Guidestar's Monthly Calendar of Producing Planetary Nebulae
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Lecture-29 (PDF)
Life in the Universe Orin Harris and Greg Anderson Department of Physics & Astronomy Northeastern Illinois University Spring 2021 c 2012-2021 G. Anderson., O. Harris Universe: Past, Present & Future – slide 1 / 95 Overview Dating Rocks Life on Earth How Did Life Arise? Life in the Solar System Life Around Other Stars Interstellar Travel SETI Review c 2012-2021 G. Anderson., O. Harris Universe: Past, Present & Future – slide 2 / 95 Dating Rocks Zircon Dating Sedimentary Grand Canyon Life on Earth How Did Life Arise? Life in the Solar System Life Around Dating Rocks Other Stars Interstellar Travel SETI Review c 2012-2021 G. Anderson., O. Harris Universe: Past, Present & Future – slide 3 / 95 Zircon Dating Zircon, (ZrSiO4), minerals incorporate trace amounts of uranium but reject lead. Naturally occuring uranium: • U-238: 99.27% • U-235: 0.72% Decay chains: • 238U −→ 206Pb, τ =4.47 Gyrs. • 235U −→ 207Pb, τ = 704 Myrs. 1956, Clair Camron Patterson dated the Canyon Diablo meteorite: τ =4.55 Gyrs. c 2012-2021 G. Anderson., O. Harris Universe: Past, Present & Future – slide 4 / 95 Dating Sedimentary Rocks • Relative ages: Deeper layers were deposited earlier • Absolute ages: Decay of radioactive isotopes old (deposited last) oldest (depositedolder first) c 2012-2021 G. Anderson., O. Harris Universe: Past, Present & Future – slide 5 / 95 Grand Canyon: Earth History from 200 million - 2 billion yrs ago. Dating Rocks Life on Earth Earth History Timeline Late Heavy Bombardment Hadean Shark Bay Stromatolites Cyanobacteria Q: Earliest Fossils? Life on Earth O2 History Q: Life on Earth How Did Life Arise? Life in the Solar System Life Around Other Stars Interstellar Travel SETI Review c 2012-2021 G. -
Biosignatures Search in Habitable Planets
galaxies Review Biosignatures Search in Habitable Planets Riccardo Claudi 1,* and Eleonora Alei 1,2 1 INAF-Astronomical Observatory of Padova, Vicolo Osservatorio, 5, 35122 Padova, Italy 2 Physics and Astronomy Department, Padova University, 35131 Padova, Italy * Correspondence: [email protected] Received: 2 August 2019; Accepted: 25 September 2019; Published: 29 September 2019 Abstract: The search for life has had a new enthusiastic restart in the last two decades thanks to the large number of new worlds discovered. The about 4100 exoplanets found so far, show a large diversity of planets, from hot giants to rocky planets orbiting small and cold stars. Most of them are very different from those of the Solar System and one of the striking case is that of the super-Earths, rocky planets with masses ranging between 1 and 10 M⊕ with dimensions up to twice those of Earth. In the right environment, these planets could be the cradle of alien life that could modify the chemical composition of their atmospheres. So, the search for life signatures requires as the first step the knowledge of planet atmospheres, the main objective of future exoplanetary space explorations. Indeed, the quest for the determination of the chemical composition of those planetary atmospheres rises also more general interest than that given by the mere directory of the atmospheric compounds. It opens out to the more general speculation on what such detection might tell us about the presence of life on those planets. As, for now, we have only one example of life in the universe, we are bound to study terrestrial organisms to assess possibilities of life on other planets and guide our search for possible extinct or extant life on other planetary bodies. -
Herschel PACS and SPIRE Imaging of CW Leonis*
