Where Are the Distant Worlds? Star Maps
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High Precision Photometry of Transiting Exoplanets
McNair Scholars Research Journal Volume 3 Article 3 2016 High Precision Photometry of Transiting Exoplanets Maurice Wilson Embry-Riddle Aeronautical University and Harvard-Smithsonian Center for Astrophysics Jason Eastman Harvard-Smithsonian Center for Astrophysics John Johnson Harvard-Smithsonian Center for Astrophysics Follow this and additional works at: https://commons.erau.edu/mcnair Recommended Citation Wilson, Maurice; Eastman, Jason; and Johnson, John (2016) "High Precision Photometry of Transiting Exoplanets," McNair Scholars Research Journal: Vol. 3 , Article 3. Available at: https://commons.erau.edu/mcnair/vol3/iss1/3 This Article is brought to you for free and open access by the Journals at Scholarly Commons. It has been accepted for inclusion in McNair Scholars Research Journal by an authorized administrator of Scholarly Commons. For more information, please contact [email protected]. Wilson et al.: High Precision Photometry of Transiting Exoplanets High Precision Photometry of Transiting Exoplanets Maurice Wilson1,2, Jason Eastman2, and John Johnson2 1Embry-Riddle Aeronautical University 2Harvard-Smithsonian Center for Astrophysics In order to increase the rate of finding, confirming, and characterizing Earth-like exoplanets, the MINiature Exoplanet Radial Velocity Array (MINERVA) was recently built with the purpose of obtaining the spectroscopic and photometric precision necessary for these tasks. Achieving the satisfactory photometric precision is the primary focus of this work. This is done with the four telescopes of MINERVA and the defocusing technique. The satisfactory photometric precision derives from the defocusing technique. The use of MINERVA’s four telescopes benefits the relative photometry that must be conducted. Typically, it is difficult to find satisfactory comparison stars within a telescope’s field of view when the primary target is very bright. -
THUBAN the Star Thuban in the Constellation Draco (The Dragon) Was the North Pole Star Some 5,000 Years Ago, When the Egyptians Were Building the Pyramids
STAR OF THE WEEK: THUBAN The star Thuban in the constellation Draco (the Dragon) was the North Pole Star some 5,000 years ago, when the Egyptians were building the pyramids. Thuban is not a particularly bright star. At magnitude 3.7 and known as alpha draconis it is not even the brightest star in its constellation. What is Thuban’s connection with the pyramids of Egypt? Among the many mysteries surrounding Egypt’s pyramids are the so-called “air shafts” in the Great Pyramid of Giza. These narrow passageways were once thought to serve for ventilation as the The Great Pyramid of Giza, an enduring monument of ancient pyramids were being built. In the 1960s, though, Egypt. Egyptologists believe that it was built as a tomb for fourth dynasty Egyptian Pharaoh Khufu around 2560 BC the air shafts were recognized as being aligned with stars or areas of sky as the sky appeared for the pyramids’ builders 5,000 years ago. To this day, the purpose of all these passageways inside the Great Pyramid isn’t clear, although some might have been connected to rituals associated with the king’s ascension to the heavens. Whatever their purpose, the Great Pyramid of Giza reveals that its builders knew the starry skies intimately. They surely knew Thuban was their Pole Star, the point around which the heavens appeared to turn. Various sources claim that Thuban almost exactly pinpointed the position of the north celestial pole in the This diagram shows the so-called air shafts in the Great year 2787 B.C. -
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. -
New Atmospheric Parameters and Spectral Interpolator for the MILES Cool Stars Kaushal Sharma1,2,3, Philippe Prugniel1,2, and Harinder P
