March 2019 Issue
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Arxiv:1910.11169V1 [Astro-Ph.EP] 24 Oct 2019 Metchev Et Al.(2004) Due to the Detection of a Strong Mid- Tinuum and at HCO+ and CO Gas Emission Lines
Astronomy & Astrophysics manuscript no. PDS70_v2 c ESO 2019 October 25, 2019 VLT/SPHERE exploration of the young multiplanetary system PDS70? D. Mesa1, M. Keppler2, F. Cantalloube2, L. Rodet3, B. Charnay4, R. Gratton1, M. Langlois5; 6, A. Boccaletti4, M. Bonnefoy3, A. Vigan6, O. Flasseur7, J. Bae8, M. Benisty3; 9, G. Chauvin3; 9, J. de Boer10, S. Desidera1, T. Henning2, A.-M. Lagrange3, M. Meyer11, J. Milli12, A. Müller2, B. Pairet13, A. Zurlo14; 15; 6, S. Antoniucci16, J.-L. Baudino17, S. Brown Sevilla2, E. Cascone18, A. Cheetham19, R.U. Claudi1, P. Delorme3, V. D’Orazi1, M. Feldt2, J. Hagelberg19, M. Janson20, Q. Kral4, E. Lagadec21, C. Lazzoni1, R. Ligi22, A.-L. Maire2; 23, P. Martinez21, F. Menard3, N. Meunier3, C. Perrot4; 24; 25, S. Petrus3, C. Pinte26; 3, E.L. Rickman19, S. Rochat3, D. Rouan4, M. Samland2; 20, J.-F. Sauvage27; 6, T. Schmidt4; 28, S. Udry19, L. Weber19, F. Wildi19 (Affiliations can be found after the references) Received / accepted ABSTRACT Context. PDS 70 is a young (5.4 Myr), nearby (∼113 pc) star hosting a known transition disk with a large gap. Recent observations with SPHERE and NACO in the near-infrared (NIR) allowed us to detect a planetary mass companion, PDS 70 b, within the disk cavity. Moreover, observations in Hα with MagAO and MUSE revealed emission associated to PDS 70 b and to another new companion candidate, PDS 70 c, at a larger separation from the star. PDS 70 is the only multiple planetary system at its formation stage detected so far through direct imaging. Aims. Our aim is to confirm the discovery of the second planet PDS 70 c using SPHERE at VLT, to further characterize its physical properties, and search for additional point sources in this young planetary system. -
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. -
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. -
Crater Gradation in Gusev Crater and Meridiani Planum, Mars J
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 111, E02S08, doi:10.1029/2005JE002465, 2006 Crater gradation in Gusev crater and Meridiani Planum, Mars J. A. Grant,1 R. E. Arvidson,2 L. S. Crumpler,3 M. P. Golombek,4 B. Hahn,5 A. F. C. Haldemann,4 R. Li,6 L. A. Soderblom,7 S. W. Squyres,8 S. P. Wright,9 and W. A. Watters10 Received 19 April 2005; revised 21 June 2005; accepted 27 June 2005; published 6 January 2006. [1] The Mars Exploration Rovers investigated numerous craters in Gusev crater and Meridiani Planum during the first 400 sols of their missions. Craters vary in size and preservation state but are mostly due to secondary impacts at Gusev and primary impacts at Meridiani. Craters at both locations are modified primarily by eolian erosion and infilling and lack evidence for modification by aqueous processes. Effects of gradation on crater form are dependent on size, local lithology, slopes, and availability of mobile sediments. At Gusev, impacts into basaltic rubble create shallow craters and ejecta composed of resistant rocks. Ejecta initially experience eolian stripping, which becomes weathering-limited as lags develop on ejecta surfaces and sediments are trapped within craters. Subsequent eolian gradation depends on the slow production of fines by weathering and impacts and is accompanied by minor mass wasting. At Meridiani the sulfate-rich bedrock is more susceptible to eolian erosion, and exposed crater rims, walls, and ejecta are eroded, while lower interiors and low-relief surfaces are increasingly infilled and buried by mostly basaltic sediments. Eolian processes outpace early mass wasting, often produce meters of erosion, and mantle some surfaces. -
ISPY-NACO Imaging Survey for Planets Around Young Stars Survey Description and Results from the first 2.5 Years of Observations? R
A&A 635, A162 (2020) Astronomy https://doi.org/10.1051/0004-6361/201937000 & © R. Launhardt et al. 2020 Astrophysics ISPY-NACO Imaging Survey for Planets around Young stars Survey description and results from the first 2.5 years of observations? R. Launhardt1, Th. Henning1, A. Quirrenbach2, D. Ségransan3, H. Avenhaus4,1, R. van Boekel1, S. S. Brems2, A. C. Cheetham1,3, G. Cugno4, J. Girard5, N. Godoy8,11, G. M. Kennedy6, A.