A&A 518, L141 (2010) Astronomy DOI: 10.1051/0004-6361/201014658 & c ESO 2010 Astrophysics Herschel: the first science highlights Special feature Letter to the Editor Herschel PACS and SPIRE imaging of CW Leonis D. Ladjal1,M.J.Barlow2,M.A.T.Groenewegen3,T.Ueta4,J.A.D.L.Blommaert1, M. Cohen5, L. Decin1,6, W. De Meester1,K.Exter1,W.K.Gear7,H.L.Gomez7,P.C.Hargrave7, R. Huygen1,R.J.Ivison8, C. Jean1, F. Kerschbaum9,S.J.Leeks10,T.L.Lim10, G. Olofsson11, E. Polehampton10,12,T.Posch9,S.Regibo1,P.Royer1, B. Sibthorpe8,B.M.Swinyard10, B. Vandenbussche1 , C. Waelkens1, and R. Wesson2 1 Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium e-mail: [email protected] 2 Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK 3 Koninklijke Sterrenwacht van België, Ringlaan 3, 1180 Brussels, Belgium 4 Dept. of Physics and Astronomy, University of Denver, Mail Stop 6900, Denver, CO 80208, USA 5 Radio Astronomy Laboratory, University of California at Berkeley, CA 94720, USA 6 Sterrenkundig Instituut Anton Pannekoek, Universiteit van Amsterdam, Kruislaan 403, 1098 Amsterdam, The Netherlands 7 School of Physics and Astronomy, Cardiff University, 5 The Parade, Cardiff, Wales CF24 3YB, UK 8 UK Astronomy Technology Centre, Royal Observatory Edinburgh, Blackford Hill, Edinburgh EH9 3HJ, UK 9 University Vienna, Department of Astronomy, Türkenschanzstrasse 17, 1180 Wien, Austria 10 Space Science and Technology Department, Rutherford Appleton Laboratory, Oxfordshire, OX11 0QX, UK 11 Dept. of Astronomy, Stockholm University, AlbaNova University Center, Roslagstullsbacken 21, 10691 Stockholm, Sweden 12 Department of Physics, University of Lethbridge, Alberta, Canada Received 31 March 2010 / Accepted 15 April 2010 ABSTRACT Herschel PACS and SPIRE images have been obtained over a 30 × 30 area around the well-known carbon star CW Leo (IRC +10 216). -
Gillian R. Knapp - Curriculum Vitae Born: Widnes, United Kingdom, October 10, 1944
Gillian R. Knapp - Curriculum Vitae Born: Widnes, United Kingdom, October 10, 1944. B.Sc. (Hons.) Physics, University of Edinburgh, 1966. Ph.D. Astronomy, University of Maryland, 1972. Professional Societies American Astronomical Society, Royal Astronomical Society, International Union of Radio Science, International Astronomical Union Positions held Teaching associate, University of Maryland, l971-3. Research fellow, Senior Research Fellow, Research Associate, California Institute of Technology, 1974-9. Research astronomer, Princeton University, 1980-4. Associate Professor, Professor, Princeton University, 1984- Visiting Assistant Professor, University of Washington, spring 1979. Visiting Associate Professor, UCLA, spring 1980. Visiting Fellow, University of Groningen, The Netherlands, summer 1981. Visiting astronomer, Bell Laboratories, 1980-92. Visiting professor, Institute for Astronomy, University of Hawaii, Fall 1989 Awards Tinsley Centennial Professor, University of Texas, Fall 1985. Distinguished Alumnus Award, University of Maryland, 2003 Leadership Alliance Mentorship Award, 2007 Current and Recent National/ International Committees Caltech Submillimeter Observatory Director’s Advisory Committee: NAIC Arecibo Advi- sory Committee: Spitzer Science Center Users’ Committee: NAIC Arecibo Large Projects Oversight Committee: Review Board, DARK Cosmology Institute Current and Recent Princeton University and Department Activities EEEO officer, Coordinator for Undergraduate Summer Research, and Director of Graduate Studies, Astrophysics: -
Fermi's Paradox Is a Daunting Problem – Under Whatever Label
Fermi's Paradox Is a Daunting Problem – Under Whatever Label Milan M. Dirkovid1 Astronomical Observatory of Belgrade, Volgina 7, 11000 Belgrade, Serbia 1. Introduction Gray (2015) argued that Fermi's paradox (FP) is a misnomer, and it is not a valid paradox. Gray also speculated that the argument was misattributed to Fermi, whose lunchtime remarks did not pertain to the existence of extraterrestrial intelligence, but to the feasibility of interstellar travel. Instead, the paradox is ascribed to Hart and Tipler, and it is further suggested that the paradox is not a “real” problem or research subject and should not be used in debates about SETI projects. The arguments given are unpersuasive, ahistorical, and, in at least one instance, clearly hinge on literalistic and uncharitable reading of evidence. Instead, I argue the following three points: (i) Contrary to Gray’s assertion, the historical issue of naming of ideas or concepts is completely divorced from their epistemic status. (ii) FP is easily and smoothly generalized into the “Great Silence” paradox, so it makes no sense either theoretically or empirically to separate the two. (iii) In sharp contrast to the main implication of Gray’s paper, FP has become more aggravated lately due to advances in astrobiology. Research that deals with FP has greatly expanded in recent years on both a theoretical and observational stage (Davies 2010, 2012; Vukotid and Dirkovid 2012; Barlow 2013; Hair and Hedman 2013; Davies and Wagner 2013; Armstrong and Sandberg 2013; Lampton 2013; Cartin 2014; Nunn, Guy, and Bell 2014; Wright et al. 2014; Spivey 2015; Griffith et al. -