A&A 585, A64 (2016) Astronomy DOI: 10.1051/0004-6361/201526111 & c ESO 2015 Astrophysics New atmospheric parameters and spectral interpolator for the MILES cool stars Kaushal Sharma1,2,3, Philippe Prugniel1,2, and Harinder P. Singh3,1,2 1 Université de Lyon, Université Lyon 1, 69622 Villeurbanne, France e-mail: [email protected] 2 CRAL, Observatoire de Lyon, CNRS UMR 5574, 69561 Saint-Genis Laval, France 3 Department of Physics and Astrophysics, University of Delhi, 110007 Delhi, India e-mail: [kaushal;hpsingh]@physics.du.ac.in Received 17 March 2015 / Accepted 18 October 2015 ABSTRACT Context. The full spectrum fitting of stellar spectra against a library of empirical spectra is a well-established approach to measure the atmospheric parameters of FGK stars with a high internal consistency. Extending it towards cooler stars still remains a challenge. Aims. We address this question by improving the interpolator of the Medium-resolution INT Library of Empirical Spectra (MILES) library in the low effective temperature regime (Teff < 4800 K), and we refine the determination of the parameters of the cool MILES stars. Methods. We use the ULySS package to determine the atmospheric parameters (Teff,logg and [Fe/H]), and measure the biases of the results with respect to our updated compilation of parameters calibrated against theoretical spectra. After correcting some systematic effects, we compute a new interpolator that we finally use to redetermine the atmospheric parameters homogeneously and assess the biases. Results. Based on an updated literature compilation, we determine Teff in a more accurate and unbiased manner compared to those determined with the original interpolator. -
100 Closest Stars Designation R.A
100 closest stars Designation R.A. Dec. Mag. Common Name 1 Gliese+Jahreis 551 14h30m –62°40’ 11.09 Proxima Centauri Gliese+Jahreis 559 14h40m –60°50’ 0.01, 1.34 Alpha Centauri A,B 2 Gliese+Jahreis 699 17h58m 4°42’ 9.53 Barnard’s Star 3 Gliese+Jahreis 406 10h56m 7°01’ 13.44 Wolf 359 4 Gliese+Jahreis 411 11h03m 35°58’ 7.47 Lalande 21185 5 Gliese+Jahreis 244 6h45m –16°49’ -1.43, 8.44 Sirius A,B 6 Gliese+Jahreis 65 1h39m –17°57’ 12.54, 12.99 BL Ceti, UV Ceti 7 Gliese+Jahreis 729 18h50m –23°50’ 10.43 Ross 154 8 Gliese+Jahreis 905 23h45m 44°11’ 12.29 Ross 248 9 Gliese+Jahreis 144 3h33m –9°28’ 3.73 Epsilon Eridani 10 Gliese+Jahreis 887 23h06m –35°51’ 7.34 Lacaille 9352 11 Gliese+Jahreis 447 11h48m 0°48’ 11.13 Ross 128 12 Gliese+Jahreis 866 22h39m –15°18’ 13.33, 13.27, 14.03 EZ Aquarii A,B,C 13 Gliese+Jahreis 280 7h39m 5°14’ 10.7 Procyon A,B 14 Gliese+Jahreis 820 21h07m 38°45’ 5.21, 6.03 61 Cygni A,B 15 Gliese+Jahreis 725 18h43m 59°38’ 8.90, 9.69 16 Gliese+Jahreis 15 0h18m 44°01’ 8.08, 11.06 GX Andromedae, GQ Andromedae 17 Gliese+Jahreis 845 22h03m –56°47’ 4.69 Epsilon Indi A,B,C 18 Gliese+Jahreis 1111 8h30m 26°47’ 14.78 DX Cancri 19 Gliese+Jahreis 71 1h44m –15°56’ 3.49 Tau Ceti 20 Gliese+Jahreis 1061 3h36m –44°31’ 13.09 21 Gliese+Jahreis 54.1 1h13m –17°00’ 12.02 YZ Ceti 22 Gliese+Jahreis 273 7h27m 5°14’ 9.86 Luyten’s Star 23 SO 0253+1652 2h53m 16°53’ 15.14 24 SCR 1845-6357 18h45m –63°58’ 17.40J 25 Gliese+Jahreis 191 5h12m –45°01’ 8.84 Kapteyn’s Star 26 Gliese+Jahreis 825 21h17m –38°52’ 6.67 AX Microscopii 27 Gliese+Jahreis 860 22h28m 57°42’ 9.79, -
Download the Search for New Planets
“VITAL ARTICLES ON SCIENCE/CREATION” September 1999 Impact #315 THE SEARCH FOR NEW PLANETS by Don DeYoung, Ph.D.* The nine solar system planets, from Mercury to Pluto, have been much-studied targets of the space age. In general, a planet is any massive object which orbits a star, in our case, the Sun. Some have questioned the status of Pluto, mainly because of its small size, but it remains a full-fledged planet. There is little evidence for additional solar planets beyond Pluto. Instead, attention has turned to extrasolar planets which may circle other stars. Intense competition has arisen among astronomers to detect such objects. Success insures media attention, journal publication, and continued research funding. The Interest in Planets Just one word explains the