Quantifying the Uncertainty in the Orbits of Extrasolar Planets
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Where Are the Distant Worlds? Star Maps
W here Are the Distant Worlds? Star Maps Abo ut the Activity Whe re are the distant worlds in the night sky? Use a star map to find constellations and to identify stars with extrasolar planets. (Northern Hemisphere only, naked eye) Topics Covered • How to find Constellations • Where we have found planets around other stars Participants Adults, teens, families with children 8 years and up If a school/youth group, 10 years and older 1 to 4 participants per map Materials Needed Location and Timing • Current month's Star Map for the Use this activity at a star party on a public (included) dark, clear night. Timing depends only • At least one set Planetary on how long you want to observe. Postcards with Key (included) • A small (red) flashlight • (Optional) Print list of Visible Stars with Planets (included) Included in This Packet Page Detailed Activity Description 2 Helpful Hints 4 Background Information 5 Planetary Postcards 7 Key Planetary Postcards 9 Star Maps 20 Visible Stars With Planets 33 © 2008 Astronomical Society of the Pacific www.astrosociety.org Copies for educational purposes are permitted. Additional astronomy activities can be found here: http://nightsky.jpl.nasa.gov Detailed Activity Description Leader’s Role Participants’ Roles (Anticipated) Introduction: To Ask: Who has heard that scientists have found planets around stars other than our own Sun? How many of these stars might you think have been found? Anyone ever see a star that has planets around it? (our own Sun, some may know of other stars) We can’t see the planets around other stars, but we can see the star. -
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. -
The Search for Extrasolar Planets
zucker 16-12-2005 11:22 Pagina 229 229 The Search for Extrasolar Planets S. Zucker and M. Mayor Observatoire de Genève, Sauverny, Switzerland During the recent decade, the question of the existence of planets orbiting stars other than our Sun has been answered unequivocally. About 150 extrasolar plan- ets have been detected since 1995, and their properties are the subject of wide interest in the research community. Planet formation and evolution theories are adjusting to the constantly emerging data, and astronomers are seeking new ways to widen the sample and enrich the data about the known planets. In September 2002, ISSI organized a workshop focusing on the physics of “Planetary Systems and Planets in Systems”1. The present contribution is an attempt to give a broader overview of the researches in the field of exoplanets and results obtained in the decade after the discovery of the planet 51 Peg b. The existence of planets orbiting other stars was speculated upon even in the 4th century BC, when Epicurus and Aristotle debated it using their early notions about our world. Epicurus claimed that the infinity of the Universe compelled the existence of other worlds. After the Copernican Revolution, Giordano Bruno wrote: “Innumerable suns exist; innumerable earths revolve around these suns in a manner similar to the way the seven planets revolve around our Sun”. Aitken2 examined the observational problem of detecting extrasolar planets. He showed that their detection, either directly or indirectly, lay beyond the techni- cal horizon of his era. The basic difficulty in directly detecting planets lies in the brightness ratio between a typical planet and its host star, a ratio that can be as low as 10-8. -
Arxiv:0809.1275V2
How eccentric orbital solutions can hide planetary systems in 2:1 resonant orbits Guillem Anglada-Escud´e1, Mercedes L´opez-Morales1,2, John E. Chambers1 [email protected], [email protected], [email protected] ABSTRACT The Doppler technique measures the reflex radial motion of a star induced by the presence of companions and is the most successful method to detect ex- oplanets. If several planets are present, their signals will appear combined in the radial motion of the star, leading to potential misinterpretations of the data. Specifically, two planets in 2:1 resonant orbits can mimic the signal of a sin- gle planet in an eccentric orbit. We quantify the implications of this statistical degeneracy for a representative sample of the reported single exoplanets with available datasets, finding that 1) around 35% percent of the published eccentric one-planet solutions are statistically indistinguishible from planetary systems in 2:1 orbital resonance, 2) another 40% cannot be statistically distinguished from a circular orbital solution and 3) planets with masses comparable to Earth could be hidden in known orbital solutions of eccentric super-Earths and Neptune mass planets. Subject headings: Exoplanets – Orbital dynamics – Planet detection – Doppler method arXiv:0809.1275v2 [astro-ph] 25 Nov 2009 Introduction Most of the +300 exoplanets found to date have been discovered using the Doppler tech- nique, which measures the reflex motion of the host star induced by the planets (Mayor & Queloz 1995; Marcy & Butler 1996). The diverse characteristics of these exoplanets are somewhat surprising. Many of them are similar in mass to Jupiter, but orbit much closer to their 1Carnegie Institution of Washington, Department of Terrestrial Magnetism, 5241 Broad Branch Rd. -
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. -
The ELODIE Survey for Northern Extra-Solar Planets?,??,???