Stars and Their Spectra: an Introduction to the Spectral Sequence Second Edition James B
Cambridge University Press 978-0-521-89954-3 - Stars and Their Spectra: An Introduction to the Spectral Sequence Second Edition James B. Kaler Index More information Star index Stars are arranged by the Latin genitive of their constellation of residence, with other star names interspersed alphabetically. Within a constellation, Bayer Greek letters are given first, followed by Roman letters, Flamsteed numbers, variable stars arranged in traditional order (see Section 1.11), and then other names that take on genitive form. Stellar spectra are indicated by an asterisk. The best-known proper names have priority over their Greek-letter names. Spectra of the Sun and of nebulae are included as well. Abell 21 nucleus, see a Aurigae, see Capella Abell 78 nucleus, 327* ε Aurigae, 178, 186 Achernar, 9, 243, 264, 274 z Aurigae, 177, 186 Acrux, see Alpha Crucis Z Aurigae, 186, 269* Adhara, see Epsilon Canis Majoris AB Aurigae, 255 Albireo, 26 Alcor, 26, 177, 241, 243, 272* Barnard’s Star, 129–130, 131 Aldebaran, 9, 27, 80*, 163, 165 Betelgeuse, 2, 9, 16, 18, 20, 73, 74*, 79, Algol, 20, 26, 176–177, 271*, 333, 366 80*, 88, 104–105, 106*, 110*, 113, Altair, 9, 236, 241, 250 115, 118, 122, 187, 216, 264 a Andromedae, 273, 273* image of, 114 b Andromedae, 164 BDþ284211, 285* g Andromedae, 26 Bl 253* u Andromedae A, 218* a Boo¨tis, see Arcturus u Andromedae B, 109* g Boo¨tis, 243 Z Andromedae, 337 Z Boo¨tis, 185 Antares, 10, 73, 104–105, 113, 115, 118, l Boo¨tis, 254, 280, 314 122, 174* s Boo¨tis, 218* 53 Aquarii A, 195 53 Aquarii B, 195 T Camelopardalis, -
Arxiv:1908.02683V1 [Astro-Ph.IM] 31 Jul 2019
Draft version August 8, 2019 Typeset using LATEX default style in AASTeX62 Nine Axes of Merit for Technosignature Searches Sofia Z. Sheikh1 1Department of Astronomy & Astrophysics and Center for Exoplanets and Habitable Worlds 525 Davey Laboratory, The Pennsylvania State University, University Park, PA, 16802, USA ABSTRACT The diverse methodologies and myriad orthogonal proposals for the best technosignatures to search for in SETI can make it difficult to develop an effective and balanced search strategy, especially from a funding perspective. Here I propose a framework to compare the relative advantages and disadvantages of various proposed technosignatures based on nine \axes of merit". This framework was first developed at the NASA Technosignatures Workshop in Houston in 2018 and published in that report. I give the definition and rationale behind the nine axes as well as the history of each axis in the SETI and technosignature literature. These axes are then applied to three example classes of technosignature searches as an illustration of their use. An open-source software tool is available to allow technosignature researchers to make their own version of the figure. Keywords: extraterrestrial intelligence 1. INTRODUCTION Proposed searches for technosignatures range from radio wavelengths to gamma rays, take advantage of almost every astronomical dataset, and use interdisciplinary methodologies in such a way that comparing the merits of two dissimilar searches, even if they're ostensibly in the same field, can be an extremely difficult task. Each SETI practitioner has a different answer for the best strategy to find ETI, often in her own wavelength. Much of the SETI literature engages in promoting the values of a particular search strategy. -
Orbital Elements of Double Stars
