Comparative Kbology: Using Surface Spectra of Triton
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GAME of MOONS a TALE of ICE and FIRE 3 × 50 Min
© NASA SCIENCE GAME OF MOONS A TALE OF ICE AND FIRE 3 × 50 min. Written and produced by Ivo Filatsch 4K, 5.1 and Stereo Executive Producer: Sabine Holzer Join us on a spectacular rollercoaster ride through our solar system! This three-part series explores alien worlds of extremes right in our celestial neighbourhood, each single one amazing, fascinating, and unique in its own way. veryone knows the moon — our Moon … case for Triton. It circles around Neptune in the It may come as a surprise, but there are opposite direction — in a retrograde orbit. more than 200 of these natural satellites But this brings a problem: the laws of physics orbiting other planets in the solar system! dictate that in this situation, Triton is being EAll these moons are incredibly different regarding slowed down all the while, this way getting ever their size, but also in terms of their environments. closer to Neptune. Studying these alien worlds in detail is important. Scientists have calculated that in about 100 Thanks to the insights scientists are getting million years from now, Triton will reach its Roche through observations, measurements, and radius. This is the zone where the gravitational conclusions, we all get a better understanding of forces of Neptune will become too strong to our world as a whole. withstand — and Triton will be ripped apart into pieces … And the better we understand our neighbour- hood, the better we get to know our home planet CHAPTER 2: LIFE … Our moon is much more than just a nice decora- tion in the night sky. -
Planetary Report Report
The PLANETARYPLANETARY REPORT REPORT Volume XXI Number 2 March/April 2001 Farewell, Mir Inside— The Planetary Society’s Cosmos 1: The First Solar Sail On the Cover: Volume XXI When Mir launched in February 1986, it was a show- Table of Number 2 case of Russian technology. But after 15 years of hard work, the aged space station has ended its run. Contents March/April 2001 This view of Mir over Earth’s blue skies was imaged during a fly-around by the space shuttle Atlantis follow- ing the joint docking activities between the two crews. Image: JSC/NASA Features Farewell to a Cold Warrior: Mir Station Obituary 4 As head of the Space Research Institute of the Soviet Academy of Sciences, Roald Sagdeev was there at the birth of the Mir space station. As an adviser to Soviet leader Mikhail Gorbachev, he watched Mir’s changing role in international space policy. Then, after marrying From Susan Eisenhower, the American president’s granddaughter, he moved to the United States The and saw Mir from a different perspective. A member of The Planetary Society’s Board of Editor Directors, he shares with Society members his memories of the long-lived space station. 8 A Bold New Voyage: he Planetary Society is preparing to The Planetary Society Prepares to Fly a Solar Sail It’s the first time a membership organization has undertaken an actual space mission, and launch its first space mission: the T only The Planetary Society is audacious enough to do it. This is the story of how we plan to Cosmos 1 solar sail. -
Trans-Neptunian Objects a Brief History, Dynamical Structure, and Characteristics of Its Inhabitants
Trans-Neptunian Objects A Brief history, Dynamical Structure, and Characteristics of its Inhabitants John Stansberry Space Telescope Science Institute IAC Winter School 2016 IAC Winter School 2016 -- Kuiper Belt Overview -- J. Stansberry 1 The Solar System beyond Neptune: History • 1930: Pluto discovered – Photographic survey for Planet X • Directed by Percival Lowell (Lowell Observatory, Flagstaff, Arizona) • Efforts from 1905 – 1929 were fruitless • discovered by Clyde Tombaugh, Feb. 1930 (33 cm refractor) – Survey continued into 1943 • Kuiper, or Edgeworth-Kuiper, Belt? – 1950’s: Pluto represented (K.E.), or had scattered (G.K.) a primordial, population of small bodies – thus KBOs or EKBOs – J. Fernandez (1980, MNRAS 192) did pretty clearly predict something similar to the trans-Neptunian belt of objects – Trans-Neptunian Objects (TNOs), trans-Neptunian region best? – See http://www2.ess.ucla.edu/~jewitt/kb/gerard.html