A&A 410, 1039–1049 (2003) Astronomy DOI: 10.1051/0004-6361:20031340 & c ESO 2003 Astrophysics The ELODIE survey for northern extra-solar planets?;??;??? I. Six new extra-solar planet candidates C. Perrier1,J.-P.Sivan2,D.Naef3,J.L.Beuzit1, M. Mayor3,D.Queloz3,andS.Udry3 1 Laboratoire d’Astrophysique de Grenoble, Universit´e J. Fourier, BP 53, 38041 Grenoble, France 2 Observatoire de Haute-Provence, 04870 St-Michel L’Observatoire, France 3 Observatoire de Gen`eve, 51 Ch. des Maillettes, 1290 Sauverny, Switzerland Received 17 July 2002 / Accepted 1 August 2003 Abstract. Precise radial-velocity observations at Haute-Provence Observatory (OHP, France) with the ELODIE echelle spec- trograph have been undertaken since 1994. In addition to several discoveries described elsewhere, including and following that of 51 Peg b, they reveal new sub-stellar companions with essentially moderate to long periods. We report here about such companions orbiting five solar-type stars (HD 8574, HD 23596, HD 33636, HD 50554, HD 106252) and one sub-giant star (HD 190228). The companion of HD 8574 has an intermediate period of 227.55 days and a semi-major axis of 0.77 AU. All other companions have long periods, exceeding 3 years, and consequently their semi-major axes are around or above 2 AU. The detected companions have minimum masses m2 sin i ranging from slightly more than 2 MJup to 10.6 MJup. These additional objects reinforce the conclusion that most planetary companions have masses lower than 5 MJup but with a tail of the mass dis- tribution going up above 15 MJup. -
Extrasolar Planetary Systems
Docent lecture, Ulrike Heiter, 2006-12-04 Extrasolar planetary systems Docent lecture Ulrike Heiter Department of Astronomy and Space Physics, Uppsala University Background image credit: Gemini Observatory, Artwork by Jon Lomberg Outline •Other worlds throughout history •Definition of ”Planet” •Searching for extrasolar planets . Detection methods . Detection history •Census of extrasolar planets . Properties of planets and planet hosts . Comparison to Solar System •Outlook 1 Docent lecture, Ulrike Heiter, 2006-12-04 Other worlds throughout history •300 B.C. – Epicurus ”The number of world-systems is infinite. These include worlds similar to our own and dissimilar ones.” Letter to To Herodotus – epicurus.info •1584 – Giordano Bruno ”Innumerable suns exist; innumerable earths revolve around these suns …” •1750 – Thomas Wright – An original theory or new hypothesis of the universe ”… a Universe of worlds all covered by mountains, lakes, seas, grasses, animals, rivers, rocks, caves, …” Definition of Planet today •Working definition of extrasolar planets of International Astronomical Union (can change in future) •Objects with masses below the limiting mass for thermonuclear fusion of deuterium – currently calculated to be 13 Jupiter masses – that orbit stars or stellar remnants •Minimum mass/size same as that used in our Solar System •Objects with masses above the limiting mass for thermonuclear fusion of deuterium but below the limiting mass for fusion of hydrogen are ”brown dwarfs”. 2 Docent lecture, Ulrike Heiter, 2006-12-04 Planet classification (solar system) Gaseous atmosphere Crust Molecular hydrogen Mantle Metallic hydrogen Outer core Rock/Iron core Inner core •Gas giant planets •Rocky small planets •Composed mainly of •Composed mainly of high- low-density gas density rock and metal (hydrogen, helium) •Low mass (<0.005MJ) •High mass (>0.005MJ) •slow rotation •rapid rotation •no rings and few satellites •rings and many satellites Planet Timing mass Transits Radial Astrometry Imaging Pulsars velocity M. -
From ESPRESSO to PLATO: Detecting and Characterizing Earth-Like Planets in the Presence of Stellar Noise