intense interest in new planets—life. Many scientists are convinced that we are not alone in space. Since life evolved on Earth, it must likewise have happened elsewhere, either on planets or their moons. The naïve assumption is that life will arise if we “just add water”: Earth-like planet + water → spontaneous life This equation is falsified by over a century of biological research showing the deep complexity of life. Scarcely is there a fact more certain than that matter does not spring into life on its own. Drake Equation Astronomer Frank Drake pioneered the Search for ExtraTerrestrial Intelligence project, or SETI, in the 1960s. He also attempted to calculate the total number of planets with life. The Drake Equation in simplified form is: Total livable Probability of Planets with planets x evolution = evolved life *Don DeYoung, Ph.D., is an Adjunct Professor of Physics at ICR. -
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. -
Wynyard Planetarium & Observatory a Autumn Observing Notes
Wynyard Planetarium & Observatory A Autumn Observing Notes Wynyard Planetarium & Observatory PUBLIC OBSERVING – Autumn Tour of the Sky with the Naked Eye CASSIOPEIA Look for the ‘W’ 4 shape 3 Polaris URSA MINOR Notice how the constellations swing around Polaris during the night Pherkad Kochab Is Kochab orange compared 2 to Polaris? Pointers Is Dubhe Dubhe yellowish compared to Merak? 1 Merak THE PLOUGH Figure 1: Sketch of the northern sky in autumn. © Rob Peeling, CaDAS, 2007 version 1.2 Wynyard Planetarium & Observatory PUBLIC OBSERVING – Autumn North 1. On leaving the planetarium, turn around and look northwards over the roof of the building. Close to the horizon is a group of stars like the outline of a saucepan with the handle stretching to your left. This is the Plough (also called the Big Dipper) and is part of the constellation Ursa Major, the Great Bear. The two right-hand stars are called the Pointers. Can you tell that the higher of the two, Dubhe is slightly yellowish compared to the lower, Merak? Check with binoculars. Not all stars are white. The colour shows that Dubhe is cooler than Merak in the same way that red-hot is cooler than white- hot. 2. Use the Pointers to guide you upwards to the next bright star. This is Polaris, the Pole (or North) Star. Note that it is not the brightest star in the sky, a common misconception. Below and to the left are two prominent but fainter stars. These are Kochab and Pherkad, the Guardians of the Pole. Look carefully and you will notice that Kochab is slightly orange when compared to Polaris. -
400 Years of Women in Science Review by Andrew W
National Capital Astronomers, Inc. Phone: 301/565-3709 Volume 56, Number I September, 1997 ISSN 0898-7548 A biography Alan P. Boss is a staff member at the Carnegie Institution of Washington's Department of Terrestrial Magnetism Abstract highly eccentric orbits are a clue to their (DTM) in northwest Washington, D.C. Searches for extrasolar planets and origin as stars rather than as planets. Boss received his Ph.D. in physics from brown dwarfs have a long and dismal Giant planets must form in the relatively the University of California, Santa Bar- history. HowevAr r"-of discoveries cool, outer regions of protoplanetary bara, in 1979. He spent two years as a have . the advent of an era of disks, which is why the discovery of postdoctoral fellow at NASA's Ames ~ ..----tfi'SCovery of extrasolar planetary sys- several giant planets with circular orbits Reseach Center in California before tems. The newly discovered objects ap- very close to their central stars was a joining the staff ofDTM in 1981. Boss's pear to be a mixture of gas giant planets, shock to theorists. These discoveries research focuses on using three dimen- similar to Jupiter, and brown dwarf have forced theorists to accept the fact sional hydrodynamics codes to model stars, elusive objects that have long been that some planets must migrate inwards the formation of stars and planetary sys- hypothesized to exist but never seen from their place of birth toward their tems. He has been helping NASA plan before. Brown dwarf stars are interme- central star. This inward migration ap- its search for extrasolar planets ever diate in mass between giant planets and pears to have been negligible for our since 1988, and continues to be acti ve in the lowest mass stars that can burn hy- solar system, however. -