IAC Winter School 2016 -- Kuiper Belt Overview -- J. Stansberry 2 The Solar System beyond Neptune: History • 1978: Pluto’s moon, Charon, discovered – Photographic astrometry survey • 61” (155 cm) reflector • James Christy (Naval Observatory, Flagstaff) – Technologically, discovery was possible decades earlier • Saturation of Pluto images masked the presence of Charon • 1988: Discovery of Pluto’s atmosphere – Stellar occultation • Kuiper airborne observatory (KAO: 90 cm) + 7 sites • Measured atmospheric refractivity vs. height • Spectroscopy suggested N2 would dominate P(z), T(z) • 1992: Pluto’s orbit explained • Outward migration by Neptune results in capture into 3:2 resonance • Pluto’s inclination implies Neptune migrated outward ~5 AU IAC Winter School 2016 -- Kuiper Belt Overview -- J. Stansberry 3 The Solar System beyond Neptune: History • 1992: Discovery of 2nd TNO • 1976 – 92: Multiple dedicated surveys for small (mV > 20) TNOs • Fall 1992: Jewitt and Luu discover 1992 QB1 – Orbit confirmed as ~circular, trans-Neptunian in 1993 • 1993 – 4: 5 more TNOs discovered • c. -
Pluto, Titan, and Triton: How Do Their Haze Properties Compare? B. J. Buratti1, J
51st Lunar and Planetary Science Conference (2020) 1168.pdf Pluto, Titan, and Triton: How do their Haze Properties Compare? B. J. Buratti1, J. D. Hillier2, J. D. Hofgart- ner2, M. D. Hicks1, 1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109; bon- [email protected]; 2Grays Harbor College, Aberdeen, WA 98520. Introduction: The July 2015 encounter of the New Horizons spacecraft with Pluto brought a large Kuiper Belt Object into sharp focus for the first time [1]. In- struments on the spacecraft observed Pluto at solar phase angles not visible from the Earth, where the max- imum solar phase angle is about 2°. The large solar phase angles (>150°), are especially useful for charac- terizing the properties of Pluto’s haze. But key obser- vations were not made during the encounter because of the fast nature of the flyby. These included the small solar phase angles observable from Earth. Thus, the best data set is one consisting of both spacecraft and ground-based data. We have combined Earth-based observations, in- cluding those from the Palomar Adaptive Optics (AO) system, to construct a complete solar phase curve of Figure 1: Charon and Pluto from the Palomar Pluto. Using the classical radiative transfer model of adaptive optics system. Chandrasekhar’s “Planetary Problem” (2,3) we have fit Data from the spacecraft are summarized in Table physical parameters to the surface and haze of Pluto. 2. Comparison with the properties of Titan’s haze shows Table 1- New Horizons Data used in this Study. that both worlds are factories for producing reddish, organic rich molecules. -
Markov Chain Monte-Carlo Orbit Computation for Binary Asteroids
SF2A 2013 L. Cambr´esy,F. Martins, E. Nuss and A. Palacios (eds) MARKOV CHAIN MONTE-CARLO ORBIT COMPUTATION FOR BINARY ASTEROIDS Dagmara Oszkiewicz2; 1, Daniel Hestroffer2 and Pedro David2 Abstract. We present a novel method of orbit computation for resolved binary asteroids. The method combines the Thiele, Innes, van den Bos method with a Markov chain Monte Carlo technique (MCMC). The classical Thiele-van den Bos method has been commonly used in multiple applications before, including orbits of binary stars and asteroids; conversely this novel method can be used for the analysis of binary stars, and of other gravitationally bound binaries. The method requires a minimum of three observations (observing times and relative positions - Cartesian or polar) made at the same tangent plane - or close enough for enabling a first approximation. Further, the use of the MCMC technique for statistical inversion yields the whole bundle of possible orbits, including the one that is most probable. In this new method, we make use of the Metropolis-Hastings algorithm to sample the parameters of the Thiele-van den Bos method, that is the orbital period (or equivalently the double areal constant) together with three randomly selected observations from the same tangent plane. The observations are sampled within their observational errors (with an assumed distribution) and the orbital period is the only parameter that has to be tuned during the sampling procedure. We run multiple chains to ensure that the parameter phase space is well sampled and that the solutions have converged. After the sampling is completed we perform convergence diagnostics. The main advantage of the novel approach is that the orbital period does not need to be known in advance and the entire region of possible orbital solutions is sampled resulting in a maximum likelihood solution and the confidence regions. -
