Astronomy 1G Galactic and Cosmological Science

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1 Astronomy 1G Galactic and Cosmological Science Introductory Lecture Professor Andy Lawrence Today Introduction to Course Principles of Astronomical Science Whirlwind Tour of Universe 2 The team Prof Andy Lawrence al@roe.ac.uk Dr Catherine Heymans (Course Organiser) heymans@roe.ac.uk Dr Ken Rice wkmr@roe.ac.uk

2 Nature and Goals of Course Introductory astrophysics course Apply basic physics techniques to astrophysical situations Particular focus on understanding galaxies, black holes, and cosmology. Useful books : Introductory Astronomy and Astrophysics by M. Zeilik and S.A. Gregory. The Cosmic Perspective by Bennett, Donahue, Schneider and Voit. Components of Course 5 modules x 6 lectures 5 tutorials 1 piece of coursework 1 exam Mondays Lec(AT5) - Tut - Lec(AT5) Fridays Lec(DHT-A) - Tut 5 Course Modules The Science of Astronomy (Lawrence) The Milky Way and other Galaxies (Lawrence) Active Galactic Nuclei (Rice) Galaxies at Large (Lawrence) Cosmology (Heymans)

3 Course material and Registration Course booklet make sure you read it!! available at first lecture, online, and through P.T.O. Online material at My Ed portal / WebCT lecture notes, course booklet, self-tests notices, announcements, grades discussion board Registration form required so tutorial groups can be assigned please fill in today or v.soon 7 Tutorials Each student attends 5 tutorials one every two weeks Monday and Friday assigned during first week based on registration form Work in groups to answer exam-like Qs hand in solutions every two weeks best 4 out of 5 count towards final mark deadlines in course booklet deadlines are strict : no work accepted afterwards More detail in booklet 8 Assessed Coursework Assignments announced shortly deadlines in course booklet late hand in will lose 5% per day up to max of 5 days zero score thereafter need to complete an "Own Work Declaration" (available online) 9

4 Passing the course passmark based on : 2/3 exam 1/6 coursework assignment 1/6 assessed tutorial problems to pass, must score >40% overall to pass, must score >40% on exam 10 Crickets We will be using crickets (formally known as a Personal Response System) during lectures. If you don t already have a cricket, you will be able to collect one from the Darwin library (in the Kings Buildings) or during the next week from the Teaching Office on the 4 th floor of the James Clerk Maxwell Building (JCMB). The use of the crickets will be anonymous and they will be used primarily to promote interaction during the lectures. (They will not affect your exam marks.) Observing Free tickets for the Visitor Centre s public observing sessions on Friday nights will be able for first-year students interested in some stargazing and perhaps thinking about getting involved in outreach work. These tickets are limited and booking is essential. Contact the Visitor Centre ( , 2-4pm, vis@roe.ac.uk).

5 Module-1 : The Science of Astronomy Module-1 Lectures Introduction Scientific Method / Whirlwind Tour Gravity and Motion Radiation and Matter Astrophysical Spectra Distances and Magnitudes The Stars 14 Scientific Method What is science? science is the process by which we try to understand the world around us Science is quantitative definitive not vague criteria for testing Science is sceptical no appeal to authority relies on evidence and reasoning Theory is the endpoint of science provides an explanation it must be consist with existing observations and, be able to predict testable results Experimentation explore and discover test theories

6 Astrophysics Generally can t do experiments in the traditional sense Primarily relies on observations Still requires a measurement Probes to planets, moons and comets Direct measurements of interplanetary space Collect radiation from galactic and extra-galactic sources Experimentation, but not controlled. Requires an understanding of the underlying physics Mechanics Radiation and matter Atomic Physics Astrophysics is not a fundamental science Application of physics to understand objects in the Universe. What Science do we need to know? Gravitational dynamics Planetary orbits, Binary stars, Galaxy rotation Properties of Light Waves (interference, Doppler effect) Determine velocities and together with gravitational dynamics determines masses Expansion of the Universe Thermal Physics (thermal equilibrium, blackbody radiation) Temperatures of astronomical bodies Atomic Physics and Spectra Temperatures and composition Type of star/galaxy Can be used to determine distances Whirlwind Tour This course will concentrate on galaxies and the Universe at large But first lets get a broad picture of the contents of the Universe 18

7 Earth from Apollo 11 Earth and Moon from Voyager 1 Aurora and Meteor Jimmy Westlake Colorado Mountain College

8 John Young Apollo 16 : 1972 Mars Pathfinder Rover Sojourner Mars from Mars Global Surveyor Mercury from Messenger and Messenger Teams

9 Venus from Galileo flyby and Galileo Teams Jupiter from Buckinghamshire Damian Peach Volcano on Io : Voyager 2 : 1979

10 Saturn from Voyager 1 Uranus from Voyager 2 Neptune from Voyager 2 : 1989

11 Pluto All 88 solar system bodies larger than 200 miles Alan Taylor / kokogiak Dewey Vanderhoff Comet Halley from Michoacan, Mexico, UV light Sun TRACE satellite Visible light Sun amateur telescope

12 Starfield : NGC7039 and NGC J.Chumack Star properties : Hertzsprung-Russell diagram ESO Orion nebula, HST Constellation of Orion

13 Pleiades : UK Schmidt AAO/ROE M57 Ring Nebula in Lyra : HST Supernova 1987A : before and after AAO

14 Crab Nebula visible light W.Nowotny Nordic Optical Telescope M.Bietenholz Very Large Array, NRAO Crab Nebula radio Artist's impression : Low Mass X-ray Binary ESA Globular Cluster in Aquila UKIDSS/JAC

15 G.Garrad, Australia Fisheye camera view of Milky Way IRAS / Galactic Centre in far-infrared Constellation of Andromeda Jack Newton Bear Creek Observatory IRAS / M31 Andromeda Nebula NGC 2903 R.Croman Austin Texas NGC 891

16 Giant Elliptical NGC 1132 Hubble Space Telescope Dwarf Irregulars : Large and Small Magellanic Clouds Bill Keel / CTIO Jet in M87 Hubble Space Telescope

17 Coma Cluster, HST Abell 2029 Cluster : X-ray vs optical /Caltech Dark Matter made visible W.Couch /

18 Hubble Deep Field Expansion of Universe T.Harrison Spectrum of Cosmic Microwave Background COBE /

19 WMAP / Ripples in the Cosmic Microwave Background Some useful numbers Astronomical unit (pc) : 1.5 x m (Sun Earth distance) 1 parsec (pc) : 3 x m Speed of light (c) : 3 x 10 8 m 1 light year : distance light travels in a year (nearest star apart from Sun) 1 light second : distance to the moon 8 light minutes : distance to the Sun 1 light hour : distance across solar system 25 thousand light years : distance across the galaxy 150 thousand light years : distance to the Magellanic galaxies 1 million light years : distance to M31 (nearest big galaxy) 1000 million light years : size of universe