From ESPRESSO to PLATO: detecting and characterizing Earth-like planets in the presence of stellar noise Tese de Doutouramento Luisa Maria Serrano Departamento de Fisica e Astronomia do Porto, Faculdade de Ciências da Universidade do Porto Orientador: Nuno Cardoso Santos, Co-Orientadora: Susana Cristina Cabral Barros March 2020 Dedication This Ph.D. thesis is the result of 4 years of work, stress, anxiety, but, over all, fun, curiosity and desire of exploring the most hidden scientific discoveries deserved by Astrophysics. Working in Exoplanets was the beginning of the realization of a life-lasting dream, it has allowed me to enter an extremely active and productive group. For this reason my thanks go, first of all, to the ’boss’ and my Ph.D. supervisor, Nuno Santos. He allowed me to be here and introduced me in this world, a distant mirage for the master student from a university where there was no exoplanets thematic line. I also have to thank him for his humanity, not a common quality among professors. The second thank goes to Susana, who was always there for me when I had issues, not necessarily scientific ones. I finally have to thank Mahmoud; heis not listed as supervisor here, but he guided me, teaching me how to do research and giving me precious life lessons, which made me growing. There is also a long series of people I am thankful to, for rendering this years extremely interesting and sustaining me in the deepest moments. My first thought goes to my parents: they were thousands of kilometers far away from me, though they never left me alone and they listened to my complaints, joy, sadness...everything. -
P Lanetary Postc Ards
Suggested Discussion Questions for Planetary PostCards That star is hotter/colder than our Sun. How do you Planetary PostCards think that might affect its planets? Here is where one of the planets orbits that star. What would it be like to live on this planet (or one of its moons)? If Earth was orbiting that star, what might be different? Artist: Lynette Cook 55 Cancri System How big do you suppose this planet is compared to Abbreviations and terms used on PostCards the planets in our Solar System? RA = Right Ascension Do you think we have found all the planets in this Dec = Declination system? mag = apparent visual magnitude AU = Astronomical Unit, the distance between the Earth and Our fastest spacecraft travels 42 miles per second. It the Sun: 93 million miles or 150 million km would take 5,000 years for that spacecraft to go one Light year = The distance light travels in a year. Light travels at light year. How long would it take to reach this star 186,000 miles per second or 300,000 km per second. Light which is ____ light years away? from the Sun takes 8 minutes to reach Earth. Jupiter mass = 1.9 x1027 kg. Jupiter is about 300 times more How different do you think Earth will be in that massive than Earth (approximate difference between a large period of time? bowling ball and a small marble) Temperature of the stars is in degrees Celsius Cepheus Draco Ursa Ursa Minor gamma Cephei 39' º mag: 3.2 mag: Dec: 77 Dec: RA: 23h 39m RA: Ursa MajorUrsa Star: Gamma Cephei Planet: Gamma Cephei b Star’s System Compared to Our Solar System How far in How Hot? light years? °C Neptune 150 7000 Uranus < Sun 100 Saturn Star > 5000 Gamma Cephei b > 50 3000 Jupiter < 39 < Companion Star Sun 1000 Planet (year discovered): b (2002) The brightest star with a planet is Avg Distance From Star: 2 AU (Earth from Sun = 1 AU) a Binary star AND it’s a Red Giant! Orbit: Its small “companion star” gets as 2.5 years close as 12 AU in a 40-year orbit. -
Planetquest Outreach Toolkit Manual and Resources Cd
Outreach ToolKit Manual DISTRIBUTED FOR MEMBERS OF THE NASA NIGHT SKY NETWORK THE NIGHT SKY NETWORK IS SPONSORED AND SUPPORTED BY JPL'S PLANETQUEST PUBLIC ENGAGEMENT PROGRAM. PLANETQUEST IS A PART OF JPL’S NAVIGATOR PROGRAM, WHICH ENCOMPASSES SEVERAL OF NASA'S EXTRA-SOLAR PLANET- FINDING MISSIONS, INCLUDING THE KECK INTERFEROMETER, THE SPACE INTERFEROMETRY MISSION (SIM), THE TERRESTRIAL PLANET FINDER (TPF), THE LARGE BINOCULAR TELESCOPE INTERFEROMETER (LBTI), AND THE MICHELSON SCIENCE CENTER. NASA NIGHT SKY NETWORK: http://nightsky.jpl.nasa.gov/ PLANETQUEST: http://planetquest.jpl.nasa.gov/ Contacts The non-profit Astronomical Society of the Pacific (ASP), one of the nation’s leading organizations devoted to astronomy and space science education, is managing the Night Sky Network in cooperation with JPL. Learn more about the ASP at http://www.astrosociety.org. For support contact: Astronomical Society of the Pacific (ASP) 390 Ashton Avenue San Francisco, CA 94112 415-337-1100 ext. 116 [email protected] Copyright © 2004 NASA/JPL and Astronomical Society of the Pacific. Copies of this manual and documents may be made for educational and public outreach purposes only and are to be supplied at no charge to participants. Any other use is not permitted. CREDITS: All photos and images in the ToolKit Manual unless otherwise noted are provided courtesy of Marni Berendsen and Rich Berendsen. Your Club’s Membership in the NASA Night Sky Network Welcome to the NASA Night Sky Network! Your membership in the Night Sky Network will provide many opportunities for your club to expand its public education and outreach. Your club has at least two members who are the Night Sky Network Club Coordinators. -