-L. Maire1,10, S. Metchev7, A. Müller1, A. Musso Barcucci1, J. Olofsson8,11, F. Pepe3, S. P. Quanz4, D. Queloz9, S. Reffert2, E. L. Rickman3, H. L. Ruh2, and M. Samland1,12 1 Max-Planck-Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany e-mail: [email protected] 2 Landessternwarte, Zentrum für Astronomie der Universität Heidelberg, Königstuhl 12, 69117 Heidelberg, Germany 3 Observatoire Astronomique de l’Université de Genève, 51 Ch. des Maillettes, 1290 Versoix, Switzerland 4 ETH Zürich, Institute for Particle Physics and Astrophysics, Wolfgang-Pauli-Str. 27, 8093 Zürich, Switzerland 5 Space Telescope Science Institute, Baltimore 21218, MD, USA 6 Department of Physics & Centre for Exoplanets and Habitability, University of Warwick, Coventry, UK 7 The University of Western Ontario, Department of Physics and Astronomy, 1151 Richmond Avenue, London, ON N6A 3K7, Canada 8 Instituto de Física y Astronomía, Facultad de Ciencias, Universidad de Valparaíso, Av. Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile 9 Cavendish Laboratory, J J Thomson Avenue, Cambridge, CB3 0HE, UK 10 STAR Institute, University of Liège, Allée du Six Août 19c, 4000 Liège, Belgium 11 Núcleo Milenio Formación Planetaria – NPF, Universidad de Valparaíso, Av. -
Annual Report 2016–2017 AAVSO
AAVSO The American Association of Variable Star Observers Annual Report 2016–2017 AAVSO Annual Report 2012 –2013 The American Association of Variable Star Observers AAVSO Annual Report 2016–2017 The American Association of Variable Star Observers 49 Bay State Road Cambridge, MA 02138-1203 USA Telephone: 617-354-0484 Fax: 617-354-0665 email: [email protected] website: https://www.aavso.org Annual Report Website: https://www.aavso.org/annual-report On the cover... At the 2017 AAVSO Annual Meeting.(clockwise from upper left) Knicole Colon, Koji Mukai, Dennis Conti, Kristine Larsen, Joey Rodriguez; Rachid El Hamri, Andy Block, Jane Glanzer, Erin Aadland, Jamin Welch, Stella Kafka; and (clockwise from upper left) Joey Rodriguez, Knicole Colon, Koji Mukai, Frans-Josef “Josch” Hambsch, Chandler Barnes. Picture credits In additon to images from the AAVSO and its archives, the editors gratefully acknowledge the following for their image contributions: Glenn Chaple, Shawn Dvorak, Mary Glennon, Bill Goff, Barbara Harris, Mario Motta, NASA, Gary Poyner, Msgr. Ronald Royer, the Mary Lea Shane Archives of the Lick Observatory, Chris Stephan, and Wheatley, et al. 2003, MNRAS, 345, 49. Table of Contents 1. About the AAVSO Vision and Mission Statement 1 About the AAVSO 1 What We Do 2 What Are Variable Stars? 3 Why Observe Variable Stars? 3 The AAVSO International Database 4 Observing Variable Stars 6 Services to Astronomy 7 Education and Outreach 9 2. The Year in Review Introduction 11 The 106th AAVSO Spring Membership Meeting, Ontario, California 11 The -
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. -
Sdlao Uemoa Uicn
DiagnosticDiagnostic 4 FOR THE WEST AFRICAN COASTAL AREA THEWESTAFRICANFOR COASTAL REGIONAL SHORELINE MONITORING MONITORING SHORELINE REGIONAL STUDY AND DRAWING UP OF A UPOF STUDY ANDDRAWING REGIONAL DIAGNOSTIC MANAGEMENT SCHEME 2010 REGIONAL SHORELINE MONITORING STUDY AND DRAWING UP OF A MANAGEMENT SCHEME FOR THE WEST AFRICAN COASTAL AREA The regional study for shoreline monitoring and drawing up a development scheme for the West African coastal area was launched by UEMOA as part of the regional programme to combat coastal erosion (PRLEC – UEMOA), the subject of Regulation 02/2007/CM/UEMOA, adopted on 6 April 2007. This decision also follows on from the recommendations from the Conference of Ministers in charge of the Environment dated 11 April 1997, in Cotonou. The meeting of Ministers in charge of the environment, held on 25 January 2007, in Cotonou (Benin), approved this Regional coastal erosion programme in its conclusions. This study is implemented by the International Union for the IUCN, International Union for Conservation of Nature (UICN) as part of the remit of IUCN’s Marine Conservation of Nature, helps the and Coastal Programme (MACO) for Central and Western Africa, the world find pragmatic solutions to coordination of which is based in Nouakchott and which is developed our most pressing environment as a thematic component of IUCN’s Programme for Central and and development challenges. It supports scientific research, Western Africa (PACO), coordinated from Ouagadougou. manages field projects all over the world and brings governments, UEMOA is the contracting owner of the study, in this instance non-government organizations, through PRLEC – UEMOA coordination of the UEMOA United Nations agencies, Commission. -
Observing Exoplanets