Arxiv:2001.00125V1 [Astro-Ph.EP] 1 Jan 2020
Draft version January 3, 2020 Typeset using LATEX default style in AASTeX61 SIZE AND SHAPE CONSTRAINTS OF (486958) ARROKOTH FROM STELLAR OCCULTATIONS Marc W. Buie,1 Simon B. Porter,1 et al. 1Southwest Research Institute 1050 Walnut St., Suite 300, Boulder, CO 80302 USA To be submitted to Astronomical Journal, Version 1.1, 2019/12/30 ABSTRACT We present the results from four stellar occultations by (486958) Arrokoth, the flyby target of the New Horizons extended mission. Three of the four efforts led to positive detections of the body, and all constrained the presence of rings and other debris, finding none. Twenty-five mobile stations were deployed for 2017 June 3 and augmented by fixed telescopes. There were no positive detections from this effort. The event on 2017 July 10 was observed by SOFIA with one very short chord. Twenty-four deployed stations on 2017 July 17 resulted in five chords that clearly showed a complicated shape consistent with a contact binary with rough dimensions of 20 by 30 km for the overall outline. A visible albedo of 10% was derived from these data. Twenty-two systems were deployed for the fourth event on 2018 Aug 4 and resulted in two chords. The combination of the occultation data and the flyby results provides a significant refinement of the rotation period, now estimated to be 15.9380 ± 0.0005 hours. The occultation data also provided high-precision astrometric constraints on the position of the object that were crucial for supporting the navigation for the New Horizons flyby. This work demonstrates an effective method for obtaining detailed size and shape information and probing for rings and dust on distant Kuiper Belt objects as well as being an important source of positional data that can aid in spacecraft navigation that is particularly useful for small and distant bodies. -
Quaoar from Multi-Chord Stellar Occultations
The Astrophysical Journal, 773:26 (13pp), 2013 August 10 doi:10.1088/0004-637X/773/1/26 C 2013. The American Astronomical Society. All rights reserved. Printed in the U.S.A. THE SIZE, SHAPE, ALBEDO, DENSITY, AND ATMOSPHERIC LIMIT OF TRANSNEPTUNIAN OBJECT (50000) QUAOAR FROM MULTI-CHORD STELLAR OCCULTATIONS F. Braga-Ribas1,2,28, B. Sicardy2,3,J.L.Ortiz4, E. Lellouch2, G. Tancredi5, J. Lecacheux2, R. Vieira-Martins1,6,7, J. I. B. Camargo1, M. Assafin7, R. Behrend8,F.Vachier6, F. Colas6, N. Morales4, A. Maury9, M. Emilio10,A.Amorim11, E. Unda-Sanzana12, S. Roland5, S. Bruzzone5, L. A. Almeida13, C. V. Rodrigues13, C. Jacques14, R. Gil-Hutton15, L. Vanzi16,A.C.Milone13, W. Schoenell4,11, R. Salvo5, L. Almenares5,E.Jehin17, J. Manfroid17, S. Sposetti18, P. Tanga19, A. Klotz20, E. Frappa21, P. Cacella22, J. P. Colque12, C. Neves10, E. M. Alvarez23, M. Gillon17, E. Pimentel14, B. Giacchini14, F. Roques2, T. Widemann2, V. S. Magalhaes˜ 13, A. Thirouin4, R. Duffard4, R. Leiva16, I. Toledo24, J. Capeche5, W. Beisker25, J. Pollock26,C.E.Cedeno˜ Montana˜ 13, K. Ivarsen27, D. Reichart27, J. Haislip27, and A. Lacluyze27 1 Observatorio´ Nacional, Rio de Janeiro, Brazil; [email protected] 2 Observatoire de Paris, LESIA, F-92195 Meudon, France 3 Universite´ Pierre et Marie Curie, F-75252 Paris, France 4 Instituto de Astrof´ısica de Andaluc´ıa-CSIC, E-18080 Granada, Spain 5 Observatorio Astronomico Los Molinos, Montevideo U-12400, Uruguay 6 Observatoire de Paris, IMCCE, F-75014 Paris, France 7 Observatorio´ do Valongo/UFRJ, Rio de Janeiro, Brazil 8 Observatoire -
Download the PDF Preprint