Post-Main-Sequence Planetary System Evolution Rsos.Royalsocietypublishing.Org Dimitri Veras
Post-main-sequence planetary system evolution rsos.royalsocietypublishing.org Dimitri Veras Department of Physics, University of Warwick, Coventry CV4 7AL, UK Review The fates of planetary systems provide unassailable insights Cite this article: Veras D. 2016 into their formation and represent rich cross-disciplinary Post-main-sequence planetary system dynamical laboratories. Mounting observations of post-main- evolution. R. Soc. open sci. 3: 150571. sequence planetary systems necessitate a complementary level http://dx.doi.org/10.1098/rsos.150571 of theoretical scrutiny. Here, I review the diverse dynamical processes which affect planets, asteroids, comets and pebbles as their parent stars evolve into giant branch, white dwarf and neutron stars. This reference provides a foundation for the Received: 23 October 2015 interpretation and modelling of currently known systems and Accepted: 20 January 2016 upcoming discoveries. 1. Introduction Subject Category: Decades of unsuccessful attempts to find planets around other Astronomy Sun-like stars preceded the unexpected 1992 discovery of planetary bodies orbiting a pulsar [1,2]. The three planets around Subject Areas: the millisecond pulsar PSR B1257+12 were the first confidently extrasolar planets/astrophysics/solar system reported extrasolar planets to withstand enduring scrutiny due to their well-constrained masses and orbits. However, a retrospective Keywords: historical analysis reveals even more surprises. We now know that dynamics, white dwarfs, giant branch stars, the eponymous celestial body that Adriaan van Maanen observed pulsars, asteroids, formation in the late 1910s [3,4]isanisolatedwhitedwarf(WD)witha metal-enriched atmosphere: direct evidence for the accretion of planetary remnants. These pioneering discoveries of planetary material around Author for correspondence: or in post-main-sequence (post-MS) stars, although exciting, Dimitri Veras represented a poor harbinger for how the field of exoplanetary e-mail: [email protected] science has since matured. -
Les Planetes Extrasolaires
QUASAR 95 LES PLANETES EXTRASOLAIRES La recherche de planètes en dehors du système solaire (exoplanètes) est un des sujets les plus importants de cette fin de siècle. La discipline est très récente et mérite une extrême prudence en ce qui concerne les affirmations. Les vérités d'aujourd'hui ne sont pas forcément celles de demain. Cependant, quelques découvertes font actuellement l'unanimité des chercheurs. Le sujet ouvre des voies de recherche insoupçonnées il y a peu de temps, et une compétition acharnée entre les équipes de chercheurs, puisqu'il touche au domaine de la vie extraterrestre. I - HISTORIQUE DES DECOUVERTES Depuis environ 20 ans, les instruments à notre disposition s'approchent de la sensibilité nécessaire à la découverte d'exoplanètes. La recherche est parsemée d'échecs, parmi les plus retentissants : - L'étoile de Barnard, L'étoile de Van Biesbroek, 61 Cigny, sont en fait des artefacts ou des erreurs de mesure. - Gliese 229 est une naine brune et non pas une planète. Cette naine a été depuis photographiée par Hubble. C'est la première découverte incontestable de naine brune. - La première pseudo-découverte d'une planète autour d'un pulsar était due à un mauvais calcul de la correction du mouvement de la Terre autour du Soleil. Une demi-douzaine d'équipes travaillait (avant la première vraie découverte) sur le sujet, et entre autres : - Gordon Walker et Bruce Campbell ont étudié 45 étoiles au 3,6 m d'Hawaii (USA). - David Lathan a travaillé 15 ans sur l'étoile HD 114762 (USA). - Michel Major et Didier Queloz, de l'observatoire de Genève (Suisse) ont étudié 142 étoiles depuis avril 94, à l'OHP, en France.