Ceti !!!!!!!Kaffalijidhma !!!!!!!!!!IC 302 !!!!!!!!!!NGC 990 !!!!!!!!!!NGC 1024 !!!!!!!!!!NGC 1026 !!!!!!!!!!NGC 1070 !!!!!!!!!!NGC 1085 !!!!!!!!!!NGC 1107 !!!!!!!!!!NGC 1137 !!!!!!!!!!NGC 1143 !!!!!!!!!!NGC 1144 !!!!!!!!!!NGC 1153 Asterisms!! in Constellation Stars!!Objects nearby 03 Hyades!!!Taurus! Aldebaran !!!!!! Theta 2 Tauri !!!!!! Gamma Tauri !!!!!! Delta 1 Tauri !!!!!! Epsilon Tauri !!!!!!!!!Struve’s Lost Nebula !!!!!!!!!Hind’s Variable Nebula !!!!!!!!!IC 374 03 Kids!!!Auriga! Almaaz !!!!!! Hoedus II !!!!!! Hoedus I !!!!!!!!!The Kite Cluster !!!!!!!!!IC 397 03 Pleiades!! ! Taurus! Pleione (Seven Sisters)!! ! ! Atlas !!!!!! Alcyone !!!!!! Merope !!!!!! Electra !!!!!! Celaeno !!!!!! Taygeta !!!!!! Asterope !!!!!! Maia !!!!!!!!!Maia Nebula !!!!!!!!!Merope Nebula !!!!!!!!!Merope -
Desert Skies Tucson Amateur Astronomy Association
Desert Skies Tucson Amateur Astronomy Association Volume LIII, Number 10 October, 2007 Spitzer Space Telescope Studies Binary Stars ♦ Learn about the ♦ Constellation of the month ♦ School star parties ♦ All-Arizona Star Party ♦ Opportunities to Volunteer Cover Photo: Artist concept of the circumbinary disk. Credit: P. Marenfeld and NOAO/AURA/NSF, http://www.noao.edu/ outreach/press/pr06/pr0604.html TAAA Web Page: http://www.tucsonastronomy.org TAAA Phone Number: (520) 792-6414 Office/Position Name Phone E-mail Address President Bill Lofquist 297-6653 [email protected] Vice President Ken Shaver 762-5094 [email protected] Secretary Steve Marten 307-5237 [email protected] Treasurer Terri Lappin 977-1290 [email protected] Member-at-Large George Barber 822-2392 [email protected] Member-at-Large Keith Schlottman 290-5883 [email protected] Member-at-Large Teresa Plymate 883-9113 [email protected] Chief Observer Wayne Johnson 586-2244 [email protected] AL Correspondent (ALCor) Nick de Mesa 797-6614 [email protected] Astro-Imaging SIG Steve Peterson 762-8211 [email protected] Computers in Astronomy SIG Roger Tanner 574-3876 [email protected] Beginners SIG JD Metzger 760-8248 [email protected] Newsletter Editor George Barber 822-2392 [email protected] School Star Party Scheduling Coordinator Paul Moss 240-2084 [email protected] School Star Party Volunteer Coordinator Claude -
Desert Skies
Tucson Amateur Astronomy Association Volume LVIII, Number 10 October 2012 Impact Craters in the Solar System Valhalla crater on Callisto Gale crater on Mars Herschel crater on Mimas Endeavor Over Tucson! Barringer Crater, Winslow, AZ Kitt Peak Star-B-Que & Star Party Chiricahua Astronomy Complex Report Pages 4 Page 7 2013 TAAA Calendars Coming Soon Community Star Parties Scheduled Page 3 Page 6 General Meeting October 5th Steward Observatory Lecture Hall, Room N210 6:30pm Space Weather — Terri Lappin, TAAA 7:30pm The dramatic formation of Gale crater: What happens when a meteor hits a planet? — Dr Veronica Bray, UA LPL Affiliates Volume LVIII, Number 10 2 Desert Skies October 2012 TAAA Meeting Friday, Oct 5 Steward Observatory Lecture Hall, Room N210, U of A campus 6:30pm Astronomy Essentials Lecture Title: Space Weather Speaker: Terri Lappin, TAAA Construction Alert! Most of us want to hear a daily weather report. It may The construction mess on campus determine what we wear and to some level, what we do during has improved since the summer. the day. In some ways, space weather is similar to atmospheric The Cherry and 2nd Street weather—predictions can be made, and those predictions intersection is open, but much of 2nd Street iremains change our behavior. However, space weather is a totally closed. First Street is two-way traffic. The 2nd Street different animal! This animal will likely never be tamed. Come garage is accessible but it’s best to check the UA learn about space weather, how it’s monitored, and how it website to find out how (recently it’s been from the affects you. -
A Tale of Two Exoplanets: the Inflated Atmospheres of the Hot Jupiters HD 189733 B and Corot-2 B
A Tale of Two Exoplanets: the Inflated Atmospheres of the Hot Jupiters HD 189733 b and CoRoT-2 b K. Poppenhaeger1,3, S.J. Wolk1, J.H.M.M. Schmitt2 1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 2Hamburger Sternwarte, Gojenbergsweg 112, 21029 Hamburg, Germany 3NASA Sagan Fellow Abstract. Planets in close orbits around their host stars are subject to strong irradiation. High-energy irradiation, originating from the stellar corona and chromosphere, is mainly responsible for the evaporation of exoplanetary atmospheres. We have conducted mul- tiple X-ray observations of transiting exoplanets in short orbits to determine the extent and heating of their outer planetary atmospheres. In the case of HD 189733 b, we find a surprisingly deep transit profile in X-rays, indicating an atmosphere extending out to 1.75 optical planetary radii. The X-ray opacity of those high-altitude layers points towards large densities or high metallicity. We preliminarily report on observations of the Hot Jupiter CoRoT-2 b from our Large Program with XMM-Newton, which was conducted recently. In addition, we present results on how exoplanets may alter the evolution of stellar activity through tidal interaction. 1. Exoplanetary transits in X-rays Close-in exoplanets are expected to harbor extended atmospheres and in some cases lose mass through atmospheric evaporation, driven by X-ray and extreme UV emission from the host star (Lecavelier des Etangs et al. 2004; Murray-Clay et al. 2009, for exmaple). Direct observational evidence for such extended atmospheres has been collected at UV wavelengths (Vidal-Madjar et al. -
Astronomical Coordinate Systems
Appendix 1 Astronomical Coordinate Systems A basic requirement for studying the heavens is being able to determine where in the sky things are located. To specify sky positions, astronomers have developed several coordinate systems. Each sys- tem uses a coordinate grid projected on the celestial sphere, which is similar to the geographic coor- dinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth’s equator). Each coordinate system is named for its choice of fundamental plane. The Equatorial Coordinate System The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the most closely related to the geographic coordinate system because they use the same funda- mental plane and poles. The projection of the Earth’s equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles onto the celestial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate sys- tems: the geographic system is fixed to the Earth and rotates as the Earth does. The Equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but it’s really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec. for short). It measures the angle of an object above or below the celestial equator.