Five New and Three Improved Mutual Orbits of Transneptunian Binaries W.M. Grundya, K.S. Nollb, F. Nimmoc, H.G. Roea, M.W. Buied, S.B. Portera, S.D. Benecchie,f, D.C. Stephensg, H.F. Levisond, and J.A. Stansberryh a. Lowell Observatory, 1400 W. Mars Hill Rd., Flagstaff AZ 86001. b. Space Telescope Science Institute, 3700 San Martin Dr., Baltimore MD 21218. c. Department of Earth and Planetary Sciences, University of California, Santa Cruz CA 95064. d. Southwest Research Institute, 1050 Walnut St. #300, Boulder CO 80302. e. Planetary Science Institute, 1700 E. Fort Lowell, Suite 106, Tucson AZ 85719. f. Carnegie Institution of Washington, Department of Terrestrial Magnetism, 5241 Broad Branch Rd. NW, Washington DC 20015. g. Dept. of Physics and Astronomy, Brigham Young University, N283 ESC Provo UT 84602. h. Steward Observatory, University of Arizona, 933 N. Cherry Ave., Tucson AZ 85721. — Published in 2011: Icarus 213, 678-692. — doi:10.1016/j.icarus.2011.03.012 ABSTRACT We present three improved and five new mutual orbits of transneptunian binary systems (58534) Logos-Zoe, (66652) Borasisi-Pabu, (88611) Teharonhiawako-Sawiskera, (123509) 2000 WK183, (149780) Altjira, 2001 QY297, 2003 QW111, and 2003 QY90 based on Hubble Space Tele- scope and Keck II laser guide star adaptive optics observations. Combining the five new orbit solutions with 17 previously known orbits yields a sample of 22 mutual orbits for which the period P, semimajor axis a, and eccentricity e have been determined. These orbits have mutual periods ranging from 5 to over 800 days, semimajor axes ranging from 1,600 to 37,000 km, ec- centricities ranging from 0 to 0.8, and system masses ranging from 2 × 1017 to 2 × 1022 kg. -
Mass of the Kuiper Belt · 9Th Planet PACS 95.10.Ce · 96.12.De · 96.12.Fe · 96.20.-N · 96.30.-T
Celestial Mechanics and Dynamical Astronomy manuscript No. (will be inserted by the editor) Mass of the Kuiper Belt E. V. Pitjeva · N. P. Pitjev Received: 13 December 2017 / Accepted: 24 August 2018 The final publication ia available at Springer via http://doi.org/10.1007/s10569-018-9853-5 Abstract The Kuiper belt includes tens of thousands of large bodies and millions of smaller objects. The main part of the belt objects is located in the annular zone between 39.4 au and 47.8 au from the Sun, the boundaries correspond to the average distances for orbital resonances 3:2 and 2:1 with the motion of Neptune. One-dimensional, two-dimensional, and discrete rings to model the total gravitational attraction of numerous belt objects are consid- ered. The discrete rotating model most correctly reflects the real interaction of bodies in the Solar system. The masses of the model rings were determined within EPM2017—the new version of ephemerides of planets and the Moon at IAA RAS—by fitting spacecraft ranging observations. The total mass of the Kuiper belt was calculated as the sum of the masses of the 31 largest trans-neptunian objects directly included in the simultaneous integration and the estimated mass of the model of the discrete ring of TNO. The total mass −2 is (1.97 ± 0.30) · 10 m⊕. The gravitational influence of the Kuiper belt on Jupiter, Saturn, Uranus and Neptune exceeds at times the attraction of the hypothetical 9th planet with a mass of ∼ 10 m⊕ at the distances assumed for it. -
ÉRIS Thèmes De Sa Découverte
Carmela Di Martine – Juin 2020 ÉRIS Thèmes de sa découverte Astronomie La première prise de cliché de l’astre date du 3 septembre 1954 au Mont Palomar en Californie. Éris a été ensuite photographiée lors d’observations effectuées le 21 octobre 2003, avec le télescope Oschin du Mont Palomar par l’équipe de Mike Brown, Chadwick Trujillo et David Rabinowitz. Mais ce n’est en fait que le 5 janvier 2005 qu’elle fut vraiment découverte, lorsque des photographies du même pan de ciel révélèrent son déplacement. Éris et Dysnomie Sous la désignation provisoire 2003 UB313 est officiellement classé « planète naine » le 24 août 2006 par l’Union astronomique internationale. Après avoir été désignée sous différents noms (Xena, Lila, Perséphone, Érèbe...), le « choix » final de la dénomination d’Éris par l’UAI, le 13 septembre 2006, évoque aussi d’une part les discussions et controverses acharnées entre scientifiques sur la remise en cause de la définition du mot « planète » du fait de sa découverte, et d’autre part, l’apparente diversité des orbites des objets épars de cette zone du Système solaire (au-delà de la ceinture de Kuiper) par rapport aux orbites régulières des planètes plus proches du