Astronomy 1G Galactic and Cosmological Science
Introductory Lecture Professor Andy Lawrence
Astronomy 1G 2011-12
Today
• Introduction to Course • Principles of Astronomical Science • Whirlwind Tour of Universe
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The team
Dr Catherine Heymans Prof Andy Lawrence Dr Ken Rice (Course Organiser) [email protected] [email protected] [email protected]
Astronomy 1G 2011-12 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.
Astronomy 1G 2011-12
Components of Course
• 5 modules x 6 lectures • 5 tutorials • 1 piece of coursework • 1 exam
Mondays 1400-1700 Lec(AT5) - Tut - Lec(AT5) Fridays 1400 - 1550 Lec(DHT-A) - Tut
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Course Modules
• The Science of Astronomy (Lawrence)
• The Milky Way and other Galaxies (Lawrence)
• Active Galactic Nuclei (Rice)
• Galaxies at Large (Lawrence)
• Cosmology (Heymans)
Astronomy 1G 2011-12 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
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Tutorials
• Each student attends 5 tutorials – one every two weeks – Monday and Friday 1500-1550 – 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
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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)
Astronomy 1G 2011-12 9 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
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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 4th 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.)
Astronomy 1G 2011-12
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 (0131-6688404, 2-4pm, [email protected]).
Astronomy 1G 2011-12 Module-1 : The Science of Astronomy
Astronomy 1G 2011-12
Module-1 Lectures
• Introduction • Scientific Method / Whirlwind Tour • Gravity and Motion • Radiation and Matter • Astrophysical Spectra • Distances and Magnitudes • The Stars
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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
Astronomy 1G 2011-12 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.
Astronomy 1G 2011-12
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
Astronomy 1G 2011-12
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
Astronomy 1G 2011-12 18 Earth from Apollo 11 NASA
Earth and Moon from Voyager 1 NASA
Jimmy Westlake Aurora and Meteor Colorado Mountain College John Young Apollo 16 : 1972 NASA
Mars Pathfinder Rover Sojourner
Mars from Mars Global Surveyor NASA
NASA and Mercury from Messenger Messenger Teams NASA and Venus from Galileo flyby Galileo Teams
Damian Peach Jupiter from Buckinghamshire http://www.damianpeach.com/
Volcano on Io : Voyager 2 : 1979 NASA Saturn from Voyager 1 NASA
Uranus from Voyager 2 NASA
Neptune from Voyager 2 : 1989 NASA Pluto
All 88 solar system bodies larger than 200 miles Alan Taylor / kokogiak http://kokogiak.com/solarsystembodieslargerthan200miles.html
Dewey Vanderhoff http://reddit.wired.com/submissions_night_photo/
Comet Halley from Michoacan, Mexico, 1987
UV light Sun TRACE satellite
http://www.astropix.com
Visible light Sun amateur telescope http://www.astropix.com
NASA ©.2009 J.Chumack Starfield : NGC7039 and NGC7048 http://www.galacticimages.com/
ESO Star properties : Hertzsprung-Russell diagram
http://www.davidmalin.com/fujii/fujii_index.html
Orion nebula, HST
Constellation of Orion NASA Pleiades : UK Schmidt AAO/ROE
M57 Ring Nebula in Lyra : HST NASA
Supernova 1987A : before and after AAO W.Nowotny Crab Nebula visible light Nordic Optical Telescope
M.Bietenholz Very Large Array, NRAO Crab Nebula radio
ESA Artist's impression : Low Mass X-ray Binary
UKIDSS/JAC Globular Cluster in Aquila http://surveys.roe.ac.uk/wsa/gallery/wsa_gps/ G.Garrad, Australia Fisheye camera view of Milky Way
http://www.public.asu.edu/~rjansen/localgroup/localgroup.html
IRAS / NASA
Galactic Centre in far-infrared
http://www.davidmalin.com/fujii/fujii_index.html Constellation of Andromeda
Jack Newton Bear Creek Observatory
IRAS / NASA
M31 Andromeda Nebula http://www.bearcreekobservatory.com/
NGC 2903
©R.Croman http://www.rc-astro.com/ Austin Texas
NGC 891 Giant Elliptical NGC 1132 Hubble Space Telescope
NASA
Dwarf Irregulars : Bill Keel / CTIO Large and Small Magellanic Clouds
Jet in M87 Hubble Space Telescope
NASA NASA Coma Cluster, HST
Abell 2029 Cluster : X-ray vs optical
NASA/Caltech
Dark Matter made visible W.Couch / NASA Hubble Deep Field NASA
Expansion of Universe
T.Harrison
Spectrum of Cosmic Microwave Background COBE / NASA WMAP / NASA
Ripples in the Cosmic Microwave Background
Some useful numbers
Astronomical unit (pc) : 1.5 x 1011 m (Sun Earth distance) 1 parsec (pc) : 3 x 1016 m Speed of light (c) : 3 x 108 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
Astronomy 1G 2011-12