Orbital elements of double stars: ADS 1548 Marco Scardia, Jean-Louis Prieur, Luigi Pansecchi, Robert Argyle, Josefina Ling, Eric Aristidi, Alessio Zanutta, Lyu Abe, Philippe Bendjoya, Jean-Pierre Rivet, et al. To cite this version: Marco Scardia, Jean-Louis Prieur, Luigi Pansecchi, Robert Argyle, Josefina Ling, et al.. Orbital elements of double stars: ADS 1548. 2018, pp.1. hal-02357208 HAL Id: hal-02357208 https://hal.archives-ouvertes.fr/hal-02357208 Submitted on 23 Nov 2019 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. INTERNATIONAL ASTRONOMICAL UNION COMMISSION G1 (BINARY AND MULTIPLE STAR SYSTEMS) DOUBLE STARS INFORMATION CIRCULAR No. 194 (FEBRUARY 2018) NEW ORBITS ADS Name P T e Ω(2000) 2018 Author(s) α2000δ n a i ! Last ob. 2019 1548 A 819 AB 135y4 2011.06 0.548 153◦8 39◦7 000161 SCARDIA 01570+3101 2◦6587 000424 50◦5 189◦7 2017.833 49.4 0.163 et al. (*) - HDS 333 49.54 1981.14 0.60 252.6 253.8 0.542 TOKOVININ 02332-5156 7.2665 0.413 57.4 150.9 2018.073 255.7 0.519 - COU 691 61.76 1964.53 0.059 68.6 276.2 0.109 DOCOBO 03423+3141 5.8290 0.160 -
Week 5: January 26-February 1, 2020
5# Ice & Stone 2020 Week 5: January 26-February 1, 2020 Presented by The Earthrise Institute About Ice And Stone 2020 It is my pleasure to welcome all educators, students, topics include: main-belt asteroids, near-Earth asteroids, and anybody else who might be interested, to Ice and “Great Comets,” spacecraft visits (both past and Stone 2020. This is an educational package I have put future), meteorites, and “small bodies” in popular together to cover the so-called “small bodies” of the literature and music. solar system, which in general means asteroids and comets, although this also includes the small moons of Throughout 2020 there will be various comets that are the various planets as well as meteors, meteorites, and visible in our skies and various asteroids passing by Earth interplanetary dust. Although these objects may be -- some of which are already known, some of which “small” compared to the planets of our solar system, will be discovered “in the act” -- and there will also be they are nevertheless of high interest and importance various asteroids of the main asteroid belt that are visible for several reasons, including: as well as “occultations” of stars by various asteroids visible from certain locations on Earth’s surface. Ice a) they are believed to be the “leftovers” from the and Stone 2020 will make note of these occasions and formation of the solar system, so studying them provides appearances as they take place. The “Comet Resource valuable insights into our origins, including Earth and of Center” at the Earthrise web site contains information life on Earth, including ourselves; about the brighter comets that are visible in the sky at any given time and, for those who are interested, I will b) we have learned that this process isn’t over yet, and also occasionally share information about the goings-on that there are still objects out there that can impact in my life as I observe these comets. -
Searches for Life and Intelligence Beyond Earth
Technologies of Perception: Searches for Life and Intelligence Beyond Earth by Claire Isabel Webb Bachelor of Arts, cum laude Vassar College, 2010 Submitted to the Program in Science, Technology and Society in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in History, Anthropology, and Science, Technology and Society at the Massachusetts Institute of Technology September 2020 © 2020 Claire Isabel Webb. All Rights Reserved. The author hereby grants to MIT permission to reproduce and distribute publicly paper and electronic copies of this thesis document in whole or in part in any medium now known or hereafter created. Signature of Author: _____________________________________________________________ History, Anthropology, and Science, Technology and Society August 24, 2020 Certified by: ___________________________________________________________________ David Kaiser Germeshausen Professor of the History of Science (STS) Professor of Physics Thesis Supervisor Certified by: ___________________________________________________________________ Stefan Helmreich Elting E. Morison Professor of Anthropology Thesis Committee Member Certified by: ___________________________________________________________________ Sally Haslanger Ford Professor of Philosophy and Women’s and Gender Studies Thesis Committee Member Accepted by: ___________________________________________________________________ Graham Jones Associate Professor of Anthropology Director of Graduate Studies, History, Anthropology, and STS Accepted by: ___________________________________________________________________ -