Soleil (jusqu’à Neptune). Sa désignation scientifique officielle complète est (136199) Éris. Pour les principales caractéristiques d’Éris, lire aussi mon article : « Les planètes » (p. 25-27). Astrologie N’aurait-on pas une vision "patriarcale" d’Éris ? Éris la "semeuse de Discordes"… Éris, "l’Emmerdeuse"… Expressions très, trop facilement accordées aussi aux femmes par les hommes… Car des questions se posent tout de même… Pourquoi n’est-ce pas Thétis la « plus Belle » en ce jour de son mariage ? Pourquoi le choix d’Aphrodite embarrasse tant toute l’Assemblé divine qui n’en est pourtant pas habituellement à une guerre près ? Contre toute attente, les thèmes de découvertes d’Éris vont nous dévoiler en effet une toute autre vérité…. -
1 Sednan Day = 10.273 Earth Hours (French)
Welcome to a scale model of our solar system. Sedna In the model, this circle shows Sedna is a trans-Neptunian object (an object that on average orbits the relative size of the Sun. The farther from the Sun than Neptune) discovered on November 14, distances between panels show the 2003 by Michael Brown, Chad Trujillo and David Rabinowitz. relative distances between solar system Sedna has a very elongated orbit, more like a comet than a planet, French translation of text in Sun at upper left corner of panel. objects. The panels for the Sun, Earth and takes over twelve thousand years just to orbit the Sun once. and other planets are located on the It is composed mostly of ices which for unknown reasons are Keele campus. The object Sedna is so far from the Sun that almost as red as the surface of Mars. The temperature on Sedna it is located at Glendon never gets warmer than -240 C (33 degrees above absolute zero). in this scale model. Because it is the coldest, most distant place known in the solar NASA / JPL - system, Sedna was named after the Inuit goddess of the sea, who Caltech / R. Hurt The false-color image to the right, our The four panels above (moving clockwise from the upper left) repeatedly zoom out to best photo of Sedna to date, was taken is thought to live at the bottom of the frigid arctic ocean. with the Hubble Space Telescope. place Sedna in context. The first panel shows the orbits of the inner planets and Jupiter. -
Relatório De Conferência De Produção Intelectual
Relatório de Conferência de Produção Intelectual Dados Gerais Instituição de Ensino: OBSERVATÓRIO NACIONAL (ON) Programa: ASTRONOMIA (31013015001P9) Ano de Referência: 2017 Produções Intelectuais Produção: A GRAVITATIONAL-WAVE STANDARD SIREN MEASUREMENT OF THE HUBBLE CONSTANT AUTHORS: Instituição de Ensino: OBSERVATÓRIO NACIONAL (ON) Programa: ASTRONOMIA (31013015001P9) Ano da Publicação: 2017 A Produção é vinculada a Trabalho de Conclusão concluído: Não É um dos 5 trabalhos mais relevantes do seu programa: Não Autores Ordem Nome Categoria 1 B. P Abbott Sem Categoria 2 MARCIO ANTONIO GEIMBA MAIA DOCENTE 3 RICARDO LOURENCO CORREIA DOCENTE OGANDO 4 LUIZ ALBERTO NICOLACI DA COSTA PARTICIPANTE EXTERNO Detalhamento Tipo: BIBLIOGRÁFICA Subtipo: ARTIGO EM PERIÓDICO ISSN: 1476-4687 Estrato: - Natureza: Completo ISSN / Título do periódico: (1476-4687) NATURE (ONLINE) Nome da editora: Cidade: Volume: 551 Fascículo: Série: Número da página inicial: Número da página final: Idioma: inglês Divulgação: VÁRIOS URL: Observação: Trata-se de um artigo com mais de 30 autores. Apenas os autores vinculados ao Observatório Nacional foram listados. Este artigo é fruto de uma grande colaboração. 10/01/2019 14:14:50 1 Relatório de Conferência de Produção Intelectual DOI: 10.1038/nature24471 Contexto Área de Concentração: ASTROFISICA Linha de Pesquisa: ASTROFÍSICA EXTRAGALÁCTICA Projeto de Pesquisa: Produção: A MODIFIED COROT DETREND ALGORITHM AND THE DISCOVERY OF A NEW PLANETARY COMPANION Instituição de Ensino: OBSERVATÓRIO NACIONAL (ON) Programa: ASTRONOMIA (31013015001P9) Ano da Publicação: 2017 A Produção é vinculada a Trabalho de Conclusão concluído: Sim É um dos 5 trabalhos mais relevantes do seu programa: Sim Autores Ordem Nome Categoria 1 RODRIGO CARLOS BOUFLEUR DISCENTE 2 MARCELO EMILIO DOCENTE 3 EDUARDO JANOT PACHECO PARTICIPANTE EXTERNO 4 LAERTE BRANDAO PAES DE ANDRADE PARTICIPANTE EXTERNO 5 SYLVIO FERRAZ DE MELLO PARTICIPANTE EXTERNO 6 José Dias do Nascimento Jr.