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. -
Space Missions for Exoplanet
Space missions for exoplanet January 3, 2020 Source: The Hindu Manifest pedagogy: As a part of science & technology and geography, questions related to space have been asked both at prelims and mains stage. Finding life in other celestial bodies had always been a human curiosity. Origin of the solar system, exoplanets as prospective resources zone, finding life etc are key objectives of NASA and other space programs. In news: European Space Agency (ESA) has launched CHEOPS exoplanet mission Placing it in syllabus: Exoplanet space missions Static dimensions: What are exoplanets? Current dimensions: Exoplanet missions by NASA Exoplanet missions by ESA and CHEOPS mission Content: What are Exoplanets? The worlds orbiting other stars are called “exoplanets”. They vary in sizes, from gas giants larger than Jupiter to small, rocky planets about as big around as Earth. They can be hot enough to boil metal or locked in deep freeze. They can orbit two suns at once. Some exoplanets are sunless, wandering through the galaxy in permanent darkness. The first exoplanet invented was 51 Pegasi b, a “hot Jupiter” in 1995 which is 50 light-years away that is locked in a four-day orbit around its star. ((The discoverers Didier Queloz and Michel Mayor of 51 Pegasi b shared the 2019 Nobel Prize in Physics for their breakthrough finding)). And a system of three “pulsar planets” had been detected, beginning in 1992. The circumstellar habitable zone (CHZ) also called the Goldilocks zone is the range of orbits around a star within which a planetary surface can support liquid water given sufficient atmospheric pressure. -
Correlations Between the Stellar, Planetary, and Debris Components of Exoplanet Systems Observed by Herschel⋆
A&A 565, A15 (2014) Astronomy DOI: 10.1051/0004-6361/201323058 & c ESO 2014 Astrophysics Correlations between the stellar, planetary, and debris components of exoplanet systems observed by Herschel J. P. Marshall1,2, A. Moro-Martín3,4, C. Eiroa1, G. Kennedy5,A.Mora6, B. Sibthorpe7, J.-F. Lestrade8, J. Maldonado1,9, J. Sanz-Forcada10,M.C.Wyatt5,B.Matthews11,12,J.Horner2,13,14, B. Montesinos10,G.Bryden15, C. del Burgo16,J.S.Greaves17,R.J.Ivison18,19, G. Meeus1, G. Olofsson20, G. L. Pilbratt21, and G. J. White22,23 (Affiliations can be found after the references) Received 15 November 2013 / Accepted 6 March 2014 ABSTRACT Context. Stars form surrounded by gas- and dust-rich protoplanetary discs. Generally, these discs dissipate over a few (3–10) Myr, leaving a faint tenuous debris disc composed of second-generation dust produced by the attrition of larger bodies formed in the protoplanetary disc. Giant planets detected in radial velocity and transit surveys of main-sequence stars also form within the protoplanetary disc, whilst super-Earths now detectable may form once the gas has dissipated. Our own solar system, with its eight planets and two debris belts, is a prime example of an end state of this process. Aims. The Herschel DEBRIS, DUNES, and GT programmes observed 37 exoplanet host stars within 25 pc at 70, 100, and 160 μm with the sensitiv- ity to detect far-infrared excess emission at flux density levels only an order of magnitude greater than that of the solar system’s Edgeworth-Kuiper belt. Here we present an analysis of that sample, using it to more accurately determine the (possible) level of dust emission from these exoplanet host stars and thereafter determine the links between the various components of these exoplanetary systems through statistical analysis.