Observing Exoplanets Olivier Guyon University of Arizona Astrobiology Center, National Institutes for Natural Sciences (NINS) Subaru Telescope, National Astronomical Observatory of Japan, National Institutes for Natural Sciences (NINS) Nov 29, 2017 My Background Astronomer / Optical scientist at University of Arizona and Subaru Telescope (National Astronomical Observatory of Japan, Telescope located in Hawaii) I develop instrumentation to find and study exoplanet, for ground-based telescopes and space missions My interest is focused on habitable planets and search for life outside our solar system At Subaru Telescope, I lead the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument. 2 ALL known Planets until 1989 Approximately 10% of stars have a potentially habitable planet 200 billion stars in our galaxy → approximately 20 billion habitable planets Imagine 200 explorers, each spending 20s on each habitable planet, 24hr a day, 7 days a week. It would take >60yr to explore all habitable planets in our galaxy alone. x 100,000,000,000 galaxies in the observable universe Habitable planets Potentially habitable planet : – Planet mass sufficiently large to retain atmosphere, but sufficiently low to avoid becoming gaseous giant – Planet distance to star allows surface temperature suitable for liquid water (habitable zone) Habitable zone = zone within which Earth-like planet could harbor life Location of habitable zone is function of star luminosity L. For constant stellar flux, distance to star scales as L1/2 Examples: Sun → habitable zone is at ~1 AU Rigel (B type star) Proxima Centauri (M type star) Habitable planets Potentially habitable planet : – Planet mass sufficiently large to retain atmosphere, but sufficiently low to avoid becoming gaseous giant – Planet distance to star allows surface temperature suitable for liquid water (habitable zone) Habitable zone = zone within which Earth-like planet could harbor life Location of habitable zone is function of star luminosity L. -
New Planetary Science from Dawn, Rosetta, and New Horizons
New Planetary Science from Dawn, Rosetta, and New Horizons We have many active probes exploring deep space now. Image: The Planetary Society Three of them are giving us great new science from minor planets. ●Dawn ● NASA mission ● Asteroid Vesta and asteroid and dwarf planet Ceres ● First asteroid orbiter ● First to orbit two different deep space targets ●Rosetta ● European Space Agency mission ● Comet 67P/Churyumov–Gerasimenko ● First comet orbiter and landing ● Hopes the be the first to make two landings on a comet ●New Horizons ● NASA mission ● Dwarf planet Pluto and other Kuiper belt objects beyond ● First mission to Pluto But first, a surprise guest appearance by Messenger ●Launched August 2004 by NASA. ●March 2011 arrived at Mercury. ●April 2015 crashed into Mercury. Photo: NASA Significant Science by Messenger at Mercury ●Crashed into the planet April 30 2015. ●For earlier mission highlights, see RAC program by Brenda Conway October 2011. ●Last few orbits were as low as possible. ●Highest resolution photos ever of the surface. ●Unexpected discovery that Mercury's magnetic field grows and shrinks in response to the Sun's level of activity. Significant Science by Messenger at Mercury ●Discovered unexpected hollows on the surface. ●Younger than impact craters around them (some are in or on craters - the surface collapsed some time after the impact). ●Mercury was believed to be geologically inactive. ● First evidence there are dynamic processes on the surface of Mercury today. Photo: NASA Significant Science by Messenger at Mercury ● The last image sent by Messenger before its crash. Photo: NASA Dawn ●Launched September 2007. ●February 2009 Mars flyby and gravity assist. -
Dawn/Dusk Asymmetry of the Martian Ultraviolet Terminator Observed Through Suprathermal Electron Depletions Morgane Steckiewicz, P
Dawn/dusk asymmetry of the Martian UltraViolet terminator observed through suprathermal electron depletions Morgane Steckiewicz, P. Garnier, R. Lillis, D. Toublanc, François Leblanc, D. L. Mitchell, L. Andersson, Christian Mazelle To cite this version: Morgane Steckiewicz, P. Garnier, R. Lillis, D. Toublanc, François Leblanc, et al.. Dawn/dusk asymme- try of the Martian UltraViolet terminator observed through suprathermal electron depletions. Journal of Geophysical Research Space Physics, American Geophysical Union/Wiley, 2019, 124 (8), pp.7283- 7300. 10.1029/2018JA026336. insu-02189085 HAL Id: insu-02189085 https://hal-insu.archives-ouvertes.fr/insu-02189085 Submitted on 29 Mar 2021 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. RESEARCH ARTICLE Dawn/Dusk Asymmetry of the Martian UltraViolet 10.1029/2018JA026336 Terminator Observed Through Suprathermal Key Points: • The approximate position of the Electron Depletions UltraViolet terminator can be M. Steckiewicz1 , P. Garnier1 , R. Lillis2 , D. Toublanc1, F. Leblanc3 , D. L. Mitchell2 , determined