Arxiv:2107.07283V3 [Astro-Ph.IM] 27 Jul 2021
Draft version July 28, 2021 Typeset using LATEX default style in AASTeX63 Strategies and Advice for the Search for Extraterrestrial Intelligence Jason T. Wright 1, 2, 3 1Penn State Extraterrestrial Intelligence Center, 525 Davey Laboratory, The Pennsylvania State University, University Park, PA, 16802, USA 2Department of Astronomy & Astrophysics, 525 Davey Laboratory, The Pennsylvania State University, University Park, PA, 16802, USA 3Center for Exoplanets and Habitable Worlds, 525 Davey Laboratory, The Pennsylvania State University, University Park, PA, 16802, USA ABSTRACT As a guide for astronomers new to the field of technosignature search (i.e. SETI), I present an overview of some of its observational and theoretical approaches. I review some of the various observational search strategies for SETI, focusing not on the variety of technosignatures that have been proposed or which are most likely to be found, but on the underlying philosophies that motivate searches for them. I cover passive versus active searches, ambiguous versus dispositive kinds of technosignatures, com- mensal or archival searches versus dedicated ones, communicative signals versus \artifacts", \ac- tive" versus derelict technologies, searches for beacons versus eavesdropping, and model-based versus anomaly-based searches. I also attempt to roughly map the landscape of technosignatures by kind and the scale over which they appear. I also discuss the importance of setting upper limits in SETI, and offer a heuristic for how to do so in a generic SETI search. I mention and attempt to dispel several misconceptions about the field. I conclude with some personal observations and recommendations for how to practice SETI, including how to choose good theory projects, how to work with experts and skeptics to improve one's search, and how to plan for success. -
Microwave Spectroscopy of Sulfur-Bearing Molecular Species Of
Microwave spectroscopy of sulfur-bearing molecular species of astrophysical interest by Wenhao Sun A thesis submitted to the Faculty of Graduate Studies of the University of Manitoba in partial fulfillment of the requirements of the degree of Doctor of Philosophy Department of Chemistry University of Manitoba Winnipeg, Canada Copyright © 2019 by Wenhao Sun Abstract Microwave spectroscopy, which measures rotational transitions in the centimeter-wave region, is a robust technique to study the fundamental chemical and physical properties of gaseous molecules, such as the geometry and the electronic structure. This thesis presents a selection of studies on several compounds of great astrophysical interest including phenyl isocyanate (PhNCO), phenyl isothiocyanate (PhNCS), ethynyl isothiocyanate (HCCNCS) and its longer chain form HCCCCNCS, cyanogen isothiocyanate (NCNCS) and its longer chain form NCCCNCS. The experiments were carried out with two Fourier transform microwave (FTMW) spectrometers: the broadband chirped pulse type, which has the capability of simultaneously probing many molecules together with a bandwidth up to 6 GHz; the narrowband cavity-based type, which focuses on a frequency window of 1 MHz each time with high resolution and sensitivity. Unlike PhNCO and PhNCS which are commercially available, the other four chemical species are not likely to be synthesized on a laboratory benchtop and were thus prepared by employing a dc electrical discharge. The transient products in the discharge source were probed by the spectrometers and were unambiguously identified by their rotational transitions out of a number of discharge dependent species including both closed-shell compounds and open-shell radicals. Furthermore, in order to better understand the chemical reactivities and kinetics in complex discharge plasmas, a thiazole discharge was investigated on the basis of the identified products in the rich spectrum.